The Progress and Prospects of Doping Modification of High-Nickel Ternary Cathode Materials

High-nickle ternary cathode materials(NCM) have become the core of high power density lithium-ion batteries by virtue of its outstanding specific capacity. But the lattice distortion caused by its deep lithium extraction, the disordered arrangement of lithium-ion and nickle-ion, interface side reaction restricted the cycle life and safety. This article systematically reviewed the latest advancements in the doping modification of element to enhance the structural-interface-dynamic stability of the NCM system: the impurity cations can expand the inter-layer spacing of the lithium layer, inhibit disordering, and reduce lattice strain by occupying the transition metal sites; the impurity anions noticeably enhance the transition metals and oxygen bonds, reduce oxygen vacancies and the mixed arrangement of transition metals; the multi-ion co-doping technology achieves a comprehensive performance improvement through the synergy of “structure + interface”, indicating that element doping modification has advanced from the “trial-and-error of single atoms” stage to the stage of “structural-interface coordinated regulation” .This article summarizes the existing problems of element doping modification of high-nickel ternary materials, providing reference ideas for the future optimization of doping modification techniques.