Soft-combustion (wet-chemical) synthesis of a new 4-V class cathode-active material, LiVMoO6, for Li-ion batteries

A new, 4-V class, lithiated transition metal oxide cathode, LiVMoO6, has been synthesized by a novel soft-combustion (wet chemical) low temperature (LT) method that presents advantages compared to the classical ceramic method, namely, in terms of phase purity, surface texture and size, preparation time, costs and electrochemical performances of the resulting products. The structural properties of the newly synthesized product have been examined by means of X-ray diffraction studies (XRD). The thermal reactions which occur during the soft-combustion of the precursor mixture have been examined by DTA/TG techniques. It has been found that the layered LiVMoO6 can only be obtained upon calcining the precursor at 540 degrees C, beyond which the compound will thermally be reduced to LiVMoO5 which exhibits inferior structural characteristics for the intercalation/deintercalation reactions. The product (LiVMoO6) thus prepared exhibits submicrometre spherical grains (<1 mu m) whose specific surface area is 5.01 m(2)/g. The intercalation/deintercalation (redox) kinetics of the above product has been studied and its suitability as cathode material in actual electrochemical cells is discussed in the light of electrochemical properties. (C) 2000 Elsevier Science Ltd. All rights reserved.