Peri Hart said " Most batteries don't die of old age; they are MURDERED by one form of abuse or another."
I think that says it all. My Elise EV has 94 x 50Ah Hi-Power cells which are five years old and have covered around 25,000 miles in all conditions. They are early LiFePO4 chemistry and no where near the C rating of modern CALB cells so have been punished by constant 3C discharge under acceleration and running many cells to zero volts. My BMS doesn't balance the cells so the cells fall to zero one by one if discharged too far but the car just keeps going. My decision as sometimes I was close to home after a long drive. I excuse it as R&D! Although around 15 cells have been replaced and the range is only around 50% of original before the remaining worst cells discharge, I have been more than impressed with the car as a whole. Voltage dip is quite severe in winter at -10C or lower and because my cells are not heated, I always charge immediately after driving in cold conditions so the cells are over 0C. My new build EV has 100 x 100Ah CALB and performed superbly last winter with negligible voltage dip in all temperatures. Tesla have turned cell conditioning into an art form. Correctly reasoning that an EV utterly relies on the battery pack. I have seen reports of many Roadster's having in excess of 100,000 miles on them. Motors and inverters have been around for donkeys years. Improvements can be made but it all hinges on cell capacity and life. BTW, my son is using an M1330 Dell laptop which is well over 6 years old and it still runs for hours on the original cell pack. It has always been in daily use and very often on battery only. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/Range-tp4665484p4665667.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ 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)
