Improved Rate Capability and Thermal Stability of LiNi0.5Co0.2Mn0.3O2 Cathode Materials via Nanoscale SiP2O7 Coating

Li δ P y O z –coated LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode materials doped with P and Si ions were prepared by direction reaction of LiOH and SiP 2 O 7 -coated Ni 0.5 Co 0.2 Mn 0.3 (OH) 2 precursors. The coated cathodes exhibited quite impressive results; rate capability was improved by almost 100% at a 7 C rate compared to pristine LiNi 0.5 Co 0.2 Mn 0.3 O 2 . Furthermore, the amount of heat generation at 4.5 V charge cut-off as a result of the evolution of oxygen was reduced by 79%, compared to pristine LiNi 0.5 Co 0.2 Mn 0.3 O 2 sample.