High energy density lithium-ion batteries with carbon nanotube anodes

Abstract

Recent advancements using carbon nanotube electrodes show the ability for multifunctionality as a lithium-ion storage material and as an electrically conductive support for other high capacity materials like silicon or germanium. Experimental data show that replacement of conventional anode designs, which use graphite composites coated on copper foil, with a freestanding silicon-single-walled carbon nanotube (SWCNT) anode, can increase the usable anode capacity by up to 20 times. In this work, a series of calculations were performed to elucidate the relative improvement in battery energy density for such anodes paired with conventional LiCoO₂, LiFePO₄, and LiNiCoAlO₂ cathodes. Results for theoretical flat plate prismatic batteries comprising freestanding silicon-SWCNT anodes with conventional cathodes show energy densities of 275 Wh/kg and 600 Wh/L to be theoretically achievable; this is a 50% improvement over today’s commercial cells.