Weird Battery Problem - Help

[Android Central Question]

(I'm using a ****ty phone called Gionee P5 Mini)
So i was charging my phone and it charges REALLY SLOWLY It was at 30% and I thought if I restarted my phone it would charge a little faster, So I restarted it and then it turned off and I waited for it to open up again but it didn't so I tried long pressing the the power on button and it still didn't open so I pulled the battery out and put it back in the phone again and opened it again and if you remember I restarted my phone when it was only 30% but when I opened the phone it was 91%! (Someone tell me if the battery or the phone is ****ed up or both)

 

[Tim1954]

I would start by taking the battery out and cleaning the contacts on the battery and device. After a time with the minuscule currents flowing across the contacts, a thin film can form that can hinder flow (of electrons).
Also, check for movement or loosenes when the battery is in, it should be pushed firmly up against the contacts. In some earlier Samsung devices, I used to put a bit of packing under the bottom of the battery to push it up. A good way to tell if this is a problem is to give the device a firm bump and if it turns itself off, you have your culprit.