20s8p 84V 20Ah Battery pack
Test connection diagram
Cell 1 voltage: 3.885V , Cell 2 voltage: 4.068V , Cell 3 voltage: 4.063V
Cell 2 starts charging , Cell 1, cell 2 voltage changes simultaneously , Cell 1 and Cell 3 are also charging
The battery is at risk of overcharging or overdischarging.