9-13 July 2012
Synthesis and electrochemical properties of cation doped spinel LiMxMn2-xO4 (M=Ni, Al and x=0, 0.5) cathode materials for Li-ion battery
Presented by Dr. Mesfin KEBEDE on 12 Jul 2012 from 11:40 to 12:00
Type: Oral Presentation
Track: Track A - Division for Condensed Matter Physics and Materials
LiMn<sub>2</sub>O<sub>4</sub> spinel is attractive cathode material for rechargeable lithium ion battery (LIB) applications such as portable electronics, hybrid electric vehicles and power tools. LiMn<sub>2</sub>O<sub>4</sub> has got high attention because of its low cost, low toxicity, safety and high voltage compared to that of layered LiCoO<sub>2</sub> commercialized cathode material for LIB. The most known drawback of LiMn<sub>2</sub>O<sub>4</sub> is its capacity fading during repeated charge/discharge cycling. Lithium manganese oxide (LiMn<sub>2</sub>O<sub>4</sub>) and cation-doped Lithium manganese oxide LiM<sub>0.5</sub>Mn<sub>1.5O4</sub> (M=Al, Ni) spinel cathode materials were synthesized using corresponding metal nitrates and urea as starting precursors. The particle size and morphology and the structural and electrochemical properties of the as-synthesized cathode materials were examined by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and charge/discharge cycle battery tester. It was found that the cation doping showed great influence on their electrochemical properties and crystalline structure. The LiM<sub>0.5</sub>Mn<sub>1.5O4</sub> (M=Al, Ni) cathode materials display a spinel structure indicating a small change in peak position due to differences in size between M(Al, Ni) and Mn ions. Partial cation doping of manganese in the host structure by aluminium (Al) and nickel (Ni) ion yielded successful improvements to get stabilized electrode without any rapid capacity loss. The characteristics of stabilizing the discharge capacity by the two samples are compared and the possible mechanisms will be reported.