Battery Life Calculator
Generally, battery life is calculated based on the current rating in milli Ampere per Hour and it is abbreviated as mAh. Ampere is an electrical unit used to measure the current flow towards the load. The battery life or capacity can be calculated from the input current rating of the battery and the load current of the circuit. Battery life will be high when the load current is less and vice versa. The calculation to find out the capacity of battery can be mathematically derived from the following formula:
Battery Life = Battery Capacity in Milli amps per hour / Load Current in Mill amps * 0.70
*The factor of 0.7 makes allowances for external factors which can affect battery life.