The standard "AA" batteries have the same voltage as the "C" batteries. The only difference is the "C" have a larger storage capacity. As an example: putting a small 12 volt battery in a car: the car will start. Now put a larger 12 volt battery in the car, it will also start. If for some reason the car is harder to start (cold weather) the larger battery will turn the car over longer because it has more cranking amps. (larger capacity). All standard AAA, AA, C, and D batteries are rated at 1.5 volt. The majority of the rechargeables are 1.2 volt with the exception of Pure Energy rechargeables being 1.5 volt.