储能科学与技术 ›› 2022, Vol. 11 ›› Issue (12): 3950-3956.doi: 10.19799/j.cnki.2095-4239.2022.0541

• 储能测试与评价 • 上一篇    下一篇

宽温度范围内方形三元锂电池倍率放电性能

张宇杰1(), 汪兴兴1,2(), 朱昱1, 倪红军1, 邓业林2()   

  1. 1.南通大学机械工程学院,江苏 南通 226019
    2.苏州大学轨道交通学院,江苏 苏州 215131
  • 收稿日期:2022-09-22 修回日期:2022-10-11 出版日期:2022-12-05 发布日期:2022-12-29
  • 通讯作者: 汪兴兴,邓业林 E-mail:2009310020@stmail.ntu.edu.cn;wangxx@ntu.edu.cn;yelin.deng@suda.edu.cn
  • 作者简介:张宇杰(1996—),男,硕士研究生,研究方向为动力电池及其应用,E-mail:2009310020@stmail.ntu.edu.cn
  • 基金资助:
    国家自然科学基金项目(51905361);江苏省重点研发计划项目(BE2021065);江苏省高校优势学科建设工程项目

Investigating the rate discharge performance of square ternary lithium batteries at a wide temperature range

Yujie ZHANG1(), Xingxing WANG1,2(), Yu ZHU1, Hongjun NI1, Yelin DENG2()   

  1. 1.School of Mechanical Engineering, Nantong University, Nantong 226019, Jiangsu, China
    2.School of Rail Transportation, Soochow University, Suzhou 215131, Jiangsu, China
  • Received:2022-09-22 Revised:2022-10-11 Online:2022-12-05 Published:2022-12-29
  • Contact: Xingxing WANG, Yelin DENG E-mail:2009310020@stmail.ntu.edu.cn;wangxx@ntu.edu.cn;yelin.deng@suda.edu.cn

摘要:

电动汽车发展前景可观,锂离子动力电池作为其核心部件,在不同工况应用场景中发挥着至关重要的作用。针对方形三元锂电池在宽温度范围内的可用性与安全性,进行了充放电循环实验,研究了锂电池的电压、温度和容量变化规律。通过电压曲线的凹凸性对其开展了分段拟合分析,探索了锂电池处于不同工作状态时的电压平台期特性,结果表明:在10 ℃、25 ℃、40 ℃、55 ℃的环境温度下,以1 C电流倍率放电时电压从3.8 V降至3.1 V期间内;在-20 ℃、-5 ℃的环境温度下,电压分别从3.39 V降至3.05 V、3.68 V降至3.07 V期间内,电压平台期阶段电池端电压变化平缓,表面温升未至峰值,放电容量占比90%左右,电池工作性能较优。而在环境温度降至-35 ℃时电压平台期放电容量仅占总放电容量的66.08%,低温对能量损耗的影响尤其显著。研究结果可为锂离子动力电池在电动汽车能量储存系统中的建模和控制策略设计提供参考依据。

关键词: 电动汽车, 三元锂电池, 放电特性, 分段拟合, 电压平台期

Abstract:

Lithium-ion power batteries are crucial for the development of electric vehicles and they have widespread application in different scenarios. To study the variation laws of the voltage, temperature, and capacity, the charging and discharging cycle experiments are used considering the availability and safety of the square ternary lithium battery in a wide temperature range. According to the concavity and convexity of the voltage curve, the piecewise fitting analysis is performed to explore the voltage plateau characteristics of lithium batteries at different working conditions. The results revealed that, the voltage drops from 3.8 V to 3.1 V at ambient temperatures of 10 ℃, 25 ℃, 40 ℃, and 55 ℃ and current rate of 1 C. Moreover, at the ambient temperature of -20 ℃ and -5 ℃, the voltage drops from 3.39 V to 3.05 V and 3.68 V to 3.07 V, respectively. Furthermore, the battery terminal voltage changes gradually during the voltage plateau period, surface temperature rise does not reach a peak, discharge capacity accounts for approximately 90%, and the battery has excellent operating performance. However, when the ambient temperature drops to -35 ℃, the discharge capacity in the voltage plateau period accounts for 66.08% of the total discharge capacity; moreover, the impact of low temperature on energy loss is substantial. The research results provide a reference for the modeling and control strategy design of lithium-ion power batteries battery in electric vehicle of an energy storage system.

Key words: electric vehicle, ternary lithium battery, discharge characteristic, piecewise fit, voltage plateau period

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