The battery cover is screwed into place, and should only be removed when the battery has expired and needs to be replaced (usually after around 500 charges). Removing the cover with a the use of a Phillips-head screwdriver and replacing the battery will reset all the unit's settings, including as the user's name and birthday, and this information must be re-entered again. However, it will not affect saved data on Nintendo DS Game Cards or Game Boy Advance Game Paks.

If players have to pause the game they're playing for any length of time, they can sustain battery life by simply closing the Nintendo DS. This will put the system into Sleep mode, pausing the game and powering down the battery. A console in Sleep mode can run for several hundred hours without completely draining the battery. However, the Sleep mode function only works with Nintendo DS games (not Game Boy Advance games), and certain DS games (such as Animal Crossing Wild World) will not pause when the console is shut, although the backlight, screens and speakers will turn off.