Research And Optimization Of The Lithium-ion Battery Cell Drying Equipment

The cell drying process occupies a very important position in the production process of lithium-ion battery,while the existing domestic cell dryers are mostly semi-automatic processes with manual participation,low work efficiency,poor sealing performance and unsatisfying cell drying uniformity,there has been a big gap compared with the fully automated equipment used abroad.Therefore,this paper analyzed the drying process of the existing lithium-ion battery cells,based on which a reasonable process flow was designed and a automatic lithium ion battery cell drying equipment with automatic access to materials,high sealing performance,uniform drying effect was proposed.The main studies were as follows:1.Proposed the cell vacuum drying process and gas cycle program.The moisture composition and drying mechanism of the cell were analyzed,and a new process scheme of cell vacuum drying was designed.2.Proposed the overall program of the cell drying equipment and carried out a detailed structural design of the various parts.3.The key parts of the cell drying equipment with sealing performance were confirmed and the theoretical analysis and simulation calculation were carried out.Because the strength of the pressure-bearing element-rectangular large-opening box can not be calculated by the traditional theoretical calculation,the strength of the box is simulated and analyzed by ANSYS.The kinematic analysis of the gate in the door and window part was carried out,and the completion of its tight seal was verified.The process of the sealing strip compressing and sealing the gate and the vacuum pump vacuuming the interior of the box were analyzed.The results showed that the rectangular sealing strip was more suitable for the structure.And the overall deformation distribution was also analyzed.4.According to the numerical simulation results,the parameters that affect the drying uniformity were optimized based on the cell drying equipment.A gas flow model inside the battery oven was established.The numerical simulation of the wind speed field inside the oven was carried out by Fluent software,and a uniform index for the device was designed.The orthogonal experiment was designed based on the structural parameters and operating parameters respectively,and the range analysis was made to determine the degree of the importance of each factor on the uniformity.The optimal combination of the parameters was found.The structure of the air inlet and the drying uniformity of the drying chamber were both improved.5.Verified the drying effect of new equipment.The Fluent software was used to simulate the internal water content of the batteries at the end of drying time,and comparing the result with the internal water content of the batteries in the old equipment measured by Coulom method,the drying effect of the new equipment was verified.