How to get this 62kw battery balanced?

[Daveblackburn]

Hey, I got my second leaf, first one was a 2013 many years ago, this one is a 2020 sl plus
Had it about a month, still had leafspy pro from the first leaf.
Apparently the battery in the 2020 had a few cells replaced under warranty 6 months ago. I don't have any documentation for this.
Car gets great range, 95% soh, but a large chunk of cells are 70mv different.
Any ideas how to get this balanced?
I've read all the threads, left the cart at 100% plugged in all night, no difference.
Thanks, Dave

 

[cwerdna]

You mean 62 kWh?

 

[OrientExpress]

One way I found to keep the cells all balanced with each other is to periodically charge the car to 100%, then charge it again, and then again. 3-4 charges after it is at "100%" . This will cause all of the lower charge cells to balance up with the other cells.

 

[GerryAZ]

Show us a screenshot when deeply discharged. 70 mV difference is not that bad for a 62 kWh battery. It will probably balance the cells over time by just driving and charging normally. The voltage difference will vary depending upon state of charge.

To put your numbers in perspective, I had 303 mV difference the last deep discharge test I ran in February (254.77 volts at the point of low voltage shutdown). The difference was 10 mV at 403.46 volts (full charge) after charging overnight. I had 78 mV difference at very low battery warning a few days later. I had 22 mV difference at about 70% charge recently.

 

[Stanton]

To put your numbers in perspective, I had 303 mV difference the last deep discharge test I ran in February (254.77 volts at the point of low voltage shutdown). The difference was 10 mV at 403.46 volts (full charge) after charging overnight. I had 78 mV difference at very low battery warning a few days later. I had 22 mV difference at about 70% charge recently.

But, but, but: your pack was properly top-balanced (when fully charged). When replacement cells/modules are inserted into a pack that is not properly top-balanced (like this one)...they never really recover (trust me, I did it).
The forum administrator needs to merge the OPs 2 threads...because they are essentially identical and I answered him in the "other" thread. I think this one originally got derailed by @cwerdna's usual "kW vs kWHr" post (which had nothing to do with the OPs question and threw him for a loop).