Pillar Effect in Ni-rich Cathode of Li-Ion Battery by NH3 Thermal Treatment

Abstract

Ni-rich layered LiNixMnyCozO2 (NCM) materials are used in lithium-ion batteries because of their high cathode capacity. The high nickel content, however, usually leads to severe capacity fading and structural collapse after repeated charging and discharging. To mitigate these problems, we heat-treated NCM in an NH3 atmosphere to form Ni2+ pillars between Li layers. The Ni2+ pillars improve the cycling stability of NCM by alleviating degradation of the Li layer. This is a simple and effective method for improving the stability of Ni-rich NCM.