Sorry I'm a decade late. I had this exact same problem with a Vita I got from a friend a couple weeks ago. No life from the thing, except for when it was plugged in. Even then, the only sign of life was the orange light flashing for about a second when I held the power button down. I opened it up and saw the battery was expanded and pillowy. Bought a replacement battery from iFixit and it works fine now. Hope this helps.