This Energizer Universal battery charger only takes between 3 and 5 hours to charge most rechargeable batteries, making this charger quick and convenient. Only rechargeable 9V batteries take longer, charging in around 12 hours. Despite its compact appearance, this Energizer Universal battery charger is able to charge 2 or 4 x AA, 2 or 4 x AAA, 2 or 4 x C, 2 or 4 x D or 2 x 9V rechargeable batteries making it a necessity for any battery user. Approximate charging times:- AA 1300mAh 2 Hours AA 1700mAh 3 Hours AA 2000mAh 4 Hours AA 2450mAh 4.5 Hours AAA 700mAh 2 Hours AAA 850mAh 3 Hours AAA 1000mAh 3.5 Hours C 2500mAh 4.5 Hours D 2500mAh 4.5 Hours 9V 175mAh 12.5 Hours.