18650 battery
Cylindrical battery size
From Wikipedia, the free encyclopedia
An 18650 battery[1] or 1865 cell[2] is a cylindrical battery size (often lithium-ion battery or sodium ion battery) common in electronic devices. The batteries measure 18 mm (0.71 in) in diameter by 65.0 mm (2.56 in) in length, giving them the name 18650.[3] The battery comes in many nominal voltages depending on the specific chemistry used.
 Panasonic 18650 batteries from inside a laptop. Each cell has a capacity of 2450 mAh. | |
| Component type | Power source |
|---|---|
| Working principle | Electrochemical reactions, Electromotive force |
| First produced | 1994 |
| Pin names | Anode and Cathode |
| Electronic symbol | |
 | |
Sony developed the 18650 in 1991,[4][5] though Panasonic claims to have done so in 1994.[6] They are commonly used in power tools, electric bicycles, laptops, and electric vehicles.[7]
Chemistry
18650 batteries are most commonly lithium-based.[citation needed]
NMC811 can be doped with ZrO2 to produce a cathode for these batteries.[8]
By 2023, some sodium-ion variants were available in the 18 mm × 65 mm cylindrical cell form factor as well.[9][better source needed]
In 2024, a potassium-ion variant was unveiled in the 18650 format that utilizes a proprietary 4 V Potassium Prussian White cathode and a commercially available graphite anode.[10]
Packs
18650 batteries are commonly used in packs, where a battery management system (BMS) is required, especially once cells age and perform differently. BMS boards balance the voltage of cells in series and protect against over- and under-discharge.
Products using 18650 cells
18650 battery cells are used in a wide variety of products from the 1990s through the 2020s, and are widely regarded as the most produced lithium-ion cell size.[11] 18650/1865 cells are used in many laptop computer batteries, cordless power tools, many electric cars, electric scooters,[12] most e-bikes, older portable powerbanks, electronic cigarettes,[13][14] portable fans, and LED flashlights. Nominal voltage is 3.6–3.7 V.[15][7]
In the electric automobile sector, they are used in the first three vehicles manufactured by Tesla: the first-generation Roadster (late 2000s), Model S (2012+), and the Model X (2015+).[16]
See also
