Welcome to iMore! Are you concerned that your iPad is draining battery too fast or that it's slow, or both?
For battery issues,
this article should help. Although it was written for the iPhone much of it applies to your iPad.
For battery drain and lag issues the best thing you can do for yourself is restore your iPad and set it up as a new device. You'll have to download your apps and set everything back up but it will more than likely help with both of your concerns.
Let us know if you have any more questions. We are happy to help!
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