Emulate Li-ion battery using a charger
The closest thing I've experienced was with my laptop. At some point the battery died and the laptop started misbehaving (rebooting, not starting etc.) I removed the battery and use it only on charger now and have no issues. Note that the battery was encapsulated in the laptop, so I had to disassemble it to remove the battery. Try first removing the battery from your Ipad and running it with charger only.