In the Li-ion batteries (LIBs), one of the main functions of binder is used to stabilize the electrode structure. Although the content of binder is little, it has great influence on the performance of the battery. Polyvinylidene fluoride (PVDF) is the main commercial binder at present, but its application in different kinds of active substances has different defects. Therefore, the appropriate binders should be selected for different cathode or anode active materials. In cathode, lithium iron phosphate (LFP) and ternary materials (NCM) exihibit poor conductivity and ionic conductivity due to their intrinsic crystal constructure. Therefore, the binder with higher ion diffusion coefficient can obviously improve the performance of battery. During the process of charging and discharging, "shuttle effect" is one of the main factors leading to poor performance of lithium sulfur battery. The binders with oxygen-containing functional groups have strong capture ability to lithium polysulfide, which can significantly improve battery performance. For anode materials in LIBs, traditional PVDF binder is easy to react with carbon based materials to form SEI film. Lithium salt is easily deposited on the surface of the active material, which affects the performance of the battery. Therefore, during the charging and discharging process, the binder that can produce a uniform and stable SEI film can significantly improve the battery performance. Because the SEI film can prevent the active material from falling off and promote Li+ migration. Then, the volume of silicon-based anode material changes greatly during the process of charging and discharging, and these volume changes make the active material fall off from the collector easily. The binders with moderate viscoelasticity and three-dimensional network structure can make the volume expanded of the silicon-based anode reversibly and the loss of active material is reduced. Therefore, this type of binder can significantly improve the battery performance. In addition, spinel-structured lithium titanium oxide (LTO) exhibit poor conductivity, conductive polymer binder will be one of main research directions in the future. This article reviewed the binder applied in different active materials based on Li-ion batteries in recent years. The effects of binders on the Li-ion cells performance were mainly introduced, and future prospects of research and applications of binders in different kinds of LIBs were presented. © 2021, Materials Review Magazine. All right reserved.
