18650
18650 battery
Cylindrical lithium-ion battery
An 18650 battery[1] or 1865 cell[2] is a cylindrical lithium-ion battery common in electronic devices. The batteries measure 18 mm (0.71 in) in diameter by 65 mm (2.56 in) in length, giving them the name 18650.[3] The battery is 3.7 volts.
Panasonic first developed the 18650 battery in 1994 "when there was a growing need for ever smaller and lighter storage batteries that could be used for ever longer periods of time".[4] They are now commonly used in power tools, electric bicycles, laptops, and electric vehicles.[5]