The battery is what powers the device when it is not connected to the power cord. The camera does not function without a properly installed and charged battery. Furthermore, lithium-ion batteries like the one found in this device degrade over time. The battery is expected to need replacing after several years of use. Use this guide to replace the battery.
Locate the battery compartment on the back of the camera. It is the panel with the plastic ridges for simple removal.
Slide the battery compartment cover down off of the camera body.
Pry up the battery from the bottom using a finger and remove the batter from the case.