Gen II Prius Individual Battery Module Replacement

so, i discon the battery (12v) several minutes and upon reconnect and start whalla, read triangle is gone, no codes adn no shutters when engine running, soc 59 engine shuts off , i put it in d and r a few feet and all seems good --- i will button things up well enuf for a test drive before further buttoning up the rest ( the whole rear interior is taking up alot of garage space () .....

one funny thing is the csd shows 0.0 , -- which is not good, it is not possible that there is no deviation between cells so % difference in SOC, that is supposed to show the cell difference and there is always some, perhaps the code is not entered properly ...

also, i used alcohol (isopropyl 70%) and an old brushhead on an electric toothbrush to final clean the terminal surfaces, i did torque them to about 48" pounds manually.

with any luck i am back in business, i have a local source for more modules should the occasion arise (hopefully at least several thousand more miles) and i'll not be using the ev button much and ill be watching that soc alot more as well ...

Thanks to everyone who contributed for your help , input and suggestions! It definitely would not have gotten this far this fast without you !!

 

So , got enough buttoned up (saving the seats and one side panel and spare tire and associated parafinalia), that I took it for about a 2 mile round trip with a stop in the middle. only thing i'm getting is mait req, which i was getting check engine light before due to an oxygen sensor either broken or connection bad on the exhaust before the 1st cat .
i did get a u0111 and still get a p0000, the u doesnt come back but the p 0000 does and mait req and check engine still there -
not getting much heavy shuttering effect and now i am ready for a 10+ mile round trip , with multiple stops . man it will be good to take the gas hog (3l v6)back as i just have to fill it up aagain one last time ..!!!

 

!!! So, I'm wondering because you mentioned it, should the Velcro be on the inside or the outside of the gloves, or both and why? I can't imagine how I would be able to pick up a battery nut with Velcro on the fingers.

 

after aabout a 15 mile round trip, with 3 stops, the only error code is the 2238 which i was getting before the battery problem so it is good for the while --- i recommend anyone with a highmileage car to not park the car with less than a 50% charge, somehow, when it is that low and its cold and going , the charge drops more andwhen it starts getting to 40 , 30 then 20 - you enter that range where cells can get deeply depleted and reverse polarity

 

<< Tests batteries with toy chargers and loves it

 

probably have some capacity but high self discharge, failure is pending for these modules but they might hang on for a bit longer give them a chance (check 1 and 28)

this is why you cant test a full pack in one hour no matter how good you think your tools or skills are

 

According to my experience with the DTC codes, the thirteenth pair of modules is near the end with the computer or ECU unit is located.

Apparently the Japanese engineers decided to start with the first block or pair being the end where your letter paper is. They built the battery up until the last (#14) block at the end and then added the connection to the ECU and the cable to the motors.

Think of it as going from zero (1) to 220 Volts or 14 blocks as you go from the bare end of the battery to the connection. For Americans, it might seem counter-intuitive but the highest voltage on a 12 Volt car battery is at the terminals.

Usually Prius Chat posters will qualify how they are numbering ("enumerating" for the math geeks)
their modules. They usually number the modules individually from one end or the other. Takes a bit of discipline to keep it all straight, so I made myself a small spreadsheet to keep it straight. This helped me to pair my modules to their respective mAh and then re-number them for reassembly.

 

If the writing on that warning sticker on the top clamp rod is not upside down I start the count 1-28 left to right

that's how I remember it because batteries not always in pack when im messing around

 

I tend to agree but I have to ask (rhetorically) whether there is a production or engineering (design) quality problem that has not yet been solved. Production demand for many of these products (cell phone batteries and "air" bags) is such that eventually there will be a bad production lot

There is hope, however. Battery characteristics in general could change significantly if the reports about the use of carbon nanotubes in battery production can be realized. Also, super-capacitors or similar solid (state) chemistry devices may eventually replace batteries as we know them. Capacitors have traditionally been more robust than any chemically active battery and they charge and discharge at very high Amperage rates. Experimenters and DIYers have been using supercaps to charge, augment and even replace lead-acid batteries for several years and there are already many portable auxiliary battery chargers/car-starters in the marketplace.

 

I also tried to clean the nuts with a (lethal) combination of cleaners (distilled vinegar, Zep505 and hydrogen peroxide - don't try this!) but only managed to add my own brand of corrosion with the washers falling off.

