Materials issues in lithium ion rechargeable battery technology

Lithium ion rechargeable batteries are predicted to replace Ni/Cd as the workhorse consumer battery. The pace of development of this battery system is determined in large part by the availability of materials and the understanding of interfacial reactions between materials. Lithium ion technology is based on the use of two lithium intercalating electrodes. Carbon is the most commonly used anode material, while the cathode materials of choice have been layered lithium metal chalcogenides (LiMX2) and lithium spinel-type compounds. Electrolytes may be either organic liquids or polymers. Although the first practical use of graphite intercalation compounds as battery anodes was reported in 1981 for molten salt cells and in 1983 for ambient temperature systems, it was not until Sony Energytech announced a new lithium ion intercalating carbon anode in 1990, that interest peaked. The reason for this heightened interest is that these electrochemical cells have the high energy density, high voltage and light weight of metallic lithium, but without the disadvantages of dendrite formation on charge, improving their safety and cycle life. This publication will review recent developments in the field and materials needs that will enhance future prospects for this important electrochemical system.