[. . . ] Other types of batteries may burst causing personal injury and damage. [. . . ] Insert GP NiMH batteries into GP PowerBank according to the battery polarity. Do not charge same size batteries of different capacities at the same time. Only when the charger is unplugged or the batteries are removed, the indicators will switch off. 5 16 15 * For brand new batteries, 2 to 3 times of charging and usage cycles are required to optimize the batteries' performance. [. . . ] * If batteries are stored for more than one week, always recharge them before use. [. . . ]