Sub/surface dual-modification engineering empowering single-crystalline Ni-rich cathodes with superior long-term cyclability
Sub/surface dual-modification engineering empowering single-crystalline Ni-rich cathodes with superior long-term cyclability
研究概述
一步煅烧对单晶高镍NCM83进行MgAl2O4包覆及Al/Mg梯度掺杂，促进锂扩散、抑制晶格氧流失及界面副反应。改性正极200次循环后容量保持92.0%；与石墨配对的软包电池在3.0–4.2 V下循环1000次后保持超过86.5%。
谱图与表征信息
Fig. 1. (a, b) SEM images of SCNCM83 and SCNCM83-3AMO. (c) HAADF-STEM images of SCNCM83. (d, e) HRTEM and HAADF-STEM images of SCNCM83-3AMO. (f) EELS spectra of the Ni L-edges and O K-edges extracted from the surface to the inside region of SCNCM83-3AMO. (g) Ni K-edge XANES spectra, (h) corresponding FT-EXAFS spectra, and EXAFS WT images of SCNCM83 and SCNCM83-3AMO.
Fig. 4. Ni K-edge spectra for (a) SCNCM83 and (b) SCNCM83-3AMO collected from the cathodes before and after 50 and 100 cycles at 4.5 V and (c) comparison of derivative plots for the pre-edge peaks after 100 cycles. (d) Corresponding EXAFS analysis and (e, f) 2D FT contour plots. (g, h) In situ DEMS analysis of SCNCM83 and SCNCM83-3AMO