top of page


Automotive acronyms and abbreviations tell a story, and they can play an important role in helping you understand your car’s battery. These abbreviations may help provide you with the information required to identify and address a wide range of common battery-related problems, from low electrolyte levels to diminished starting power.

The battery-related automotive acronyms and abbreviations discussed below will help give you the insight needed to comprehend the inner workings of one of your car’s most crucial components.

A or Amp

A and amp are terms used to describe the ampere. The ampere is the unit used to measure the current that flows through your car battery’s circuits.


AGM stands for absorbent glass mat. This is a separator material that’s made of glass microfibers, and it prevents electrolytes from spilling in the battery cell. Car batteries that use this material are called AGM batteries, and they can last up to twice as long as traditional lead batteries.

Amp-Hrs or AH

These abbreviations stand for ampere-hour, a unit that measures a battery’s storage capacity. This measurement is derived by multiplying the battery’s current (in amperes) by the time (in hours) of its discharge. For example, a battery that delivers 4 amperes for 10 hours provides 40 amp-hrs of capacity (4 amperes x 10 hours).

BCI Group Number

This refers to an identifier given by the Battery Council International (BCI). It contains information that can help identify traits such as a battery’s dimensions, voltage and polarity.


CCA stands for cold cranking amperes. The battery industry uses this term to help define how well a battery is able to start a car’s engine in frigid weather. The greater the battery’s cold-weather starting power, the higher its CCA rating. Note that a battery’s starting power fades as it’s used over the years. An older battery that’s been in use for a while may not be able to match the CCA rating it had when it was new.


RCM stands for reserve capacity minutes. This is a measurement that identifies a battery’s ability to sustain an electrical load. It’s defined as the length of time (in minutes) that a lead-acid battery can deliver 25 amperes in 80-degree weather before having its voltage drop below 10.5 volts.

SLI Battery

SLI stands for starter, lighting and ignition, and this term refers to the aspects of a car’s performance that rely on battery power. An SLI battery is a rechargeable lead-acid battery used to power a car.

Sp. Gr. or SG

These abbreviations stand for specific gravity, a measure used to identify a battery’s electrolyte concentration. With this measurement, the battery’s electrolyte density is compared to that of water.


VRLA is a term used to describe a valve-regulated lead-acid battery. These batteries are maintenance-free and leak-proof, and they have a safety vent to release gas if there’s a buildup of internal pressure. An AGM battery is a type of VRLA battery.

Watt-Hrs or WH

These abbreviations stand for watt-hours, a measurement used to identify a battery’s electrical power.

From AGM to VRLA, the terms discussed above can give you valuable information regarding your car’s battery. With this knowledge, you can get the most out of your battery and will have a better understanding of any issues that may arise.

Check out all the car battery products available on NAPA Online or trust one of our 16,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on understanding your car’s battery, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

Featured Posts
Recent Posts
Search By Tags
bottom of page