State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems , China Electric Power Research Institute , Beijing 100192 , China.
China Electric Power Research Institute , Beijing 100192 , China.
ACS Appl Mater Interfaces. 2019 Mar 27;11(12):12154-12160. doi: 10.1021/acsami.9b01417. Epub 2019 Mar 13.
The high-viscosity issue of ionic liquids hinders the practical use of ionic liquid electrolytes for high-energy density batteries. Here, we demonstrate a novel heteroatom Si substituent imidazolium-based ionic liquid electrolyte, which has low viscosity and high ionic conductivity, and the heteroatom Si substituent weakens the activity of the C-2 position of imidazolium cation, prevents the formation of a highly loose lithium corrosion layer, and enables Li/LiFePO cycling with high coulombic efficiency (up to 99.7%) and greatly enhanced cycling stability. The electrolyte is intrinsically safe and stable with lithium metal, boosts the security of Li-metal usage, and enables dense-packing Li deposition of Li anode. This strategy of building heteroatom Si substituent ionic liquid is successful in reducing the viscosity, realizing safe and stable electrolyte for assembling a high-energy density battery.
离子液体的高粘度问题阻碍了其在高能密度电池中作为离子液体电解质的实际应用。在这里，我们展示了一种新型杂原子 Si 取代基咪唑鎓基离子液体电解质，其具有低粘度和高离子电导率，并且杂原子 Si 取代基削弱了咪唑鎓阳离子 C-2 位置的活性，防止了高度疏松的锂腐蚀层的形成，使 Li/LiFePO4 循环具有高库仑效率（高达 99.7%）和大大增强的循环稳定性。该电解质与金属锂具有本质上的安全性和稳定性，提高了锂金属使用的安全性，并实现了 Li 阳极的致密 Li 沉积。构建杂原子 Si 取代基离子液体的这种策略成功地降低了粘度，为组装高能量密度电池实现了安全稳定的电解质。
