Can't mix yellow and purple

[danielk04]

I had two weak LEV50 cells in my pack of eighty-eight. I traveled to the far away land of Canada to purchase an eight pack LEV50 assembly. His were yellow in color, mine were purple. Imagine my surprise when I saw that a yellow cell is taller than my purple. Yellow and purple mixed in the same four pack box don't fit. The plastic (pcb) lid won't fit on the mixed four pack case.



There is a work around.
Replace your one bad cell with four yellow cells using the yellow cell plastic box and lid.
Don't forget to transfer your original (purple) BMS board to the new (yellow) assembly.
That will leave you with three spare purple cells for future use.
I can provide more detail on the battery repair if requested.

[url=https://ibb.co/7nPGGWn][img]https://i.ibb.co/x1WMMj1/20220131-121016.jpg[/img][/url]

 

[JoeS]

Danielko4, thank you so much for posting your findings. Yes, I'm sure a number of us are interested in your solution as it sounds as though you replaced the entire module with its four yellow cells and stuck on the original BMS board and it all fit!

We need to be building up our body of knowledge as our cells wear out and we need to know how to replace cells and subassemblies and not just entire packs.

Edit: Also, we need to understand the technical differences between the yellow and purple cells. Anyone?

BTW, testing to see if your photos are available using only the bracketed Img without the bracketed URL. Hit the quote response to see what I did.

 

[stoatwblr]

There are blue ones too

I'm assuming the colours mean differing chemistries or constructions as I'm seeing a consistent 40mV difference between blue and yellow ones (which is out of tolerance)

We need more technical data from yuasa about these things

 

[jalovick]

I went the other way around without any issue. The cells in the pack of my 2013 i-MiEV are yellow and one failed. I contacted a conversion shop that does battery upgrades on the i-MiEVs, and they sent me a purple one. In the plastic carrier, there are little tabs at the bottom that holds the slightly wider purple ones high, but allow the yellow ones to go to the bottom (I think I remember which way around they go correctly). Anyway, after balancing them together and reassembling the pack, after a few charge cycles I've managed to get my range back up to around 85-90 Km, compared to it dropping to 50 Km and then not even starting up when the cell finally gave up. Here's a pic of when I test fitted it before re-assembly.

Back in the pack...

Jamie

 

[kiev]

Thanks for sharing the photos Jamie, is your car RHD?

What is the spacing between the modules when installed in the pack--what would you guess might be the available gap for using a slightly taller cell? Is there any "unused" space between modules?