PSP custom firmware - switching mem sticks

[Niode]

You really shouldn't use that battery in the PSP under normal use. The jig kick battery looks for specific files on the memory card to use at boot up, that's how Sony fixes bricked PSPs, it simply tells the PSP to boot the firmware from the memory stick rather than the onboard flash since it has been corrupted/deleted. I'd suggest updating to the latest 5.00 M33 custom firmware using your current jig kick boot method, since you can't boot otherwise (due to the reasons I outlined earlier). This will flash your onboard nand0 with the firmware, and once complete will allow the PSP to be booted without a battery and memory stick (obviously you need the power adaptor in it). Once you get to a state where the PSP boots without needing a memory stick/jig kick battery combination, then you can just buy a new battery and a new memory card and you will no longer have any problems.

[dedalusdedalus]

You really shouldn't use that battery in the PSP under normal use. The jig kick battery looks for specific files on the memory card to use at boot up, that's how Sony fixes bricked PSPs, it simply tells the PSP to boot the firmware from the memory stick rather than the onboard flash since it has been corrupted/deleted. I'd suggest updating to the latest 5.00 M33 custom firmware using your current jig kick boot method, since you can't boot otherwise (due to the reasons I outlined earlier). This will flash your onboard nand0 with the firmware, and once complete will allow the PSP to be booted without a battery and memory stick (obviously you need the power adaptor in it). Once you get to a state where the PSP boots without needing a memory stick/jig kick battery combination, then you can just buy a new battery and a new memory card and you will no longer have any problems.

Ahhh, that explains it.

The jig-kick battery is also likely to be the reason why I've been experiencing corrupt save files. I've never experienced a corrupt save file prior to using the jig-kick.