Amorphous vanadium oxide/carbon composite (V2O5/C) was first applied to the positive electrode active material for rechargeable aluminum batteries. Electrochemical properties of V2O5/C were investigated by cyclic voltammetry and charge-discharge tests. Reversible reduction/oxidation peaks were observed for the V2O5/C electrode and the rechargeable aluminum cell showed the maximum discharge capacity over 200 mAh g(-1) in the first discharging. The XPS analyses after discharging and the following charging exhibited that the redox of vanadium ion in the V2O5/C active material occurred during discharging and charging, and the average valence of V changed between 4.14 and 4.85.

Aluminum bis(trifluoromethanesulfonyl)imide (Al(TFSI) 3 ) was synthesized by a simple substitution reaction and investigated as the Al 3+ source for the electrolyte of a rechargeable Al battery. The electrochemical window was extended to 3.6 V with the electrolyte containing Al(TFSI) 3 in AN, whereas it was ∼2.5 V with the conventional electrolyte for the Al rechargeable battery. A reversible electrochemical Al deposition/dissolution reaction was observed on a Mo plate electrode with small overpotential less than 0.5 V. NMR and Raman spectra identified the main Al species in the electrolyte as Al(TFSI − ) x (AN) 6-x 3-x (x = 1 ∼ 6).

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Charge transfer kinetics at the Li metal electrode/electrolyte interface for three inorganic solid electrolytes and an organic liquid electrolyte were elucidated with two parameters, exchange current density (i 0 ) for Li/Li + couple reactions and ionic conductivity in electrolyte. The former was evaluated by potential step method with a microelectrode, while the latter was done by electrochemical impedance spectroscopy. Both i 0 and ionic conductivity showed Arrhenius type dependence, and activation energies (E a ) for the charge transfer reactions and ionic conduction were evaluated. In the case of the organic liquid electrolyte, E a for the Li/Li + couple reactions was higher than that for ionic conduction because of the solvation/desolvation of Li + ion. However, for the Li 2 S-P 2 S 5 solid solid electrolytes, the E a for the Li/Li + couple reactions was quite close to that for ionic conduction due to the lack of the solvation/desolvation.

In this report, we established a new electrochemical method for the detection of conformational changes in large, non-metalloproteins such as bovine serum albumin, using flow injection analysis coupled with hydrogen-terminated, boron-doped diamond electrodes. The oxidation current was used as a signal reporter in the monitoring of urea-induced BSA denaturation. In the denatured state at high urea concentrations, the electrochemical signal increased, and the amperometric responses for the oxidation potential at 1300 mV were consistent with the results of conventional methods of denaturation monitoring using fluorescence spectroscopy. The oxidation involved at least five redox-active species (cysteine, tryptophan, tyrosine, methionine, and disulfide bonds). Furthermore, the method also showed high sensitivity for quantitative analysis of protein. A linear dynamic in the concentration range 50-400 microg/mL (r(2) = 0.977) with a lower detection limit of 190 ng/mL was achieved for BSA. Direct electrochemical detection of conformation changes of proteins using BDD electrodes can be performed with advantages in terms of simplicity and sensitivity.

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