Thermal Stability of LiCoPO[sub 4] Cathodes

Abstract

The thermal stability of cathodes charged to different lithium contents was studied by synchrotron diffraction and differential thermal analysis. Both olivine-like phases and appearing during the delithiation of are unstable upon heating, and decompose readily in the range . The decomposition of lithium-poor phases leads to gas evolution and the crystallization of . The role of carbon present in the electrochemically delithiated samples is discussed. The significantly lower stability of charged in comparison with is a serious challenge for the application of this material in rechargeable Li-ion batteries.