Don’t put your battery(s) in the camera until you are ready to use it. Especially rechargeables in DSLRs. Small internal workings will drain down the battery and over time, if not removed, the charge will be completely used up. If I’m shooting daily I leave them in but if a camera will be sitting for a few days or a week or, since I have a number of them, won’t be in use, the batteries come out.