Microstructure and Performance of SnO₂-C Composite Coating with Network Structure Used for Lithium Ion Batteries Anode

The dimethylformamide (DMF) solution containing SnCl₂, polyacrylonitrile (PAN) and poly(methyl methacrylate) (PMMA) was coated on the surface of Cu foils by simple knife coating, and then calcined in vacuum. The SnO₂-C composite coating with three dimensional network structure was fabricated successfully. The micro-structure of the composite coating was characterized and the performance of network structure SnO₂-C composite coating as lithium ion batteries anode was tested. The results show that the coating presented the continuous network structure formed by interconnected carbon based branches with width of 0.1-1 μm which consisted of amorphous carbon matrix, SnO₂ nano-particles with size of 10-150 nm and micro-pores with size of 1-5 nm. When the composite coating was employed as anodes of lithium ion batteries, after 100 times cycling under current density of 50 mA·g^-1, the composite coating electrodes exhibited specific capacity of 642 mAh·g^-1 without capacity fading during the cycling. The specific capacity of the electrodes under current density of 10 A·g^-1 was 43% of the specific capacity under current density of 50 mA·g^-1. The composite coating had the good electrochemical performance.