A nitrile solvent structure induced stable solid electrolyte interphase for wide-temperature lithium-ion batteries

• DOI: 10.1039/d4sc03890h
• Publication Date: 2024-07-29T06:01:44Z
• Authors: Zhongming Wang; Zhiyuan He; Zhongsheng Wang; Jixu Yang; Kecheng Long; Zhibin Wu; Gang Zhou; Lin Mei; Libao Chen
• Keywords: Interphase

Lithium-ion batteries (LIBs) are extensively employed in various fields. Nonetheless, LIBs utilizing ethylene carbonate (EC)-based electrolytes incur capacity degradation a wide-temperature range, which is attributable to the slow Li+ transfer kinetics at low temperatures and solvent decomposition during high-rate cycling high temperatures. Here, we designed novel electrolyte by substituting nitrile solvents for EC, characterized de-solvation energy ionic conductivity. The correlation between carbon chain length of with reduction stability Li+-solvated coordination was investigated. results revealed that valeronitrile (VN) displayed an enhanced lowest unoccupied molecular orbital level energy, helped construct robust SEI interfacial layers improved ion LIBs. VN-based graphite‖NCM523 pouch cells achieved discharge 89.84% 20C rate room temperature. Meanwhile, cell exhibited 3C even temperature 55 °C. Notably, conductivity 1.585 mS cm-1 -50 retained 75.52% 65.12% their -40 °C °C, respectively. Wide-temperature-range have potential be applied extreme environments.