2003 Prius Stuck between 2 coconut trees for 3 months now, Need some help!!

jdenenberg · Apr 5, 2013

Bob,

A reasonable approach. The zeners do have a a voltage tolerance specification (usually 5%, sometimes 10%, but 1% is available at a price which would get the modules within 0.1v or so see:Vishay - Diodes - Zener diodes - Tolerance 1%), so there will be a variation from module to module when the battery stabilizes.

You could also just go with a BMS made for EVs.

JeffD

jonathan T · Apr 5, 2013

Guys i am bummed
I think i trashed my batts more by load testing them.
I just drove(if you can call it that!) 20 miles,
The car acted so weird.
It didnt have accelerator power at times, it was jerky at times, ran fine around 60% of the time.
I once tried to reverse and there was no power, till i shut it off and on again.
I must of erased 10 different code times during the trip.
It would start to make a strange sound and throw the P3006 and P3006p code.
Still dont know what the difference between those codes are?
Threw a P3019 code figuring thats block #9
I am not clear what my next move is?
Do i go into the hv batt and take readings on each individual cell, and see if there is big variance between them?
Do i need to get that DC6 charger and start to do that to each battery?
I have a one shot deal to get batts and equipment here via American Samoa but those parts wont come here till mid May.
Ok so is my next step to try and charge/ balance my batts ?
Did the load tester put to much of a stress on the batts and they now are failing?
OK all ears again

jdenenberg · Apr 5, 2013

How much current did the load tester pull for how long?

JeffD

jonathan T · Apr 5, 2013

jdenenberg said: ↑

How much current did the load tester pull for how long?

JeffD
Click to expand...

Its a regular load tester that mechanics have to test regular 12 volt battery, but also 6 volt batteries.
I held the switch on each battery for 5 seconds.
So what is my best next step??
do the charger thing you spoke of earlier?

ahmeow · Apr 5, 2013

Wow what a great advanture. Glad the OP's Gen 1 back to working codition and happy.
We also learn a lot.

bwilson4web · Apr 6, 2013

jonathan T said: ↑

. . .
Ok so is my next step to try and charge/ balance my batts ?
. . .
Click to expand...

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. ) When the plastic fiber separator gets too hot, it melts at a spot and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and the rapid temperature rise and expanding case are only briefly, a minute or so, detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that at near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson

jdenenberg · Apr 6, 2013

Listen to Bob. I bought a ReInVolt for my 2004 Prius and then re-balanced the 27 good modules (of 28) and sold them to others for fixing their HV batteries. Net cost ~$1200.

JeffD

jonathan T · Apr 8, 2013

jdenenberg said: ↑

Listen to Bob. I bought a ReInVolt for my 2004 Prius and then re-balanced the 27 good modules (of 28) and sold them to others for fixing their HV batteries. Net cost ~$1200.

JeffD
Click to expand...

Hi Guys

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

Hi Guys
OK Its 1 am and i am awake researching like a mad man.
I just reread your post Bob, thank you very much for the good info and pictures!
Thanks for the advice Jeff
Ok i need to find out for sure if the batteries are failing before dumping another 2k+ into the car.
It makes it all trickier being on a remote island, where shipping costs and lag time is a killer.
The reason why i keep scratching my head on the batts is because:
1: When i load tested (i now know hard on the batts) i put the load on each individual cell for 5 to 8 seconds, they all were resting between 7.63 & 7.69 most @ 7.66 and all of them held at 6 volts no lower during the load.
2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.
3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.
Bob i really see i am at a disadvantage by not having a prius aware scanner here, as running back and forth with the voltage meter between tests is not as accurate as i like it and a pain!!
4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.
First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437p came up again which i have yet to address.
Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96
Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor. I re cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.
After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70
Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.
Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?
I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.
Ok all ears again.
Thanks all for the great forum!!
Jonathan

bwilson4web · Apr 8, 2013

* * * Comments inserted * * *

2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.

Other codes?

3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.

16.52 - 16.25V = 0.27V :: very close to the 0.3 V that triggers a P3006.

Sounds like the charge is not equalized BUT if the replacement modules have more Ahr capacity, this too would explain why they show up with a lower voltage after a forced charge. Do they have a higher voltage during the forced discharge?

In theory, you might be able to re-order the pack putting a 'new module' with a 'weak module' in a pair. The wider voltage swing of a weak module would be matched to the smaller voltage swing of a stronger module. . . . in theory.

4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.

Are these P3006 codes coming up during drives versus the forced charge and discharge? If so, it would suggest something is still loose. Are the module footer screws/bolts in? The compression rods tight? Any flex would lead to arcs when driving or under vibration. If you have a rubber mallet, hitting around the traction battery case, possibly just rocking the car, might 'initiate' the arcs.

