Surface modification using heptafluorobutyric acid to produce highly stable Li metal anodes

Yuxiang Xie; Yixin Huang; Yinggan Zhang; Tairui Wu; Shishi Liu; Miaolan Sun; Bruce Lee; Zhen Lin; Hui Chen; Peng Dai; Zheng Huang; Jian Yang; Chenguang Shi; Deyin Wu; Ling Huang; Yingjie Hua; Chongtai Wang; Shigang Sun

doi:10.1038/s41467-023-38724-x

Surface modification using heptafluorobutyric acid to produce highly stable Li metal anodes

Nat Commun. 2023 May 19;14(1):2883. doi: 10.1038/s41467-023-38724-x.

Authors

Yuxiang Xie¹, Yixin Huang¹, Yinggan Zhang², Tairui Wu¹, Shishi Liu¹, Miaolan Sun¹, Bruce Lee³, Zhen Lin³, Hui Chen¹, Peng Dai¹, Zheng Huang¹, Jian Yang¹, Chenguang Shi¹, Deyin Wu¹, Ling Huang⁴, Yingjie Hua⁵, Chongtai Wang⁶, Shigang Sun⁷

Affiliations

¹ College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, 361005, Xiamen, China.
² College of Materials, Xiamen University, Xiamen Key Laboratory of Electronic Ceramic Materials and Devices, 361005, Xiamen, China.
³ Reliability Safety Department & Mechanism Simulation, Contemporary Amperex Technology Co., Limited., 352100, Ningde, China.
⁴ College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, 361005, Xiamen, China. huangl@xmu.edu.cn.
⁵ Hainan Normal University, Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province, 571158, Haikou, China.
⁶ Hainan Normal University, Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province, 571158, Haikou, China. wangct@hainnu.edu.cn.
⁷ College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, 361005, Xiamen, China. sgsun@xmu.edu.cn.

Abstract

The Li metal is an ideal anode material owing to its high theoretical specific capacity and low electrode potential. However, its high reactivity and dendritic growth in carbonate-based electrolytes limit its application. To address these issues, we propose a novel surface modification technique using heptafluorobutyric acid. In-situ spontaneous reaction between Li and the organic acid generates a lithiophilic interface of lithium heptafluorobutyrate for dendrite-free uniform Li deposition, which significantly improves the cycle stability (Li/Li symmetric cells >1200 h at 1.0 mA cm^-2) and Coulombic efficiency (>99.3%) in conventional carbonate-based electrolytes. This lithiophilic interface also enables full batteries to achieve 83.2% capacity retention over 300 cycles under realistic testing condition. Lithium heptafluorobutyrate interface acts as an electrical bridge for uniform lithium-ion flux between Li anode and plating Li, which minimizes the occurrence of tortuous lithium dendrites and lowers interface impedance.