| Lithium ion batteries have light weight,large capacity,no memory,small selfdischarge coefficient,environmental advantages and etc,so it becomes the first energy of various kinds of electronic devices,especially it is the new energy vehicle field.A clear outlook for lithium batteries is made in the roadmap for techn ological development of China's Y2025 key areas launched in China.The energy density of the energy type lithium battery must be greater than 300Wh/kg,Lithium battery has risen to the focus of national strategic research,and it has become the key to China 's overtaking in the automotive industry.Formation process is a key procedure during the lithium cells manufacturing,By activating the positive and negative electrode materials,the Li ion battery could form a good SEI film which could improve the cycle performance and service life of the battery.If you want to make it,a proper formation equipment is necessary.Currently,there are common problems about lithium battery formation equipment at home and abroad,such as small formation current,formation temperature is out of control,cell formation without pressure.To solve these problems,this paper designs a monitoring and management system into constant temperature and pressure with jig,to evaluate the performance of the battery that produced by this s ystem.The main tasks are as followings:Firstly,by reading various articles and documents at home and abroad,be familiar with the performance parameters of each formation equipment,visiting different formation equipment manufacturers or lithium batteries manufacturing enterprise.fully understand the chemical equipment and process at home and abroad.a comprehensive review of the formation equipment at home and abroad is given.The thesis summarizes the advantages and disadvantages of the formation equipment and the formation process,and some common problems in the process of lithium battery formation.Secondly,in this paper,the constant chemical pressure technique is used to shorten the distance between the cathode,the negative electrode and the separator of the lithium battery,so as to reduce the distance of the lithium ion formation.Increasing the formation temperature and keeping the temperature constant,it can enhance the activity of positive electrode,negative electrode,electrolyte and other materials,reduce the resistance of lithium ion crossing the material,and the lithium battery is formed to form a dense and stable SEI film,exhibiting a smaller internal resistance of the battery.The safety performance,cycle life and battery usage of the battery are greatly improved.When lithium batteries are formed,they can have higher formation current,save time and increase production efficiency,while the appearance of the battery becomes more flat,thinner,and the volume capacity ratio is also improved accordingly.Thirdly,the system development of the lower computer is realized.In order to improve the formation current,through the investigation and study of the pressure sensing mode which is widely used in industry,included the mechanical transmission,electric drive,hydraulic transmission,pneumatic transmission and so on,the pressure sensing mode of cylinder drive is determined,and the cylinder parameters are determined,and the constant pressure of the battery in the process of formation is realized.Then various factors that influence battery formation performance are determined by brainstorming,and found the importance of various factors by fishbone diagram,finally make sure the key factors by the Taguchi design method for the optimal formation conditions.Finally,combined with SQL Server database and Visual Basic programming tools,the host computer operating system was planned and designed.Designed a kind of operating software with simple operation,high man-machine interactivity and stable running system,to realize core functions such as formation monitoring,process controlling,data storage,data query and statistics analysis for lower compute storage. |
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