Lithium-ion power battery

Abstract

The invention relates to a lithium-ion power battery, comprising a laminated battery cell (16). The laminated battery cell (16) comprises negative pole pieces (9), positive pole pieces (10) and insulating diaphragms (7), wherein, the negative pole pieces (9) and the positive pole pieces (10) are sequentially arrayed at intervals and are separated by the insulating diaphragms (7); the negative pole pieces (9) are all connected with negative pole lug connectors (21) by fixing parts (20); the positive pole pieces (10) are all connected with positive pole lug connectors (22) by the fixing parts (20); paper clip films (8) are filled between the positive pole pieces (10) and the insulating diaphragms (7) connected at both sides; the paper clip films (8) are filled between the outermost insulating diaphragm (7) and the outermost negative pole piece (9); a heat conduction film (6) is filled outside the outermost insulating diaphragm (7). The lithium-ion power battery features lower internal resistance, high discharge rate, high charge efficiency, long cycle life and high safety.

Description

technical field [0001] The invention relates to a rechargeable battery, in particular to a lithium-ion power battery, which belongs to the field of power batteries and is mainly used in various hybrid vehicles and pure electric vehicles using lithium-ion power batteries as power sources. Background technique [0002] At present, there are two main structures of lithium-ion power batteries. One is a rolled-type lithium-ion power battery in which the rolled batteries are packaged in a circular or square casing, but the heat dissipation of the batteries during the working process of this battery is only Relying on the gas convection exchange in the internal space and the heat conduction of a very small part of the medium, this structure cannot effectively solve the heat dissipation problem, which makes this structure unable to achieve a large capacity (only about 10Ah) lithium-ion power battery . Even if some manufacturers can increase the capacity, the battery capacity will q...

AI Technical Summary

Problems solved by technology

The insulating diaphragm has the insulating properties of isolating electrons and the ability to absorb and hold liquid. The current laminated lithium-ion power battery has the following defects: (1) The electrolyte is easy to volatilize, resulting in a low electrolyte holding rate of the insulating diaphragm. , the amount of electrolyte adsorbed on the insulating diaphragm of the laminated battery cell is small, which makes the lithium-ion power battery generate activation resistance, resulting in relatively high internal resistance and low discharge rate, which makes the lithium-ion power battery heat or damage, and the charging efficiency decreases. The service life is reduced; (2), the problem of temperature rise and heat generation of the existing laminated lithium-ion power battery has not been solved ideally, which also causes the shortening of the battery cycle life

Therefore, in order to further improve the quality of lithium-ion power batteries, it is necessary to solve the problems of low electrolyte holding rate and battery heat dissipation on the insulating diaphragm of laminated cells, but this has always been a difficult problem that cannot be solved fundamentally.

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