what voltage is car battery
Car Batteries Are Not 12 Volts. There are at least three variations of the lead-acid battery in current automotive use (1). In the most common configuration, the car battery has six cells, each producing about 2.1 volts. Thus the total battery output voltage is about 12.6 volts. It is the about in the previous two sentences that leads to trouble when a charging system is not matched to the type of battery installed.