CR (Coin Type Lithium Manganese Dioxide Battery). The coin type lithium manganese dioxide battery (CR battery) is a small, lightweight battery with an operating voltage of 3V and the ability to operate over a wide temperature range. It has a wide range of applications, both for powering devices such as wristwatches and electronic calculators and can be used in many types of electronic devices. This battery is a large coin shaped cell, commonly found in small electronic devices and watches. Maxell Batteries are utilized as the original equipment for many of the world's most popular watches. These batteries are also the power source for Motherboards, calculators, keyless entry, games, cameras and personal organizers etc.