Specifications: Diameter 18mm, height 65mm, voltage 3.6-3.7V, capacity 2000-3600mAh. This is one of the most mature lithium battery models, with an energy density of up to 170 Wh/kg. Widely used in consumer electronics and power equipment such as laptops, power tools, flashlights, and electric bicycles.

2）21700 Battery

Specifications: Diameter 21mm, height 70mm, capacity 4000-5000mAh. Compared to the 18650, the 21700 offers approximately 20% higher volumetric energy density, making it the preferred choice for high-power applications like the Tesla Model 3, power tools, and solar street lights. Its advantages include higher cell capacity and fewer cells required, simplifying the BMS.

3）26650 Battery

Specifications: Diameter 26mm, height 65mm, capacity 4000-6000mAh. This model offers larger capacity and strong continuous discharge capability, suitable for high-power scenarios like power tools, energy storage systems, and industrial equipment. The 26650 is gradually replacing the 18650 in the power battery sector, becoming mainstream for high-capacity applications.

4）4680 Battery

Specifications: Diameter 46mm, height 80mm, cell capacity up to 25,000mAh. Introduced by Tesla in 2020 as a new generation of large cylindrical cells, it features tabless technology for higher energy density and faster charging. The 4680 is primarily used in Tesla's next-generation vehicles and large-scale energy storage systems, representing the future direction of lithium battery development.