Help identify location of faulty battery cell

Hi all,

I'm getting the turtle mode signal when under load with the battery still half way full and using a scanner, I found the following code: P1A2F

Looking at the cells voltage under load, I identify one that is going down to 2.6 V when the rest remain over 3.4 V. In the scanner, the cell is identified as 3-B for pack 3 and cell B.

I have found someone on ebay that sell used LEV50 cells. So I was thinking of replacing the faulty cell.

Is there a way to identify exactly where in the pack the 3B cell is? Do we have a diagram/schema of the iMiev battery pack to identify the location of the cells?

Also, is there a way to apply load to a cell, or maybe 3 cells to have 12V, in order to test them when they are removed from the battery pack? I would like to be able to test the faulty cell to make sure I replace the right one. I would also like to test the one I ordered under load before I add it to pack. I also want to charge/decharge it to the proper voltage to match the rest of the pack.

Do we have a procedure to follow in order to remove the battery pack from the car?

Any help would be greatly appreciated.

Thank you

Howdy and welcome,

Take a look at this thread for some info:
https://myimiev.com/forum/viewtopic.php?p=45469#p45469

and a video
https://youtu.be/CbeY2dOg5tY

high speed
https://youtu.be/YcL4UvGvWkA

JFC said:

Also, is there a way to apply load to a cell, or maybe 3 cells to have 12V, in order to test them when they are removed from the battery pack? I would like to be able to test the faulty cell to make sure I replace the right one. I would also like to test the one I ordered under load before I add it to pack. I also want to charge/decharge it to the proper voltage to match the rest of the pack.

Click to expand...

Hi there
With the link provided by Kiev you should be able to identified the faulty cell in the pack. You’re right, it’s best to match the voltage as close as possible to the remaining cells, but equally important it should also be similar to their remaining capacity (weakest cell defines the whole pack) Ask the seller or better use a hobby RC charger to measure and charge/discharge your ‘new’ cell.

Testing under load means you need to pull a constant current of 100-150ADC while monitoring cell voltage. You could put 3 or 4 cells in series and connect them to a 12V 1500W inverter running at full load.

You can’t mix LEV50 (cars built pre 2013) with LEV50N cells and some versions (colour of cell) of LEV50 have slightly different keyed terminals, unfortunately there is no way of telling what is in your pack until you open it.

Last but not least, I would highly recommend to use a car lift to remove the battery and an impact wrench works wonders with rusty bolts.

Hi all,

There is a Peugeot iOn with 80 cells, a sister of Mitsubishi iMiev.

I have seen the great drawing of Kiev of the iMiev pack with 88 cells and 12 CMUs identification.

But has someone the drawing to identify the cells and CMUs for this pack made by 80 cells (not 88) and 10 CMUs (not 12)?

I guess there are not the 2 x 4pcs cells (CMU 6 and CMU12) but how is, in this case, the cells identification and CMU numbering?
Thanks to all in advance will help me.
Sandrosan

Hi
You are correct, your car doesn’t have the 4 cells CMU6/12. I did come across a diagram a while back but can’t find it any longer, from memory it just continued the sequence in 8block sections..

MickeyS70 said:

Hi
You are correct, your car doesn’t have the 4 cells CMU6/12. I did come across a diagram a while back but can’t find it any longer, from memory it just continued the sequence in 8block sections..

Click to expand...

Thanks a lot MickeyS70

Hi,

Exactly the information I need to proceed. Thank you all. I did the job with my brother who has a lift Yesterday everything went according to plan.

I replaced cell 18 that was dipping under 3v under load and causing the turtle mode. I bought the used cell to replace it from an ebay seller located in Québec:
https://www.ebay.ca/itm/294864353952?hash=item44a748faa0:g:9lkAAOSw6F1iL7ic&amdata=enc%3AAQAHAAAAkM7ARKBRNFBEKPnBxFeIDkTR5R49rUoSKab020vc%2BsaS2iM82SrNXvrsAOChwuHTpvPnVtU5co2rQmJt6%2B0v8f7xrOnVgsH6WJ1jI%2Bv6Dob%2FR4tWxQEKTFTEfq%2FVCFI30giML2t4PgtQgNKpdZ%2BN%2Bn%2FA2SN8pCOYjD6olwJFR7EG7EsYk15R%2F%2F7iSOsxjrWs%2Bg%3D%3D%7Ctkp%3ABk9SR7i-jYK8YQ

The only option offered by Mitsubishi was to replace the whole battery pack for 19000$ + taxes. It took us about 8 hours, 65$ for cell and case of beer, no more turtle mode.

So for anyone facing the same issue, consider this approach, it will be worth your while.

Do not forget, before you do anything, unplug the 12v battery and pull the main battery plug from under driver seat to block any battery load from getting out the pack, then you can safely unplug everything before dropping the battery pack.

Well done, curious to know how does the ‘new’ cell affect the range as it’s useful capacity is less than stated?

I have the same issue and would be interested n an update, please...?

Getting my scanner soon, same issue on one of my Mievs - battery is half full and pushing flat out the turtle appears. Range is a mere 50kms only. First of trying to get a better view with the scanner of how many of the cells are out of order and how many are nearing their life cycle. Planning to replace the faulty ones. If the there's too many of them, then... the whole pack if needed.

riburada said:

Getting my scanner soon, same issue on one of my Mievs - battery is half full and pushing flat out the turtle appears. Range is a mere 50kms only. First of trying to get a better view with the scanner of how many of the cells are out of order and how many are nearing their life cycle. Planning to replace the faulty ones. If the there's too many of them, then... the whole pack if needed.

Click to expand...

A low range in general can have multiple causes while the appearance of the tortoise during high SOC usually points to a weak cell(s)

Depending on the age your triplet you can either access individual cell info or only high/low cell data,

First do some (stationary) checks in READY when fully charged: find the battery pack capacity value, then look at cell voltages while idle, afterwards turn on heater, lights, AC, fans etc and check again.

Next get a buddy to drive and try to make the tortoise appear, take note of any cells below 3V when it does.

Finally with capacity down to 1-2 bars repeat stationary checks again.

If you have access to rapid charging (CHAdeMO) plug in and monitor cells, bad ones reach 4.1V faster and usually get hotter than the rest.

Last but not least be aware that bad performance isn’t necessary a cell issue, problems can also be caused by faulty CMUs (Cell Monitoring Unit monitoring 4/8 individual cells).

Let us know what you find.

Mickey