Study of Fluoroethylene Carbonate (FEC) and Methylene Methanedisulfonate (MMDS) as Electrolyte Additives

锂离子电池是近年来电化学能源领域的研究热点，锂离子电池电解液提供锂离子穿梭于正负极之间，是锂离子电池获得高电压、高比能量以及高比功率的重要前提条件，也对电池的其他性能（如高低温及其安全性能）等起着关键作用，因此研发功能电解液是开发高性能锂离子电池时需要考虑的重要课题。功能电解液主要包括基础电解液（基础溶剂及其电解质）与添加剂两种组分，添加剂由于其只要在基础电解液中进行少量的添加就能做为功能电解液进而有效改善锂离子电池电化学性能，且不需要改变锂离子电池的结构和工艺的特点，成为功能电解液研究的热点之一。 本论文选择了两种电解液添加剂氟代碳酸乙烯酯（FEC）和甲基二磺酸亚甲酯（MMDS）来分别研究...Lithium ion batteries have been a top topic of green energy recent years. Electrolyte is an essential element to transport lithium ions between anode and cathode so that batteries can get high voltage, high energy density and high power, it also involves in improvements of other performances as high-low temperature and safety. These characteristics make electrolyte a best way to develop lithium io...学位：工程硕士院系专业：化学化工学院_工程硕士(化学工程)学号：X201119200

Effects of Fluoroethylene Carbonate Additive on Low Temperature Performance of Li-ion Batteries

本文通过磷酸铁锂/碳电池研究了电解液添加剂氟代乙烯碳酸酯（FEC）对电池低温性能的影响. 电池充放电实验证明，FEC添加剂能够在负极表面形成良好的固体电解质界面层（SEI）. 电解液中添加5% FEC后，电池-40 oC低温放电容量保持率可以从31.7%提高至43.7%，还提高了电池放电电压平台. 交流阻抗测试表明，FEC的加入能够有效降低电池的界面传荷阻抗（Rct）. 参比电极测试表明，其主要是降低了碳负极的低温极化.The effects of fluoroethylene carbonate (FEC) on the low temperature performance of lithium ion phosphate full battery are evaluated by different techniques. By addition of 5 wt% FEC into a commercial electrolyte, effective solid electrolyte interface (SEI) film can be formed on the graphite electrodes, the discharge capacity retention at -40 oC was increased from 31.7% to 43.7%, and the discharge voltage plateau of the cell is raised. This is attributed to a reduced charge transfer resistance and a lowered polarization on the graphite electrode by electrochemical impedance spectroscopy (EIS) and reference electrode test.福建省重大科技专项（No. 2009HZ0004）资助作者联系地址：1. 厦门大学电化学技术教育部工程研究中心，福建 厦门 361100；2. 厦门大学化学化工学院，福建 厦门 361005；3. 厦门大学能源研究院，福建 厦门 361100Author's Address: 1. Engineering Research Center of Electrochemical Technology of MOE, Xiamen, 361100; 2. College of Chemistry and Chemical Engineering, Xiamen, 361005; 3. School of Energy Research, Xiamen University, Xiamen, 361100通讯作者E-mail：[email protected]