What does mah mean on a battery?
mAH means mili ampere hour. It is a measure of the energy storage capability of the battery. If the battery is rated for say 1000mAH, then it is capable of delivering 1000mA for 1 hour. If the battery were rated for 2000mAH then it could deliver 2000mA for 1 hour, so it would have twice the energy capacity of the first battery. If you know what your load takes – for example 100mA, then a 1000mAH battery could sustain this load for 10 hours (1000/100). If the load were 2000mA then the battery could only support the load for half an hour (1000/2000). The ratings are worked out to a discharge voltage of about 9 volts for lead acid – ie the terminal voltage has reached 9v after ‘taking away’ its rated capacity. Bigger capacity means able to run a given load for a greater length of time.
