Hi, I'm soon going to be a new owner of a XM-3500 =). I've been doing a whole lot of reading, trying to absorb as much as I can before the scooter arrives, and I read BMS is the way to go for prolonging the batteris. I see a lot of people on the forums with a BMS in their scooters, but where did they get it, what brand, and what cost? I'm okay with a solder, but reading a schematic is beyond my skill set, so do you have any recommendations for a BMS?
This is the only one I found, but I'm not sure if it would work with the 3500 having only 20 cells?