Study On Liquid Sealing Technology Of Soft Lithium Battery Under Negative Pressure

At present,the quality and efficiency of liquid injection sealing is an important factor affecting the quality and production efficiency of lithium batteries in the traditional liquid injection sealing technology of soft-packed lithium batteries.In order to improve the quality and efficiency of lithium batteries’ injection sealing,this paper puts forward a method of processing the injection and sealing in the same negative pressure environment to avoid the impurities such as air infiltrating into the core during the transfer process between the injection and sealing equipment,so as to ensure the quality of lithium batteries and improve the production efficiency.Specific research contents are as follows:1.Study the injection and sealing technology of soft-pack lithium battery.The factors affecting the infiltration efficiency of electrolyte were analyzed,and the injection method with positive and negative pressure circulation was determined.This paper analyzes the factors influencing the quality of aluminum plastic film heat sealing,simulates the temperature and deformation of the heat sealing roller by controlling variables,and determines the optimal heat-sealing temperature,heat-sealing pressure and heat-sealing time,so as to minimize the deformation of the heat sealing roller and ensure the quality of heat sealing.2.The liquid injection sealing device for soft-packed lithium battery is designed with modular design method.According to the function,the equipment is divided into several modules,and combined with the liquid injection and sealing process,the structure design of the cell conveying module,negative pressure liquid injection module and negative pressure sealing module is carried out,and the simulation and optimization design of the hot sealing roller of the sealing module is carried out.3.Failure analysis of liquid injection sealing equipment for soft-pack lithium battery.In order to improve the reliability of equipment,the reverse fishbone diagram was used to model each mechanism,and the failure mode in the mechanism was obtained by reverse questioning,and the confirmed failure mode in the system was screened out.Failure modes are analyzed and prioritized by ELRPN method,so as to obtain important failure modes in the system.4.Apply TRIZ principle to improve the important failure modes in the system.Through the40 principles of invention and the matter-field model in TRIZ,the improvement scheme was proposed for the failure mode,and the optimal scheme was compared and selected.The improved system was obtained through the comprehensive scheme,and the failure analysis and improvement were carried out again to determine the final optimized system.