Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9760477 | Journal of Power Sources | 2005 | 6 Pages |
Abstract
A comparative analysis of the properties of LiNi0.5Mn0.5O2 and Li1+xNi0.5Mn0.5O2 (0.2 ⤠x ⤠0.7) powders, obtained by the freeze drying method, was performed. Lattice parameters of Li1+xNi0.5Mn0.5O2 decreased considerably with growing amounts of Li until x = 0.3; at x > 0.5 trace amounts of Li2MnO3 are observed by X-ray diffraction (XRD) patterns. X-ray photoelectron spectroscopy (XPS) analysis displayed an increase of Ni3+/Ni2+ ratio at 0.3 < x < 0.5, while Mn 2p spectra were almost identical in all samples. Rechargeable capacity values (V = 2.5-4.6 V) increased systematically with x reaching its maximum (185-190 mAh gâ1) at x = 0.5. Samples with superstoichiometric lithium content also demonstrated good C rate characteristics.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Sun Hee Choi, O.A. Shlyakhtin, Joosun Kim, Young Soo Yoon,