Theoretical And Experimental Research On Precision Manufacturing Of Power Lithium Ion Battery Electrode

In recent years,oil and other fossil energy shortage caused by the energy crisis and environmental pollution caused by the use of fossil fuels has seriously affected the development of human society.Electric vehicles become the current developing tendency,because of its energy conservation and environment friendly.Power lithium ion battery has attracted people's attention,as the core power components of electric vehicles.The thickness consistency of the single battery electrode has an important influence on the performance and stability of the power battery,Electrode rolling technic is one of the key technics in the manufacture of battery electrode.Thus,it is important to study the technic of electrode rolling for improving the performance of pole piece.In this paper,two methods are used to analyze the rolling process of the battery electrode.Firstly,the rolling principle and the key parameters related to electrode rolling are discussed.Secondly,the effect of the changes of the roll system parameters on the thickness consistency of two roll mill is studied,on account elastic-plastic FEM.Four roll mill roll finite element pattern was established with the equivalent of the two roll mill.The feasibility of four roll mill instead of two roll mill for rolling the battery electrode is discussed.The influence of four roll mill roller parameters variation on the thickness consistency is analyzed.Finally,the effect of rolling reduction ratio,coating thickness,rolling pass and rolling temperature on the performance of electrode and LiFePO4 battery was studied by experiments.The results show that,when the two roll mill roll length is constant,the thickness uniformity of electrodes is improved with the increase of roll length and bending roll force.The four high mill instead of two high mill has the feasibility of rolling power lithium ion battery electrode.With the increase of four high mill working roll diameter and supporting roll diameter,electrodes thickness uniformity along the width direction is improved.With the increase of working roll bending force,electrodes thickness uniformity along the width direction and rolling width are improved,it can improve the problem that electrode rolling width is too narrow in actual production.When the rolling number is 3,rolling degree is 160°C,battery electrode has better performance.When the coating thickness is 100?m,rolling reduction rate is 50%,rolling number is 3,rolling degree is 160°C,lithium ion battery has better comprehensive performance.The research results can offer some references and data for technical research and field production.