Charges fast and dies fast

Hey I have a iPod touch 6th gen come in for repair

anyways, this is the third one that came in wasn’t charging or turning on… so I decided to change the battery and re solder a new one in. It’ll charge very quickly and drain fast as well. I’m not sure if it’s the batteries I am getting off eBay or if something hardware is at fault on the logic board causing this issue. Is this a U2 IC Failure? Any shops that have this same problem it would be great if you could chime in with a Solution. It also recognizes with the computer and charges at 0.72 volts