Al Current Collectors for Li-Ion Batteries Made via an Oxidation Process in Ionic Liquids

Efficient electrical wiring of electrodes is a key issue in the design of Li-ion batteries using insulating compounds. Approaches acting at the material level are being pursued by combining techniques to decrease the particles size and to coat them with carbon. Here, we report the texturation of the Al current collector as an additional mean to improve electrode kinetics. Bulk aluminum substrates were oxidized from [EMIm]TFSI/AlCl3 electrolytic baths using cyclic voltammetry techniques. A needlelike morphology was obtained after oxidation. Electrodes using this substrate and LiFePO4 powders as the active material were shown to display excellent capacity retention and high rate capability. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3511717] All rights reserved.