If my memory on electrical engineering still intact, the reason why the GP gets hot might be due to the GP batteries are having lower internal impedance then the Sanyo/Oly batteries. In this case the GP will draw much higher current then the others and hence generating more heat.Originally posted by Kevin
Blitz, according to Leslie from John3:16, The charger can charge any NiMH re-chargeble battery but if you use GP, it get very hot (won't explode lah). If you use Sanyo then not so hot. He doesn't know why, just empirical statistic!