Regarding Pandoras battery...

[Jecht808]

Can a pandoras battery be made with a PSP slim with custom firmware to downgrade a PSP phat? if so, I use the phat PSP's battery don't i?

Is there a specific firmware that the phat psp needs to be? It's FW 3.11 and me or my friend don't have Lumines you see...

[rotoruaboy]

If you search PSP help or this section of the forum, there are a couple posts confirming phat pandora batteries work on both slim and phat, however, some updates claim new genuine sony batteries may be pandora proff

http://www.noobz.eu/joomla/news/are-new-sony-batteries-pandora-proof.html

samilar news are also on psphack and pspmod forums