Mg,Ti-base surface integrated layer and bulk doping to suppress lattice oxygen evolution of Ni-rich cathode material at a high cut-off voltage

Zero-Strain Cathodes for Lithium-Based Rechargeable Batteries: A Comprehensive Review

“…HR-TEM can directly reveal lattice changes of CAM particles . Peng et al synthesized NCM@MTP with reduced lattice oxygen evolution by Mg, Ti codoping, and observed NCM811 and NCM@MTP particles after 200 cycles through HR-TEM. Rock salt phase impurities were observed in the interior of NCM811 after 200 cycles (Figure a), whereas the R m layer was well maintained in NCM@MTP with the (101) and (006) planes of H_NCM (Figure b), , implying suppressed phase transformations and, thus structural integrity.…”

“…HR-TEM images and enlarged images from marked regions of (a) NCM and (b) NCM@MTP after 200 cycles. Reprinted from ref . Copyright 2022, with permission from Elsevier.…”

“…Oxygen evolution can lead to irreversible phase transition and strong anisotropic lattice strain, resulting in microcracks. Peng et al 84 developed a Mg/ Ti-based surface integrated layer comprising Mg 2 TiO 4 and Mg 0.5−x Ti 2−y (PO 4 ) 3 on the H_NCM particle surfaces and inhibited lattice oxygen evolution in a highly charged state (Figure 4e). Mg and Ti bulk codoping alleviated Li + /Ni 2+ mixing and stabilized the lattice structure.…”

“…(e) Schematic of the modification process and advantages of the NCM@MTP. Reprinted with permission from ref . Copyright 2022 American Chemical Society.…”

Construction of a nickel-rich LiNi0.83Co0.11Mn0.06O2 cathode with high stability and excellent cycle performance through interface engineering

“…To solve those problems, many effective strategies, such as element doping, surface coating, and single crystal materials, have been developed to improve the electrochemical performance of Ni-rich cathodes. Peng et al 25 demonstrated that Mg-Ti co-doping can typically inhibit the lattice oxygen release of nickel-rich materials during deep charging. Meanwhile, partial magnesium and titanium were doped onto the surface of the particles to form the Li-magnesium-titanium-oxide layer with high electronic and ion conductivity, which endowed excellent cycle stability at high temperature and high voltage.…”