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[Doctorbass]

 Few month ago, i had measured my 2011 DS battery that i suspected to have a low bank. I had discovered that at the end of the dishcharge ( when one or more cell bank reach the low voltage limit)  there was 400mW difference between this low bank while all the 13 other bank was all the same voltage ( 400mV higher)

Today i fully disshcarged my zero down until the battery cut ( fortunatly i was only 500m from home). I measured only 56.6Ah . Last year i had measured 59.7Ah. and the low cell bank that is still the bank no 1 is now 500mW lower. It droped by 100mV  from last year...
( see the attached picture of the MBB data i grabed:

Well i have to say that dissassembling the battery another time willl be a pain .. i have spare cell bank that's not the problem.. the problem is that i know i will make more improovement and that the battery will need to stay few days on the bench even if i open it again...  this mean no motorcycle ride ...

Unless i use the lazy solution.. wich consist of  connectin a parallel LiMn cell  with the same missing Ah than the low bank have to this low bank. ( fortunatly last time i opened it i have installed 30A anderson connectord for each of the 14 bank to be able to fast rebalance or monitor them...

Well at least i have two good solution... until i decide to begin the real big project ( upgrade to 100Ah 84V but keeping the actual battery)

Doc

[ed5000]

Sorry to hear about that Doctorbass.  Don't you have a Cellmate meter that reads out the voltage of each cell?  I would think that if you had a weak cell in the one bank you should be able to see it.  Other than that can you use it with your booster pack until there's a better time (like winter ) to do a tear down?

[Doctorbass]

yes i still can se it, i only loose few Ah on the 13 other bank that can not be usable due to that low bank cutting the power too soon.  i dont think i will investigate to find a low cell in the bank, too much time consuming, i will just replace that bank with a better one.. i have 2 spare 2011 battery in my lab

Doc