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Discussion Starter · #1 ·
So I finally had time to analyze my suspect pack, and there was one
completely dead cell (0 volts after charging all the rest of the pack (79
cells) to 3.8 volts. I replaced the 10 pack and have first balanced the 80
pack and am now trickle charging / balancing the system.
I suspect that this was bringing down the whole system. I measured the
resistance of the cell at .4 ohms for what it is worth (the charged cells
read 0 ohms). I don't know for sure what that means net net. Clearly I'm
much better off than before, but for drag racing purposes was that bringing
me down over not being plugged in. I see that there are 3 possibilities
1. The bad cell limited to output of the pack it was in , but still
contributed to the performance of the car. Net +1-8%
2. The bad cell negated the pack it was in but didn't have any net effect
on the system. Net +8%
3. The bad cell was causing a cross charging, system draining effect. Net

I'm glad that I have one balancer per cell so that I was able to quickly
find it. (One on my parallel strings came started balancing earlier than
the rest, all but one cell, and wouldn't come up in trickle charging).


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