hardmodding battery

I heard that the new battery models are pitched so they cant be turned to pandora... but is it possible to hardmod these pitched batteries, such as a slim battery

Nope, not that I know of. You can't find a good battery in a store now, unless maybe at gamestop or something.

Or getting a used PSP. But that'll cost some $130 from you just to buy a used PSP that is a 98% chance that it's a 2.60 or lower. Also with a battery that can be hardmodded.