First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437 came up again which i have yet to address.

Can you take photos of the arcs? Use the video record option of a digital camera and have someone else start the car and/or have the camera on a tripod and running while you start the car? Later, pull the specific 'arc' frames from the digital video file?

You had mentioned the control electronics 'were burnt up' and had to be replaced. Now I'm wondering if there may be broken or weak pins in that area. There was a Japanese lady who had a broken pin in a connector and that turned out to be very difficult to diagnose and repair.

Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96

Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor.

I re-cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.

Sparks are bad! It suggests there are leaks to the case. Alternatively, the pack is not mechanically rigid. The KOH and related salts are hydroscopic and the 'arcs' are likely the charge leaking through the conductive path. But any relative motion between modules and the buss bars are going to arc.

After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70

15.93 - 15.70 = 0.23V :: within the 0.30V limit

Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.

Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?

This reads as if there are either loose or still corroded buss bars and/or possibly leaks to the case. Worse, the pack has to be mechanically rigid. Any vibration because the compression rods are loose and footer bolt/screws missing would be bad.

I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.

You know more about your situation, time and resources than any of us. We can advise but not decide.

Bob Wilson

ChapmanF · Apr 8, 2013

Hmmmm.

The bus segments are mounted in plastic, and then plastic covers go over them, right? I assume you only left those outer bus covers off.

The difference between two adjacent bus segments shouldn't be much over 16 V normally, which I wouldn't think enough to start an arc across the gap between them.

I think the typical internal resistance of a module pair is around 22 milliohms, which shouldn't add more than about two volts between segments at a 100 A charge or discharge. Again, the segments aren't close enough for 18 V to jump the gap, are they?

A larger voltage difference could develop across a module pair with an especially high internal resistance ... or across a high-resistance terminal connection.

A ground fault between any module and the case could make large voltages appear between the case and other modules further away.

I would certainly recheck the work again ... we know arcing is not the normal intended behavior, so a recheck "which showed correct" might have been a recheck that just wasn't thorough enough to find the trouble.

Please work safely.

-Chap

jonathan T · Apr 9, 2013

jdenenberg said: ↑

Listen to Bob. I bought a ReInVolt for my 2004 Prius and then re-balanced the 27 good modules (of 28) and sold them to others for fixing their HV batteries. Net cost ~$1200.

JeffD
Click to expand...

Hi Guys

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

Hi Guys
OK Its 1 am and i am awake researching like a mad man.
I just reread your post Bob, thank you very much for the good info and pictures!
Thanks for the advice Jeff
Ok i need to find out for sure if the batteries are failing before dumping another 2k+ into the car.
It makes it all trickier being on a remote island, where shipping costs and lag time is a killer.
The reason why i keep scratching my head on the batts is because:
1: When i load tested (i now know hard on the batts) i put the load on each individual cell for 5 to 8 seconds, they all were resting between 7.63 & 7.69 most @ 7.66 and all of them held at 6 volts no lower during the load.
2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.
3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.
Bob i really see i am at a disadvantage by not having a prius aware scanner here, as running back and forth with the voltage meter between tests is not as accurate as i like it and a pain!!
4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.
First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437p came up again which i have yet to address.
Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96
Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor. I re cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.
After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70
Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.
Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?
I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.
Ok all ears again.
Thanks all for the great forum!!
Jonathan

bwilson4web said: ↑

* * * Comments inserted * * *

2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.

Other codes?

3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.

16.52 - 16.25V = 0.27V :: very close to the 0.3 V that triggers a P3006.

Sounds like the charge is not equalized BUT if the replacement modules have more Ahr capacity, this too would explain why they show up with a lower voltage after a forced charge. Do they have a higher voltage during the forced discharge?

In theory, you might be able to re-order the pack putting a 'new module' with a 'weak module' in a pair. The wider voltage swing of a weak module would be matched to the smaller voltage swing of a stronger module. . . . in theory.

4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.

Are these P3006 codes coming up during drives versus the forced charge and discharge? If so, it would suggest something is still loose. Are the module footer screws/bolts in? The compression rods tight? Any flex would lead to arcs when driving or under vibration. If you have a rubber mallet, hitting around the traction battery case, possibly just rocking the car, might 'initiate' the arcs.

First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437 came up again which i have yet to address.

Can you take photos of the arcs? Use the video record option of a digital camera and have someone else start the car and/or have the camera on a tripod and running while you start the car? Later, pull the specific 'arc' frames from the digital video file?

You had mentioned the control electronics 'were burnt up' and had to be replaced. Now I'm wondering if there may be broken or weak pins in that area. There was a Japanese lady who had a broken pin in a connector and that turned out to be very difficult to diagnose and repair.

Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96

Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor.

I re-cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.

Sparks are bad! It suggests there are leaks to the case. Alternatively, the pack is not mechanically rigid. The KOH and related salts are hydroscopic and the 'arcs' are likely the charge leaking through the conductive path. But any relative motion between modules and the buss bars are going to arc.

After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70

15.93 - 15.70 = 0.23V :: within the 0.30V limit

Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.

Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?

This reads as if there are either loose or still corroded buss bars and/or possibly leaks to the case. Worse, the pack has to be mechanically rigid. Any vibration because the compression rods are loose and footer bolt/screws missing would be bad.

I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.

You know more about your situation, time and resources than any of us. We can advise but not decide.

Bob Wilson
Click to expand...

7 CODES DOWN TO 1! I HAVE WONDERFUL NEWS TO SHARE AND A CONCLUSION TO THE P3006 AND VARIOUS OTHER WEAK BLOCK CODES!!!

OK First, a big thank you to Bob, Jeff and all others who have posted, i feel like a young jetti coming up the ranks with very good teachers.

CORROSION CORROSION CORROSION, as well as not properly tighten down nut to battery posts.
I thought i had cleaned the wiring harness well enough but i was dead wrong. My first 3 cleanings were only superficial at best. I had initially scrubbed with a tooth brush and baking soda, then followed by a scrub with alcohol with a soft small wire brush. This took some off, but not nearly enough, to have proper connections. That coupled with various semi loose nuts on the post of the batts had caused all the P3006 codes, all the various P3011-thru P3029 codes, all the sparking and arcs, all the sleepless nights and me scratching my head as each battery tested good from my first load testing(which i know was heavy on them, but praise God, did not damage them) to the 2nd load testing (which was done by taking out both my headlights, wiring them in paralel and putting them and a volt meter on each cell for 8 seconds measuring: resting voltage to start of load voltage to end of load voltage, whew a prius aware scanner would be way easier!!)
Now the real cleaning came when i took each copper bus bar out of the plastic housing (easy to do with a thin flat head, and for the sensor tabs just being careful when removing those( theirs a small tab on top of each sensor that can be pried out off the plastic housing carefully) And sanding down each coper bus bar till i saw copper!.
I posted pics so one can see the difference in the wiring harness cleanings.
So with all those nasty codes out of the way i am left with 2 things to tackle and some questions:
1: Anyone got a fix for P1437 ( in the forum i saw it was some type of vacum code?)

2: How do i improve my MPG, its down to 36 and i know it could be better. Maybe just things to do, check, etc... that would get that higher.

3: Bob, Jeff, anyone else can you weigh in on this for me: So with the load test figures i already posted and the 2nd load test figures of resting voltage anywhere between 7.88 to 7.74 then to most module beginning load testing voltages of 7.70 down to 7.60, with a few modules beginning load testing from 7.62 down to 7.50v. Is there a way from such figures, plus the mileage (122k) plus the years of batts (10 years) that i can understand how much life expectancy is left in the modules?
Would MPG have any play in the posted figures above (like if they would new batts would the resting voltages etc... be higher and the load voltages would not go down as much?)

4: Would it be worth investing in that DC6 charger and charge/discharge / charge to extend battery life expectancy?

Ok Thank you all especially Bob for all the helpful posts!!!
Look forward to hearing from you &
YES ANOTHER PRIUS CHAT SUCCESS!!!

bwilson4web · Apr 9, 2013

As long as the greatest dV between the lowest and highest is less than 0.3V, you are 'OK' for now.

Long term:

corrosion source - is probably leaked KOH. I'm sorry I didn't mention this but IF you have to go back and clean the buss bars again, be sure and wipe/neutralize any residual electrolyte on the modules. One of the things ReInVolt does is nickel plate their buss bars since nickel is relatively immune from KOH. Gold plating is another, more expensive option but only if you need to fund retirement later. <GRINS>

Prius-aware scanner - there are things other than batteries that can go 'boink' but it really would have made your battery exercise . . . a little more insightfull

do not be surprised if another battery problem shows up in 3-6 months - if you get past this infantile failure point, you probably have years of service in the future. Most of the single-module replacement failures were reported with 6 weeks to 3 months. If you make it past this time, rest easy.

GOOD LUCK!
Bob Wilson

jonathan T · Apr 9, 2013

jdenenberg said: ↑

Listen to Bob. I bought a ReInVolt for my 2004 Prius and then re-balanced the 27 good modules (of 28) and sold them to others for fixing their HV batteries. Net cost ~$1200.

JeffD
Click to expand...

