Junkyard e-bike part 8.2: Charging
I used a bluetooth scanner to confirm that the battery management system was online. Yay!
I connected a charger and observed its current display. Nothing. Not charging.
Hmmmn, let's get an app.
App thinks the battery is flat. Probably needs to be configured for number of cells. No obvious way to do that.
Try a different App "Xaio Xian Electrical" (name of manufacturer). Not as pretty, but it has a setting for cell count (10 cell-banks). Yay, now it says 100% full.
Connect charger and it says "temperature error". Hmmmn, this BMS has an internal temperature sensor and a socket for a second external one. Didn't come with one though. Fortunately, I buy one of everything from China so that you don't have to, and I have a packet of 10kΩ thermistors to hand.
After fitting the "optional" second temperature sensor, the battery now says "charging" when I connect the charger, and it pulls 8 amps (for about 30 seconds beforer reporting full and dropping to zero amps).
I connected a "dummy load" and the app reported that the battery was now discharging.
YAY, everything works!