Well put Neil, I needed that. Thank you.
Todd-
> There is little relationship between CCA and amp-hours (A-H).
> Cold Cranking Amps is influenced by a battery's internal resistance.
> The lower the internal resistance, the higher the current it can
> deliver to a load. Battery construction and battery type influence
> internal resistance. More lead & short, heavy cell connections make
> a lead-acid battery's internal resistance lower.
> Even relatively small Ni-Cad batteries with vented-cell construction
> typically have extremely high peak current capability due to their
> very low internal resistance. Their amp-hour rating isn't high but
> they can deliver a great burst of current for a short time. For
> example, Ni-Cad missile batteries had a rating of only 4 Amp-Hours
> but they could put out 18 amps for 6 minutes. Their short-circuit
> current could fry a small screwdriver.
> Amp-Hour ratings are based on the time it takes to discharge a
> battery (to a certain voltage) with a lighter load. Batteries
> optimized for A-H performance are like a deep-discharge battery
> while batteries optimized for CCA are the types that are used for
> starter motors. Some types are a compromise between the two.
> The battery manufacturer should be able to furnish both CCA & A-H ratings
> for their batteries.
> Regards, Neil Tucson, AZ
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