储能科学与技术 ›› 2017, Vol. 6 ›› Issue (1): 116-121.doi: 10.12028/j.issn.2095-4239.2016.0027

• 研究开发 • 上一篇    下一篇

水性胶黏剂在磷酸铁锂电极制备过程中的应用研究

李山河1,2，廖小珍1，赵政威2，卢  诚2，叶  茂2，何  龙3，罗红斌3，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研究中心，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；3比亚迪汽车工业有限公司，广东 深圳 518118
  • 收稿日期:2016-06-12 修回日期:2016-08-09 出版日期:2017-01-03 发布日期:2017-01-03
  • 通讯作者: 马紫峰，教授，E-mail：zfma@sjtu.edu.cn。
  • 作者简介:李山河（1970—），男，高级工程师，硕士研究生，研究方向为锂离子电池制造工艺，E-mail：shli@sinopolybattery.com；
  • 基金资助:
    国家重点基础研究发展计划项目（973计划）（2014CB239703），国家自然科学基金（21336003，21573147）及上海市科委项目（14DZ2250800，15ZR1422300）。

Application of different aqueous binders in LiFePO4 electrode

LI Shanhe1,2, LIAO Xiaozhen1, ZHAO Zhengwei2, LU Cheng2, YE Mao2, HE Long3, LUO Hongbin3, MA Zifeng1,2   

  1. 1Department of chemical engineering, Shanghai Jiao Tong University, Shanghai Electrochemical Energy Device Engineering Technology Research Center, Shanghai 200240, China; 2Sinopoly Battery Research Institute, Shanghai 200241, China; 3BYD Automobile Company Limited, Shenzhen 518118, Guangdong, China
  • Received:2016-06-12 Revised:2016-08-09 Online:2017-01-03 Published:2017-01-03

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摘要： 锂离子电池电极中的胶黏剂是其不可或缺的重要组成部分且直接影响到电池性能。水性胶黏剂有生产环保、成本低等突出优势，成为近期研究热点。本文研究了水性胶黏剂在磷酸铁锂体系中的应用，通过CV测试表明，聚丙烯酸脂类胶黏剂具有较高的氧化电位（4.65 V），适宜用作正极的胶黏剂。通过热分析仪分析了两种聚丙烯酸酯类胶黏剂LA和LB的特性，实验结果表明，LB有相对较好的热稳定性（热分解温度325 ℃）。用LA、LB胶黏剂制成的磷酸铁锂电池，通过EIS测试了电极锂离子扩算系数分别为6.2×1014 cm2/s和1.8×1014 cm2/s。通过电性能测试分析了LA和LB胶黏剂对磷酸铁锂电池容量、内阻、倍率等电性能的影响。研究表明，当LA胶黏剂添加量为3%时，电池性能较佳；LB添加量为2.5%，极片压实为2.25 g/cm3时，电池具最佳的综合电性能。较低的胶含量及适中的压实密度有利于降低电池内阻，提升电池倍率性能和综合电性能。最后，本文对未来水性胶黏剂的研究方向进行了展望。

关键词: 磷酸铁锂, 水性胶黏剂, 锂离子电池

Abstract: Binder is indispensable and also has a direct impact on the performance of lithium-ion batteries. The introduction of aqueous binders into the manufacturing process of lithium-ion batteries can be more environmentally friendly, and meanwhile decrease the manufacturing cost and bring great economic benefit by its development and application. In this work two kind of polyacrylate binders LA and LB were used in LiFePO4 electrodes and the electrochemical performance of the prepared electrodes were investigated. Electrochemical test showed that the oxidation potential of the polyacrylate binder was about 4.65 V. Due to its higher oxidation potential, the polyacrylate binder is more suitable for the cathode of lithium-ion batteries. In comparison with LA, the LB binder showed better thermal stability with a decompose temperature of 318 ℃. Lithium ion diffusion coefficients for LA and LB electrodes were 6.2×1014 cm2/s and 1.8×1014 cm2/s, respectively. The effect of LA and LB binders on the electrode manufacturing properties, the battery capacity, rate performance, and cycle life were detailedly investigated and the optimized strategy for the application of aqueous binders in the LiFePO4 based electrodes were obtained. The results indicated that 3% of the LA binder content, 2.5% of the LB binder content, and 2.25 g/cm3 of the compaction density are the optimized condition for the batteries to obtain a best cycle life and overall performance.

Key words: LiFePO4, aqueous binders, lithium-ion batteries