Ethylene Carbonate Regulated Solvation of Triethyl Phosphate to Enable High-Conductivity, Nonflammable, and Graphite Compatible Electrolyte

作者：Mengchuang Liu, Ziqi Zeng, Chenkai Gu, Fenfen Ma, Yuanke Wu, Qiang Wu, Xiankun Yang, Xin Chen, Shijie Cheng, Jia Xie · 发表于：ACS Energy Letters · 年份：2023 · DOI：10.1021/acsenergylett.3c02414 · 被引用次数：62 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Advanced Battery Technologies Research

In the landscape of lithium-ion batteries (LIBs), carbonate-based electrolytes have driven remarkable progress, but persistent safety concerns stemming from their flammability necessitate innovative solutions. This study explores a cost-effective nonflammable cosolvent, triethyl phosphate (TEP), to counter the risk. However, TEP’s strong Li + -coordinating propensity adversely affects graphite (Gr) electrode intercalation. To surmount these challenges, we unveil the competitive coordination behavior of TEP and ethylene carbonate, strategically optimizing TEP’s coordination numbers. This tailored approach culminates in a dynamically stable structure which reduces the adverse effects of TEP. Leveraging these insights, we engineer a TEP-modified carbonate electrolyte with standard Li salt concentration (1 M) boasting both nonflammability and high ionic conductivity, enabling the Gr anode to achieve ∼100% capacity retention after 150 cycles. Additionally, this formulation significantly minimizes fire and explosion risks in 4 A h Gr||LiNi 0.9 Co 0.05 Mn 0.05 O 2 pouch cells during mechanical stress, demonstrating profound implications for safer energy storage in LIBs.