Just charge the 4pcs of 2500batteries that came with the charger.
It took about 13mins to complete charging
Battery feels abit hot to my liking though this was stated in the instruction manual.
Theres a 5*5cm fan fixed to the charger to cool the batteries down.
Personally feel the fan is MORE noisy than my CPU fan
read from somewhere.....some chargers let you discharge the batteries before charging. Discharge is only necessary for NiCd batteries. NiCd batteries suffer from 'memory'. If you charge a NiCd battery when only partially discharged, the battery will remember this level and may not charge fully afterward. So it required to be reconditioned with discharge. The Ni-MH battery has no 'memory' problem...
Actually all Nickel batteries, be it Cadmium or Metal Hydride, have a condition, commonly known as the "memory effect", just that it is much less suceptible in the case of Metal Hydride as compared to Cadmium batteries. A discharge of the Nickel Metal Hydride batteries once in a month or two should give the batteries optimium performance.
I suppose the batteries get pretty hot during charging using the 15 min charger, do they? Good thing it has a fan.