1 Connect the power supply and leave it for a day or so (you can turn it on or not) to see if it can activate itself.

2 Take out the battery, there is a button and several LED lights on the back of the battery, press the button once or long for three seconds to see if it can be activated.

3 Generally, it is the low-voltage protection of the protection board, and it is activated. Otherwise, the positive and negative poles of the battery can be activated by tapping the positive and negative poles of the mobile power supply for a few times. After activation, there is a voltage and it can be charged normally.

4 If you understand the circuit, you can find an external power supply with a voltage between 11V and 12.6V to charge, and the current can be below 1000mA.