Increased Stability Toward Oxygen Reduction Products for Lithium-Air Batteries with Oligoether-Functionalized Silane Electrolytes
Increased Stability Toward Oxygen Reduction Products for Lithium-Air Batteries with Oligoether-Functionalized Silane Electrolytes
复制标题
DOI：
10.1021/jp2087412
复制
发表时间：
2011-12-29
影响因子：
3.7
通讯作者：
Amine, Khalil
中科院分区：
文献类型：
--
作者：
Zhang, Zhengcheng;Lu, Jun;Amine, Khalil
锂空气电池的成功开发将大大增加电动汽车续航里程的可能性。有很多证据表明，锂离子电池中使用的典型的有机碳酸酯基电解质在锂-空气电池中放电期间与氧还原产物反应形成碳酸锂，因此需要找到更稳定的电解质。（乙二醇）取代的三甲基硅烷（1 NM 3）提供了醚对氧还原放电物质更稳定的证据。X射线光电子能谱（XPS）和红外光谱（FTIR）分析表明，在1 NM 3电解液中，锂离子电池只生成锂氧化物，没有生成碳酸盐。相比之下，XPS显示在相同电池配置中的碳酸丙烯酯（PC）在放电期间分解形成碳酸锂。涉及溶剂化氧还原物种的可能的分解反应途径的密度泛函计算证实，低聚醚取代的硅烷，以及其他醚，比碳酸丙烯酯的氧还原产物更稳定。这些结果表明，电解质的选择对锂空气电池的性能起着关键作用。
The successful development of Li-air batteries would significantly increase the possibility of extending the range of electric vehicles. There is much evidence that typical organic carbonate based electrolytes used in lithium ion batteries form lithium carbonates from reaction with oxygen reduction products during discharge in lithium-air cells so more stable electrolytes need to be found. This combined experimental and computational study of an electrolyte based on a tri(ethylene glycol)-substituted trimethylsilane (1NM3) provides evidence that the ethers are more stable toward oxygen reduction discharge species. X-ray photoelectron spectroscopy (XPS) and FTIR experiments show that only lithium oxides and no carbonates are formed when 1NM3 electrolyte is used. In contrast XPS shows that propylene carbonate (PC) in the same cell configuration decomposes to form lithium carbonates during discharge. Density functional calculations of probable decomposition reaction pathways involving solvated oxygen reduction species confirm that oligoether substituted silanes, as well as other ethers, are more stable to the oxygen reduction products than propylene carbonate. These results indicate that the choice of electrolyte plays a key role in the performance of Li-air batteries.