AH (Amp-hours) and mAh (milliamp-hours) are units of measurement that are used to indicate the capacity of a battery. The capacity of a battery refers to the amount of electrical energy that it can store and deliver.

Amp-hours (AH) is a unit of measurement that is used to indicate the capacity of a battery in terms of the amount of current that it can deliver over a specific period of time. For example, a 12AH battery can deliver a current of 1 amp for 12 hours, or a current of 2 amps for 6 hours. The higher the amp-hour rating, the greater the capacity of the battery.

Milliamp-hours (mAh) is a unit of measurement that is used to indicate the capacity of a battery in terms of the amount of current that it can deliver over a specific period of time. The difference with mAh is that is it is a smaller unit of measurement than amp-hours, 1Ah = 1000mAh. For example, a 1200mAh battery can deliver a current of 1 amp for 1.2 hours, or a current of 0.5 amps for 2.4 hours. The higher the mAh rating, the greater the capacity of the battery.

In practice, you will most likely see mAh rating on small batteries, while Ah rating is more common on larger batteries such as car batteries or UPS batteries.

It’s important to note that the capacity of a battery can be affected by a variety of factors such as the temperature, the rate of discharge, and the age of the battery. Therefore, the actual capacity of a battery may be slightly different from its rated capacity.