Hi Guys

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

bwilson4web said: ↑

An NiMH battery consists of a nickel electrode, a plastic fiber separator, a metal hydride matrix, and very concentrated potassium hydroxide and water electrolyte (see pri_batt_280.jpg. View attachment 49227 ) When the plastic fiber separator gets too hot, it melts and that makes a permanent short inside that cell battery.

In normal operation, each cell goes through charge and discharge cycles (see pri_batt_530.jpg. View attachment 49228 ) During the charge cycles, they get warmer but during the discharge, they hold the heat. Also, a small amount of gas is generated and as the cells get warmer, the internal pressure increases.

At higher temperatures, the heat and pressure causes some of the gas and a small amount of electrolyte to leak out a terminal (see pri_batt_900.jpg. View attachment 49229 ) To minimize the problem of terminal leaks, Toyota developed a technique using 'glue' and an absorbing pad to prevent a short to ground. But the "O" rings suffer and melt leading to a black, rubbery stain around where the terminal comes out of the plastic case. The little bit of KOH electrolyte 'eats' copper.

If unchecked, over charging expands the battery case and can destroy the battery (see pri_batt_400.jpg View attachment 49230 ). This is why ordinary 6V and 12V battery chargers and testers are a poor idea. They do not have a sensitive temperature probe or accurate voltage monitor to prevent damaging the modules. The window for failure is very small and there the rapid temperature rise and expanding case is only briefly detectable before permanent damage is done.

The Radio Control community has been dealing with NiMH batteries for years and developed much improved chargers (see pri_batt_060.jpg. View attachment 49231 ) Prices and capabilities vary but key features are a temperature probe, logic to detect the dV change at peak charge, and a memory to record how much charge was put in and during a subsequent discharge, taken out. This is how I measure the Ahr capacity of modules.

Now others have also tried to replace failed modules in the traction battery but it has a success rate of 25-33% (see pri_batt_440.jpg. View attachment 49232 ) In this case, two failed modules were replaced but other weaker modules failed soon. It is the battery equivalent of putting new wine in old wine skins. The replacement modules can lead to early failure of other modules, it soon becomes an unwelcome time and money pit. It is equivalent to bailing a boat without fixing the leak.

In 2004, Toyota came out with an improved module design (see pri_batt_960.jpg View attachment 49235 ) that reduces the concentration of heat at the terminals. With about 700,000 NHW20 cars, 2004-09 on the road, accidents take them out fast enough to provide these improved modules for rebuilding the failing NHW11 traction batteries. But these modules come in all 'states' of wear.

There are a few shops that actually 'survey' these salvaged modules so only the good and matched ones are equally charged and assembled into good, replacements (see pri_batt_730.jpg. View attachment 49236 ) ReInVolt of Summit North Carolina does this for ~$1,800, not counting shipping. They require the old battery electronics and case, not the modules, to be returned for a core charge, ~$500 (?). But ReInVolt is not the only quality rebuilder but I know they do a good job and stand by their work.

To rebuild a traction battery:

smart RC battery charger that has temperature and dV logic for NiMH batteries with a data recording capability.

inventory of modules - to wind up with 38 modules knowing most are already bad, about 19 extra are needed.

survey of all modules, find the 38 that near equal Ahr capacity which takes about 12-18 hours per module.

if there is more than a 10% difference between the low and high modules of the closest 38, buy more and keep testing until you have a good set.

balance charge all 38 modules using the parallel wire trick or a final charge to the same cutoff voltage.

reassemble the battery.

enjoy years of Prius service remembering to keep the traction battery away from heat.

A quality, battery rebuilder does this already using the newer, NHW20 modules. They have inventory, the technology, and the skill to do the job right.

Another alternative is Toyota will sell a replacement set of NHW11 modules for about $2,200-2,400. It is a simple process to do a one-time replacement of all modules. However, these new modules still use the same design weakness as before. In contrast, the used NHW20 modules have some 'age' but a superior design.

So you have choices, pick two from Good, Fast, and Cheap:

Good and Fast - Toyota replacement, battery pack

Good and Fast - rebuilt pack from rebuilder

Cheap - do it yourself and resell left-overs

GOOD LUCK!
Bob Wilson
Click to expand...

