Effect of Flame Retardant on Electrochemical Performances of Lithium Ion Battery with LiNi0.4Co0.2Mn0.4O2 as a Positive Electrode Material

测试了不同浓度的电解液阻燃添加剂对镍钴锰三元材料（LiNi0.4Co0.2Mn0.4O2）作为正极的锂离子电池电化学性能的影响. 实验结果表明，当阻燃剂浓度增加时，电池的放电容量下降，电化学反应电阻和锂离子扩散阻力都有所增加，但加入阻燃添加剂的锂离子电池，当充放电的电流相对比较小的时候，循环性能相比于不含阻燃剂的有所提高，循环稳定性得到了改善. 在0.5C倍率电流下，不含阻燃剂时容量保持率为89%，而当阻燃剂含量增至10%后保持率达到94.21%. 当充放电电流为1C时，未使用阻燃剂时容量保持率约为92.22%，当阻燃剂的浓度为10%时容量保持率为93.01%. 在2C倍率下，不含阻燃剂时容量保持率为87.92%. 阻燃剂浓度为10%时，容量保持率有所提升，达到92.16%. 与基础电解液相比，选用含有10%阻燃剂的电解液可使容量保持率提高5%左右，相比于其他浓度，包含10%阻燃剂的电池循环性能也最为稳定.The effect of flame retardant on the electrochemical performances of lithium ion battery by using LiNi0.4Co0.2Mn0.4O2 as a positive material was studied by measuring the first charge-discharge, cycling, circulation, and AC impedance curves. The experimental data indicated that the discharge capacity of the battery decreased, while the charge transfer resistance and the lithium ion diffusion resistance increased with the increases in the concentrations of the flame retardant in the electrolyte solutions. Furthermore, the stability of the battery at small discharge ratios and the cyclic performance were also improved by the addition of flame retardant. The capacitance retention values went up from 89% without the addition of flame retardant to 94.21% with the addition of 10% flame retardant at the discharge ratio of 0.5C, from 92.22% to 93.01% at 1C, and from 87.92% to 92.16% at 2C. The best cycle stability of the battery was achieved with the addition of 10% flame retardant.国家自然科学基金项目（No. 21203040）、中国博士后面上项目（No. 2014M561357）、浙江省博士后科研项目择优资助基金（No. zj140288）及黑龙江省自然科学基金项目(No. B201201)资助作者联系地址：1. 哈尔滨工业大学化工学院，黑龙江 哈尔滨 150001；2. 哈尔滨工程大学材料科学与化学工程学院 超轻材料与表面技术教育部重点实验室，黑龙江 哈尔滨 150001；3. 超威电源有限公司，浙江 长兴 313100Author's Address: 1. School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001, China; 2. Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China; 3. Chaowei Power Co., LTD, Changxing 313100, Zhejiang, China通讯作者E-mail：[email protected]

Electrochemical Behavior of Mg-Li Electrodes in NaCl Solution

应用熔炼法制备含Li量为8.5%和14%的两种Mg-Li合金,分别由电势线性扫描、计时电流、交流阻抗和失重法等检测Mg-Li电极在NaCl溶液中的电化学特性,SEM观察其放电表面形貌.结果表明:Mg-14Li电极比Mg-8.5Li电极有较负的开路电位、更大的放电电流和较高的放电效率,但附着电极表面的疏松产物易于脱落.Mg-8.5Li电极的放电效率高于Mg-14Li电极的放电效率.两种电极在低恒电位放电电流效率均高于较高恒电位的放电电流效率.The Mg-Li electrodes containing 8.5% and 14% Li were prepared using an induction melting method.Their electrochemical behavior in NaCl solution was investigated by means of potentiodynamic polarization,potentiostatic oxidation,electrochemical impedance technique and mass-loss measurements.The morphology of the electrodes after discharge was examined using scanning electron microscopy.The Mg-14Li electrode showed more negative open circuit potential and higher discharge current density than Mg-8.5Li electrode.The oxidation products of Mg-14Li loosely attached on the electrode surface and peeled off easily.The Mg-8.5Li exhibited higher utilization efficiency.Both electrodes gave higher utilization efficiencies when discharged at lower anodic potential.作者联系地址：哈尔滨工程大学超轻材料与表面技术教育部重点实验室材料科学与化学工程学院;Author's Address: Key Laboratory of Superlight Material and Surface Technology of Ministry of Education,College of Material Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,Chin

Effects of Flame Retardant on the Rate Capability and Safety Performances of the Soft-Package 5Ah Lithium Ion Battery

在电解液中加入不同含量(5 %，10 %，20 %)的阻燃剂，研究了其对LiNi 0.4Co0.2Mn0.4 O2三元材料作为正极材料组装的5 Ah锂离子软包电池的倍率性能、过充性能和短路性能的影响. 实验结果表明，电解液中5 %体积含量的阻燃剂使软包电池在1C和2C放电时，具有最好的倍率性能；当阻燃剂的体积含量提升到20 %，在过充时，电池表面温度升高的最少；在短路实验时，电池不起火、不爆炸.The 5 Ah soft packed lithium ion batteries with LiNi 0.4Co0.2Mn0.4 O2 as the positive electrode material and the organic electrolytes with different amounts of fire retardants as the electrolyte solution were prepared. The effects of the fire retardant amount (5 %，10 %，20 %) of the fire retardants on the rate performances, short-circuit characteristics and overcharged behaviors of the 5 Ah soft packed lithium ion battery were investigated by electrochemical methods. The results indicated that the best rate performances were obtained by adding 5 vol.% of the fire retardants in the electrolyte solution when the battery was discharged at 1C and 2C. The battery had the lowest surface temperature with 20 vol.% of fire retardant in the electrolyte solution when it was over-charged. The batteries could not catch fire and explode when the battery were short-circuited.国家自然科学基金项目（No.21203040）、中国博士后面上项目（No.2014M561357）、浙江省博士后科研项目择优资助资金(No.zj140288)、黑龙江省自然科学基金项目(No. B201201)资助作者联系地址：1.哈尔滨工业大学化工学院，黑龙江 哈尔滨　150001；2.哈尔滨工程大学材料科学与化学工程学院，黑龙江 哈尔滨150001；3.超威电源有限公司 研究院，浙江长兴 313100Author's Address: 1. School of Chemical Engineering and Technology, Harbin Institute of Technology, No.92 West-Da Zhi Street, Harbin, 150001 China; 2. College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin, 150001 China; 3. Chaowei Power Co., LTD, Changxing, 313100 China通讯作者E-mail：[email protected]