18650 lithium batteries
Lithium Ion Battery (Li-ion, Lithium Ion Battery): Lithium-ion batteries are widely used because of their light weight, large capacity, and no memory effect. Many digital devices use lithium-ion batteries as power supplies, despite their price. Relatively expensive. Lithium-ion batteries have a high energy density, and their capacity is 1.5 to 2 times that of nickel-hydrogen batteries of the same weight, and has a very low self-discharge rate. In addition, the lithium-ion battery has almost no "memory effect" and does not contain toxic substances, which is also an important reason for its wide application. In addition, please note that the outside of the lithium battery is generally marked with English 4.2V lithiumion battery (lithium battery) or 4.2V lithium secondary battery (lithium secondary battery), 4.2V lithiumion rechargeable battery (charged lithium battery), so users must buy the battery must Look at the signs on the exterior of the battery block to prevent the cadmium nickel and nickel hydride batteries from being mistaken for lithium batteries because they do not see the battery type.
18650 is the originator of lithium-ion battery--a standard lithium-ion battery model that Japan SONY Company set in order to save cost. Among them, 18 means diameter is 18mm, 65 means length is 65mm, 0 means cylindrical battery.
The common 18650 battery is divided into a lithium ion battery and a lithium iron phosphate battery. The lithium-ion battery voltage is 3.7V, the charge cut-off voltage is 4.2v, the lithium iron phosphate battery has a nominal voltage of 3.2V, the charge cut-off voltage is 3.6v, the capacity is usually 1200mAh-3350mAh, and the common capacity is 2200mAh-2600mAh.