Preparation of cathode materials for Li-ion cells by acid dissolution

Abstract

New synthesis route called acid dissolution method, preparing the high-performance cathode materials for the lithium-ion cells, was successfully developed. In this method, insoluble starting materials such as metal carbonates or metal hydroxides are dissolved in strong organic acidic solution which contains a chelating agent. And then, the solvent of the solution containing starting materials is eliminated to obtain the xerogel of the initial solution whose chemical form is expressed as Li[MA(3)], where M is a transition metal atom and A is the anion of the organic acid. The xerogel is then calcined at the high temperature to obtain polycrystalline cathode materials. In this work, the applicability of this method was demonstrated synthesizing a polycrystalline single-phase LiCoO2 using lithium carbonate, cobalt hydroxide as the insoluble starting materials and the acrylic acid as a chelating agent. The synthesized powders calcined at 800 degrees C showed a good electrochemical performance in the half-cell test. (c) 2004 Elsevier B.V. All rights reserved.