Method for judging infiltration state of lithium ion battery

Abstract

The invention discloses a method for judging the infiltration state of a lithium ion battery. The method comprises the following steps of: establishing a functional relation of a battery cell infiltration state S, shelving time t, temperatures T1, T2 and T3 of a temperature field under different battery cell radiuses and a mean temperature T of the temperature field; placing a battery cell produced by a production line in a drying oven, and recording the shelving temperature and the shelving time t; respectively collecting and recording the temperatures T1, T2 and T3 of the temperature field and the mean temperature T of the temperature field under different radiuses by using an infrared thermal imager by taking the center of the intersection point of the transverse axis and the longitudinal axis of the battery cell as an original point; and measuring and calculating the infiltration state S of the battery cell under different parameters according to the functional relation so as to detect the infiltration effect of the battery cell. According to the method, the infiltration state of the battery is judged through the temperature gradient distribution in the lithium ion battery by utilizing the correlation between the thermal conductivity of the battery cell and the infiltration condition of the liquid electrolyte in the battery cell, so that the disassembly damage to the battery cell is effectively avoided, the operation is simple, and the credibility is high.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, in particular to a method for judging the infiltration state of lithium ion batteries. Background technique [0002] With the strong support and promotion of the new energy industry by the state, lithium-ion batteries are favored by people due to their high energy density, long cycle life, environmental friendliness, safety and pollution-free, and are widely used in the fields of energy storage and power. Especially as a power battery, it is applied to various pure electric vehicles and hybrid vehicles, and has become one of the indispensable power sources for modern vehicles. [0003] With the rapid expansion and development of the application range of lithium-ion batteries, the market's requirements for lithium-ion batteries are becoming more and more stringent, especially for their energy density, cycle life and safety. At the same time, in the production and preparation process of ...

AI Technical Summary

Problems solved by technology

At the same time, in the production and preparation process of lithium-ion batteries, incomplete and uneven infiltration of the cell electrode will lead to a significant decline in the cycle performance and safety of the cell, especially in the process of cell formation. If the core is not fully formed, the electrical performance will be significantly reduced, and it will affect the quality and consistency of the battery

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