Batteries are characterized by their ability to deliver the required current over some period of time, called Amp-hours. Also known as capacity, different types of batteries have different characterizations curves that show their amp-hours as a function of time.
Verifying the manufacturer's capacity after the battery has been used for some time is known as a battery charge-discharge test.
Source measure units, devices that function both as a power supply and a multimeter/electronic load, are ideal for these types of tests. In this video, applications engineer Barry Bolling uses a GS610 source measure unit to perform a charge-discharge test on a lead acid battery to show how to test lead acid battery capacity.