iPhone 6S won't Charge Dead Batteries

So i had a customer with an iPhone 6s and she dropped it and completely shattered the screen and lcd. the Touch ID home button also was cracked and both cameras stopped working after the fall. The phone had no life in it before the repair. After replacing the screen, Battery, Both cameras home button the top of the motherboard got really hot and as soon as the battery would die the battery would not charge. the battery charges when its above 1% but as soon as it dies it dies forever. so i changed out the battery many times and this keeps happening. I know its the motherboard but is there anyways on fixing it ?