Gen3 HV batteries for Gen2?

I still do not understand why the module(s) resistance would increase at all in a short time.

Hopefully our experts will chime in, and G3 transplants become an assured thing. It would be *great*

 

The donor car was a 2012 Prius-V with about 20,000 miles on it. I've only driven it about 6 miles so far, but it is behaving normally. The one thing I have noticed is that while the bar graph was fluctuating wildly with the old battery, it is sitting steady at 3/4 now, and I'm not sure I've seen it move it all.

I'll post more updates.

One clever thing that occurred to me is that after I removed the HV battery, I re-connected the LV battery - and then the hatch release worked when I needed to open the car to put the HV battery back in. Of course I disconnected the LV battery again before wiring in the HV battery.

 

Thats what I'm affraid. I know that the modules will fit, but how the ECU from GenII will handle them is another question that bothers me. I'm still in warranty (we can extend warranty on HV battery to 10 years with unlimited mileage here in Europe for ca.70$/year (or 12000 miles whatever comes first, but then you can extend it again again till the battery age of 10). Mine is 9 years old and doing well (110 000miles), but I'm looking for options as I'm sure it will not last forever. However the HV batteries from totaled cars with low mileage are less expensive than in the US. You can get it at around 600$, which is acceptable because except the battery the car is very very reliable.

 

There is no reason to worry about the Gen2 battery ECU having trouble with Gen3 modules. The only difference is the lower series resistance of the Gen3 modules which is a good thing.

JeffD

 

Jeff,
Any guesses why TampaPrius' attempts failed ?

 

Just a quick update - one month out and things are still looking good. Any suggestions for getting rid of a Gen 3 pack, or a set of gen 2 modules?

 

Hello Bill, any news on the battery pack? Is it still working fine?

 

Was posting earlier and saw this article and figured I would chime in. There is another huge thread about replacing the hybrid battery I added to and put alot of information about what "not to do" when performing this procedure. I switched out my modules with a Gen3 donor and have put 30k on the car and it's been working for over a year. I check the min/max voltage spread on my tablet/bluetooth obd reader every 6 months and the voltages are holding pretty steady. I had about a .20 volt difference on install and around a .25 difference now. The car will throw a code around the 1 volt plus mark differential. The car can go a long, long time, in stop and go traffic without discharging compared to my old gen2 pack I replaced. I can leave it sitting for a couple of weeks on vacation and hardly any discharge on the hv battery. Basically it's take cells from Gen3 pack and insert into new pack and that's pretty much it. Don't get fancy with it because the cells are probably perfectly balanced from the last time it was charged so no need to go through all that unless you are replacing an individual cell, which you aren't. Just be smart about it and read the huge install thread on these forums. It'll be the one with probably a hundred pages at this point. Make sure to read my "what not to do" section I would have saved myself alot of time if I didn't screw up one of the cells by shorting it and testing another one the wrong way and drawing power from it.

 

Gaylon thank you very much for your contribution, I really appreciate that! ;-)

 

My search failed. Could you post a link to your other post ?

 

Here's the link Sage, Gen II Prius Individual Battery Module Replacement | PriusChat

 

Rather than skim 40 pages, I thought "this is easy. I'll find Gaylon's posts in the thread."

And .. the search comes up empty!
Did you post under another name ?
Either that, or I am being stupid or PC is having 'issues.'

Perhaps you can link directly to your post ?

 

I'm also having troubles finding his post, probably he used another nickname..

 

Just one quick question .. could be batteries from Prius V (or Prius + should I say) also used as an replacement for Gen2? Or are they different from Gen3 modules? Thank you

 

Well do you mean the Prius V OR the Prius + as they are two very different vehicles despite looking very similar.

The European Prius + uses Li-ion technology and the smaller HV battery is between the front seats - hence why they can squeeze two extra seats in making it a 7 seater. The US Prius V uses traditional NiMh battery tech in a similar way to the Prius. It might use the same HV battery.

 

Oh, ok thank you for the explanation. I meant European Prius+, so you have saved me a lot of troubles. Thanks again

 

You're welcome.

 

I read the thread “Gen II Prius Individual Battery Module Replacement”. 40+ pages…took a while. Some parts of it I have read three or four times and even printed some of the posts for future reference. My sincere thanks goes out to John(Britprius), Eric(ericbecky), JeffD(jdenenberg) among many, many others. You seem very knowledgeable and show a sincere desire to help others. You have encouraged me to jump into working on the battery pack of my Prius.

