Juanjo Madrid 's cell replacement thread

[kiev]

Moving the discussions related to @Juanjo Madrid 's cell replacement to it's own thread:

Cell and module numbering:

Is correct this?, I open now my battery, and cell 88 of CMU12 is connected to 77 cell of CMU 11 with this numbering, how see this I find more informaton and see other different numbering in this forum? I use OBDZero and I´m checking cell 86 because this go to 2,86V when push full acellerator.

 

[kiev]

Yes. the most positive cell of the CMU11 module connects to the most negative cell of the CMU12 module.

Please share links to other posts with different numbering so we can clean this up.

This numbering and lettering is as used in the Factory Service Manual and by the canion app. i don't know about the numbering scheme used in OBDZero.

Good luck to find and replace that weak cell, hope you are successful.

 

[kiev]

@Juanjo Madrid
I think it's not the cell's problem, but the CMU12 contact's

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I think it's not the cell's problem, but the CMU12 contact's

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[kiev]

@Juanjo Madrid
This is my read values when full trottle

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[kiev]

I think it's not the cell's problem, but the CMU12 contact's

@MickeyS70
If that were there case your cell voltage would be off at all times, not just at full throttle (the contacts are just for voltage sensing).

True, it could also be a CMU fault but it’s more likely to be a weak cell and there seem to be a few in your pack, unfortunately.

What does the balancing look like at low SoC without load?

 

[kiev]

Use your voltmeter to check the cell voltages to compare with the scanner values--is the difference real at the cells, or just in the posted values?

The corrosion or fretting of the gold plating of the cell monitoring contact pad is quite a puzzle. Can you determine if it is corrosion, or if a broken pad?

i agree with @MickeyS70 about the intermittent vs constant nature of a faulty reading.

Those low cells would definitely drop under high acceleration and might trigger the turtle mode.

 

[kiev]

@Juanjo Madrid
With SOC of 35% , all cells look balanced with little differences of 5-10 mV, only with full trottle or large hills show the turtle when the 86# go to 2V8. This cell have the same IR (2,4 mOhm) and similar voltaje of near pack cells. I buy two LEV50N in China and have 1 mOhm and around 36Ah, I put in 86-87 and tomorrow test the car.

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[kiev]

@MickeyS70

Make sure that new cells match the voltage of the others within 5-10mV also, otherwise balancing will take a long time..

 

[kiev]

@Juanjo Madrid

Kiev, the cells voltaje is similar to other cells, when standby, in OBD and with voltmeter all balanced, for this I need locate the real cells number in my model, I see your diagram and not match numbering with my real cells position, my car is Left hand drive I-miev. Reading the voltage in all the cells of pack are similar now, not differences.
I think it's corrosion due to different alloy and metal joints or maybe friction due to loosen bolts (was easy to exit), the bottom of the bolts looks perfect, but the copper pads (¿gold plating?), look bad in the screw washer contact area, I open also the 40-44 CMU6 cells, and look better than this 85-88 cells CMU12.

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[kiev]

@Juanjo Madrid

Whats think about this numbering?

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[kiev]

image of cell layout


@Juanjo Madrid
With this numbering my + 77 cell is connected to -88 cell, and -44 to +33, not is a confuse with OBDZero app numbering, is the real connections on my battery compared with this diagram.
Differences LHD and RHD cars?

 

[kiev]

i don't believe that there is a difference between LHD and RHD. It would cost too much to make different pack configurations with no benefit.

Whats think about this numbering?

Are you thinking that the cell numbering that you labelled corresponds to the OBDZero numbering? i don't know anything specific about how that app numbers the cells, but i would guess that it is the same as Canion since it is reading data from the CAN Buss IDs

The pack with the yellow cells looks to have the same layout as the diagram i drew, The most positive cell is #85 and the most negative cell is #8. You can check with a voltmeter that this is true.

 

[kiev]

@MickeyS70

There is a difference between LHD/RHD HV packs but this is due to the fact the AC ducting is on the other side and changes were done accordingly (lid is different), however as @kiev pointed out, electrically they are the same.

 

[kiev]

Whats think about this numbering?

@MickeyS70
Just disconnect the CAN plug to one of the 4 cell packs and see which one is missing in OBDZero. Another way to identify a single cell is to swap it with one that has a different voltage (your new ones?).

BEWARE: do not just disconnect a cell on the CMU board as this may blow the corresponding SMD fuse on it when you reconnect your 12V aux

 

[kiev]

@Juanjo Madrid

Not match "real connection and the diagram". This tread of this forum confirm my numbering, almost sequence need be like this, if follow connections (White busbar covers), to connect again OBDZero with Can bus disconnected, need Up the package and again go down, I have limited resources and time, I work in exterior with bike elevators, I think the 86 cells is in 50% the marked in my drawing, not have voltage differences. Go to put today with used LEV50 N cell and cross fingers

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[kiev]

@MickeyS70
I have replaced CMU12 where cell 86 is located myself, it’s physically located on the right hand side of the pack; therefore if you use your own numbering in post #19 you will be swapping cells out of CMU06…

 

[kiev]

@piev

Looks like you have it backwards. the cell you mark as 52 is cell 1. the cell you mark 41 is 88.
in your photo module 1 is the top left module. Module 5 is the top right module.

 

[kiev]

Malm's diagram was not correct when they went to change a cell.

the link to that post,
https://myimiev.com/threads/single-lev50-cell-wanted-for-our-citroen-c-zero.2720/post-23597

That is in Martin's (me68) cell swap adventure thread, the first done here with a time lapse video showing the process.


The first time in they replaced the wrong cell due to using Malm's diagram (which is also the way that you have numbered the cells in your picture), then they checked the cells to find the correct location for cell #23, shown in green here (view is from the back right corner of the pack)

 

[kiev]

Malm's diagram was a guess that he made without seeing inside a pack.

@Malm said:

Congratulations me68. For me, it was a surprise, the location of the 23.

@kiev asked:

Was the cell located where you expected it to be in the pack? The diagram from Malm looks like a different placement for cell 23.

@me68 replied:

No - it was in the 8er module in back, not in the front, as somebody has shown us.

@Malm:

So, I will have to think about this again.

to which @me68 said:

Hello!
Please not! If you know it, please tell it. If not, it's only a sneaking suspicion from you.
Martin

If you follow Malm's diagram/your numbering, then you will learn the hard way how the cells are numbered.

 

[Juanjo Madrid]

Ok, Im now balancing cells, in two days put again in the car, I put here how result.
Thank you for help me....