Carbon nanotube net could extend battery lifetimes

Abstract

As scientists try to boost the lifetime and capacity of lithium-ion batteries, they’ve run into a problem. The electrode materials that would help the batteries store more energy tend to crack and ultimately pulverize during the charging cycle: Lithium ions make the material expand during charging and then contract during discharging. As this happens repeatedly, an inactive layer forms around the material and degrades battery performance. Taking a molecular approach to battery design, a team of chemists has developed a strategy to prevent such breakdown in anode materials. The team, led by Georgia Tech’s Elsa Reichmanis and Stony Brook University’s Amy C. Marschilok, created single-walled carbon nanotube (SWNT) nets that are anchored to the battery material via poly[3-(potassium-4-butanoate) thiophene], also known as PPBT. PPBT has carboxylate groups that coordinate with the polar surface of the battery material, and its thiophene backbone uses π bonding to interface with the SWNTs. Electrons