Dual-Anionic Coordination Manipulation Induces Phosphorus and Boron-Rich Gradient Interphase Towards Stable and Safe Sodium Metal Batteries

作     者：Yi-Hu Feng Dr. Mengting Liu Wenli Qi Haoliang Liu Qiang Liu Dr. Chao Yang Yongwei Tang Xu Zhu Shuai Sun Yuan-Meng Li Tian-Ling Chen Bing Xiao Prof. Xiao Ji Prof. Ya You Prof. Peng-Fei Wang 

作者机构：Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an Shaanxi 710049 P. R. China School of Optical and Electronic Information-Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan Hubei 430074 P. R. China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan Hubei 430070 P. R. China Jiangsu Jufeng New Energy Technology Co. Ltd. Changzhou Jiangsu 213166 P. R. China 

出 版 物：《Angewandte Chemie》 

年 卷 期：2024年第137卷第3期

学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 

主　　题：sodium metal batteries electrolyte non-flammable cathode/electrolyte interphase solvation structure 

摘      要：High-voltage sodium metal batteries (SMBs) present a viable pathway towards high-energy-density sodium-based batteries due to the competitive cost advantage and abundant supply of sodium resources. However, they still suffer from severe capacity decay induced by the notorious decomposition of the electrolyte under high voltage and unstable cathode/electrolyte interphase (CEI). In addition, the high reactivity of Na metal and flammable electrolytes push SMBs to their safety limits. Herein, a special dual-anion aggregated Na + solvation structure is designed in a nonflammable trimethyl phosphate-based localized high-concentration electrolyte, and a gradient CEI enriched with phosphorus and boron compounds is formed on the cathode. This thin and stable interphase effectively suppresses the parasitic reaction, improves the interfacial stability of the cathode, and facilitates Na + transport through the interface by the synergistic effect of multi-components, thus optimizing the cycling stability and safety of SMBs. The Na 0.95 Ni 0.4 Fe 0.15 Mn 0.3 Ti 0.15 O 2 //Na batteries employing such electrolyte provide a discharge capacity of 167.5 mAh g −1 and high retention in the capacity of 85.2 % after 800 cycles at 1 C. This approach offers a general strategy for the design of flame-retardant high-voltage electrolytes and the practical application of SMBs.