储能科学与技术 ›› 2018, Vol. 7 ›› Issue (2): 240-247.doi: 10.12028/j.issn.2095-4239.2017.0164

• 研究开发 • 上一篇    下一篇

基于LiFePO4和活性炭的混合型电化学储能器件研究

张世明1,2，车海英1，杨  柯1，杨馨蓉1，郑  丹2，马紫峰1,2   

  1. 1上海交通大学化学工程系，上海电化学能源器件工程技术中心，上海 200240；2上海中聚佳华电池科技有限公司，中聚电池研究院，上海 200241
  • 收稿日期:2017-11-20 修回日期:2018-01-25 出版日期:2018-03-01 发布日期:2018-03-01
  • 通讯作者: 张世明（1986—），男，博士，从事锂离子电池、超级电容器、燃料电池等电化学能源器件及材料研究，E-mail：zhangsm860409@sjtu.edu.cn
  • 基金资助:
    国家基础研究项目（2014CB239703），国家自然科学基金项目（21606149，21336003），中国博士后基金项目（2016M591678）和上海市青年科技启明星计划（B类）（18QB1404400）。

Development of hybrid electrochemical energy storage device based on LiFePO4 and activated carbon

ZHANG Shiming1,2, CHE Haiying1, YANG Ke1, YANG Xinrong1, ZHENG Dan2, MA Zifeng1,2   

  1. 1Department of Chemical Engineering, Shanghai Electrochemical Energy Device Research Center, Shanghai Jiao Tong University, Shanghai 200240, China; 2 Shanghai Sinopoly Jiahua Battery Technology Co., Ltd., Sinopoly Battery Research Center, Shanghai 200241, China
  • Received:2017-11-20 Revised:2018-01-25 Online:2018-03-01 Published:2018-03-01

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摘要： 基于磷酸铁锂（LiFePO4）和活性炭（AC）两种单体材料成功构建了磷酸铁锂/活性炭（LiFePO4/AC）复合正极。进一步，通过优化LiFePO4/AC复合电极中两种单体材料的质量比、选择亚微米尺寸的石墨为负极材料, 组装了基于“LiFePO4+AC/石墨”体系的电化学储能器件（锂离子电容器），同时制备了AC/AC超级电容器作为参照。研究表明，不同类型黏结剂对AC电极的电容特性影响非常显著，其中LA133水性黏结剂的电极性能优于油性黏结剂的；此外，制备的LiFePO4/AC复合正极表现出了电容和电池的双重特性，且复合电极的构建有利于锂离子的嵌入和脱出。复合正极中LiFePO4含量为40%（质量分数）时，构建的锂离子电容器比能量为AC/AC超级电容器的4倍（约40 W·h/kg，以活性材料质量计），可实现10 C快速充放电；5000次循环后，锂离子电容器和AC/AC超级电容器容量保持率相近，约为初始容量的75%。

关键词: 锂离子电容器, 亚微米石墨, LiFePO4/AC复合正极, 水性黏结剂, 快充, 长寿命

Abstract:

 Mixed bi-material composite electrode based on LiFePO4 and activated carbon (AC) for hybrid electrochemical energy storage (EES) devices was prepared. The EES devices have been constructed by choosing submicron graphite as anode material and optimizing LiFePO4/AC composites with different mass ratios as the cathode. The results showed that binders had great influence on the capacitive properties of AC, and LA133 as one of the water-based binders should be better choice than oily adhesives. Furthermore, the prepared LiFePO4/AC composite cathodes emerged the dual characteristics of capacitor and battery. As the 40% (weight ratio) of LiFePO4 in the composite cathode, the lithium-ion capacitor could reveal high specific energy which is about 4 times comparing with that of AC/AC supercapacitor (about 40 W·h·kg-1) by computation of the total active materials. Also, it could achieve the fast charge-discharge at 10 C rate. In addition, both of the two devices exhibited the similar cyclability with about 75% of capacity retention after about 5000 cycles.

Key words: lithium-ion capacitor, submicron graphite, LiFePO4/AC composite cathode, water-based binder, fast-charging, long-life