Energy and Environmental Directorate, Pacific Northwest National Laboratory , 902 Battelle Boulevard, Richland, Washington 99354, United States.
Environmental and Molecular Sciences Laboratory, Pacific Northwest National Laboratory , 3335 Innovation Boulevard, Richland, Washington 99354, United States.
ACS Appl Mater Interfaces. 2017 Dec 13;9(49):42761-42768. doi: 10.1021/acsami.7b13887. Epub 2017 Nov 28.
Lithium (Li) ion battery has penetrated almost every aspect of human life, from portable electronics, vehicles, to grids, and its operation stability in extreme environments is becoming increasingly important. Among these, subzero temperature presents a kinetic challenge to the electrochemical reactions required to deliver the stored energy. In this work, we attempted to identify the rate-determining process for Li migration under such low temperatures, so that an optimum electrolyte formulation could be designed to maximize the energy output. Substantial increase in the available capacities from graphite∥LiNiCoAlO chemistry down to -40 °C is achieved by reducing the solvent molecule that more tightly binds to Li and thus constitutes a high desolvation energy barrier. The fundamental understanding is applicable universally to a wide spectrum of electrochemical devices that have to operate in similar environments.
锂离子电池已经渗透到人类生活的方方面面，从便携式电子产品、车辆到电网，其在极端环境下的运行稳定性变得越来越重要。在这些环境中，低温对储存能量所需的电化学反应带来了动力学挑战。在这项工作中，我们试图确定在这种低温下 Li 迁移的速率决定过程，以便设计出最佳的电解质配方，从而最大限度地提高能量输出。通过减少与 Li 结合更紧密的溶剂分子，从而降低高去溶剂化能垒，石墨//LiNiCoAlO 化学物质的可用容量从 -40°C 显著增加。这一基本认识普遍适用于在类似环境中运行的各种电化学器件。
