Chemomechanically stable small single-crystal Mo-doped LiNi${}_{0.6}$Co${}_{0.2}$Mn${}_{0.2}$O${}_2$ cathodes for practical 4.5 V-class pouch-type Li-ion batteries

High voltage can cost-effectively boost energy density of Ni-rich cathodes based Li-ion batteries (LIBs), but compromises their mechanical, electrochemical and thermal-driven stability. Herein, a collaborative strategy (i.e., small single-crystal design and hetero-atom doping) is devised to construct a chemomechanically reliable small single-crystal Mo-doped LiNi${}_{0.6}$Co${}_{0.2}$Mn${}_{0.2}$O${}_2$ (SS-MN6) operating stably under high voltage (≥4.5 V vs. Li/Li${}^{+}$). The substantially reduced particle size combined with Mo${}^{6+}$ doping absorbs accumulated localized stress to eradicate cracks formation, subdues the surface side reactions and lattice oxygen missing meanwhile, and improves thermal tolerance at highly delithiated state. Consequently, the SS-MN6 based pouch cells are endowed with striking deep cycling stability and wide-temperature-tolerance capability. The contribution here provides a promising way to construct advanced cathodes with superb chemomechanical stability for next-generation LIBs. (© 2023 Wiley‐VCH GmbH)