There are two main types of lithium-ion battery shells: steel shells and aluminum shells:
1. Steel Shells
The first square lithium-ion batteries were mainly steel shells and were mainly used in cell phones. Batteries have been gradually replaced by aluminum shells and soft-packaged lithium-ion batteries due to the low specific energy and poor safety of steel shells.
But among cylindrical lithium batteries, there is another situation. Most manufacturers use steel as the battery shell material, because the physical stability and pressure resistance of steel materials are much higher than that of aluminum shells. Each manufacturer's design structure has been optimized, safety devices have been placed inside the battery cells. Bat safetysteel column ries has reached a new level. Currently, the cells of most laptop batteries are made of a steel shell. serves as a carrier.
2. Aluminum shell
Aluminum shell is a battery shell made of aluminum alloy. It is mainly used in square lithium-ion batteries packaged in aluminum shells. The reason is that it is lightweight and safer than steel hulls.
The aluminum shell is designed with square corners and rounded corners. The material of the aluminum shell is generally aluminum-manganese alloy. The main alloy components in it are Mn, Cu, Mg, Si, Fe, etc. These five alloys play different roles in the aluminum shell of lithium batteries. For example, Cu and Mg improve strength and hardness, Mn improves corrosion resistance, Si can improve heat treatment effectAluminum alloys containing magnesium and Fe can improve. high temperature resistance.
The material structure of the aluminum alloy shell has important safety performance considerations. These safety performances can be expressed by the thickness of the material and the bulge coefficient. The reason why lithium batteries of the same capacity are lighter than those with steel casings is that aluminum casings can be made thinner. Judging from the working mechanism of lithium-ion batteries, when charging, the lithium ions are deintercalated and the positive electrode expands; during discharge, lithium ions are integrated into the positive electrode and the negative electrode expands. the swelling coefficient can be reduced through appropriate alloy formulas.
Lithium polymer battery is a type of lithium battery, but the poLymer is packaged in aluminum plastic, which will not explode but will only swell. There are also lithium batteries with steel casing and lithium batteries with aluminum casing.
The polymer battery also depends on the material it is made from. Polymer batteries of different materials have different voltage platforms if the polymer battery is made of the same material as the original cell phone battery and has a similar value. Capacity, the protection panel is universal.
The voltage and current of a cell phone battery are so low that it is impossible to break the MOS tube.
Lithium battery protection plates of different capacities and manufacturers cannot be used universally, because the internal resistance of batteries produced by different manufacturers with different capacities is different, resulting in problems.different short circuit currents if external. parts are replaced randomly, short circuit will occur maybe the MOS tube protecting the board is burned.