Synergistic effect in mesoporous SiO2 carbonaceous composites as anodes for lithium­ion battery

M. OTERO; D. BARRACO; G. LENER; K. SAPAG; A. GARCIA-BLANCO; E. LEIVA

Jujuy

Workshop; 3rd International Workshop on Lithium, Industrial Minerals and Energy; 2016

Universidad de Jujuy

Although graphite anodes have excellent properties for lithium battery such as good electronic and ionic conductivity, cyclability, safety, low potential, low cost, low voltage hysteresis, high specific capacity (~2.5 higher than LiCoO2), low volume expansion, etc. todays industrials demands require even better materials. The increase of the energy demand of portable devices and the revival of electric vehicles as future transportation media request the development of new technology. Most of the anode material research focuses on metal and alloys (Si, Sn, Al, Pb, etc.) because of their high gravimetric and volumetric capacity.  The combination of mesoporous SiO2 with carbonaceous structures may provide good anode materials for lithium ion batteries. The electrochemical dE/dV measurement and the DRX-insitu analysis indicate the irreversible formation of different silicates and silicon during the first cycles and the formation of LixSiy alloys during the following charge/discharge process.  We have synthetized composites that keep their properties during 100 cycles, at relatively high rate discharge rate.