Preparation and lithium intercalation of a new vanadium oxide with a two-dimensional structure

A new type of V₂O₅ which was synthesized by a reaction of metallic vanadium with hydrogen peroxide solution, takes a random layer lattice structure based on the a-b plane of orthorhombic V₂O₅. Electrochemical intercalation of Li into this two-dimensional compound was investigated in a LiClO₄/propylene carbonate solution. Discharge and charge cycles carried out in the voltage range 2.0 to 4.3 V showed a high specific capacity of about 310 Ah/kg. The film fabricated on an ITO glass substrate by the spin-coating technique, using a water based solution of the new V₂O₅, exhibited electrochromism. The magnitude of optical density change at 380 nm between coloration and decoloration of the film of 8000 Å thickness, is about 0.7.