CCA – Cold Cranking Amps – (CCA) is the maximum amperes that can be continuously removed from a battery for 30 seconds at 0°F before its voltage drops to unusable levels. A 550 CCA battery can supply 550 amperes for 30 seconds at 0°F. This rating is only useful in the selection of engine starting batteries.
CA – Cranking Amps – The discharge load in amperes which a new, fully charged battery can maintain for 30 seconds at 32 degrees farenheit at a voltage above 7.2volts.
MCA – Marine Cranking Amps – The discharge load in amperes which a new, fully charged battery can maintain for 30 seconds at 32 degrees farenheit at a voltage above 7.2volts.
HCA – Hot Cranking Amps – The discharge load in amperes which a new, fully charged battery can maintain for 30 seconds at 32 degrees farenheit at a voltage above 1.2 v/cell
RC – Reserve Capacity – Reserve capacity is the number of minutes a battery can maintain a useful voltage under a 25 ampere discharge. The higher the minute rating, the greater the battery’s ability to run lights, pumps, inverters, and electronics for a longer period before recharging is necessary. The 25 Amp. Reserve Capacity Rating is more realistic than Amp-Hour or CCA as a measurement of capacity for deep cycle service. Batteries promoted on their high Cold Cranking Ratings are easy and inexpensive to build. The market is flooded with them, however their Reserve Capacity, Cycle Life (the number of discharges and charges the battery can deliver) and Service life are poor. Reserve Capacity is difficult and costly to engineer into a battery and requires higher quality cell materials.
For instance, Rolls, Surrette and Lifeline use thicker lead grids (the plate’s skeletal structure) to support additional positive plate oxides which are compressed into a denser form in order to add battery reactive material for greater Reserve Capacity and Cycling Performance. In addition, these plates are separated by indestructible separators. These mats hold the active oxides tightly in place during the cubical plate expansion which occurs during deep discharging, instead of allowing the oxides to shed off and precipitate to the bottom of the battery. Construction materials such as those raise the Reserve Capacity of a battery and increase the battery’s Cycle Life.
AH – Ampere Hour Capacity – A is a unit of measurement for battery capacity, obtained by multiplying a current flow in amperes by the time in hours of discharge.
(Example: A battery which delivers 5 amperes for 20 hours delivers 5 amperes times 20 hours, or 100 ampere-hours.)
Manufacturers use different discharge periods to yield an different Amp-Hr. Rating for the same capacity batteries, therefore, the Amp-Hr. Rating has little significance unless qualified by the number of hours the battery is discharged. For this reason Amp-Hour Ratings are only a general method of evaluating a battery’s capacity for selection purposes.
The quality of internal components and technical construction within the battery will generate different desired characteristics without effecting its Amp-Hour Rating. For instance, there are 150 Amp-Hour batteries that will not support an electrical load overnight and if called upon to do so repetitively, will fail early in their life. Conversely, there are 150 Amp-Hour batteries that will operate an electrical load for several days before needing recharging and will do so for years. The following ratings must be examined in order to evaluate and select the proper battery for a specific application: COLD CRANKING AMPERAGE and RESERVE CAPACITY are ratings used by the industry to simplify battery selection.
Battery Cycle Life – One cycle of a battery is a discharge from full charge to full discharge and a return to full charge again. The total number of cycles a battery can perform before failure is called its Cycle Life. Most battery manufacturers will not discus the Cycle Life of their product. Many advertised Deep Cycle batteries have not been tested, or, which is the case with cranking batteries, were never designed for long Cycle Life .
Battery Definitions Useful in Choosing a Battery for Your Application