Read car battery specifications by examining the numbers on the label and deciphering them. Most car batteries have a manufacturer's name and model number along with ratings for cold cranking amperage, cranking amperage, reserve capacity and ampere hours. Some also include the date of manufacture or first use.
The manufacturer's name and model number typically appear prominently on battery labels. Under these designations, a number followed by CCA indicates cold cranking amps. This is the amount of power the battery requires to deliver 7.5 volts for cranking a car for 30 seconds at 0 degrees F. The number followed by CA indicates the amperage required for the same delivery at 32 degrees F.
Each battery also has an RC designation that provides information on the reserve capacity of the component. This measurement is in minutes, and it tells users how long the battery can power critical vehicle electrical systems when the system no longer receives a charge. This is crucial for when alternators or their delivery systems fail. Ampere hours, marked as Ah, indicate how many amps a particular battery can discharge over 20 hours before it completely loses its charge. The date information makes it easy for users to determine when to replace a battery.