Hi Guys
OK Its 1 am and i am awake researching like a mad man.
I just reread your post Bob, thank you very much for the good info and pictures!
Thanks for the advice Jeff
Ok i need to find out for sure if the batteries are failing before dumping another 2k+ into the car.
It makes it all trickier being on a remote island, where shipping costs and lag time is a killer.
The reason why i keep scratching my head on the batts is because:
1: When i load tested (i now know hard on the batts) i put the load on each individual cell for 5 to 8 seconds, they all were resting between 7.63 & 7.69 most @ 7.66 and all of them held at 6 volts no lower during the load.
2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.
3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.
Bob i really see i am at a disadvantage by not having a prius aware scanner here, as running back and forth with the voltage meter between tests is not as accurate as i like it and a pain!!
4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.
First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437p came up again which i have yet to address.
Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96
Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor. I re cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.
After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70
Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.
Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?
I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.
Ok all ears again.
Thanks all for the great forum!!
Jonathan

bwilson4web said: ↑

* * * Comments inserted * * *

2: I am not seeing any batts that are more then a .2volt difference although i keep getting a repeat code of P3006, and various other codes of weak battery blocks.

Other codes?

3: I did the forced charge and forced drain & then charge like you said Bob, and 17 module pairs went back between 16.52 & 16.5, except the 4 replaced modules which were at 16.25& 16.26v. The total battery pack was operating between 295v and 303 volts at rest and is holding at 301v.

16.52 - 16.25V = 0.27V :: very close to the 0.3 V that triggers a P3006.

Sounds like the charge is not equalized BUT if the replacement modules have more Ahr capacity, this too would explain why they show up with a lower voltage after a forced charge. Do they have a higher voltage during the forced discharge?

In theory, you might be able to re-order the pack putting a 'new module' with a 'weak module' in a pair. The wider voltage swing of a weak module would be matched to the smaller voltage swing of a stronger module. . . . in theory.

4: Now some things i have to mention
When i took the car on another test run after i had again thoroughly cleaned all the bus bars and tired to take most the corrosion off, and reassembled and tightened down , i had the pack exposed with no metal cover nor plastic cover & a few bolts so i can get easy access to it.

Are these P3006 codes coming up during drives versus the forced charge and discharge? If so, it would suggest something is still loose. Are the module footer screws/bolts in? The compression rods tight? Any flex would lead to arcs when driving or under vibration. If you have a rubber mallet, hitting around the traction battery case, possibly just rocking the car, might 'initiate' the arcs.

First when i started the car a large spark came from the middle of module pairs emanating out of the trunk side connections. I immediately shut it off and rechecked my work which showed correct, so i started again and no sparks, BUT when i went down the road when the car was switching between ev mode and gas, sparks came again, but this time not as big, but still noticeable, not just from the same middle area but from left side and right side mostly trunk side connections, some in the front but smaller. I got the P3006 code multiple times and various weak block codes, and code P1437 came up again which i have yet to address.

Can you take photos of the arcs? Use the video record option of a digital camera and have someone else start the car and/or have the camera on a tripod and running while you start the car? Later, pull the specific 'arc' frames from the digital video file?

You had mentioned the control electronics 'were burnt up' and had to be replaced. Now I'm wondering if there may be broken or weak pins in that area. There was a Japanese lady who had a broken pin in a connector and that turned out to be very difficult to diagnose and repair.

Now when i forced loaded the batts by having in neutral & all electrical loads on, i read voltage readings of the 19 modules as the following:
All 16 paired mods were between 14.98 & 15.11
17= 15.13
18= 14.92
19= 14.96

Now during that load test in neutral the car shut down and the main battery light lit up small in the upper right hand corner of the systems monitor.

I re-cleared the codes, started the car up and put into park and the gas engine came on and off every 20 to 30 secs or so multiple times, this is when small sparks would fly from the rear connections of the battery modules.

Sparks are bad! It suggests there are leaks to the case. Alternatively, the pack is not mechanically rigid. The KOH and related salts are hydroscopic and the 'arcs' are likely the charge leaking through the conductive path. But any relative motion between modules and the buss bars are going to arc.

After test driving module pairs 1 thru 17 read between 16.75 & 16.79
Modules 18= 16.58
Modules 19= 16.59
@ rest after the test drive total pack measured 303v
12 hours later i took a voltage reading of the modules:
1= 15.93v
2:15.87
3= 15.85
4: 15.83
5 thru 9= 15.82
10 thru 15 =15.84
16= 15.86
17= 15.88
18= 15.65
19= 15.70

15.93 - 15.70 = 0.23V :: within the 0.30V limit

Maybe the batts are not good and i just dont know how to read it correctly
It was so easy for me to see the 4 bad modules as they read under 2 volts, and 1 of them was negative.

Ok so are the sparks a sign of leaking modules or something to ground, or because i didnt have the plastic covers on them and i was heavily charging and discharging?

This reads as if there are either loose or still corroded buss bars and/or possibly leaks to the case. Worse, the pack has to be mechanically rigid. Any vibration because the compression rods are loose and footer bolt/screws missing would be bad.

