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In order to find the adequate material for Fe/air battery anode，two kinds of materials，Fe_2O_3-nano-loaded carbon and Fe_2O_3-nano mixed carbon material using various carbon materials, were prepared．The Fe_2O_3-nano-loaded carbon material was prepared by loading Fe_2O_3 on carbon using a chemical method．Fe(NO3)3 was impregnated on carbon with different weight ratios of iron to carbon in an aqueous solution，and the mixture was dried and then calcined for 1 h at 400℃ in flowing Ar．For the Fe_2O_3-nano mixed carbon material, Fe_2O_3-nano powder was mixed with carbon by mechanical method. The effect of various carbons on the physical and electrochemical properties of both Fe_2O_3-nano-loaded carbon and Fe_2O_3-nano mixed carbon electrodes was investigated and compared using X-ray diffraction(XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) along with X-ray energy-dispersive spectroscopy(EDS), cyclic voltammetry(CV) and galvanostatic cycling performance．Transmission electron microscopy(TEM) coupled with X-ray diffraction measurements revealed that Fe_2O_3-nanoparticles were distributed on the carbon surface for Fe_2O_3-nano-loaded carbon．This distribution is similar to that for Fe_2O_3-nano mixed carbon electrodes observed by SEM and EDS．The CV results indicated that the redox currents of the Fe_2O_3-nano-loaded carbon are larger than that of correspondence Fe_2O_3-nano mixed carbon．Such properties are expected to provide the larger capacity for Fe_2O_3-nano-loaded carbon electrode than Fe_2O_3-nano mixed carbon electrode.

We synthesized the two pyrophosphates LiVP_2O_7 and TiP_2O_7 by a solid state reaction, and the cathode properties of lithium secondary batteries were investigated. The structures were characterized by powder X-ray Rietveld refinement. Lithium cells using LiVP_2O_7 and TiP_2O_7 cathodes showed that approximately 0.5 Li per unit could be reversibly deintercalated from LiVP_2O_7 at 4.1V vs. Li/Li^+, 0.8 Li per unit could be reversibly intercalated into TiP_2O_7 at 2.6V vs. Li/Li^+. The redox potentials 4.1V of LiVP_2O_7 and 2.6V of TiP_2O_7 were higher than that of transition metal oxides such as VO_2 and TiO_2.

Four types of orthorhombic olivine LiMPO_4 (M:Co, Fe, Ni, Mn) were investigated as high voltage cathode active materials for lithium secondary batteries. LiCoPO_4 exhibited the highest 4.8V discharge plateau of 100mAh/g vs. Li/Li^+ after initial charging to 5.1V and its energy density was comparable to that of layeredrocksalt LiCoO_2 (120mAh/g×4V=480mWh/g). In contrast, the open circuit voltage profile of LiFePO_4 was 160mAh/g on the 3V plateau. TG-DSC measurements showed that the thermal stability of charged Li_CoPO_4 is better than that of fully-charged Li_CoO_2. The chemical state of Co in LiCoPO_4 was also analyzed using HRXRF.

The current-potential relationships for the electrochemical oxidation of organic solvent electrolytes on microelectrodes are confirmed for various lithium salts, namely ${\rm LiClO}_4$, ${\rm LiBF}_4$, ${\rm LiCF}_3{\rm SO}_3$ and ${\rm LiPF}_6$. The oxidation is expected to occur by means of a two stage process; the chemical degradation of the solvent followed by the electrochemical generation of anion radical species, and the direct electrochemical oxidation of the solvent. The dependence of the oxidation current on temperature and the lithium salt concentration confirms this two step reaction feature. In other words, a reaction based on electrochemically generated anion radicals seems to occur below 4.8V vs. Li/Li$^+$ and direct oxidation of the solvent occurs above 4.8V. Above 4.8V, we cannot disregard the distribution of the diffusion-limiting current of the anion radical into the whole oxidation current.