While testing a faulty device, I unexpectedly drove 5V USB into a protected NCR18650B cell for about one second. The voltage of the cell itself did not exceed 4.3V, which is inside the 4.35V safety limit, and settled to below 4.1V when power was removed, but I'm not sure if the cell is still safe to use.
Should I be worried?
Draco
Hmm... So I did some research and found that the effect of overcharging is plating of the anode (negative electrode) with lithium metal, the same that would happen if one attempted to charge Li-ion in below-freezing temperatures. After some thought, I kinda think the battery is still usable given the brevity of the event and the peak voltages reached, but I will be monitoring the battery closely during the next few charge cycles using an IR thermometer.
Is this okay, or should I replace the cell?
Should I be worried?
Draco
Hmm... So I did some research and found that the effect of overcharging is plating of the anode (negative electrode) with lithium metal, the same that would happen if one attempted to charge Li-ion in below-freezing temperatures. After some thought, I kinda think the battery is still usable given the brevity of the event and the peak voltages reached, but I will be monitoring the battery closely during the next few charge cycles using an IR thermometer.
Is this okay, or should I replace the cell?
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