So you have hardmodded your only battery?
Also you did not make a Backup of your original NAND?
That is not so good

I belive you have first used a Memorystick with a different from the original IPL.
(probably Boosters multi IPL which allows to load the PSP normal with a pandora battery inserted and would boot different menus when you press certain butons on boot time...)
Now after you have formated your memorystick the IPL on the stick got lost...
Try to format your stick with
FakeCard 1.5 and re-install your modified multi IPL.
Also you can try to fix your Battery so that you can from now on soft mod it...
Esle you probably will need to start the PSP only with the AC adapter and then pop in your crippled battery
