Surface in-situ reconstruction of LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode materials interacting with antimony compounds and the electrochemical performances
Abstract(#br)Interfacial stability is regarded as one of the greatest challenges in the commercialization of Ni-rich layered cathode materials for lithium battery. Surface modification can solve these issues to obtain superior electrochemical performances. Herein, LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode surface is reconstructed by a simple solid-state method using antimony oxides as modified agents. The modified mechanisms study show that the antimony oxides (Sb 2 O 5 ) can react with the surface lithium residues effectively and partial surface lattice lithium on the NCM811 surface to further construct the LiSbO 3 /Li–Sb– Me –O ( Me = Ni, Co, Mn) mixed coating layers. The uniform coating layer is mainly ascribed to the droplet spreading behaviors of the low smelting antimony oxides. The electrochemical measurements show that the Sb-modified NCM811 electrodes deliver 90.27% (180 mA g −1 ) and 96.07% (1440 mA g −1 ) capacity retentions over 3.0–4.3 V after 200 cycles, respectively, which are higher than 77.40 and 74.75% of the bare NCM811. The enhanced electrochemical performances are mainly benefitted to the enhanced the lithium transportation, the suppressed impedances increase and the more stable crystal structure