I own a 2005 Gen2 Prius with about 145000 miles. My son has been driving it in Los Angeles for about a year and a half and in early May it developed what was dealer diagnosed as a bad HV battery pack and a bad 12V auxiliary battery. P0a80, c2318, c1253. New battery pack at $3300, new 12V at $300 both prices included installation. I had replaced the 12V with an optima in 2008. At that time there was no optima direct replacement with the “pencil” posts so I bought a kit from someone to make the conversion possible. As luck would have it, the person I had bought the Optima conversion kit from is in Sylmar, CA, a suburb of Los Angeles and only a few miles from where my son lives. He has a service that replaces bad modules in Prius HV batteries and he came to my son’s house to do the repair. Cost was $450 which includes up to 5 module replacements and $40 for each one after the first five. The repair was done, one module was replaced, and the car is now back on the road. I don’t know what the process entailed but it was made very clear to me that this was a shorter term fix rather than a longer term one. 6 months to a year vs two to three years. Seemed to be an honest guy who was concerned that my expectations not get too out of line with reality. Based on his findings, he did tell my son the HV battery probably still has a lot of life left in it, but nothing that can really be guaranteed. Don’t know how he made this assessment. I was just glad for my son’s sake that the Prius was back on the road.

I have been waiting for this battery pack to go bad because I was really looking forward to learning how to replace the old one with a new one. But the car was in L.A. and I am in Scottsdale, AZ so I just didn’t see that happening. But after reading the Prius Chat thread, I would now like to replace bad modules with good ones instead of just replacing the old battery pack with a dealer supplied new one. And if I’m going to be replacing modules, I may as well completely replace all the Gen2 ones with all Gen3 ones.

I can take all the time I want. I have an air conditioned garage to work in, almost a necessity here in the Greater Phoenix, AZ area, and am retired so I can take all summer if I wish. I rebuild old Volvos and am a pretty fair garage mechanic. My budget process works something like: $3300 was the dealer solution less $450 repair and $118 dealer diagnostic leaves quite a balance for a used Gen3 battery pack and whatever chargers, high voltage gloves, insulated nut drivers and anything else that may come up.

So I got the Prius back out to Arizona and bought a used Gen3 battery pack and have been working with the modules for a couple of weeks now. I am using (2) X4-80’s and an “ePowerBox 30A” power supply (540 watts), both by HiTec. I started out with one X4 and quickly realized that it was going to take at least two of them to get this done sometime this lifetime.

I started out doing a load test using an automotive headlight. I used an older DMM to measure amperage and a newer DMM to measure the voltages at the end of the load test and just as soon as the load was removed from the module. See the photo of the setup I used to do the test. The white switch is just an old wall switch I had in the garage and the headlight is a high/low headlamp from an old Volvo. The load is 55w+35w or 90w total.

I really don’t think I did this part correctly. Capturing the amperage reading was easy. But the voltage readings were moving pretty quickly during the test. I used an iPad timer (one minute) and caught the voltage at the end of the test, “V1-end load” is how it is labeled in the spreadsheet that I have used to try to compile the data collected during the load tests and during the module cycling. At the end of the test I opened the switch to remove the load and then recorded the voltage, “V2-end open”. During the first test, I did’t realize that my new DMM had a hold feature and the voltage readings were at best an approximation. During the second test I was able to press the “hold” button on the DMM as soon as I opened the switch to end the test and the readings were a little more reliable. Having said that, when I looked at the data I collected, there are some readings in the second test that I cannot make sense of while those of the first test seem to make a little more sense.

Also, in post #604 by John(Britprius) of the thread “Gen II Prius Individual Battery Module Replacement”, there seemed to be a bit of a different methodology than the one in the post immediately following, #605 by (uart) and in post #5 by Marc(marcs_carhole) in the thread “Prius Battery Rebalance”. John seemed to suggest reading the voltage used in calculating the internal resistance before the load test and uart and Marc seemed to suggest reading the voltage immediately after the load test. I tried both and got such different results, that I just went with uart and Marc. The results seemed a little more in line with what might be expected.

I would really like some help on this point. The load test process was for me the most problematic aspect of what I’ve been trying to do. And I think it may be one of the most important. I am less than confident in the results of my tests. The first test was done before doing any module Dchg>Chg cycling and the second test was done after the first sets of Dchg>Chg cycles were completed. I’ve tried to lay out the chronology in the way the spreadsheet has the various load tests and series of cycling labeled using the dates showing when things were done. Sorry for how cumbersome the spreadsheet has become, but it seemed like a good idea to try and bring as much information as possible all together in one place. At least it seemed like a good idea at the time.

The Dchg>Chg cycling seemed to be a little more straight forward. I had a tough time tracking down exactly what the program variables should be, but after reading many, many posts, I found that the areas of concern were the current limit, delta peak and capacity cut-off. Thanks to everyone who posted the settings they used. They were really, really helpful.

