PNNL

Abstract

A new Li-ion battery cathode, ‘LT-LiMn0.5Ni0.5O2’ (where LT refers to its relatively low synthesis temperature, 400 ?C), with structurally-integrated and partially-disordered lithiated-spinel and layered components, has been identified. Electrochemical data and X-ray absorption analyses indicate that Li/LT-LiMn0.5Ni0.5O2 cells operate between 5.0 and 2.5 V with remarkable cycling stability, predominantly by redox reactions on the nickel and oxygen ions, and to a lesser extent on the manganese ions. The partially-disordered lithiated-spinel and layered component structures yield identical X-ray diffraction patterns and are thus uniquely intergrown as shown by high resolution electron microscopy.