A starting battery is a special type of battery designed to provide a short burst of high current needed to start an internal combustion engine in cars, motorcycles, boats, and other vehicles. Important parameters for a battery include capacity (Ah), which indicates how much energy the battery stores, but it is less important for starting than the cranking amps. CCA (Cold Cranking Amps) is a number that represents the maximum current the battery can provide when starting the engine in cold conditions (usually at -18°C). The standard voltage in passenger cars is 12 V.