储能科学与技术 ›› 2024, Vol. 13 ›› Issue (7): 2141-2150.doi: 10.19799/j.cnki.2095-4239.2024.0375

• 低温电池专刊 • 上一篇    下一篇

硬碳动力学特性对钠离子电池低温性能的影响及机制

徐雄文1,2(), 莫英1(), 周望1, 姚环东2, 洪娟2, 雷化2, 涂健2, 刘继磊1()   

  1. 1.湖南大学材料科学与工程学院,湖南 长沙 410082
    2.湖南立方新能源科技有限责任公司,湖南 株洲 412000
  • 收稿日期:2024-05-06 修回日期:2024-05-29 出版日期:2024-07-28 发布日期:2024-07-23
  • 通讯作者: 刘继磊 E-mail:xavixu@lifuntech.com;yingmo@hnu.edu.cn;liujilei@hnu.edu.cn
  • 作者简介:徐雄文(1984—),男,博士研究生,高级工程师,研究方向为锂(钠)离子电池,E-mail:xavixu@lifuntech.com
    莫英(1998—),女,博士研究生,研究方向为钠离子电池硬碳负极,E-mail:yingmo@hnu.edu.cn
  • 基金资助:
    岳麓山工业创新中心重点项目(2023YCII0119)

Effect of hard carbon kinetic properties on low-temperature performance of Na-ion batteries

Xiongwen XU1,2(), Ying MO1(), Wang ZHOU1, Huandong YAO2, Juan HONG2, Hua LEI2, Jian TU2, Jilei LIU1()   

  1. 1.School of Materials Science and Engineering, Hunan University, Changsha 410082, Hunan, China
    2.LI -FUN Technology Corporation Limited, Zhuzhou 412000, Hunan, China
  • Received:2024-05-06 Revised:2024-05-29 Online:2024-07-28 Published:2024-07-23
  • Contact: Jilei LIU E-mail:xavixu@lifuntech.com;yingmo@hnu.edu.cn;liujilei@hnu.edu.cn

摘要:

以磷酸焦磷酸铁钠(NFPP)为正极,硬碳(HC)为负极,制作了软包钠离子电池,研究了不同动力学性能的硬碳对钠离子电池循环性能和低温性能的影响。借助电化学交流阻抗谱(EIS)、弛豫时间分析技术(DRT)以及恒电流间歇滴定技术(GITT)等分析手段对比研究了不同硬碳的电荷转移阻抗、SEI阻抗以及扩散系数大小,得到了动力学性能趋势:HC-A>HC-C>HC-B。结果表明,硬碳的动力学性能直接影响到钠离子电池的循环性能和低温放电性能。动力学性能最优的生物质硬碳HC-A不仅可以支持室温下5C快速充电并且循环容量几乎无衰减,还表现出良好的低温性能,可以在0 ℃下0.5C充电和-10 ℃下0.2C充电并稳定循环,在-30 ℃下0.5C放电容量百分比达87.5%。动力学性能最差的树脂基硬碳HC-B无法支持15 ℃下0.5 C循环,且-30 ℃下0.5C放电容量百分比仅有83.7%。针对HC-B低温性能差的问题,提高电池设计的N/P比可以显著改善钠离子电池的低温性能,使得电池在-10 ℃下可以支持0.1C充电并稳定循环100圈,容量保持率几乎无变化。本工作对钠离子电池的设计优化和低温性能改进具有重要的参考价值。

关键词: 钠离子电池, 硬碳, 低温性能, 动力学, N/P比

Abstract:

Pouch-type Na-ion batteries were fabricated using a Na4Fe3(PO4)2P2O7 cathode and hard carbon (HC) anodes obtained from different sources: biomass-derived (HC-A), resin-derived (HC-B), and biomass-derived (HC-C). The effect of the HC anode on the cycling durability and low-temperature performance was investigated. The charge transfer impedance, solid electrolyte interphase impedance, and diffusion coefficient values were determined for the three HC anodes by electrochemical impedance spectroscopy, distribution of relaxation times, and galvanostatic intermittent titration technique. The kinetic properties, which directly affect the battery performance, showed the following trend: HC-A > HC-C > HC-B. The best cycling durability was obtained with HC-A, which was stable at room temperature with 5C fast charging and -10 ℃ with 0.2C charging. In addition, a capacity ratio of 87.5% was achieved with a 0.5C discharge at -30 ℃. The HC-B anode led to the lowest kinetic performance; it failed when cycling at 15 ℃ with 0.5C charging, and the capacity ratio was only 83.7% with a 0.5C discharge at -30 ℃. The low-temperature performance of the battery using HC-B was significantly improved by increasing the N/P ratio of the battery. After 100 cycles at -10 ℃ with 0.1C charging, the capacity retention remained stable at about 104%. This work represents an important foundation to improve the design of Na-ion batteries.

Key words: Na-ion battery, hard carbon, low temperature performance, kinetic property, N/P ratio

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