Today my board had shut downs while still at 43-44V (12S5P). I had to call my wife to come and get me and endure all the snarky comments on the reliability of an esk8 Anyway I opened up the battery when I got home. The series connections were fine but the last P group measured at 3.10V when all the others were at 3.70V. This explains the shutdowns as I use a discharge BMS (Bestech HCX-D223V1). I am currently charging that particular P group by itself until it reaches 3.70V as the others and will then continue through the BMS.
Now my question is how/why this happened?
When I measure the output voltage on my BMS I get approx. 1V lower with the e-switch in the off position and the actual battery voltage in the on position. Is this normal? Shouldn’t I get 0V with the e-switch in the off position?
I don’t think I have a defective cell since I would probable get shut downs in other situations since I tend to push my board really hard from time to time. My guess is that it is a faulty BMS that somehow leaks current only from the last pack. What do you guys think?