Jordan325ic
100 W
- Joined
- Aug 5, 2020
- Messages
- 121
So I was contacted by a fellow EV guy who has a strange scooter from the early 2010s which has stopped working. The scooter was created by a defunct company called "KLD". The story I was told was: during it's short life the company rewarded the first 100 investors of $100k or more with electric scooters used to demonstrate the company's technology. The scooter I have is labeled "93 of 100". The scooters were standard Vmoto brand scooters with a KLD proprietary drivetrain. ( The hub motor itself is totally bizarre with bundles of wires going to 'modular' stator blocks and a giant cast heat sink on the side, check minute 5 of the only video on youtube: https://www.youtube.com/watch?v=j2IBnKouLDg ).
Anyway, it's got a SEVCON controller, deltaQ charger and a gorgeous battery box design, obviously no expense was spared in these 'demo' builds, and it would be cool to get it running again. The charging indicator will still light up but I was told the "service indicator" came up on the gauge cluster at one point and since then the rest of the scooter is dead. So 10 year old scooter I pulled the battery and the interior design is unusual. Inside it seems there are six independent 48V modules with 6 BMSs, which join up in parallel to give 3.1kwh according to the label (48V 64.8Ah). Cells are Samsung SDI 20R, 2000mAH
So I started poking around with the multimeter and went through each group of modules to figure out how the sense wires were arranged. Once I figured out the pinout I was able to make a spreadsheet with all the voltages for all the modules.
Though the individual cell groups vary greatly within the modules I suspect it was the dead cell group 5 in Module 1 that actually caused the pack to 'fault out'.
I'm not sure where they get the 64.8Ah number but I assume each module is 13s5p or 13s6p so we're talking 400-500 new 18650s. Obviously the 'right' thing to do would be to rebuild with entirely new cells, but since we've got each module protected with its own BMS... maybe I can just rebuild the bad module. I doubt the owner is going to want to spend the money to rebuild the entire battery.
Anyway, it's got a SEVCON controller, deltaQ charger and a gorgeous battery box design, obviously no expense was spared in these 'demo' builds, and it would be cool to get it running again. The charging indicator will still light up but I was told the "service indicator" came up on the gauge cluster at one point and since then the rest of the scooter is dead. So 10 year old scooter I pulled the battery and the interior design is unusual. Inside it seems there are six independent 48V modules with 6 BMSs, which join up in parallel to give 3.1kwh according to the label (48V 64.8Ah). Cells are Samsung SDI 20R, 2000mAH
So I started poking around with the multimeter and went through each group of modules to figure out how the sense wires were arranged. Once I figured out the pinout I was able to make a spreadsheet with all the voltages for all the modules.
Though the individual cell groups vary greatly within the modules I suspect it was the dead cell group 5 in Module 1 that actually caused the pack to 'fault out'.
I'm not sure where they get the 64.8Ah number but I assume each module is 13s5p or 13s6p so we're talking 400-500 new 18650s. Obviously the 'right' thing to do would be to rebuild with entirely new cells, but since we've got each module protected with its own BMS... maybe I can just rebuild the bad module. I doubt the owner is going to want to spend the money to rebuild the entire battery.