锂离子电池硅负极粘结材料的研究进展

Research progress of silicon negative bonding materials for lithium ion batteries

摘要:

硅基负极材料因具有较高的理论比容量 4200 mAh/g，已成为国内外新能源锂离子电池负极材料领域研究热点课题。然而，由于硅基材料体积膨胀率高达400%，经多次充放电循环后，硅颗粒会发生破裂和粉化使其在电极基体上易脱落，从而导致电池容量衰减快、寿命短的技术缺陷。为缓解硅颗粒巨大体积变化产生的应力以及维持电极完整性，国内外科学研究者们从电池组成上出发，对活性材料、导电剂、粘结剂、电解液等进行系统研究，其中对聚合物粘结剂改性是一种实现其高寿命、抗衰减的有效手段之一。基于锂离子硅基负极材料优异特性及粘结材料的研究现状，综述了硅基负极组成、结构、性能、作用原理、分子间作用机制以及负极粘结剂的分子结构设计，探讨其对硅基锂离子电池电化学性能的影响规律，为锂离子电池硅基负极粘结材料的应用与开发提供理论和实践指导。

Abstract:

Silicon-based anode material has become a hot topic in the field of new energy lithium-ion battery anode material because of its theoretical ratio of 4200mAh/g. However, due to the volume expansion rate of silicon-based material stoking rate of up to 400%, after multiple charge and discharge cycle, the silicon particles will rupture and powder it on the electrode substrate easily shed, resulting in the rapid decay of battery capacity, short life of the technical defects. In order to alleviate the stress caused by the huge volume change of silicon particles and maintain electrode integrity, scientific researchers at home and abroad from the composition of the battery, the active materials, conductive agents, binders, electrolytes and other systematic research, in which the polymer binder modification is a high life, anti-attenuation of one of the more effective means. Based on the excellent properties of lithium-ion silicon-based anode materials and the research status of lithium-ion battery anode bonding materials, the molecular chain design of silicon-based anode composition, structure, performance, action principle, molecular-to-molecular mechanism and anegative adhesive is reviewed, the influence law on the electrochemical properties of silicon-based lithium-ion battery is discussed, and theoretical and practical guidance is provided for the application and development of lithium-ion battery silicon-based negative-adhesive materials.