SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2021, Vol. 39 ›› Issue (11): 261-268.DOI: 10.1016/j.cjche.2021.08.020

• Energy Science and Technology • 上一篇    下一篇

Pre-sodiation strategy for superior sodium storage batteries

Yongkai Xu, Haozheng Sun, Cunshuang Ma, Jingjing Gai, Yanhua Wan, Weihua Chen   

  1. Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
  • 收稿日期:2021-04-14 修回日期:2021-08-29 出版日期:2021-11-28 发布日期:2021-12-27
  • 通讯作者: Weihua Chen
  • 基金资助:
    This work is supported by the National Natural Science Foundation of China (Nos. U1804129, 21771164), 2020 College Student Innovation and Entrepreneurship Training Program (202010459004), Zhongyuan Youth Talent Support Program of Henan Province and Zhengzhou University Youth Innovation Program. The authors would like to thank the Center of Advanced Analysis & Gene Sequencing of Zhengzhou University for TGA. DFT calculation was supported by the National Supercomputing Center in Zhengzhou.

Pre-sodiation strategy for superior sodium storage batteries

Yongkai Xu, Haozheng Sun, Cunshuang Ma, Jingjing Gai, Yanhua Wan, Weihua Chen   

  1. Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
  • Received:2021-04-14 Revised:2021-08-29 Online:2021-11-28 Published:2021-12-27
  • Contact: Weihua Chen
  • Supported by:
    This work is supported by the National Natural Science Foundation of China (Nos. U1804129, 21771164), 2020 College Student Innovation and Entrepreneurship Training Program (202010459004), Zhongyuan Youth Talent Support Program of Henan Province and Zhengzhou University Youth Innovation Program. The authors would like to thank the Center of Advanced Analysis & Gene Sequencing of Zhengzhou University for TGA. DFT calculation was supported by the National Supercomputing Center in Zhengzhou.

摘要: The irreversible consumption of sodium in the initial several cycles greatly led to the attenuation of capacity, which caused the low initial coulombic efficiency (ICE) and obvious poor cycle stability. Pre-sodiation can effectively improve the electrochemical performance by compensating the capacity loss in the initial cycle. Here, carbon-coated sodium-pretreated iron disulfide (NaFeS2@C) has been synthesized through conventional chemical method and used in sodium metal battery as a cathode material. The calculated density of states (DOS) of NaFeS2@C is higher, which implies enhanced electron mobility and improved cycle reversibility. Because of the highly reversible conversion reaction and the compensation of irreversible capacity loss during the initial cycle, the Na/NaFeS2@C battery achieves ultra-high initial coulombic efficiency (96.7%) and remarkable capacity (751 mA·h·g-1 at 0.1 A·g-1). In addition, highly reversible electrochemical reactions and ultra-thin NaF-rich solid electrolyte interphase (SEI) also benefit for the electrochemical performance, even at high current density of 100 A·g-1, it still exhibits a reversible capacity of 136 mA·h·g-1, and 343 mA·h·g-1 after 2500 cycles at 5.0 A·g-1. This work aims to bring up new insights to improve the ICE and stability of sodium metal batteries.

关键词: Pre-sodiation, Solid electrolyte interphase, Initial coulombic efficiency, Sodium metal batteries, Interface, Electrochemistry

Abstract: The irreversible consumption of sodium in the initial several cycles greatly led to the attenuation of capacity, which caused the low initial coulombic efficiency (ICE) and obvious poor cycle stability. Pre-sodiation can effectively improve the electrochemical performance by compensating the capacity loss in the initial cycle. Here, carbon-coated sodium-pretreated iron disulfide (NaFeS2@C) has been synthesized through conventional chemical method and used in sodium metal battery as a cathode material. The calculated density of states (DOS) of NaFeS2@C is higher, which implies enhanced electron mobility and improved cycle reversibility. Because of the highly reversible conversion reaction and the compensation of irreversible capacity loss during the initial cycle, the Na/NaFeS2@C battery achieves ultra-high initial coulombic efficiency (96.7%) and remarkable capacity (751 mA·h·g-1 at 0.1 A·g-1). In addition, highly reversible electrochemical reactions and ultra-thin NaF-rich solid electrolyte interphase (SEI) also benefit for the electrochemical performance, even at high current density of 100 A·g-1, it still exhibits a reversible capacity of 136 mA·h·g-1, and 343 mA·h·g-1 after 2500 cycles at 5.0 A·g-1. This work aims to bring up new insights to improve the ICE and stability of sodium metal batteries.

Key words: Pre-sodiation, Solid electrolyte interphase, Initial coulombic efficiency, Sodium metal batteries, Interface, Electrochemistry