Quote from the source: I recently received an official Sony PSP-110 battery (the original fat PSP battery), as new from Amazon. It seems to be a completely genuine Sony part, but it can't be successfully converted to Pandora - the battery creator shows lots of errors, even when flashing an EEPROM image from an older Sony battery.
The only difference from the older battery is that the old battery was made in China, the new battery is made in Japan.
It wouldn't be surprising for Sony to have patched their batteries so that they're Pandora-proof. If this is true, then it still shouldn't be a big problem - I'd recommend buying a new, large capacity battery to use as a regular battery, and using the original battery that came with your PSP for Pandora. And of course, you can always use Booster's multi-IPL loader to use your Pandora battery as your primary battery, if you want. Just don't go buying new Sony batteries for use with Pandora.