Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applicat...Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applications.Herein,a perovskite LiTaO_(3) strengthening network along the grain boundaries is designed to enhance the mechanical and structural stability of polycrystalline LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) by suppressing the anisotropic volume variation and retard the internal strain.Notably,the perovskite-modified LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode material exhibits significantly improved cyclability and rate capacity.Such enhanced electrochemical behavior can be ascribed not merely to the compacted particle,where the LiTaO_(3) interface effectively inhibits electrolyte infiltration,but also to the structural stability in terms of inhibiting lattice oxygen release through the introduction of strong Ta-O bonds,thereby restraining interfacial side reactions and surface phase transitions.This work provides precise control over grain boundaries to suppress the inter-strain,taking care of the crystal structure and interface properties.展开更多
基金supported by the National Natural Science Foundation of China [NSFC, grant numbers U22A20113 and 52261135543]。
文摘Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applications.Herein,a perovskite LiTaO_(3) strengthening network along the grain boundaries is designed to enhance the mechanical and structural stability of polycrystalline LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) by suppressing the anisotropic volume variation and retard the internal strain.Notably,the perovskite-modified LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode material exhibits significantly improved cyclability and rate capacity.Such enhanced electrochemical behavior can be ascribed not merely to the compacted particle,where the LiTaO_(3) interface effectively inhibits electrolyte infiltration,but also to the structural stability in terms of inhibiting lattice oxygen release through the introduction of strong Ta-O bonds,thereby restraining interfacial side reactions and surface phase transitions.This work provides precise control over grain boundaries to suppress the inter-strain,taking care of the crystal structure and interface properties.
