Battery problem- drains and get hot

[TechNewbie]

Have searched high and low to figure out why my Omnia battery drains and gets hot. Problem started 2 days ago, and noticed it was hot in standby mode. i tried to charge at home overnight and only got up to 80% after 6 hrs of charge. It was very hot while charging. I previously closed all tasks to make sure nothing was running in background. Power save mode is on and I had not changed any settings. So it looks to me like it is discharging either on its own (bad battery) or something else is running and draining it. I flashed to new ROM to free up GPS,; other than that pretty stock. I will probably go to verizon store to see what they know, but was not sure if they would check ROM and void warranty? Any battery ideas? thanks