Structure and cathode properties of LiCoPO/sub 4/ and Li/sub 2/CoPO/sub 4/F for high-voltage Li-ion batteries

As a new high-voltage cathode candidate for post 4 V cathode, ordered-olivine LiCoPO/sub 4/ and fluoride phosphate Li/sub 2/CoPO/sub 4/F were synthesized by solid-state reaction. Their structures were identified by neutron diffraction. The 5 V discharge profiles were demonstrated using coin-type cells. Two important issues for commercial use, metal dissolution and oxygen release at elevated temperature, were tested.