(743b) Modifications of Silicon Nanoparticles/Graphene Sheets Composite Anode to Enhance Lithium Ion Battery Performance

Development of lithium ion batteries with improved capacity and cycle performance are in the forefront of efforts to increase the electrification of current-age vehicles. Lately, much attention has been focused in the use of silicon-based anode materials mainly due to their theoretical capacity (4,200 mAh/g) which is more than 10 fold of the traditional graphite anodes. However, due to the increased accommodated lithium ions, silicon’s volume varies by 400% causing pulverization and loss of electrical contact. Due to this, strategies have led to the use of nano-sized Si and incorporation of Graphene to be able to mitigate volume variation and therefore produce an anode material with improved capacity and cyclability. In this project, we are presenting modifications of Si nanoparticles (SiNPs) and Graphene sheets (GSs) that form a standalone SiNP/GS composite anode. SiNPs are prepared with improved dispersion/distribution, and various carbon-based coating to improve electrochemical rate and stability. GS modifications involve sheet size and morphological variations to improve the charge-discharge reaction mechanisms (pathway). The efforts are investigated thoroughly by spectroscopy, microscopy and electrochemical techniques. The combination of such component engineering tasks is directed to produce the composite anode demonstrating enhanced capacity retention and rate performance.