Lithium-ion battery electrolyte, lithium-ion battery and electronic instrument

• Main Authors: ZOU XIAOTIAN, HUANG BAONING, LUO BINGCAI
• Format: Patent
• Language: Chinese; English
• Published: 26.10.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention provides a lithium-ion battery electrolyte, comprising a solvent and an additive, wherein the solvent comprises propyl propionate and two or three selected from a group consisting of vinyl carbonate, diethyl carbonate and propylene carbonate, and the additive comprises vinyl sulfate, fluoroethylene carbonate, adiponitrile, glycol bis(propionitrile) ether, 1,3-propanesultone and fluorobenzene. A lithium-ion battery prepared from the lithium-ion battery electrolyte has stable usability under the condition of 4.40 V or 4.45 V, has energy density of 750 Wh/L or above, cycle life of 800 times or above and a capacity retention ratio of 80% or above, so the service life of a novel high-voltage high-energy-density polymer lithium-ion battery is substantially improved. 本发明提供了种锂离子电池电解液，包括：溶剂和添加剂；所述溶剂包括：丙酸丙酯；以及碳酸乙烯酯、碳酸二乙酯和碳酸丙烯酯中的任意两种或三种；所述添加剂包括：硫酸乙烯酯、氟代碳酸乙烯酯、己二腈、乙二醇(双丙腈)醚、1,3-丙基磺酸内酯和氟苯。本发明通过采用上述特定组分的电解液，制备的锂离子电池，在4.40V或4.45V下使用性能稳定，且能量密度能够达到750Wh/L以上，循环寿命可以达到800次以上，容量保持率大于80％，显著提高了新代高电压及高能量密度聚合物锂离子电池的使用寿命。