The Cu–Y co-doping LiNi0.5Mn1.5O4 with modified morphology and enhanced electrochemical property for a 5 V lithium-ion battery

• Published in: Journal of materials science. Materials in electronics 2022, Vol.33 (1), p.283-297
• Main Authors: Lin, Fangchang, Wu, Hongming, Chen, Tianci, Xu, Dinghong, Zhou, Dengfeng, Yan, Wei, Guo, Jianbing
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper; Diffusion rate; Discharge; Doping; Electrochemical analysis; Electrode polarization; Ion diffusion; Lithium; Lithium-ion batteries; Materials Science; Morphology; Ohmic drop; Optical and Electronic Materials; Rechargeable batteries; Sol-gel processes; Transition metals
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-021-07292-5

LiNi 0.5− x Cu x Mn 1.48 Y 0.02 O 4 ( x  = 0.02, 0.03, 0.04) and LiNi 0.5 Mn 1.5 O 4 (LNMO) samples were prepared successfully via the sol–gel method. The lattice parameter and the degree of Ni/Mn disorder for LNMO samples were increased by doping Cu 2+ and Y 3+ ions, which is benefit for improving lithium-ion diffusion rate. The Cu–Y co-doped samples possessed truncated octahedral morphologies with (111) facet and exposed (100) facet by modified the co-doped Cu–Y content. The (100) facet helped to accelerate the Li + ion diffusion while the (111) facet inhibited the dissolution of transition metals at the solid interface. The LiNi 0.47 Cu 0.03 Mn 1.48 Y 0.02 O 4 (0.03 Cu–Y) sample exhibited high initial discharge specific capacity of 145.7 mAh g −1 which was far higher than that of pristine sample (113.8 mAh g −1 ). After 100 cycles at 1 C, the 0.03 Cu–Y sample retained discharge specific capacity of 137.2 mAh g −1 with superior retention of 96.79% while the undoped sample only retained 108.8 mAh g −1 and the retention is 95.79% at the same condition. The improved electrochemical property of the Cu–Y co-doped sample maybe attribute to the stable structure that decrease Ohmic polarization and the suitable morphology that is conducive to accelerate the Li + ion diffusion.