School of Materials Science and Engineering, Tianjin University , Tianjin 300072, P. R. China.
Tianjin Key Laboratory of Composite and Functional Materials , Tianjin 300072, P. R. China.
ACS Appl Mater Interfaces. 2018 Feb 28;10(8):7171-7179. doi: 10.1021/acsami.7b19726. Epub 2018 Feb 15.
A major stumbling block in large-scale adoption of high-energy-density electrochemical devices has been safety issues. Methods to control thermal runaway are limited by providing a one-time thermal protection. Herein, we developed a simple and reversible thermoresponsive electrolyte system that is efficient to shutdown the current flow according to temperature changes. The thermal management is ascribed to the thermally activated sol-gel transition of methyl cellulose solution, associated with the concentration of ions that can move between isolated chains freely or be restricted by entangled molecular chains. We studied the effect of cellulose concentration, substituent types, and operating temperature on the electrochemical performance, demonstrating an obvious capacity loss up to 90% approximately of its initial value. Moreover, this is a cost-effective approach that has the potential for use in practical electrochemical storage devices.
在大规模采用高能量密度电化学器件方面，一个主要的障碍一直是安全问题。控制热失控的方法受到限制，因为这些方法只能提供一次性的热保护。在这里，我们开发了一种简单且可重复使用的热敏电解质体系，能够根据温度变化有效地切断电流。这种热管理归因于甲基纤维素溶液的热激活溶胶-凝胶转变，与能够在孤立链之间自由移动或被缠结分子链限制的离子浓度有关。我们研究了纤维素浓度、取代基类型和工作温度对电化学性能的影响，结果表明，其初始值约有明显的 90%的容量损失。此外，这是一种具有成本效益的方法，有可能用于实际的电化学储能设备。
