Feasibility study of carbon cloth for 3D integrated flexible cathode of lithium-ion battery

Abstract

The carbon cloths made of carbon fiber as 3D integrated cathode for lithium-ion batterie were studied. The graphitization degree of three types of carbon cloths after heat treatment were qualitatively analyzed and quantitatively calculated. Using lithium metal as the counter electrode, the graphitized carbon cloth electrodes show first discharge specific capacities of 83.6, 94.5 mAh∙g-1 and 115.2 mAh∙g-1 under 0.1-0.5 V, respectively. After 50 cycles, the specific capacities of carbon cloth electrodes remain 55.0, 80.0 mAh∙g-1 and 88.0 mAh∙g-1.With LiFePO4-loaded graphitized carbon cloths as cathodes, the initial discharge specific capacities of electrodes are 73.2, 109.5 mAh∙g-1 and 130.2 mAh∙g-1, respectively. The carbon cloth whose graphitization degree is 76.02% shows stable specific capacity of about 90.0 mAh∙g-1 after 50 cycles, and shows better comprehensive performances. This carbon cloth is more suitable for the integrated flexible cathode of lithium-ion batteries. By establishing the mechanical model of the interaction between LiFePO4 particles and carbon fiber, the relationship between mechanical, electrical and electrochemical properties of the integrated cathode were discussed.Using carbon cloth as an integrated cathode for lithium-ion batteries can simplify the conventional production process and innovate its production process.

Keywords

• lithium-ion battery
• carbon cloth
• graphitization degree
• 3d integrated flexible cathode
• conductivity