Instructions
Turn off the PSP and unplug the power adapter.
Turn the PSP over and slide off the battery cover. The battery cover is located on the right side of the device and is marked with a small battery icon.
Pull the battery out of the PSP and examine it for any obvious external damage. If the battery is cracked or dented, it may not work properly and can even be a hazard. Replace a damaged battery as soon as possible. If the battery is not damaged, proceed to the next step.
Carefully align the metal contacts on the battery with the metal contacts on the PSP, then firmly insert the battery. If a battery is not properly seated, or placed, in the PSP, the PSP will turn off when you try switching from external to internal power.
Plug the power adapter back in and turn on the PSP. A charging icon should appear, along with the current battery power level.
Unplug the power adapter once the battery is above 30 percent power. If the PSP switches to internal power, the battery is functioning correctly. If the PSP does not switch to internal power, there are two possibilities. The PSP itself may require servicing, or the battery is not working correctly. If possible, test the PSP with another battery to determine whether you need to purchase a new battery. Otherwise, take the PSP and battery to an authorized Sony repair center.