An average car battery produces 400 to 500 cold crank amperes to start the car. Cold crank amperes are a unit of measurement that show the amount of amperes a battery can discharge in 30 seconds at 0 degrees Fahrenheit and maintain 1.2 volts per cell. Ampere-hours measure battery capacity.
Another standard way to assess how much power a battery needs to start a car is measured in volts. A battery must produce at least 12.4 volts of energy to start a car. Batteries are measured in cold-crank amperes because it is much more difficult to start a car in below-zero temperatures.