Electrochemical modification of spinel oxide materials using lithium solid state electrolyte

Characterization of The Lithium−Manganese Ferrite LiFeMnO4 Prepared by Two Different Methods

“…1,23 This discrepancy could be linked to differences in the Mn 3+ /Mn 4+ ratio (see the XPS and Mn K-edge XANES results) and to variations in the concentration of oxygen vacancies. 15 We will return to this result later.…”

“…5,16 It is well known that the intensity of the 220 reflection, which is usually observed in the powder XRD pattern of spinels, depends upon the atomic scattering factors of the ions occupying tetrahedral 8a sites; 13,[22][23][24]34 thus, the 220 peak vanishes in the XRD pattern of LiMn 2 O 4 because, in this structure, the A positions are exclusively occupied by light lithium atoms. 15,21,24 Consequently, the presence of the 220 peak in the diffractogram (see the Supporting Information) indicates that, in both samples, a certain amount of Fe 3+ ions is located at the A sites with a nearly similar occupation (relative intensity of the 220 reflection is 23.6% and 25.8% for Cer and NTD, respectively).…”

“…7 The fraction of Fe 3+ occupying A sites in the compounds Li 0.5 FeMn 1.5 O 4 and LiFe 0.6 -Mn 1.4 O 4 is approximately 40% and 9%, respectively, 7,8 whereas in LiFe 0.5 Mn 1.5 O 4 , only Li + ions occupy the A sites. 4 X-ray powder diffraction (XRD), 1,2,4-17,20-24 57 Fe-Mo ¨ssbauer spectroscopy, 1,4,5,8,[10][11][12]14,15,25 X-ray photoelectron spectroscopy (XPS), 10,12,21,[26][27][28][29][30] and Mn K-edge and Fe K-edge XANES/ EXAFS, 4,12,14 among others, appear to be adequate techniques for determining structural, magnetic, and oxidation state changes in this type of compound and have been largely used.…”

“…Among transition metals, iron is a good candidate for such a replacement due to its abundance and the favorable electrochemical properties of the resulting frameworks. − The electrochemical and magnetic properties of each single phase belonging to the Li−Fe−Mn−O system are connected not only with the range of its Li−Mn−Fe composition but also with both the cationic distribution in the spinel lattice and the Mn and Fe oxidation states. The oxidation states of the ions, their distribution over the tetrahedral (A) and octahedral (B) sublattices, and the electrochemical behavior of the host thermodynamically stable spinels have been extensively studied. − …”

Fabrication and electrochemical properties of lithium-ion batteries for power tools

“…During the last decade, there has been a growing interest in lithium insertion materials, largely because they potentially have a wide range of applications as positive and/or negative electrodes in lithium-ion batteries [1]. Especially, high power batteries for power tools possess more attraction recently for their high rate capability.…”