Nanocarbon Current Collectors for Aqueous Batteries

Thursday, 1 June 2017: 10:20
Churchill C1 (Hilton New Orleans Riverside)
J. Hayden, C. F. Lin, W. Luo (University of Maryland, College Park), G. W. Rubloff (Nanostructures for Electrical Energy Storage (NEES)), and L. Hu (University of Maryland)
Carbon materials are a promising alternative to metal current collectors that are currently used in aqueous batteries, because of their light weight, high electrical conductivity, and promising corrosion resistance. In this report, we investigate the corrosion resistance of multiple flexible and robust nanocarbon current collectors (NCCCs) for aqueous battery applications.

We have fabricated a number of polymer-nanocarbon composite materials to serve the purpose, including activated carbon cloth (ACC) with carbon nanotubes (CNTs) and cellulose nanofibers combined with CNTs (CNT/CNF), both of which exhibit high conductivity and mechanical strength.

We evaluated durability of these composites under potentiostatic stress in conditions mimicking those of lead-acid and nickel metal hydride (NiMH) batteries in an attempt to expose the carbon current collectors to the most severe conditions they would experience in an aqueous battery. Cyclic voltammetry and Fourier transform infrared spectroscopy (FTIR) were used to characterize the oxidation of the NCCCs after holding them at stressing potentials for long periods of time. Stress-strain and four-point probe measurements were also taken before and after holding potential to evaluate changes in mechanical strength and DC conductivity of the NCCCs.

The CNT/CNF show improved electrochemical stability in acidic conditions compared to ACC while maintaining reasonable mechanical and electrical properties, and thus they are promising as alternative current collectors in an acidic aqueous battery such as lead-acid. We are also exploring other variations of nanocarbon-based current collectors and the use of atomic layer deposition to further develop NCCC technology options.