Development Of Battery Structure And System Of Electric Vehicle

With the development of new energy vehicles in China,the technical level has been greatly developed,the new energy automotive technology system with independent intellectual property rights has been established.Compared with the traditional car,the new energy vehicle uses the battery as the energy source.It can achieve zero pollution and zero emission in the whole driving process.Even though the future of lithium batteries are faced with the problem of recycling,but the lithium battery itself is small and easy to focus on pollution treatment.Combustion engine exhaust is very difficult to focus on treatment,as one of the important sources of haze in our country in recent years.Power battery in the pure electric vehicle is the only power source of the driving system,mainly fuel cells,nickel metal hydride and lithium ion batteries,etc..Its characteristics must meet the requirements of electric vehicle driving,safety performance.Battery cell and system design have strict requirements in the battery temperature,cycle performance,battery power characteristics,the structural strength,BMS protection and control.This thesis takes Changan M201 pure electric vehicle as the research object,and studied the power battery system of electric vehicle,Using materials science,mechanical design and computer simulation analysis method design the power battery system which meets the requirements of the pure electric vehicle driving and charging requirements.The main innovative accomplishments in this dissertation can be concluded as follows:Ⅰ、Selection of positive electrode and negative electrode material for battery cell and optimization of its structure and safety.By comparing the current main power battery industry development overview,grasp industry trends for the problem of power battery,optimize material selection and matching principle to get the best combination of materials collocation.To solve the cell problem in safety,difference and consistency,and complete the electrical performance test of the designed cell.Ⅱ、Arrangement of battery system overall planning and design of the battery module and box structure.National requirements for the battery system must meet five years or one hundred thousand kilometers of life,structure design is a very important part of the design,including the battery box,battery module,high pressure system layout,sealing insulation design,etc.According to the project performance index requirements,design system to meet the relevant requirements of electrical appliances.For the design of the system structure,useing simulation software to simulate the random vibration strength,and further optimize the design of the program。Ⅲ、Circuit and function design of BMS protection board for battery management system.BMS protection management system is essential for the safety and reasonable operation of the power battery pack and the execution of the vehicle energy management strategy.According to the actual working condition of the battery system,reasonable protection strategy is made to monitor the battery voltage,temperature,and current of the battery system,The upper and lower limit of system protection is set up,and promoted the life of the system.Ⅳ、Power battery system function test.The performance test of the battery system is carried out,such as the normal temperature charge discharge capacity,the high low temperature discharge capacity,the capacity of continuous discharge,the maximum pulse charge capacity and charge and discharge energy efficiency.