1, overcharge protection 2, overdischarge protection 3, overcurrent, short circuit protection
Solutions after mobile phone battery protection (from network) :
1, with the original direct charging on the phone, the battery protection board will automatically open the protection circuit.
2. Short-circuit the positive and negative poles of the battery and see sparks on the electrode. Try several times and then use direct charging.
3, find a 5V direct current, with positive and negative light touch the positive and negative terminals of the battery, try several times, and then use the original charger to charge.