生物高分子在锂离子电池硅负极中的研究进展  

Research progress of biopolymers in Si anodes for lithium-ion batteries

作　　者：刘大进 吴强 何仁杰 余创 谢佳 程时杰[1] LIU Dajin;WU Qiang;HE Renjie;YU Chuang;XIE Jia;CHENG Shijie(School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China;School of Materials science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China)

机构地区：[1]华中科技大学电气与电子工程学院,湖北武汉430074 [2]华中科技大学材料科学与工程学院,湖北武汉430074

出　　处：《储能科学与技术》2021年第6期2156-2168,共13页Energy Storage Science and Technology

基　　金：国家自然科学基金项目(51821005,U1966214)。

摘　　要：硅因其超高的理论比容量,有望成为下一代高性能锂离子电池的负极材料。硅在充放电过程中的剧烈体积膨胀会引起颗粒粉化、SEI膜过量生长以及活性物质失去电接触等问题,最终导致容量快速衰减。开发新型硅负极黏结剂和硅碳复合是提升硅负极性能的重要策略。生物高分子材料成本低、环境友好且富含有机官能团,非常适合用来开发低成本、高性能硅负极黏结剂,也适合作为碳前体合成硅碳复合材料。本文综述了近年来基于生物高分子的硅负极黏结剂和以生物高分子为碳前体的硅碳复合材料的研究进展。本文重点介绍了基于海藻酸钠、壳聚糖、淀粉的硅负极黏结剂,总结出生物高分子基黏结剂的主要改性方法有接枝特殊官能团、与其他聚合物共混或交联。基于这些改性方法,可分别提升黏结剂的黏附性、导电子或离子能力以及实现3D网络结构的构建。本文重点归纳了以纤维素、壳聚糖、淀粉、木质素为碳前体的硅碳复合材料,分别介绍了这些复合材料的性质、结构特点,及其对电化学性能的影响。基于以上分析,本文也指出了当前基于生物高分子的硅负极黏结剂和以生物高分子为碳前体的硅碳复合材料的不足,为其下一步发展指明了方向。Si is regarded as one of the most promising anode materials for next-generation high-performance lithium-ion batteries due to its ultrahigh theoretical lithium storage capacity.However,due to the large volume change of Si during lithiation/de-lithiation,Si anodes suffer from particle pulverization,the formation of unstable solid-electrolyte interphase(SEI)layer,and the loss of electric contact,resulting in rapid decay in capacity.Two common strategies for improving the electrochemical performance of Si anodes are the development of novel binders and the fabrication of Si/C composites.Biopolymers are low-cost,environmentally friendly,and rich in polar groups,making them ideal materials for the development of silicon anode binders and the fabrication of Si/C composites.We summarize recent research development of biopolymer-based binders for Si anodes and Si/C composites with biopolymers as carbon precursors in this review.Sodium alginate(SA),chitosan(CS),and starch-based binders are discussed in detail.The most common biopolymer-based binder modification strategies are summarized. Biopolymers are typically modified by grafting specialgroups, mixing with other polymers, or crosslinking to improve adhesion, electron/ionconductivity, or the formation of 3D networks. The physical and chemical properties, as well asthe microstructures, of Si/C composites containing cellulose, chitosan, starch, and lignin ascarbon sources, as well as their influence on electrochemical properties, are specificallydiscussed. On this basis, the deficiencies and potential development directions of currentbiopolymer-based binders and Si/C composites containing biopolymers as carbon sources areidentified.

关 键 词：锂离子电池 硅负极 生物高分子 黏结剂 硅碳复合材料 

分 类 号：TM911[电气工程—电力电子与电力传动]