锂离子电池不同工况下充电效果对比及用户充电方法选择研究  

Comparison of Charging Effect of Lithium-Ion Battery under Different Working Strategies and Study on User Charging Method Selection

作　　者：孙丙香[1] 李凯鑫 荆龙[1] 苏晓佳 张媛[1] Sun Bingxiang;Li Kaixin;Jing Long;Su Xiaojia;Zhang Yuan(National Active Distribution Network Technology Research Center Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Jiaotong University,Beijing 100044 China;State Grid Jinzhong Power Supply Company,Jinzhong 030600 China)

机构地区：[1]北京交通大学国家能源主动配电网技术研发中心,北京100044 [2]国网晋中供电公司,晋中030600

出　　处：《电工技术学报》2023年第20期5634-5644,共11页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(52177206);装备预研教育部联合基金(8091B022130)资助项目。

摘　　要：合理地选择充电方法对于满足电动汽车用户需求、提高充电效率、延缓电池衰退至关重要。该文以3.6 A·h磷酸铁锂动力电池为研究对象,以30 min内充满电池额定容量的80%为基准,制定了五种不同的电池充电工况。为了适当加速电池的衰退,在45℃下共进行1000个循环实验,以100个循环为间隔,在常温25℃下开展性能实验,对比分析锂离子电池五种充电工况的充电效果,考虑充电起点、等待时间和目标充电容量等需求,合理选择充电工况。对比不同充电工况发现:1000个老化循环后,容量衰退速率最慢的是复合充电工况;导致电池容量衰退的主要原因为正负极活性材料的减少和活性锂离子数量的减少;以起始充电SOC=20%,充电时间为10 min为例,充电能量最大的工况为变电流间歇工况。该文得到的结论为五种典型充电工况的优化选择提供了理论依据。Lithium-ion batteries have become the preferred power source for major car companies due to their superior comprehensive performance and are widely used in electric vehicles.Effectively controlling the battery is crucial to meet the needs of users,improve charging efficiency,and delay battery decline.However,there is no systematic comparative analysis of the charging effect of multiple charging conditions.Because the mainstream BMS is embedded in a single working condition,the optimization selection of charging working conditions is not considered according to the actual needs of different users.Therefore,this paper carries out relevant research on five practical charging conditions.Firstly,five charging strategies were selected,including 1#constant current condition,2#constant power condition,3#five-stage constant current charging condition,4#variable current intermittent charging condition,constant current charging and constant dQ/dV charging combined 5#composite charging condition.The accelerated aging cycle experiment at 45℃was carried out,and performance experiments were carried out at 25℃,including a capacity test and a small rate charge and discharge test.The charging target for cycling experiments under different charging conditions is 80%of the rated capacity of the battery in 30 minutes to be fully charged.Secondly,aiming at the need for a systematic comparative analysis of charging effects under different charging conditions,the following conclusions can be obtained from the analysis of charging capacity,energy consumption,charging energy efficiency,and battery degradation characteristics.The capacity retention rate of composite working conditions after 1000 aging cycle experiments is the highest,which is 91.004%.The energy efficiency in the variable current intermittent condition is the lowest,94.14%,after 1000 cycles,and the highest energy utilization efficiency after 1000 aging cycles is in the constant power condition.In the first 1000 cycles,the battery degradation mechanism is analyzed based

关 键 词：锂离子电池 不同充电工况 容量增量曲线 性能衰退 工况选择 

分 类 号：TM911[电气工程—电力电子与电力传动]