I decided to stay very conservative and hold the current limit to 2.0A. I did this mostly to keep heat buildup down as heat can be a real problem in the Phoenix area. The first sets of cycles were done during an unusually mild part of May, but I still registered temps of 99F (module #15) during the very last phases of a charging cycle. Adjacent cells were 86F and the garage was at 81F. My evaporative cooler was not on. I turned it on and 15 minutes later the module read 97F and the garage 79F. No effort was made to specifically cool the modules at this point.

Delta peak was left at default which is either 5mV/cell or 7mV/cell. Couldn’t really tell. I believe this setting was responsible for some of the problematic readings encountered during these first sets of cycles. This was changed to 20mV/cell for the later sets of cycles after reading post #634 by John(Britprius). He also suggested a time limit cut-off but I didn’t have clue to what it should be so I just left it off. In later post(s) it was suggested to set this to 720 minutes and that’s probably what I’ll do going forward.

Capacity cutoff was initially set at 7500mAh based mostly on the reasoning of John(Britprius) in his posts covering this setting. I later changed this to 7000mAh at the same time I changed the Delta peak thinking that this may have been too high based on settings used by others that seemed to meet with more success than I was having. If I had it to do again, I would have left this at 7500mAh. I now feel that the improvements I saw in my results were due to the change in Delta peak. In fact, I may have done a disservice to myself by lowering to 7000mAh by not getting all the capacity I could have into the weaker cells within the modules. Don’t really know how to test for this other than by running another set of cycles and I don’t really want to do that unless someone thinks that it could make a significant difference in the capacity I ultimately wind up with.

The last setting that I addressed was the discharge amperage. I had initially set it at 1.0A thinking it would take a little less time than a lower setting. I’m still quite fuzzy on this particular setting and didn’t know if it was adversely affecting my results or not. So I lowered it to 0.7A which seems to be the norm on most of the posted settings if I remember correctly. I have thoroughly given up on doing this process quickly so if things take there own sweet time, that’s just the way it’s going to be.

It may just take all summer, after all.

So I’m now in the final process of re-running cycles on modules 2,4,6,8,10,11,14,17,18,19,21,22,24,26 using the revised settings. Any module that returned a Dchg capacity of less than about 4600mAh after 3 cycles was chosen for a rerun. 4600 is a completely arbitrary number that I just felt right about after looking at the results of the first sets of cycles. And after looking at the results of the latest sets of cycles, I may want to revive that up a little and at the same time change the capacity cut-off back to 7500mAh. I’m a little worried that I may be running too many cycles and somehow affecting the longevity of the modules. But what the heck, this is a learning experience as much as anything else. So reduced longevity at the expense of learning something worthwhile is a good trade. Hopefully, someone with expertise can help guide me a little here. My lowest Dchg capacity of the latest reruns is 5228mAh (module 10). What I don’t know is if this reflects the health of the least healthy cell in the module or if it’s a reflection of something else. I tend to think it’s not a reflection of the least healthy cell in the module. But again, maybe someone can give me a little expert guidance. I would certainly appreciate it.

My last question concerns the return of a Dchg number at the end of cycle 3 that is just slightly lower than the Dscg number of cycle 2. I’m not quite sure how concerned I should be about this. And I can’t even begin to outline any sort of reasoning for it. My impulse is to think it’s important but without knowing its cause or what to do about it, I’m stuck.

Sorry for the long, drawn out post. I hope I’m not violating any rules. But I’ve never posted on any forums before so I’m quite the NOOB at this. It’s just that so much territory is covered during the module “reconditioning” process, it’s hard not to be overwhelmed at times.

I’m posting this to the Gen3 modules in a Gen2 Prius because that’s my ultimate goal. If it should go somewhere else, would someone please let me know?

And once again, my very heartfelt thanks to everyone who has taken the time to help those of us out who otherwise wouldn’t know where to turn next. You really make a difference.

 

Not quite sure how this works so please bear with me.
I also posted the above here:
Gen II Prius Individual Battery Module Replacement | Page 45 | PriusChat
in post #885. I did this because the first thing I must do with my Gen3 HV battery before placing the modules in my Ggen2 is recondition the modules and this thread is where I originally found that such a thing was even possible. There have been some priceless replies giving me great information on how to proceed and why. Can't believe the knowledge that some of these kind people display. Very humbling.
Anyway, if you want to see more information concerning this, please look there.
John

 

Its been over two years since I put 2010 cells in my 2004 HV pack, still working fine. I felt for myself, simply switching was safest.
Replaced 2004 HV battery with a 2010 salvage one | PriusChat