Browsing by Author "Chen, YZ"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    A long cycle-life high-voltage spinel lithium-ion battery electrode achieved by site-selective doping
    (John Wiley & Sons, Inc, 2020-03-23) Liang, GM; Wu, ZB; Didier, C; Zhang, WC; Cuan, J; Li, BH; Ko, KY; Hung, PY; Lu, CZ; Chen, YZ; Leniec, G; Kaczmarek, SM; Johannessen, B; Thomsen, L; Peterson, VK; Pang, WK; Guo, ZP
    Spinel LiNi0.5Mn1.5O4 (LNMO) is a promising cathode candidate for the next-generation high energy-density lithium-ion batteries (LIBs). Unfortunately, the application of LNMO is hindered by its poor cycle stability. Now, site-selectively doped LNMO electrode is prepared with exceptional durability. In this work, Mg is selectively doped onto both tetrahedral (8a) and octahedral (16c) sites in the Fdurn:x-wiley:14337851:media:anie202001454:anie202001454-math-0001 m structure. This site-selective doping not only suppresses unfavorable two-phase reactions and stabilizes the LNMO structure against structural deformation, but also mitigates the dissolution of Mn during cycling. Mg-doped LNMOs exhibit extraordinarily stable electrochemical performance in both half-cells and prototype full-batteries with novel TiNb2O7 counter-electrodes. This work pioneers an atomic-doping engineering strategy for electrode materials that could be extended to other energy materials to create high-performance devices. © 2020 Wiley-VCH Verlag GmbH & Co
  • Thumbnail Image
    Item
    Three-dimensional stress distribution of surplus assembled 7050Al alloy ring and plug determined by neutron diffraction
    (Science China Press Co., Ltd, 2013-01-01) Sun, GA; Wang, XL; Wu, ED; Li, J; Chen, YZ; Chen, B; Sheng, LS; Luzin, V; Gyula, T
    The hoop, radial and axial stress and strain distribution of surplus assembled 7050Al alloy ring and plus were investigated by neutron diffraction method. The measured results from crystal planes (200) and (311) are coincided with the data obtained by analytical calculation and international standard sample experiment. The discontinuous stress and strain at the interference of ring and plug can be clearly shown by the neutron diffraction method. Monte Carlo method was used to simulate the neutron diffraction process to reduce the deviation of the stress at the surface. The results show that the measured accuracy can be improved when the slits are substituted by the radial collimation. Compared the results obtained from (311) and (200) with analytical calculation, it reveals that the stress distribution among crystal planes will cause system deviation. Therefore the experiment accuracy may be further improved if the inner plane stress could be evaluated. The results also indicate that the strain accuracy will be affected by microstress and texture, and the gauge volume should be reduced as small as possible at the region where the stress distribution is steep. ©2020 Science China Press Co. Ltd.