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Milliamp Hour (mAh) An Milliamp Hour(mAh) is a unit for measuring electric power over time. mAh is commonly used to describe the total amount of energy a battery can store at one time. It's the easiest way to distinguish the strength or capacity of a battery. The higher the mAh, the longer the battery will last.
A current flow for one hour measured in amperes (amps). Abbreviated Ah and commonly called amp-hour, it is widely used to rate how long it takes for a battery to discharge. For smaller batteries, a milliampere-hour (mAh) rating is used.