iPad 2 mini with weird battery issue
The battery is failing/dead, the circuitry inside may be damaged, or both. You need to have this iPad serviced and needs to be opened and checked out by an Apple Tech. If it is out of warranty, any reputable 3rd party Apple Tech fixit shop should be able to help.

There's nothing anybody can do remotely - the device has obvious hardware issues. I've handled enough iPad minis in similar shape to be certain of it.

Your best bet is to get a new (or newer) iPad. If funds are tight, Apple has pretty good refurbished models in the Apple Store (US link).