Why is the "18650" or "2170" battery? In fact, the 18650 battery is the first by the Japanese SONY company set a standard battery model, the number actually represents the battery size specifications, where "18" refers to the diameter of 18mm, "65" refers to the height of 65mm, "0 "Means a cylindrical battery. Then the "2170 battery" What does it mean? In notebooks, cameras, toys and lighting equipment and other products, 18650 battery is already very mature and stable lithium-ion battery specifications, battery manufacturers in the specifications of the battery technology has many years of accumulated experience, the battery consistency and Security has a very high level. At present, many notebook computers using the figure on the 6 core (that is, 6) lithium batteries, cash Tesla MODEL S and MODEL X also uses the same specifications 18650 battery, the lithium battery cell size is relatively small, so To 85kWh battery pack, for example, the entire battery pack is composed of more than 7000 lithium battery cells. Because those who wear a white coat of chemical Ph.D. is still difficult to revolutionize the battery technology, so the energy density of lithium batteries can not be greatly improved. For electric-powered cars, this is a technical limitation. Fortunately, manufacturers have another way to go - to reduce battery manufacturing costs, which is turned Tesla 2170 battery one of the important reasons.