Unfortunetly I cannot think of anything else.
The only thing I can think if is to buy the same battery as you had before, charge it for about 2 hours and unplug it regardless what color the light it. If the battery runs well and can get out more than a few mags worth of BBs then its possible the charger could be damaged or its possible the cells were bad from the start in both original batteries.
Perhaps you can hit up the shop you purchased from for some guidance.
"Its only a little bit on fire"