High-capacity high-Ni low-Co Li-rich layered oxides via adjusting Li2MnO3 content and Li/Ni mixing defects

The reasonably regulated Li2MnO3 phase content and Li/Ni disordering are developed to obtain a high-capacity high-Ni low-Co LLO Li1.167Ni0.222Mn0.537Co0.074O2 (L2-1), by two-step adjustment of the Ni/Mn and Li/Mn ratios. Based on the XRD refinement and density functional theory calculation, it is found that a proper Li2MnO3 content (36.6%) and a high Li/Ni disordering (5.93%) in LLOs play a crucial role in achieving high-capacity and high-voltage performance. [Display omitted] •A high-capacity high-Ni Li-rich layered oxide with > 280 mAh g−1 was obtained.•Li2MnO3 content and Li/Ni mixing are controlled to realize the high capacity.•All high-Ni Li-rich layered oxides are designed based on the calculation models. Li-rich layered oxides (LLOs) have been considered as the promising candidate cathodes for the next high-energy Li-based batteries, but suffer from poor rate capability, lower discharge voltage, and persistent voltage fade. Appropriately increasing the Ni content in LLOs tends to improve rate capability, discharge voltage, and stability. However, the high-Ni LLOs are likely to have inferior O2−/− redox activities, causing lower capacities, typically