Automotive Battery Cold-Cranking Amp Temperature Adjuster By Bowling

The definition of the Cold-Cranking Amperage (CCA) of an automotive battery is the amount of current a given battery can deliver for 30 seconds at zero (0) degrees F without dropping below a specified cutoff voltage (manufacturer-specific, but usually 10.5 volts). The value of CCA will change with battery temperature, CCA increasing with higher temperatures. The following derates a given battery CCA to ambient temperature. Inputs are CCA in amps, the CCA rating temperature (usually 0 degrees F), and the battery temperature in degrees F.

Program Inputs:

Battery Cold-Cranking Amps:

CCA Rated Temperature (°F):

Current Battery Temperature:

Press this button to submit a computation: .

To reset the form input: .

Algorithm:

The CCA calculation is based on the following (from GM studies): 
k1 = 0.61 + 0.0082*temp - 0.0000417*temp2
k2 = 0.61 + 0.0082*ccatemp - 0.0000417*ccatemp2
newcca = k1 * (cca/k2)
Bruce Bowling
bbowling@earthlink.net
Bowling Superior