Carbon-based Nanocomposite Materials for High Energy Density Rechargeable Batteries

Graphite anode and oxide based cathodes in the current lithium ion batteries can only provide moderate energy-storage capability and therefore are difficult to meet the increasing demands for advanced energy storage systems. Silicon, tin, and some transition metal oxides are promising high-capacity anode materials for lithium ion batteries.

However, these materials suffer from huge volume change during charge and discharge, which leads to poor cycling performance. Sulfur is one of the most promising cathode materials for rechargeable lithium batteries with a high theoretical capacity of about 1675 mAh g-1.

However, the current lithium-sulfur cells suffer from the low electronic conductivity of sulfur electrodes and the high solubility of long chain polysulfide ions in organic solvent-based electrolytes. To solve these problems, we use novel carbon nanostructures, such as graphene, graphene oxides, and porous carbon nanofibers as matrices to fabricate carbon-electrochemically active material nanocomposites as anodes (such as graphene/Si, graphene/Sn, graphene/Fe3O4,, etc) and cathodes (such as graphene oxide/sulfur, porous carbon nanofiber/sulfur, etc.) for rechargeable lithium batteries.

Speaker: Dr. Yuegang Zhang, LBNL, Material Sciences Division

Room 521