Rectangular lithium battery with improved packing structure

Abstract

The invention discloses a rectangular lithium battery with an improved packing structure. One end of a rectangular shell of the rectangular lithium battery is fixed with a reinforcing plate. An electrical contact and a safety valve are fixed on the reinforcing plate. One side perpendicular to the reinforcing plate is an opened wide mouth, through which a wound or laminated electrical core can be parallely filled into the rectangular shell. After the electrical core enters the shell, peripheries of the shell bottom and the rectangular shell's opened wide mouth are welded and sealed. The process of the electrical core entering the shell is performed without extrusion and pressure, and dislocation of anode and cathode pieces will not be caused. By the improvement of the packing structure of the rectangular lithium battery, security hidden danger caused by disadvantages of an assembly technology can be avoided, and safety performance of lithium battery can be raised.

Description

technical field [0001] The invention relates to a lithium battery, in particular to a rectangular lithium battery with an improved packaging structure. Background technique [0002] The existing lithium battery shapes and structures include cylindrical lithium batteries, rectangular lithium batteries, and aluminum-plastic composite film soft-pack lithium batteries. Tight packaging structure sealing, rectangular lithium battery is made of coiled or laminated cells into a rectangular metal shell, sealed by laser welding package structure, aluminum-plastic composite film soft package lithium battery is made of coiled or laminated cells It is sealed by aluminum-plastic composite film through hot-melt packaging structure. These structural forms have their own advantages and disadvantages. Among them, the problem of rectangular lithium battery is particularly prominent in the technical solution of winding or laminating cells into rectangular metal shells. The process of laminatin...

AI Technical Summary

Problems solved by technology

[0002] The existing lithium battery shapes and structures include cylindrical lithium batteries, rectangular lithium batteries, and aluminum-plastic composite film soft-pack lithium batteries. Tight packaging structure sealing, rectangular lithium battery is made of coiled or laminated cells into a rectangular metal shell, sealed by laser welding package structure, aluminum-plastic composite film soft package lithium battery is made of coiled or laminated cells It is sealed by aluminum-plastic composite film through hot-melt packaging structure. These structural forms have their own advantages and disadvantages. Among them, the problem of rectangular lithium battery is particularly prominent in the technical solution of winding or laminating cells into rectangular metal shells. The process of laminating the cell into the rectangular metal shell is to extrude and insert it into the rectangular metal shell, then seal the end cover with laser welding, and wind or laminate to make the cell and the rectangular metal shell. Excessive fit gaps cannot be allowed. Excessive fit gaps will cause the battery core to shake in the rectangular metal shell, resulting in pole piece misalignment. The internal size of the core and the rectangular metal shell does not allow the fit gap to be too small, and the fit gap is too small to be inserted into the rectangular metal shell. During the process of extrusion and insertion of the winding or stacked battery core, the pole pieces of each layer of the battery core are stressed. Can not be completely consistent, especially there is a slidable diaphragm between the positive electrode and the negative electrode. When the positive electrode and negative electrode of the battery core are inconsistent in force, it is easy to cause the positive electrode and negative electrode to be misaligned. The dislocation of the pole piece changes the safety requirements for the negative pole piece to cover the positive pole piece, because once the positive pole piece is not covered by the negative pole piece, the lithium metal dendrite will be formed during the charging and discharging process of the lithium battery. Once the lithium metal dendrite is formed , the diaphragm will be punctured, the diaphragm will be punctured to cause a short circuit, the short circuit will cause heat generation, and even cause a fire and explosion

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