yeah what the other fellows said, volts is whats usually tested here, CCA on the battery means of course, cold cranking amps and it is a spec that the manufacturer of the car says is the minimum the battery needs to be able to output when you buy it. But if you are testing it the rule of thumb is for volts.
Desired voltage, engine idling (give it two minutes to recharge from the start): 13.9 - 15.0 volts
Battery, engine off: desired, 12.8 - 13.0
marginal: 12.4 - 12.7