I ended up buying a set which had very little corrosion so I just used a piece of 400 grit wet-or-dry sandpaper to shine up the rim of the washer and ran the nuts through with a handy thread cleaning tool. Although the greenish corrosion was easily removed, no chemical I was willing to use would remove the dark brown oxide coating on the copper bus bars. I used a Dremel sanding tool to remove what appears to be copper oxide and I have to say that it's tougher than rust!

 

It has been posted on this thread, more than once already I believe. I would have to look it up. First two digits are the day of the month. Third is the month with X, Y and Z being October, November and December respectively and the fourth character is an alphabet letter that is A=1999, and so on. The other digits and characters seem to be a serial number but there is usually a letter at the end and it may be followed by B1, B2 or B3 - at least those are the ones I have seen.

If someone at a Panasonic factory would care to reveal what the characters mean, it would be good to know. So far, in my limited experience and reading, the B-digit modules don't seem to be doing as well as the ones without, but that's only the 37 modules I have handled and attempted to charge.

I did read that Panasonic production capacity was supposedly 500,000 per year but that seems to make the numbers of Prius sold, being more than that per year, seem false. More recent news has Sanyo also sourcing the batteries but their production was quoted at about 10,000 per year. This, and the general robustness of Toyota's vehicles, could explain why the batteries alone are so expensive. YMMV and FWIW.

 

lol that hasn't happened to me, good effort! only tried to clean nuts once and all the zinc coating fell off and left me with shiny silver rust prone nuts and a jar full of yellow flakey chunks of zinc floaties so I cursed a little then chucked them away. Can buy zinc coated serrated flange nuts online for a few cents each and they are very similar to what Toyota use these days, I will be buying these when my stash of clean used nuts runs out! there's no way im messing around cleaning stupid nuts if can buy new ones for about 10c each. Toyota revised the nuts a couple times over the years only XW11 and XW20 prius use those stupid "spinning flange washer" style nuts, early XW30 use a larger solid nut with a flat flange and later years of XW30 and priusC etc also use similar but with serrated flanges.

yea the copper bars are challenging too lol but if you mess about for a while they will clean up like new

 

I agree, the copper bars do require more "elbow grease"!

I'm curious about the nuts you mentioned, having paid about $0.50 each for used ones, albeit they are in very good condition. The hex part of the nut is 8mm and the thread size I have forgotten. I have already replaced two of the 10mm nuts in the relay cage with nuts similar to your description of the later Prius "C" nuts with the serrated flanges.

The torque specifications from the TIS are difficult to relate to specific nuts and bolts as well; I ended up torquing all the nuts and bolts for the modules in my Prius to 66 in-lbs. I discovered the 48 in-lbs torque while re-reading the hv battery torques page after I had already secured the battery in the vehicle. I am still not completely sure I know which torque applies to which nut and bolt because I have yet to find the diagram which relates the name to the particular nut or bolt.

On the other side, my torque wrenches are the "click" type and very old (ca. 1980's?). They spent years (decades?) with settings at 175-200 in-lbs before I realized that they should be set at zero when not being used. I have never calibrated them to an official standard so all I have done is try to get them to agree with each other.

 

50c each for USED NUUUUTS dude you got %*#&$&kd

I wont link exact items as I don't want to be responsible for linking something that might not be correct lol

BUt the ones I was looking at are 5mm / .8 pitch serrated flange, heaps on ebay in lots of 100 for about $10au so they will be even cheaper for you

im pretty lazy with torque wrench ..I mean they give torque settings for installing a wheel !!! for the 12v battery clamp

 

Heads-up boys, re: "nuts": keep the module' nuts (M5-Socket8) from NHW-20/NHW-11 as you would need them in the future, working on the newer Prius. Nuts there have cone shaped sides and even awesome and very strong "buldog" connectors (made in Japan) I use could slip from those. So replacing to the normal flat side used in older models could be handy.

 

Chargers tend to prematurely terminate when leads are clipped to the zinc coated nuts.

Always remove bus bars and nuts when working on individual modules.

 

Took me 6 months but I only had one Hitec X4.

 

This is good to know.
Please post ("before & after") photos if you can! It would also be good to know if there's any different nuts being included on the U.S. Prius.

 

please forgive me

 

Took out hybrid battery and measurements go like this in volts...
Day 1: All 8.29-8.34 with one bad one at 7.76
Day 2: 8.10-8.14, bad one 7.20
Day 3 8.00-8.04, bad one 6.80

Does this sound normal? Is letting the battery sit and reading the voltage everyday an indicator of health?

Thanks