The difference between 21700 and 18650 lithium batteries

18650 battery originally refers to nickel-metal hydride batteries and lithium batteries. As nickel-metal hydride batteries are relatively seldom used today, they are now mostly referred to as lithium batteries. The battery 21700 is a cylindrical battery model. In detail, it refers to: 21 means that the outer diameter of the cylindrical battery is 21mm; 700 means that the height of the cylindrical battery is 70.0mm. The most intuitive difference between 21700 and 18650 lithium batteries is the larger size. Due to the limitation of battery material performance, increasing energy density by adding new volume has become a key consideration for the company. my country clearly proposes that in 2020, the energy density of power lithium-ion battery cells will exceed 300Wh/kg, and the energy density of power lithium-ion battery systems will reach 260Wh/kg; in 2025, the energy density of power lithium-ion battery systems will reach 350Wh/kg. The energy density requirements of power lithium batteries continue to increase, which will inevitably continue to promote the reform of lithium battery models. The energy density of the 21700 battery system is about 300Wh/kg, which is about 20% higher than the 250Wh/kg of the original 18650 battery system. The increase in battery capacity means that the number of cells required for the same energy is reduced by about 1/3, which reduces the difficulty of system management and simplifies the number of accessories such as metal structures, although the weight and cost of a single cell have increased , But the weight and cost of the battery system PACK have been reduced. 21700 battery comparison 18650 batteries are all lithium batteries, but the specifications of the lithium batteries are different, the voltage is the same, but the difference is the size and battery capacity, the 21700 must be larger than the 18650 in size, and the capacity is also larger. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What are the advantages of lithium iron phosphate battery packs?