Cor, I didn't want to hijack Michael's thread so I'm starting a related one. In your recent message to him you implied that with subsequent charging a series pack can actually move closer together (i.e., become more balanced). Is that really true? I'm not questioning your judgement here - I really want to know. I had assumed that the best you could hope for was that the overall balance would stay relatively stable and only drift further apart as the batteries aged.
This is quite timely for me. When I recently replaced my pack of 15 @ T-875s I was in a hurry to get my truck back on the road and had to accept the set that my supplier got for me (he gave me a good price and delivered them for free). Unfortunately the initial spread was 0.11 volts from highest to lowest when they arrived. After about 20 cycles I let them rest for 24 hours and the spread was the same. But this morning, after 48 hours of rest (and about 60 cycles of use) the spread had dropped to 0.07 volts. Most of the difference appears to be due to the batts with the highest voltages (8.59 volts) dropping by 0.05 volts to 8.54 volts. That would seem to be more than just measurement error, so it seems to confirm your implication that the pack could in principle become more balanced. I certainly welcome the possibility. Your thoughts? Comments from others also welcome of course. Peter Flipsen Jr http://www.evalbum.com/3739 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140203/aa762ee8/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