I know the car toward the end of my 3 mile test drive went into limp mode and jerked around a bit.
I was thinking if it is definitely the batts and at 10 years old and 122k on them is most likely i would look to get gen 3 batts so i am more sure they would be good ones and not older gen 2 batts.

You know more about your situation, time and resources than any of us. We can advise but not decide.

Bob Wilson
Click to expand...

7 CODES DOWN TO 1!I HAVE WONDERFUL NEWS TO SHARE AND A CONCLUSION TO THE P3006 CODE!!!

bwilson4web said: ↑

As long as the greatest dV between the lowest and highest is less than 0.3V, you are 'OK' for now.

Long term:

corrosion source - is probably leaked KOH. I'm sorry I didn't mention this but IF you have to go back and clean the buss bars again, be sure and wipe/neutralize any residual electrolyte on the modules. One of the things ReInVolt does is nickel plate their buss bars since nickel is relatively immune from KOH. Gold plating is another, more expensive option but only if you need to fund retirement later. <GRINS>

Prius-aware scanner - there are things other than batteries that can go 'boink' but it really would have made your battery exercise . . . a little more insightfull

do not be surprised if another battery problem shows up in 3-6 months - if you get past this infantile failure point, you probably have years of service in the future. Most of the single-module replacement failures were reported with 6 weeks to 3 months. If you make it past this time, rest easy.

GOOD LUCK!

Bob Wilson
Click to expand...

Ok Bob Gotcha on that, i dont have access to nickel coating, what about a thin layer of vaseline on all connections?
Now onto:
1: Someone told me a prius aware scanner for like $35 on ebay, he called it TIS, do you know of this?
2: Any insights on P1437, or should i just scour the chat forum?
3: Would a DC6 charger and cycling the batts extend the life of them?
Thanks Bob!
J

fred stein · Apr 11, 2013

3prongpaul said: ↑

When you tried starting did the READY indicator light?

If not, try this;

To mate the HV ECU to the immobilizer you need to:

-ensure the 12V battery is fully charged , perhaps even "jump" another battery to the existing one.
-Turn key to ON position (not start)
-Wait at least 30 minutes (this is why you need a healthy battery)
-Turn key off.
-Turn key on. Car should READY up.

No need to jump any pins with paperclips etc.
Click to expand...

thanks, i will try this on my 01. i have triangle and main battery on computer screen. i also cannot get key out unless i disconnect the neg terminal. so maybe this will resolve my cars issue to ready. previous owner installed a reman hv battery and a new 12v toy battery. the car ran for 15 minutes and quit. i want to know what the configuration is for on the positive post cable on the 12 volt. there appears to be a small knive fuse, a clear lense and a black wire that seems a little loose. i dont know how to describe it. its connected but not tight on a push in clip. i bought vol 2 service from a prius owner, and ordered vol 1 off of amazon. i wont disconnect anything other than the 12 v until i have a better grasp of what im into. i will try to jump another battery on for a half an hour. once the electonic bugs are done, the old girl could have a fuel delivery problem. it sat for 3 years.

ChapmanF · Apr 12, 2013

bwilson4web said: ↑

corrosion source - is probably leaked KOH. I'm sorry I didn't mention this but IF you have to go back and clean the buss bars again, be sure and wipe/neutralize any residual electrolyte on the modules.
Click to expand...

Also, in case it hasn't been mentioned before, the KOH electrolyte is strongly alkaline already, so baking soda is not the first choice for cleaning up and neutralizing it. (People do use baking soda for cleaning up lead-acid batteries, since their electrolyte is, well, acidic.) For around the traction battery, Toyota literature specifies boric acid, and I've heard of people using vinegar if they have that handy and not the boric acid.

By this point, your corroded-then-burned-then-baking-sodaed-then-alcoholed-then-sanded bus segments will probably hold for a while. and you might be able to think about just ordering replacement bus bar assemblies. Even if it's a pain to get them delivered to where you are, maybe you could have them on hand by the next time you have a reason to go into the battery. If you look around this forum for the old TSB on battery terminal resealing, it gives the order number for a parts kit for that job, which includes all new busbar assemblies and a few other goodies like resin endplates that weren't in the original design. (In other words, their TSB instructions were always to unconditionally replace the busbars, even though the batteries were only a few years old when the TSB came out.)

I don't know whether ReInVolt would sell you their nickel-plated busbars a la carte, but it might be worth contacting them to find out.

-Chap

ericbecky · May 9, 2013

You can get a set of bus bars from online parts houses or dealers. Often a better option than dealing with used ones.

