The C battery (C size battery or R14 battery) is a standard size of dry cell battery typically used in medium-drain applications such as toys, flashlights, and musical instruments.
As of 2007, C batteries accounted for 4% of alkaline primary battery sales in the United States. In Switzerland as of 2008, C batteries totalled 5.4% of primary battery sales and 3.4% of secondary (rechargeable) battery sales.
A C battery measures 50 mm (1.97 in) length and 26.2 mm (1.03 in) diameter.
The voltage and capacity of a C-size battery depends on the battery chemistry and discharge conditions. The nominal voltage is 1.5V. Alkaline C batteries have a storage capacity up to 8000 mAh while rechargeable NiMH C batteries can hold up to 6000 mAh. Zinc-carbon C batteries usually hold up to 3800 mAh. Compared to the AAA and AA batteries, C-batteries’ storage capacities are significantly higher.
Like the D battery, the C battery size has been standardized since the 1920s. The AA, AAA, and N sizes have been in common use since the 1950s.
The C battery is called “14” in current ANSI standards of battery nomenclature, and in IEC standards is designated “R14”.