Temporarily test operation by inputting power of 18650 Li-Ion battery.

I connected this phone with an 18650 battery Games and car navigation, cousins are trying to recycle toys for kids

The part that could be a problem. If you enter the battery power as shown in the picture, you can charge the battery through your mobile phone. However, since there is no battery charge / discharge protection circuit I think the battery should be used with a charge / discharge protection circuit.

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