A battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices.A battery’s capacity is the amount of electric charge it can deliver at the rated voltage. The more electrode material contained in the cell the greater its capacity.
source/image(PrtSc): The Engineering Mindset
How long a battery will last is determined by 2 factors, the battery capacity and the load current of the circuit. Both of these factors are explained in detail right below.All batteries come with a battery capacity rating. Watch the video from The Engineering Mindset for more info:
This is the total amount of current that a battery can supply in milliamperes during its lifetime. If a battery has a battery capacity rating of 2000mAH, it can supply 2000 milliamperes of current during its lifetime. This means it can supply 20mA for 100 hours, 200mA for 10 hours, 2A for 1 hour, since the product of all these equals 2000mA.
Capacity is measured in units such as amp-hour (A·h). The rated capacity of a battery is usually expressed as the product of 20 hours multiplied by the current that a new battery can consistently supply for 20 hours at 68 °F (20 °C), while remaining above a specified terminal voltage per cell. For example, a battery rated at 100 A·h can deliver 5 A over a 20-hour period at room temperature.//The Engineering Mindset