Greetings and thanks for posting sabrina47.
That's no good that the battery is draining so fast. Have you first tried the steps in the Battery life: Samsung Galaxy Tab S2 (T817T) doc? It's got some great ways to help save some of that battery life. If you're still wanting another battery, you'll need to contact Samsung at 888-987-4357. Samsung would be your best bet with getting another battery.
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