Enhancing surface oxygen retention through theory-guided doping selection in Li_1−xNiO₂ for next-generation lithium-ion batteries

Abstract

Using a collaborated in silico and experimental approach, we designed Sb-doped LiNiO2 with improved surface oxygen retention and electrochemical performance.

Resolving atomic-scale phase transformation and oxygen loss mechanism in ultrahigh-nickel layered cathodes for cobalt-free lithium-ion batteries

“…[4][5][6][7][8] Particularly, with the discovery of effective dopants that can inhibit oxygen loss in deep charged states, doped lithium nickelate (LiNiO 2 ; LNO) has recently become one of the most promising high-energy cathode materials for LIBs because of their high specific energy, long cycle life, and reduced cobalt content. [9][10][11][12] Despite extensive electrochemical studies on this system in the 1990s [13][14][15] and recent renewed interest, 7,[16][17][18] the intrinsic cycling instability which involves complex degradation behaviors of this material has plagued its commercialization. For example, the extraction of Li from LNO causes a detrimental phase transformation that involves considerable volume shrinkage and thereby deteriorated capacity retention and structural stability.…”

New Insights into Structural Evolution of LiNiO2 Revealed by Operando Neutron Diffraction

“…Evidently, a substantial contract of the c-lattice near the end of charge (SOC > ~75 %), i. e., due to H2-H3 phase transition, [28][29][30][31] is universally demonstrated to be the leading cause to the structural degradation of LNO. What is worse is the oxygen evolution, despite under active debate over its underlying mechanisms and reversibility, [24,30,32,33] accompanying the severe lattice distortion. While most studies [28][29][30][34][35][36] employ in situ/operando X-ray diffraction to monitor the structural evolution of LNO (or Nirich cathodes), little attention is paid to the discussion of local Li/Ni environments, for example, Li/NiÀ O bond lengths, as a function of Li content.…”

Revisiting the role of Zr doping in Ni-rich layered cathodes for lithium-ion batteries

“…can stabilize the lattice oxygen owing to the strong electron hybridization effect with the oxygen in the layered oxide system. 74,75 In addition, experimental studies have shown that these dopants enhanced the Ni-rich layered cathode cyclability by alleviating the lattice contraction, crack propagation, oxygen evolution, and surface reconstruction. [2][3][4][5] In particular, the stabilization of lattice oxygen by Ti doping has been previously evidenced by mRIXS and DFT calculation, with similar results as those for Zr doping.…”