Can someone please help me with this???? I put 14,500 miles on my XM-4000li with 20 40ah cells, with absolutely no problems. Plug and ride. Simple. No BMS. No problems. 47 mile range when new. Down to around 30 miles when I finally took her apart to replace the cells under warranty.
I am on my 3rd try at replacing the cells, after finding you cannot mix brand new cells with 14k mile cells. I now have all brand new 40ah cells, but some are thundersky (yellow) and some are winston (black). I wired them up in parallel for 3 days to completely balance them, and all cells were at 3.30 when I put them back in the cycle.
After charging for an hour, 2 of the thunderskys were at 4.25 volts !!!!! And the 8 winstons had barely budged, at 3.31 volts.
Does BMS actually regulate the charge to each cell?? Or does it simply shut down the charge if any cell goes over 3.8 (or a preset limit) and shut down the cycle if a cell goes under 2.5 (or a preset limit) ???
I cannot undestand why my original cells remained so perfectly balanced through 550 charges.