Synthesis, characterization and electrochemical studies on LiCoAsO4

LiCoAsO4 is synthesized by solid state reaction method and its crystal structure has been refined by the Rietveld method using powder X-ray diffraction data. LiCoAsO4 crystallizes in olivine structure with space group Pnma and orthorhombic lattice parameters are a = 10.4614(2) Å, b = 5.9970(1) Å and c = 4.8866(1) Å. Electrochemical studies reveal that in LiCoAsO4, lithium is deintercalated and intercalated at high voltage ∼5.0 V. On the other hand, the compound can react with about 9Li on discharge to 0.05 V. A reversible capacity of ∼100 mAh/g is obtained in the voltage range 1.0–2.5 V.