Abstract
Co, Mn and Mg co-doped lithium nickel oxides of the nominal composition LiNi0.9Co0.1-x[Mn1/2Mg1/2] xO2 (x = 0.00, 0.02, 0.04, 0.06) are synthesized by a co-precipitation technique and solid state route. XPS results reveal that the oxidation states of Ni, Co, Mn and Mg are +3, +3, +4 and +2, respectively. An ordered α-NaFeO2 rock salt structure with R-3̄m symmetry has been confirmed by XRD. The cation mixing of Li/Ni and occupation of Mg ions have been analyzed by Rieveld refinement. Mg ions distribute between 3b and 3a sites in the crystal. Meanwhile a substantial reduction of cation mixing of Li-Ni has been confirmed by Mn-Mg substitution. Better cycling performance is observed in the compound with high Mn-Mg content compared with LiNi 0.9Co0.1O2. Mn-Mg substitution for Co has been shown to suppress the increase of the cell impedance during cycles effectively.
Original language | English |
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Pages (from-to) | 350-357 |
Number of pages | 8 |
Journal | Electrochimica Acta |
Volume | 90 |
DOIs | |
Publication status | Published - 15 Feb 2013 |
Externally published | Yes |
Keywords
- Co, Mn and Mg multi-doping
- Electrochemical study
- Ni-based layered cathode
- Structural study
ASJC Scopus subject areas
- General Chemical Engineering
- Electrochemistry