Electrochemical performance of cobalt free, Li1.2(Mn0.32Ni0.32Fe0.16)O2 cathodes for lithium batteries
Lee, G. W.
Kang, K. S.
Kim, W. S.
Lee, Y. S.
Date of Issue2012
Energy Research Institute
Cobalt free, eco-friendly layered Li1.2(Mn0.32Ni0.32Fe0.16)O2 compounds were synthesized using the adipic acid assisted sol–gel method. The structure and morphology of the prepared materials were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD results revealed that all of the materials possess a layered α-NaFeO2 structure with space group. The TEM images confirmed the presence of carbon on the surface of the synthesized material. Galvanostatic charge/discharge studies demonstrated that the cyclic performance and rate capability of the materials were improved by the presence of carbon and the crystalline nature of the material. Among the synthesized materials, the sample prepared with 1 M adipic acid exhibited not only a high discharge capacity of 160 mAh g−1, but also excellent cycling performance with a capacity retention of over 92% after 25 cycles. In addition, electrochemical impedance spectroscopy (EIS) was used to confirm the improvement in the electronic conductivity and the results are discussed in detail.
© 2012 Elsevier. This is the author created version of a work that has been peer reviewed and accepted for publication by Electrochimica Acta , Elsevier. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [DOI: http://dx.doi.org/10.1016/j.electacta.2012.02.076 ]