I too changed my battery
=== Update (11/06/2020) ===
I have now tried 3 OEM batteries including reinstalling the existing one and all cause the iPad to go into a restart loop I think iOS v14 devices are firmware locked as all show 100mAh on Coconut Plus which probably causes the restart loops. Even completed hard reset and total factory reset to see if it was something else causing it however still stuck in restart loop even when charging. I have accepted defeat and paid £106 to Apple
I have now tried 3 OEM batteries including reinstalling the existing one and all cause the iPad to go into a restart loop I think iOS v14 devices are firmware locked as all show 100mAh on Coconut Plus which probably causes the restart loops. Even completed hard reset and total factory reset to see if it was something else causing it however still stuck in restart loop even when charging. I have accepted defeat and paid £106 to Apple