Comparison of Charging Effect of Lithium-Ion Battery under Different Working Strategies and Study on User Charging Method Selection
Sun Bingxiang1, Li Kaixin2, Jing Long1, Su Xiaojia1, Zhang Yuan1
1. National Active Distribution Network Technology Research Center Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Jiaotong University Beijing 100044 China; 2. State Grid Jinzhong Power Supply Company Jinzhong 030600 China
Abstract:Lithium-ion batteries have become the preferred power source for major car companies due to their superior comprehensive performance, and are widely used in the field of electric vehicles. How to effectively control the battery, especially the reasonable choice of charging method is crucial to meet the needs of users, improve charging efficiency, and delay battery decline.However, at present, there is no systematic comparative analysis of the charging effect of multiple charging conditions, and 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, the specific content is as follows: Firstly, in a variety of charging conditions, 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 five charging strategies were selected to carry out accelerated aging cycle experiment at 45 °C, and performance experiments were carried out at 25°C, including capacity test and 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 lack of systematic comparative analysis of charging effects under different charging conditions, from the analysis of charging capacity, energy consumption, charging energy efficiency and battery degradation characteristics, the following conclusions can be obtained: the capacity retention rate of composite working conditions after 1000 aging cycle experiments is the highest, which is 91.004%; Analyzing the energy consumption and energy utilization efficiency of the battery, it is found that 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 1 000 cycles, the battery degradation mechanism is analyzed based on the IC curve, and it is found that the main reasons for the battery capacity decline are the loss of active materials in the positive and negative electrodes and the decrease in the number of active lithium ions. Finally, in view of the problem that the charging condition is not selected based on user needs, the charging starting point, waiting time and target charging capacity are considered to optimize the charging condition. According to the analysis of experimental results, it is found that when the charging starting SOC=0%, taking the battery charging capacity as the evaluation standard, charging for 20min, the optimal working condition is the five-stage constant current or variable current intermittent working condition. When the initial charge SOC=20% and the charging time is 15min or less, intermittent charging of variable current is the optimal operating condition. Considering the 20% SOC interval, the SOC interval is different, and the optimal working conditions are different, for example, the 0~20% SOC interval should use the five-stage constant current working condition, and the 20~40%SOC and 40~60%SOC interval are suitable for the variable current intermittent working condition.
孙丙香, 李凯鑫, 荆龙, 苏晓佳, 张媛. 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[J]. 电工技术学报, 0, (): 71-71.
Sun Bingxiang, Li Kaixin, Jing Long, Su Xiaojia, Zhang Yuan. Comparison of Charging Effect of Lithium-Ion Battery under Different Working Strategies and Study on User Charging Method Selection. Transactions of China Electrotechnical Society, 0, (): 71-71.
[1] 韩雪冰, 欧阳明高, 卢兰光, 等. 电动车磷酸铁锂电池衰减后开路电压特性分析[J]. 电源技术, 2015, 39(9): 1876-1878. Han Xuebing, Ouyang Minggao, Lu Languang, et al.Characteristics analysis of open circuit voltage of aged LiFePO4 battery for electric vehicle[J]. Chinese Journal of Power Sources, 2015, 39(9): 1876-1878. [2] 王义军, 左雪. 锂离子电池荷电状态估算方法及其应用场景综述[J].电力系统自动化, 2022, 46(14): 193-207. Wang Yijun, Zuo Xue.Review on estimation methods for state of charge of Lithium-ion battery and their application scenarios[J]. Automation of Electric Power Systems, 2022, 46(14): 193-207. [3] Dubarry M, Truchot C, Liaw B Y.Synthesize battery degradation modes via a diagnostic and prognostic model[J]. Journal of Power Sources, 2012, 219: 204-216. [4] Ouyang Minggao, Chu Zhengyu, Lu Languang, et al.Low temperature aging mechanism identification and lithium deposition in a large format lithium iron phosphate battery for different charge profiles[J]. Journal of Power Sources, 2015, 286: 309-320. [5] Zhang S S.The effect of the charging protocol on the cycle life of a Li-ion battery[J]. Journal of Power Sources, 2006, 161(2): 1385-1391. [6] 吴晓刚, 崔智昊, 孙一钊, 等. 电动汽车大功率充电过程动力电池充电策略与热管理技术综述[J]. 