本文综述了适合高温锂离子电池用电解液的研究进展和发展前景。从电解质盐和溶剂的高温稳定性方面进行了论述,阐明了现有商用电解液体系在高温时的不足,提出了开发高温电解质盐、难燃有机溶剂、离子液体和阻燃添加剂的思路。通过官能团的修饰,可以克服现有锂盐的不足,开发出适用于高温条件的电解质盐。非碳酸酯类有机溶剂单独使用时的电化学性能较差,离子液体与常用正负极材料的兼容性有待改善,目前最有可能实用化的高温电解液是碳酸酯和阻燃剂的共混体系。通过引入多种阻燃元素或部分基团改进,可以合成出综合性能良好的阻燃剂,进而提高电解液的高温适用性。
Research progress and prospects of electrolytes used at elevated-temperature for lithium-ion batteries are summarized in this paper. The deficiency of current commercial electrolytes at high temperature is clarified according to the chemical stability of solutes and solvents. Some ideas are proposed to develop the thermal stability of lithium salts, ionic liquids and flame retardant additives. The deficiencies of the present lithium salts can be overcome through the modification of functional group or the structure composite, and new kind of lithium salt can be developed for elevated-temperature lithium ion battery. Non-carbonic acid ester showed poor performance when it was used alone, ionic liquids showed poor compatibility with commonly used anode and cathode materials. The most possible way for the application of high-temperature electrolyte is the blend of carbonates and flame retardants. Better flame retardant can be achieved by introducing flame-retardant elements into phosphate ester or modifying part of the functional group, which will improve the performance of electrolyte in high temperature.