Rechargeable Square Pouch Battery structure and advantages
At present, there are three main types of lithium battery packaging on the market, namely, cylindrical, square and coin cell. Among them, the structure of Rechargeable Square Pouch Battery is relatively simple, unlike Rechargeable Cylindrical Pouch Battery, which uses accessories with explosion-proof safety valves. Therefore, the overall charge of Rechargeable Square Pouch Battery is lighter and the relative energy density Also relatively high.
The main components of the structure of Rechargeable Square Pouch Battery are the following components: the top cover, the casing, the Cathod and Anode plates, the laminate or the winding of the separator, the insulation and the safety components. Among them, the two inside the red circle are safety structures, namely NSD acupuncture safety device and OSD overcharge protection device.
Acupuncture safety protection device, this is usually added a metal layer on the outermost core of the coil, such as copper foil. Then when acupuncture occurs, the local large current generated at the acupuncture position can quickly reduce the current per unit area through a large area of copper foil, which can prevent local overheating at the acupuncture position and slow down the occurrence of thermal runaway of the lithium battery.
The safety design of overcharge safety protection device can now be seen on many batteries on the market. It is generally a metal foil used with fuse, and fuse is generally designed to the Cathod electrode current collector. The pressure generated inside the lithium battery when overcharged It will cause the OSD to trigger an internal short circuit, which will generate an instantaneous large current, fuse the Fuse, and cut off the internal current loop of the battery to protect the battery from overcharging.
The shell is generally a steel shell or an aluminum shell. With the drive of the market's pursuit of energy density and the progress of the production process, the aluminum shell has gradually become the mainstream.
Compared with other types of batteries, Rechargeable Square Pouch Battery has the advantages of high packaging reliability, high system energy efficiency, relatively light weight, and high energy density; and the structure is relatively simple, and the expansion is relatively convenient. It is an important option to improve energy density; the system capacity will be relatively simple when the cell capacity is large, which makes it possible to monitor the cells one by one, and it will bring another benefit that is relatively good stability. In addition, Rechargeable Square Pouch The battery's shape can be any size, which is not comparable to Rechargeable Cylindrical Pouch Battery.