Also, I have customers that use and aftermarket full-pack charger that costs ~$1,000. It can help keep older packs alive.
But ultimately, at some point a different pack (rebuilt) may be necessary.
There are other companies out there that we use (Like Adopt a Part) that also have rebuilt packs that are tested and warrantied.

Andyprius1 · Feb 7, 2017

jonathan T said: ↑

HI All you Prius Enthusiasts!!!

I am very grateful to have found this forum as i am the only Prius owner on this island!!
Ok i am in a real pickle, My Prius has been stuck for over 3 months now in between 2 coconut trees (i am not even joking!!) and am scratching my head as what to do next.
I am posting here but think i will also copy and post as new question.
Let me try to be brief(its going to be hard!lol)
I am an American on a tiny island in the south Pacific in a country called the Kingdom of Tonga doing long term missionary work.
Gas here is $8.50 a gallon, so i thought i was slick to ship my 2003 prius over.
OK 3 months ago, i by accident burnt my only master key in a brush fire, i know like DUH!
There is no mechanics, nor equipment on the island that can even come close to understanding what to do or what a Prius even is(but boy can they crack open coconuts good!!).
So after much research i purchased a new ECU Immobilizer and Ignition kit and had it hand delivered over by a incoming friend . (You guys are so flippin blessed with fed x, ups, etc.... as shipping from anywhere takes 5 to 8 to NEVER, in getting here!!)
Ok installed the new Kit and put the key in and the immobilizer light turned off when i inserted the key, and turned back to blinking when i took it out, but did not start and the Triangle of death indicator light came on, along with P.S (as i recall?) and Main Battery light.
So after much research and seeing a utube video of Prius King revamping a Hybrid battery (thank you Prius King for the confidence and videos!!) I purchased 4 used battery modules and a used ECU Battery assy computer along with a new orange wiring harness, because when i checked my Hybrid battery 4 modules were reading Negative readings! (The other 34 batts were reading 7.6 volts, the 4 replacement mods are reading 7.3v, and 7.4 volts). The Ecu Computer had a electrical fire in it and the wiring harness coming out of the ECU Batt assy computer melted and wires fried etc..... ( i have a theory as what possibly happened here but not sure, The day i burnt the key in the brush fire the Prius was 15 feet or so from the fire. What i am thinking is: could battery numbers 34-38 being closet to the passenger side and the fire get heated up and short from the heat and fry the batt assy and wiring harness??)
Anyway after another 4 weeks i just got my 4 used mods, and other ECU batt assy computer and wiring harness, and installed it in the prius and this is what happened:
~I put the key in and the Immobilizer light turned off.
~ I turned to start the car
~ i heard what i think is a normal click sound from the hybrid battery
~ But car does not start???
~ No Triangle of Death Indicator light is on
~ No Main Battery light is on
~ NO P.S. Light on
~ There is a check engine light on, But thats been on for ages i think its because the A/C is gone, but that could be wrong, but i dont think it is due to no start issue
~ There is a low collant light on
~ The fuel light is blinking on the last bar, but i know this is not correct as the gas tank is full???
~ I believe the ready light turns on but i have to double check that
~ The battery level on the Energy monitor screen shows low but not empty
~I moved the shifter thru some gears to see if it would roll, Nope
~Tried restarting, NOPE
~ I then turned off and pulled the main disconnect on the Hybrid battery and tried to start car to see what it would do, Triangle of Death came on.
~ Then turned key off and put hybrid disconnect back in and Turned Key on and Triangle of Death was still on.
~Then unplugged 12volt battery and plugged back in and tried to start car again, did not start but the triangle of Death indicator was off.
With my incoming parts from the usa I purchased a cheap scanner U480
~plugged that in and scanned and got no codes at all
~ But then when looking at I/M readiness status (which i dont really understand) i got:
MIL off
and then i scroll around and it says:
HO2s Not ready, O2S Not ready, evap not ready/ Cat not ready
Hdm N/a, 2air n/a, a/c N/a, Egr n/a
Under Ready it states Misfire, fuel and CCM
~ Then i went to the fuse box to see if i could see anything there.
Moved around some relays, (i knew the horn relay was working so moved that around to all other spots) Nada
OK So i am scratching my head at what to do Next???
There are no parts on this island so anything i need to get needs to be shipped in , so i am praying i dont need parts!!
My wife has been a real sport with all this as are transport has been my scooter. I should send a photo of Her, our new baby (9 months old) bundled and strapped to my wife and myself cruising down the road trying to avoid the massive pot holes, 22,000 pigs and carrying our papaya baskets and coconuts back home!!
Ok i look forward to the informative replies and want to thank you all in advance .

Sincerely

Jonathan T
Click to expand...

