How much power do you use to recharge high powered Nickel Metal Hydride (NiMH) batteries?
Charging a set of four 2500mAh batteries with a Maha PowerEx 401FS charger (on soft charge at 300mA charge rate) should take about 9 hours. 300mA at 12V is 3.6 watts of power. To charge for 9 hours at 3.6 watts, that’s 32.4 watthours. At a price of fifteen cents per kilowatt hour, the cost is 32.4/1000 x 15 cents, or 0.48 cents to charge the batteries. Even if the efficiency of the chager was only 50%, the cost would be 0.96 cents to charge the four batteries. So if you recharge your batteies once every week, the cost is 0.96 cents x 52 weeks, or 50 cents for the whole year. That’s low cost battery power!
