First principles investigation of thermodynamic and kinetic properties of lithium transition metal oxides

Anton Van Der Ven, Massachusetts Institute of Technology

Lithium transition metal oxides (Lix MO2 with M = transition metal) are ideally suited to serve as cathode materials in the next generation of rechargeable lithium batteries. A lithium battery consists of an anode (which is metallic lithium) and a cathode (the lithium transition metal oxide) separated by an electrolyte. In use, lithium ions are released at the anode, travel through the electrolyte and are intercalated into the cathode material. Lithium transition metal oxides exhibit a high voltage, can undergo large variations in lithium concentration and are stable under repeated removal and insertion of lithium ions. Currently the most important cathode material is LixCoO2. In this work we have investigated the thermodynamic phase stability of LixCoO2 as a function of the lithium concentration. We have also calculated the mobility of the lithium ions within the CoO2 crystal structure. Both quantities are essential to enable an intelligent optimization and design of existing and new cathode materials.

Abstract Author(s): Anton Van Der Ven