Sacrificed template synthesis of Li1.2Ni0.13Co0.13Mn0.54O2 spheres for lithium-ion battery cathodes

Abstract

Porous and solid Li1.2Ni0.13Co0.13Mn0.54O2 spheres have been prepared by spherical Ni0.13Co0.13Mn0.54(CO3)0.8 and MnO2-sacrificed templates route. X-ray diffraction profiles show two kinds of Li1.2Ni0.13Co0.13Mn0.54O2 spheres have good layered structure with solid solution characteristic. Scanning electron microscope images reveal that the porous Li1.2Ni0.13Co0.13Mn0.54O2 spheres obtained from spherical carbonate precursor are composed of well-defined primary nanoparticles. These nanoparticles have the size of 100–300 nm, and some porous structure can be observed among these particles on the surface. The solid spheres obtained from MnO2 are made of tightly clustered nanoparticles. As lithium-ion battery cathodes, the porous spheres exhibit a high initial discharge capacity of 255.7 mAh g−1 at 0.1 C between 2.0 and 4.8 V. After 50 cycles, a discharge capacity of 177.7 mAh g−1 could be retained at 0.5 C. Even at high charge–discharge rate of 5 C (1,000 mA g−1), 121.4 mAh g−1 can be reached. But the solid spheres only deliver initial discharge capacity of 159.9 mAh g−1 at 0.1 C. Anyway, the different electrochemical performances of two samples should be attributed to the use of different sacrificed templates.