A device to store elecrical energy. consisting of plates and an outer body, with electrolyte inside. There are two main types. starting batteries, and lesure batteries.
The first type offers a large starting current, to turn large starting motors on engines, requiring hundreds of amps. Found usualy in everyday motor vehicles.
The latter is used on remote installations and for leasure activites, where current is used over a long period of time, but at a lower level than starting. the current levels expected can be from 10ma upto 20A depending on situation.
batteries can be seriesed or connected in parralell to gain the correct voltage or current required.
I couldn't start the car, as it had a flat battery.