Comparing battery performance requires an understanding of a few bits of jargon such as:

Cold Cranking Amps (CCA). The amperage a battery generates at 0°F. Don’t confuse CCA with CA (Cranking Amps) which is 25-50% higher than CCA.

Reserve. The number of minutes a battery can produce at least 25 amps and 10.5 volts at 80°F. In other words, if your alternator fails, reserve is how long you can keep driving on battery power alone. Stock batteries average 85-100 reserve minutes. N70Z (battery) is about 130.

Deep Cycle. Normally used to power engine-off accessories, fridges, etc. Deep cycle batteries are designed with thick internal plates that allow extended-reserve capacities, and many discharge-recharge cycles. But they aren’t starting batteries. They are not suited for the starting cranking-type high amp draw involved in winching etc. Such use may shorten the life of a deep cycle battery.

Amp hours. A rating only for deep cycle batteries, not usually applied for starting batteries. An 85 amp hour rating means the battery will last 85 hours with a 1 amp draw, 8.5 hours with a 10 amp draw, etc.

Hopefully at the next meeting Jeff Rees from Apex Batteries will come and show us some of the latest batteries from the U.S.

Trevor

NB: The information provided above is included in good faith - should you have additional information or wish to provide an opposing view I would welcome your comment (or please write to the Editor)