McEldrew Michael, Goodwin Zachary A H, Kornyshev Alexei A, Bazant Martin Z
Department of Chemical Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts , United States.
Department of Physics, CDT Theory and Simulation of Materials , Imperial College of London, South Kensington Campus , London SW7 2AZ , U.K.
J Phys Chem Lett. 2018 Oct 4;9(19):5840-5846. doi: 10.1021/acs.jpclett.8b02543. Epub 2018 Sep 25.
One challenge in developing the next generation of lithium-ion batteries is the replacement of organic electrolytes, which are flammable and most often contain toxic and thermally unstable lithium salts, with safer, environmentally friendly alternatives. Recently developed water-in-salt electrolytes (WiSEs), which are nonflammable, nontoxic, and also have enhanced electrochemical stability, are promising alternatives. In this work, we develop a simple modified Poisson-Fermi theory for WiSEs, which demonstrates the fine interplay between electrosorption, solvation, and ion correlations. The phenomenological parameters are extracted from molecular dynamics simulations, also performed here. The theory reproduces the WiSEs' electrical double-layer structure with remarkable accuracy.
开发下一代锂离子电池面临的一个挑战是用更安全、环保的替代品取代有机电解质，有机电解质易燃，且大多含有有毒且热不稳定的锂盐。最近开发的盐包水电解质（WiSEs）不可燃、无毒，且具有增强的电化学稳定性，是很有前景的替代品。在这项工作中，我们为WiSEs开发了一种简单的修正泊松-费米理论，该理论展示了电吸附、溶剂化和离子相关性之间的良好相互作用。唯象参数是从这里也进行的分子动力学模拟中提取的。该理论以极高的精度再现了WiSEs的双电层结构。
