Restructuring Electrolyte Solvation by a Versatile Diluent Toward Beyond 99.9% Coulombic Efficiency of Sodium Plating/Stripping at Ultralow Temperatures

Hu，Liang1; Deng，Jiaojiao2; Lin，Yuxiao3; Liang，Qinghua4; Ge，Bingcheng1; Weng，Qingsong1; Bai，Yu5; Li，Yunsong6; Deng，Yonghong7; Chen，Guohua8; Yu，Xiaoliang1

2024

10.1002/adma.202312161

Advanced Materials   影响因子和分区

0935-9648

1521-4095

The reversible and durable operation of sodium metal batteries at low temperatures (LT) is essential for cold-climate applications but is plagued by dendritic Na plating and unstable solid-electrolyte interphase (SEI). Current Coulombic efficiencies of sodium plating/stripping at LT fall far below 99.9%, representing a significant performance gap yet to be filled. Here, the solvation structure of the conventional 1 m NaPF in diglyme electrolyte by facile cyclic ether (1,3-dioxolane, DOL) dilution is efficiently reconfigured. DOL diluents help shield the Na-PF Coulombic interaction and intermolecular forces of diglyme, leading to anomalously high Na-ion conductivity. Besides, DOL participates in the solvation sheath and weakens the chelation of Na by diglyme for facilitated desolvation. More importantly, it promotes concentrated electron cloud distribution around PF in the solvates and promotes their preferential decomposition. A desired inorganic-rich SEI is generated with compositional uniformity, high ionic conductivity, and high Young's modulus. Consequently, a record-high Coulombic efficiency over 99.9% is achieved at an ultralow temperature of −55 °C, and a 1 Ah capacity pouch cell of initial anode-free sodium metal battery retains 95% of the first discharge capacity over 100 cycles at −25 °C. This study thus provides new insights for formulating electrolytes toward increased Na reversibility at LT.

diluent electrolyte solvation low temperature Na plating/stripping reversibility sodium metal battery

SCI ; EI

英语

其他

MATERIALS SCIENCE

2-s2.0-85182232212

Scopus

1.Department of Mechanical Engineering and Research Institute for Smart Energy,The Hong Kong Polytechnic University,Hong Kong
2.Graphene Composite Research Center,College of Chemistry and Environmental Engineering,Shenzhen University,Shenzhen,518060,China
3.School of Physics and Electronic Engineering,Jiangsu Normal University,Xuzhou,Jiangsu Province,221116,China
4.Key Laboratory of Rare Earth,Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou,Jiangxi,341000,China
5.Shenzhen XFH Science and Technology Co.,Ltd.,Shenzhen,518071,China
6.Zhejiang Laboratory,Hangzhou,311100,China
7.Department of Materials Science and Engineering,Guangdong Provincial Key Laboratory of Energy Materials for Electric Power,Southern University of Science and Technology (SUSTech),Shenzhen,518055,China
8.School of Energy and Environment,City University of Hong Kong,Kowloon,Hong Kong

Hu，Liang,Deng，Jiaojiao,Lin，Yuxiao,et al. Restructuring Electrolyte Solvation by a Versatile Diluent Toward Beyond 99.9% Coulombic Efficiency of Sodium Plating/Stripping at Ultralow Temperatures[J]. Advanced Materials,2024.

Hu，Liang.,Deng，Jiaojiao.,Lin，Yuxiao.,Liang，Qinghua.,Ge，Bingcheng.,...&Yu，Xiaoliang.(2024).Restructuring Electrolyte Solvation by a Versatile Diluent Toward Beyond 99.9% Coulombic Efficiency of Sodium Plating/Stripping at Ultralow Temperatures.Advanced Materials.

Hu，Liang,et al."Restructuring Electrolyte Solvation by a Versatile Diluent Toward Beyond 99.9% Coulombic Efficiency of Sodium Plating/Stripping at Ultralow Temperatures".Advanced Materials (2024).