If the charger is putting out continuous voltage -- enough for him to reach 95 percent -- it's very likely not the charger that's at-fault. Backing it up, wiping it, and putting on Bharti or simply restoring the original OS would be something he can do to troubleshoot prior to getting any additional equipment. At that point, he would know if he has a hardware problem, or if it's a software issue. This isn't even a difficult procedure? If he were to get stuck in the process, he could just come here and have someone direct him.
I have personally had battery issues from OS changes and the like. As the power output of the charger is so small, it seems very illogical to me to assume that it could be overheating. Have you tried charging it in your car? Hooking your phone up to your computer via USB also charges the device, as it slaves power from the bus. Have you tried this, too? Any one of these methods, if it remains at 95 percent, would alleviate blame from your wall charger. At that point, it can only be your OS or the battery itself. As you have physical possession of the device and a PC, seems you could narrow it down to one issue within the night.
8700g. PIN: 23D5CBEB