Improving Na_(3)V_(2)(PO_(4))_(2)F_(3)half-cell performance with NaBF_(4)-enhanced sodium difluoro(oxalato)borate electrolyte  

作　　者：Jia Zhang Jianwei Li Guofeng Jia Huaiyou Wang Min Wang 

机构地区：[1]Key Laboratory of Green and High-end Utilization of Salt Lake Resources,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining 810008,Qinghai,China [2]Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt Lakes,Xining 810008,Qinghai,China [3]Universityof Chinese Academy of Sciences,Beijing 101408,China

出　　处：《Journal of Energy Chemistry》2025年第3期340-352,共13页能源化学(英文版)

基　　金：financially supported by the Cultivation and Construction of Ten National Science and Technology Innovation Platforms in Qinghai Province(2024-ZJ-J03);Xining Major Science and Technology Innovation Platform Capacity Building Project(2024-Z1);funding from Young Scholars of Western China,Chinese Academy of Sciences(E110HX0501);Qinghai Province Youth Science and Technology Talent Support Project(2022QHSKXRCTJ06)。

摘　　要：The global shift towards low-carbon energy storage has increased interest in sodium-ion batteries(SIBs)as a safer,cost-effective alternative to lithium-ion batteries.However,the commercial viability has been limited by compatibility issues between high-energy-density cathode materials,such as Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF),and high-voltage electrolytes.Addressing the challenges,H-NaODFB(comprising 93.91%NaODFB and 5.85%NaBF_(4))electrolyte significantly improves the electrochemical performance and stability of NVPF cathodes,Na/NVPF half-cells using H-NaODFB electrolyte retained 92.4%capacity after 900cycles,while Na/Na symmetric cells demonstrated a cycle life exceeding 600 h at 0.5 mA cm^(-2).The superior performance is attributed to improved Na^(+)(de)intercalation reversibility,lower interfacial impedance(619.8 vs.10,650.0Ω),and faster reaction kinetics compared to NaODFB alone.Advanced time of flight-secondary ion mass spectrometry(TOF-SIMS),X-ray photoelectron spectroscopy(XPS)and aberration corrected transmission electron microscope(AC-TEM),combined with first-principles calculations,revealed that NaBF_(4)in the H-NaODFB electrolyte plays a critical role in forming a stable cathode electrolyte interphase(CEI).The CEI consists of an initial inorganic and organic layer,followed by a fluoroborate layer,and finally a stable organic-inorganic polymeric layer,enhancing electrode stability and preventing over-oxidation.These findings provide valuable insights for designing high-performance electrolytes for SIBs.

关 键 词：Sodium-ion batteries NaODFB-based electrolyte Na_(3)V_(2)(PO_(4))_(2)F_(3) High-voltage Cathode electrolyte interphase 

分 类 号：TM912[电气工程—电力电子与电力传动]