Quote Originally Posted by f/16 View Post
I read online somewhere that it is easy to replace. Maybe the battery cover on mine is stuck or something. I'd hate to have to send it to Pentax just for that
My sentiments exactly. However it might be worth a call to a Pentax service centre to make sure that what seems to be the way to do it, actually is. Risking a breakage will be even more expensive.

Somebody somewhere must have replaced the battery. You might try Pentaxforums as suggested. Most of the users seem to be "digis" but there are a few experienced users of P645s

Best of luck