ok the problem seems to be quite common and it seems to be quite common to buy a new battery to solve it but you dont have to.
1>psp only runs of ac
2>battery charging light(orange) lights only for short time then turns green again
3>battery status in xmb is
charge level 0%
remaining time -
battery status - CHARGE COMPLETE
ive checked the battery voltage through irshell it said
charge level o%
hours left 0.0
power source AC
Battery status Charging
ive googled and found out that there is the possibility to cross wire(short)the plus and minus of the battery to make it work again.
i did try it on two of my batterys more than once and it didnt work.
so i came up with another method.
the voltage of the battery was so high it was (overcharged)full
so I took a bulb of my motorbike and connected it to the battery.
it was 12V and 21W.
drained the battery (took a long time)
and even left the bulb on there for another hour to make shure that it was totally empty.
then after i put it back in the psp(without the bulb connected ;)
it finally started to catch the charge back like it used to in the old days.
i think the problem is that the chip in the battery is kinda crashed.
the chip tells the psp that its got 0%.
but the voltmeter in the psp tells the charger that its full and stops charging to prevent burning the battery.
since the chip says 0% the psp wont even try using the battery to prevent data loss.
whatever i hope i could help people with this.
it sucks having to buy a new battery when the old one is still good.
eddiedgar from germany