Lithium ion battery

Abstract

The invention relates to a lithium ion battery, which comprises a shell and a one-way valve, wherein a through hole is formed in the shell, the one-way valve penetrates through the through hole, a sealing piece is arranged between the one-way valve and the through hole, and the opening condition of the one-way valve is that the internal air pressure of the lithium ion battery is 0.5-0.8MPa; the one-way valve can be opened when the air pressure in the battery is abnormal, the gas in the battery is exhausted through the one-way valve, and the internal air pressure of the lithium ion battery is maintained within a proper range, so that the problem of local lithium precipitation caused by abnormal air pressure generated by side reaction in the lithium ion battery is solved, the cycle performance of the lithium ion battery is improved, and the service life of the lithium ion battery is prolonged.

Description

technical field [0001] The invention belongs to the technical field of energy storage devices and relates to a lithium ion battery. Background technique [0002] The charging and discharging process of the secondary battery requires the participation of the electrolyte and the electrode. In the process, the side reaction between the electrolyte and the electrode inevitably occurs, and abnormal gas is generated. The abnormal gas is squeezed inside the battery and exists between the positive and negative electrodes. Therefore, the gas production inside the cell is an important factor affecting the cycle life of the cell, and also affects the service life of the entire secondary battery. [0003] CN108666538A discloses a lithium ion battery, which includes: a housing, an anode, a cathode, a diaphragm and electrolyte, the anode, cathode, diaphragm and electrolyte are packaged inside the housing, the anode and The cathode is arranged at intervals through a diaphragm, the anode i...

AI Technical Summary

Problems solved by technology

[0002] The charging and discharging process of the secondary battery requires the participation of the electrolyte and the electrode. In the process, the side reaction between the electrolyte and the electrode inevitably occurs, and abnormal gas is generated. The abnormal gas is squeezed inside the battery and exists between the positive and negative electrodes. Therefore, the gas production inside the cell is an important factor affecting the cycle life of the cell, and also affects the service life of the entire secondary battery.

[0003] CN108666538A discloses a lithium ion battery, which includes: a housing, an anode, a cathode, a diaphragm and electrolyte, the anode, cathode, diaphragm and electrolyte are packaged inside the housing, the anode and The cathode is arranged at intervals through a diaphragm, the anode includes a 3D carbon nanotube sponge and a plurality of transition metal oxide particles, and the carbon nanotube sponge is a honeycomb structure formed by interconnecting a plurality of carbon nanotubes , the carbon nanotube sponge body includes a plurality of micropores, the pore diameter of the micropores is greater than or equal to 5 microns; the plurality of transition metal oxide particles are uniformly attached to the surface of the carbon nanotubes and located in the micropores, the plurality of The particle size of each transition metal oxide particle is less than or equal to 200 nanometers. This solution does not provide a method for solving the problem of abnormal air pressure inside the lithium-ion battery and the shortening of the life of the lithium-ion battery caused by local lithium precipitation inside the battery.

In this way, by arranging multiple micro-groove structures on the negative electrode sheet and the positive electrode sheet, the electrolyte can be better absorbed, and the positive electrode sheet and the negative electrode sheet can be fully infiltrated, which reduces the internal resistance of the battery and improves the internal conduction of electrons in the lithium-ion battery. The efficiency, and the micro-groove structure can better embed lithium ions, greatly improving the capacity and cycle performance of lithium-ion batteries, but this solution does not give how to solve the abnormal internal pressure of lithium-ion batteries and cause local analysis of the battery. Lithium-induced approach to the problem of shortened lithium-ion battery life

[0006] Therefore, it is still of great significance to develop a lithium-ion battery that can reduce the shortened battery life caused by abnormal air pressure inside the lithium-ion battery.

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