Chitosan, a new and environmental benign electrode binder for use with graphite anode in lithium-ion batteries

• Published in: Electrochimica acta 2013-08, Vol.105, p.378-383
• Main Authors: Chai, Lili, Qu, Qunting, Zhang, Longfei, Shen, Ming, Zhang, Li, Zheng, Honghe
• Format: Article
• Language: English
• Subjects: Anodes; Binders; Chitosan; Electrochemical impedance spectroscopy; Electrode binder; Electrodes; Graphite; Graphite anode; Lithium batteries; Lithium-ion batteries; Polyvinylidene fluorides
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2013.05.009

•Chitosan is used as a new electrode binder for graphite anode.•Electrochemical properties of the chitosan-based electrode are compared with that of PVDF-based one.•Electrochemical performances of the graphite anode are improved by using chitosan binder.•Chitosan binder facilitates the formation of a thin, homogenous and stable SEI film of the electrode. Chitosan was applied as the electrode binder material for a spherical graphite anode in lithium-ion batteries. Compared to using poly (vinylidene fluoride) (PVDF) binder, the graphite anode using chitosan exhibited enhanced electrochemical performances in terms of the first Columbic efficiency, rate capability and cycling behavior. With similar specific capacity, the first Columbic efficiency of the chitosan-based anode is 95.4% compared to 89.3% of the PVDF-based anode. After 200 charge–discharge cycles at 0.5C, the capacity retention of the chitosan-based electrode showed to be significantly higher than that of the PVDF-based electrode. Electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) measurements were carried out to investigate the formation and evolution of the solid electrolyte interphase (SEI) formed on the graphite electrodes. The results show that a thin, homogenous and stable SEI layer is formed on the graphite electrode surface with chitosan binder compared with that using the conventional PVDF binder