I just bought a PSP 3001 off eBay to replace my broken-screen'd 2000. It came with one of the older, fat batteries. It has everything I could ask for from a 3000... easily-upgradable 5.50 firmware in particular. Except for one thing... The unit will only operate when plugged in. Neither the battery it came with nor the one from my 2000 will power it. The 2000 works and charges with either, and I even connected it to my television to ensure everything was working properly. I've tried cleaning the battery contacts with rubbing alcohol to no avail. I'm thinking I'll have to return the unit and get my money back, but I thought I'd come here first just to see if anyone else has experienced any similar issues. Thank you in advance!