My PSP has hit the "battery no longer works" wall and so now if I want to play it I have to keep it plugged in... you should port Jenka's Nightmare if it hasn't already been done.
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SuperJaws100
andwhyisit
I heard that if you empty it completely (more so than the psp will allow) using an led (and I mean one of those old school leds they use for battery indicators) and then charge it for 48 hours straight (without taking it off charge during that period) and it should come good. I have no experience with this of course since my battery is fine, I'm just parroting what I've heard.