储能科学与技术, 2021, 10(6): 2218-2234. Wu Xiaogang, Cui Zhihao, Sun Yizhao, et al.Charging strategy and thermal management technology of power battery in high power charging process of electric vehicle[J]. Energy Storage Science and Technology, 2021, 10(6): 2218-2234. [7] 王榘, 熊瑞, 穆浩. 温度和老化意识融合驱动的电动车辆锂离子动力电池电量和容量协同估计[J]. 电工技术学报, 2020, 35(23): 4980-4987. Wang Ju, Xiong Rui, Mu Hao.Co-estimation of lithium-ion battery state-of-charge and capacity through the temperature and aging awareness model for electric vehicles[J]. Transactions of China Electrotechnical Society, 2020, 35(23): 4980-4987. [8] Spingler F B, Wittmann W, Sturm J, et al.Optimum fast charging of lithium-ion pouch cells based on local volume expansion criteria[J]. Journal of Power Sources, 2018, 393: 152-160. [9] Zhang Caiping, Jiang Jiuchun, Gao Yang, et al.Charging optimization in lithium-ion batteries based on temperature rise and charge time[J]. Applied Energy, 2017, 194: 569-577. [10] Mohamed, Abdel-Monem,. Influence analysis of static and dynamic fast-charging current profiles on ageing performance of commercial lithium-ion batteries[J]. Energy, 2017, 120: 179-191. [11] 杨帆, 乔艳龙, 甘德刚, 等. 不同充电模式对锂离子电池极化特性影响[J]. 电工技术学报, 2017, 32(12): 171-178. Yang Fan, Qiao Yanlong, Gan Degang, et al.Lithium-ion battery polarization characteristics at different charging modes[J]. Transactions of China Electrotechnical Society, 2017, 32(12): 171-178. [12] Mohamed Monem A, Trad Khiem, Omar Noshin, et al.Lithium-ion batteries: evaluation study of different charging methodologies based on aging process[J]. Applied Energy, 2015, 152: 143-155. [13] 劳力. 高比能锂离子动力电池系统充电策略及热失控安全研究[D]. 合肥: 中国科学技术大学, 2020. [14] 周旋, 周萍, 郑岳久, 等. 锂离子电池宽温度区间无析锂快充策略[J]. 汽车安全与节能学报, 2020, 11(3): 397-405. Zhou Xuan, Zhou Ping, Zheng Yuejiu, et al.Strategy of fast charging of lithium-ion batteries without lithium plating in a wide temperature range[J]. Journal of Automotive Safety and Energy, 2020, 11(3): 397-405. [15] Birkl C R, Roberts M R, McTurk E, et al. Degradation diagnostics for lithium ion cells[J]. Journal of Power Sources, 2017, 341: 373-386. [16] Billy Wu,Vladimir Yufit,Yu Merla.Differential thermal voltammetry for tracking of degradation in lithium-ion batteries[J]. Journal of Power Sources, 2015, 273: 495-501. [17] Devie A, Dubarry M, Liaw B Y.Overcharge study in Li4Ti5O12Based lithium-ion pouch cell[J]. Journal of the Electrochemical Society, 2015, 162(6): A1033-A1040. [18] Gao Yang, Jiang Jiuchun, Zhang Caiping.Lithium-ion battery aging mechanisms and life model under different charging stresses[J]. Journal of Power Sources, 2017, 356: 103-114. [19] 于维珂, 汪涛, 杨尘. 储能用锂离子电池充放电能量效率的影响因素[J]. 电池, 2020, 50(6): 552-555. Yu Weike, Wang Tao, Yang Chen.Influence factors of charge-discharge energy efficiency of Li-ion battery for energy storage[J]. Battery Bimonthly, 2020, 50(6): 552-555. [20] Padhi A K, Nanjundaswamy K S, Goodenough J B.Phospho-olivines as positive-electrode materials for rechargeable lithium batteries[J]. Journal of the Electrochemical Society, 1997, 144(4): 1188-1194. [21] 杨胜杰, 罗冰洋, 王菁, 等. 基于容量增量曲线峰值区间特征参数的锂离子电池健康状态估算[J]. 电工技术学报, 2021, 36(11): 2277-2287. Yang Shengjie, Luo Bingyang, Wang Jing, et al.State of health estimation for lithium-ion batteries based on peak region feature parameters of incremental capacity curve[J]. Transactions of China Electrotechnical Society, 2021, 36(11): 2277-2287. [22] Matthieu Dubarry, Bor Yann Liaw.Identify capacity fading mechanism in a commercial LiFePO4 cell[J]. Journal of Power Sources, 2009, 194(1): 541-549. [23] Zhang Caiping, Jiang Jiuchun, Zhang Linjing, et al.A generalized SOC-OCV model for lithium-ion batteries and the SOC estimation for LNMCO battery[J]. Energies, 2016, 9(11): 900. [24] Dubarry M,Truchot C,Liaw B Y.Evaluation of commercial lithium-ion cells based on composite positive electrode for plug-in hybrid electric vehicle applications. Part I: Initial characterizations[J]. Journal of Power Sources, 2011, 196(23): 10328-10335. [25] 王振新, 秦鹏, 康健强, 等. 基于衰退机理的三元锂离子电池SOH的诊断与估算[J]. 电子测量技术, 2020, 43(10): 7-13. Wang Zhenxin, Qin Peng, Kang Jianqiang, et al.SOH diagnosis and estimation for NCM lithium-ion batteries based on degradation mechanism[J]. Electronic Measurement Technology, 2020, 43(10): 7-13. [26] 孙丙香, 任鹏博, 陈育哲, 等. 锂离子电池在不同区间下的衰退影响因素分析及任意区间的老化趋势预测[J]. 电工技术学报, 2021, 36(3): 666-674. Sun Bingxiang, Ren Pengbo, Chen Yuzhe, et al.Analysis of influencing factors of degradation under different interval stress and prediction of aging trend in any interval for lithium-ion battery[J]. Transactions of China Electrotechnical Society, 2021, 36(3): 666-674. [27] 孙丙香, 刘佳, 韩智强, 等. 不同区间衰退路径下锂离子电池的性能相关性及温度适用性分析[J]. 电工技术学报, 2020, 35(9): 2063-2073. Sun Bingxiang, Liu Jia, Han Zhiqiang, et al.Performance correlation and temperature applicability of Li-ion batteries under different range degradation paths[J]. Transactions of China Electrotechnical Society, 2020, 35(9): 2063-2073.