I own a Galaxy Y, which I haven't used since an year, because of a problem that had developed then, until now when I wanted to use it again.
The problem is the following, with some information about the phone itself.
I had rooted the phone earlier, and put in a custom ROM called Jelly Blast v2.0. Later one day, the phone's battery died overnight, and then it discharged really fast, like 3% in 1 minute. So I flashed the stock ROM with Odin, and unrooted the phone. The problem persisted. Whenever I charged the phone, it became hot like hell, and charged 1% in 10 minutes or so. Then I stopped using it, until now. I checked the battery with a multimeter, and it showed 0.00v, that is fully discharged. So I grabbed a cut-off USB cable, plugged it into my PC, and charged the battery up to 3.66v ghetto style. I made sure the battery did not even warm up, for caution, while doing this.
Plugging it into my phone, it showed 1% charge. It charges really slow, and discharges extremely fast. I know the problem is not with the battery, since I had it changed and it showed the same symptoms.
I don't know what's going wrong, but I don't think it is the hardware. The problem should be in the software. Earlier, i had resetted it in CWM, and removed cache. Also, I had removed the battery stats. I don't know if that is the problem. Currently it is running Hyperion v9 Final ROM, with stock kernel I think.
So what should I do? Please help.