Aluminum and Indium Co-Modified Ni-Rich Layered Cathode with Enhanced Microstructure and Surface Stability for Lithium-Ion Batteries

Ni-rich layered oxides are considered as promising cathodes for next-generation lithium-ion batteries. However, they still suffer microstructure and surface instability particularly under high operating voltage, leading to rapid capacity fading and battery failure. In this context, Ni-rich layered cathodes (LiNi x Co y Mn 1− x − y O 2 ; LNCM) with aluminum and indium co-modified crystal and surface structures are developed by a simple one-pot calcination approach. Battery tests show that the Al and In co-modified LNCM electrodes demonstrate remarkably enhanced rate capability and cycling stability compared with the pristine LNCM, Al-doped LNCM, and In-modified LNCM counterparts. Further characterizations reveal a simultaneous suppression of cracking and resistive film growth. The improved microstructural and surface stability originate from the synergistic functions of Al and In co-modification. The incorporation of Al 3+ into transition metal slab significantly reduces the Li + /Ni 2+ antisite, which noticeably mitigates the undesired layer to rock-salt phase transformation. The In 3+ dopant dispersed in Li interslab can dissipate the anisotropic lattice strain, enabling greatly improved reversibility of H2↔H3 phase transition occurred in delithiation-lithiation processes. Meanwhile, the synchronously formed LiInO 2 adherent coatings deplete lithium residues, facilitate lithium-ion transfer, and resist electrolyte corrosion. Microstructure and surface engineering through Al and In co-modification offer a promising design strategy for Ni-rich layered cathodes.