黄蓍胶在硅负极锂离子电池中的应用
和帅帅,刘 健*,龚正良,甘礼惠,龙敏南

(厦门大学能源学院,福建 厦门 361102)

锂离子电池; 硅纳米颗粒; 黄蓍胶; 水系黏结剂; 电化学性能

Application of tragacanth gum in silicon anode lithium-ion battery
HE Shuaishuai,LIU Jian*,GONG Zhengliang,GAN Lihui,LONG Minnan

(College of Energy,Xiamen University,Xiamen 361102,China)

DOI: 10.6043/j.issn.0438-0479.202002028

备注

黏结剂在硅基锂离子电池中的用量虽少,但它却是电池性能的重要影响因素之一.使用水溶性聚合物黄蓍胶作为一种新型的硅基锂离子电池黏结剂,并与较为常见的黏结剂羧甲基纤维素钠(CMC)制备的锂离子电池在循环性能、倍率性能、循环伏安特性以及电化学阻抗方面进行比较与分析,利用扫描电镜(SEM)对锂离子电池循环前后的极片材料进行表征.实验结果显示:采用CMC和黄蓍胶作为硅基锂离子电池黏结剂时,首圈在210 mA/g的电流密度下,放电比容量分别为2 808.7和3 178.7 mAh/g,首次库伦效率分别为68.84%和83.64%; 此后在420 mA/g的电流密度下,循环100圈后的放电比容量分别为485.7和1 360.1 mAh/g,甚至经过200圈的长期循环后,使用黄蓍胶作为黏结剂的电池放电比容量仍达到1 056.0 mAh/g.实验证明黄蓍胶有望成为一种新型且性能优异的水溶性硅负极锂离子电池黏结剂.
Binder used in silicon-based lithium-ion batteries,although its amount is small,is one of the important factors affecting the battery performance.In this study,water-soluble polymer tragacanth gum was used as a new type of binder for silicon-based lithium-ion batteries,and compared with common binder carboxymethyl cellulose(CMC)in terms of cycle performance,rate performance,cyclic voltammetry characteristics and electrochemical inpedance,and scanning electron microscopy(SEM)was applied to characterize the materials of the anodes before and after cycling of the lithium-ion batteries.The experimental results showed that when CMC and tragacanth gum were used as binders,for silicon-based lithium-ion batteries at a current density of 210 mA/g,the first discharge specific capacity were 2 808.7 and 3 178.7 mAh/g,respectively,and the first coulombic efficiency were 68.84% and 83.64%,respectively.After cycling for 100 cycles at the current density of 420 mA/g,their discharge specific capacity were 485.7 and 1 360.1 mAh/g,respectively,and even the battery with tragacanth gum as binder remained at 1 056.0 mAh/g after a long cycling of 200 cycles.It has been proved that the tragacanth gum is expected to become a new type of water-soluble binder for silicon negative electrode lithium-ion battery.