This is the most incredible and funniest post I have ever read.

gittarpikk · Jul 4, 2017

Maybe should have titled this Gen 1 Module tolerance...

Ok... seems to be most relevant thread so here goes..
Gen 1 ...rebuilt pack about a year and a half ago finding only 7 modules needed replacing....but was getting red triangle , engine light etc.

Rebuild great success...but couple months after rebuild, WalMarts crappy oil team overfilled oil and I had to pull back into bay as engine was dying. They attempted probably 20-25 restarts killing the main as well as the aux battery ( I should have suited them).. I towed the car to the house rather than the toyota dealer...tore it apart again and individually recharged each module as I have a dual 200 watt pro RC charger. ...then found the aux battery at 10 volts ...so did a tractor battery trick someone suggested (which works perfect ...has only needed 2 in a year and a half ...and at $30 each is a steal)...
got it running and ran perfect for well over a year. Then I started having abs problems (yet another issue) but of late, (in addition to the abs issue) I began getting P3024 block weak errors...and once a P3023 weak block as well....also get P3000 battery control system error.
I could reset them and get by maybe a half day on my route (120 miles full route) before it would set another code.
But it began to get worse...and shut me down on side of highway (that had the second block weak error and p3000) once so figured its time to tear it down again..
This time though, no red triangle./engine light)

Now its apart on bench...

2 days since came off road, and modules sitting at
10 are over 7.8
5 are at 7.4-something
None are at 7.7- something
None are at 7.6- something
remaining are at 7.5- something

so...my observation is before on initial build , I easily identified the bad 5 modules and 2 questionable... so replaced 7 to bring all modules to 7.7+ levels.

this time I am seeing 5 obviously bad modules and 23? questionable ones...

Should I use my charger to cycle the questionable s...and replace the bad ones?

Should I do IR tests on all modules?

Should I explore the 'rehydration' methods in some threads..

Looking more and more like this car (with abs problem ) , possible major batt rebuild, and 230,000 miles possibly needing a timing chain replace...or engine swap is beginning to look more like junk yard fodder.

Its body /interior is nearly immaculate and its such a great car...but the battery is what worries me ... Can I come out ok at all on this build...maybe the 23 modules are toast . I still have the abs issue which I am sure is just the ABS brake booster I can replace myself for less than $100...just a lot of work.

Maybe its time to drive it onto the lot where they say if you can drive it , its worth $5,500..but cant afford $300+ payments as I'm partially retired.

anyone got any suggestions?

I bought this car at $1900 tax and tags incl..with a known battery issue,...and needed to rebuild...but if this is going south ...and I have to spend $700 on modules, another $100 on abs booster (with all that labor), I cant see the savings at the end of the shopping cart compared to a conventional car like a corolla/prism which typically gets 30+ around town...with none of the unique prius problems and most any mechanic will work on it. 48+ mpg is great ...while it lasts ...but the problems (even if I do all the labor) are looking quite expensive.

Got about a year and a half use out of it, I did , at higher mpg...maybe 30K ...but looking like time to 'pay the Piper"

2003 Prius Stuck between 2 coconut trees for 3 months now, Need some help!!

jdenenberg EE Professor

jonathan T Junior Member

jdenenberg EE Professor

jonathan T Junior Member

ahmeow Prius Lover

bwilson4web BMW i3 and Model 3

jdenenberg EE Professor

jonathan T Junior Member

bwilson4web BMW i3 and Model 3

ChapmanF Senior Member

jonathan T Junior Member

Attached Files:

Getting serious about really cleaning bus bars!.jpg

Clean& Ready to install Wiring:sensor harness.jpg

Sophia having a look .jpg

bwilson4web BMW i3 and Model 3

jonathan T Junior Member

fred stein New Member

ChapmanF Senior Member

ericbecky Hybrid Battery Hero

Andyprius1 Senior Member

gittarpikk Junior Member

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2003 Prius Stuck between 2 coconut trees for 3 months now, Need some help!!

jdenenberg EE Professor

jonathan T Junior Member

jdenenberg EE Professor

jonathan T Junior Member

ahmeow Prius Lover

bwilson4web BMW i3 and Model 3

jdenenberg EE Professor

jonathan T Junior Member

bwilson4web BMW i3 and Model 3

ChapmanF Senior Member

jonathan T Junior Member

Attached Files:

Getting serious about really cleaning bus bars!.jpg

Clean& Ready to install Wiring:sensor harness.jpg

Sophia having a look .jpg

bwilson4web BMW i3 and Model 3

jonathan T Junior Member

fred stein New Member

ChapmanF Senior Member

ericbecky Hybrid Battery Hero

Andyprius1 Senior Member

gittarpikk Junior Member