Based on the variation of battery cycle attenuation under electrothermal coupling

With the economic and social development, the demand for energy is increasing globally, and the environmental problems are becoming more serious, and the massive use of fossil energy such as oil can cause greater environmental pollution problems, in order to reduce environmental pollution and the greenhouse effect, the development of electric vehicles and power batteries are getting more and more attention from the society. Based on the above background, in order to improve the economic and social benefits of electric vehicles, researchers have conducted a large number of related studies on the performance of power batteries. This paper carries out a simulation and analysis study on the performance change of lithium battery under typical working conditions under thermoelectric multi-coupling factors. In this paper, three-dimensional modeling is carried out based on the working characteristics of lithium batteries, which electrochemical model will be used P2D (pseudo two dimensional, P2D) model theory. The main research content of this paper and the results to be obtained are as follows: the use of COMSOL Multiphysics software platform for lithium-ion batteries to establish a three-dimensional electrochemical thermal coupling model; on this basis, through the relevant experimental data, to verify the authenticity and feasibility of the simulation model; the use of the simulation model for the simulation and analysis of the battery performance degradation, to obtain the multi-factorial coupling of heat, electricity, the performance of lithium battery degradation data and patterns. The simulation model is used to simulate and analyze the battery performance degradation to obtain the performance degradation data and law of lithium battery under multi-factor coupling of heat and electricity. Based on the above background, in order to improve the economic and social benefits of electric vehicles, researchers have conducted a large number of related studies on the performance of power batteries. This paper focuses on the influence of different charging and discharging rates on battery performance under normal temperature conditions. It is found that the battery decay rate is the lowest at 0.2C charging rate, and the battery decay rate is the highest at 2C charging rate, which significantly accelerates the battery decay. The charging ratio of 1C is a more optimized choice.