Nonflammable Sulfone-Based Electrolytes with Mechanically and Thermally Stable Interfaces Enabling LiNi 0.5 Mn 1.5 O 4 to Operate at High Temperature

作者：Tianling Chen, Mengting Liu, Xin-Yu Fan, Yi‐Hu Feng, Qiang Liu, Xue‐Ru Liu, Hanshen Xin, Pengfei Wang · 发表于：ACS Energy Letters · 年份：2024 · DOI：10.1021/acsenergylett.4c02458 · 被引用次数：58 · 研究领域：Advanced Battery Materials and Technologies、Advanced battery technologies research、Thermal Expansion and Ionic Conductivity

The development of high-energy 5 V-class LiNi 0.5 Mn 1.5 O 4 batteries is severely limited by the instability of the cathode electrolyte interphase (CEI) at high temperature. Herein, we propose a nonflammable sulfone (SL)-based fluorinated hybrid electrolyte to form stable, uniform, and thin CEI layers, enabling Li||LiNi 0.5 Mn 1.5 O 4 batteries to achieve elevated electrochemical performance at 60 °C. The formed highly stable inorganic-dominated CEI, comprising Li x SO y, Li x BO y, and LiF inorganic compositions, exhibits good thermal stability and mechanical strength. Moreover, the robust CEI layer effectively shields the LNMO particles from undesirable side-reactions and stabilizes the interface within the LiNi 0.5 Mn 1.5 O 4 cathode during high-temperature cycling. In contrast to the conventional electrolyte, the Li||LiNi 0.5 Mn 1.5 O 4 battery employing a nonflammable SL-based electrolyte exhibits a stable capacity retention of 88.5% after 100 cycles at 60 °C free from the risk of thermal runaway. This study reveals valuable insights into advanced electrolyte technology, paving the way for safer applications of Co-free high-energy batteries in the future.