Introduction to the protection device of Rechargeable Square Pouch Battery
Currently, there are generally three mainstream lithium battery packaging forms, namely Rechargeable Cylindrical Pouch Battery, Rechargeable Square Pouch Battery and soft pack battery. Rechargeable Square Pouch Battery generally refers to aluminum shell or steel shell Rechargeable Square Pouch Battery. At present, the popularity of Rechargeable Square Pouch Battery is relatively high, because the structure of Rechargeable Square Pouch Battery is relatively simple, unlike Rechargeable Cylindrical Pouch Battery, which uses high-strength stainless steel As accessories such as housings and explosion-proof safety valves, the overall accessories are lighter in weight and relatively high in energy density, so the production is relatively simple and the cost is relatively low.
So what are the safety protection structures of Rechargeable Square Pouch Battery?
The main safety structure of a typical Rechargeable Square Pouch Battery is NSD acupuncture safety device, OSD overcharge protection device is two very important devices, which can ensure that the battery will not be overheated due to overcharge during use.
Acupuncture safety protection device is actually a metal layer, such as copper foil, is added to the outermost surface of the core. When acupuncture occurs, the local large current generated at the acupuncture position can quickly pass through the large area of the copper foil. The current is reduced, which can prevent local overheating of the acupuncture position and slow down the occurrence of thermal runaway of the lithium battery.
Overcharge safety protection device, the current safety design can be seen on many batteries. Generally it is a metal sheet, used with the fuse, the fuse can be designed to the positive current collector, the pressure generated inside the lithium battery during overcharge causes the OSD to trigger an internal short circuit, which generates an instantaneous large current, which causes the fuse to fuse, thereby cutting off the internal current loop of the battery . At present, the shells of Rechargeable Square Pouch Battery are generally steel shells or aluminum shells. With the market's pursuit of energy density and the progress of production technology, aluminum shells have gradually become the mainstream.