Traction battery Modules replacement

[Shinner]

Hello All!

It is an Outlander PHEV but as I see it, the battery technology used is similar if not the same.

My Outlander has close to 200k miles and the battery is down to max 9 miles - it takes IN only 3.1kWh measured.

NOW, I happen to have 10 modules Yuasa LEV46 from a low milleage Outlander. (leftovers of an electric car project)

I also have MUT-III and I am planning to do the BMU reset and DBCAM after replacing the modules within the battery pack.

One thing I am not sure of is the module's CMU IDs. Since I did not label the modules from the donor car, I will certainly not place them into the battery pack in the order that the BMU expect them to be in.

I am aware that there is a function in MUT-III called "CMU ID renumbering" which *should* take care of the ID's order.

All good till I found on your forums that the CMU ID no. 7 is different than others: having discharge resistor inside. Is that true?

Is there a way that I can read the CMU ID from my modules so I can place the modules in the right place?

 

[Shinner]

It appears that CMU7 has some extra wires and the resistor in place. Or am I wrong?

 

[kiev]

All the CMU boards, and any other ecu or device that is attached to a CAN Buss, will have a resistor circuit between the two buss lines. These are required for a differential buss network to function properly.

See this post, https://myimiev.com/threads/cmu-board-notes-eprom-cell-re-numbering-can-messages.4302/post-39167, for schematic

It would seem that using MUT-III SE would allow the RESET and Auto-Renumbering functions--that would be easier than re-programming eeproms on CMU boards.

 

[Shinner]

All the CMU boards, and any other ecu or device that is attached to a CAN Buss, will have a resistor circuit between the two buss lines. These are required for a differential buss network to function properly.

See this post, https://myimiev.com/threads/cmu-board-notes-eprom-cell-re-numbering-can-messages.4302/post-39167, for schematic

It would seem that using MUT-III SE would allow the RESET and Auto-Renumbering functions--that would be easier than re-programming eeproms on CMU boards.

Yes, in MUT-III SE there is a function CMU ID Renumbering.

Would it also work if I got all the modules mismatched.
Is there a way to read the ID from my modules that I have?

 

[Shinner]

This is the CMU ID order in an Outlander pack. CMU ID6 is skipped.

If I mismatch the modules when placing them into the battery pack.
How will the software operation CMU ID Numbering know where is where? Does it have some kind of a reference?

 

[kiev]

i forgot that the CMU boards are different for miev and the hybrid, so the schematic may be different.

Check the pinout of the BMU--i think there will be pins labelled for auto-numbering. As i understand that function is intended to be used when a module is replaced in order to establish the new numbering sequence. It is a daisy-chain wiring harness and the signal travels in order from #1 thru to #11. The signal is processed by each CMU and then sent to the next in line. See the schematic previously referenced for miev circuit, CMU pins 3 and 7.

There may also be some coding of the VIN but that is only my guess.

 

[MickeyS70]

It will take more effort, but one sure way to avoid potential CMU ID issues is to keep the CMU boards and replaced the individual cells only.

Make sure they are all well balanced before swapping them.

 

[Shinner]

Yes, this is what I was thinking as my last resort.
I would like to avoid the loosening and retightening of battery terminals. 160 in total. More room for error.

I hope that this will not be needed.

 

[Shinner]

Waiting to be installed

 

[Shinner]

Can I wire them in parallel to even up the voltages?

Now they sit at average 29.65v per module and the highest is at 29.75v

 

[Shinner]

Another Idea: I could also just interchange the CMU on the battery modules with the original one in it's respective position because the CMU has one big connector going to the cells.
Meaning I would not have to dissasemble the individual cells. Am I right?

The original battery pack would then be essentialy the same - ECU wise and it should work 1st try.
Assuming that the leads and thermistors installed on the cells are the same between MY2013 and MY 2019 model year.

 

[Shinner]

@kiev: Can the CMU be disconnected from it's original 8 cells? Is there any memory or something that I should be aware of?

*my replacement modules are the LEV46, on the car they are the LEV40 ones - CMU the same?

 

[MickeyS70]

Can I wire them in parallel to even up the voltages?

Now they sit at average 29.65v per module and the highest is at 29.75v

Yes, I would recommend to do that.

 

[MickeyS70]

Another Idea: I could also just interchange the CMU on the battery modules with the original one in it's respective position because the CMU has one big connector going to the cells.
Meaning I would not have to dissasemble the individual cells. Am I right?

The original battery pack would then be essentialy the same - ECU wise and it should work 1st try.
Assuming that the leads and thermistors installed on the cells are the same between MY2013 and MY 2019 model year.

Yes, that’s what I meant by using the original CMUs.

All leads and thermistors are on the CMUs.

 

[MickeyS70]

@kiev: Can the CMU be disconnected from it's original 8 cells? Is there any memory or something that I should be aware of?

*my replacement modules are the LEV46, on the car they are the LEV40 ones - CMU the same?

Yes, only IDs matter
Compare the labels on the CMUs, should be the same.

The chemistry/capacity differences between LEV40 and LEV46 don’t matter to a CMU, however the BMU might need to be ‘persuaded’ to unlock the additional capacity, but your MUT3 should be able to do that

 

[Shinner]

I am happy to inform you that the transplant went well. - no errors and no surprises.

I replaced the modules one by one and also the CMUs.
Upon starting the car, it did not complain - I also had to reset the BMU.
Now it shows over 60km of range.

The first drive I did 55km and had still some battery left. I must say that I'm impressed with the range - around 60km it seems (on flat roads) versus the old battery range of 15km