回答“Why won't my iPhone charge after the battery drained completely?”This is my guess: non-oem battery does not have the correct BMS whereas the Apple BMS will not allow the OEM battery from dropping below a certain level so that the OEM battery will always turn on. For example, the iphone won't allow the Apple OEM battery with the correct BMS to drop below say 2.5V whereas the not-OEM battery without the correct BMS will drop below 2.5V to say 2.3V. At 2.3V with the non-OEM battery, the phone will never turn on. The way to increase the voltage is to open the iPhone, remove the connector from the battery to the iPhone, plug in the Lightning charging cable (with power), use a heat blow dryer for about 10 seconds to warm up the battery and reconnect the battery connector to the phone. Do the hard turn on (home + side buttons at the same time) and it will start charging.