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Abstract: The deposition of corrosion products of MmNi3.55Co0.75Al0.2Mn0.5 alloy in the positive electrodes of nickel-metal-hydride (Ni-MH) battery is tested by using inductively coupled plasma spectroscopy. The deposition amounts of Al and Mn are markedly reduced by using an acrylic acid (AA) grafted polypropylene (PP) separator. The detrimental effect of Mn on self-discharge performance of Ni-MH battery is indirectly demonstrated by using nickel-cadmium (Ni-Cd) battery with a deliberate addition of Mn element into the KOH electrolyte. The shuttle reactions between Mn(III) and Mn(II) in the electrolyte are confirmed by cyclic voltammetry tests. Based on these results, a possible mechanism of AA grafted PP separator is proposed that it can trap Mn ion in the electrolyte, thus suppressing the detrimental shuttle reactions, and thereby reducing the self-discharge rate of the batteries. [Copyright &y& Elsevier]

Pt decorated RuFeSe/C catalyst is prepared by reduction of Pt precursor on pre-formed RuFeSe/C for oxygen reduction reaction (ORR). The catalyst is characterized by X-ray diffraction (XRD), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The catalyst particles are found to disperse on the carbon support with an average particle size of 2.8 nm. Physical characterizations and electrochemical tests confirm that Pt is deposited on the surfaces of RuFeSe particles and RuFeSe@Pt/C catalyst has a core-shell structure. The as-prepared catalyst has high durability and shows high ORR activity through a four-electron transfer process. RuFeSe@Pt/C exhibits 1.3-fold greater specific activity and 1.4-fold greater mass activity for ORR than Pt/C. More importantly, it has excellent tolerance to methanol. Consequently, RuFeSe@Pt/C may be used as fine cathode catalyst in direct methanol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

Abstract: The electrode is the key part of the electrochemical capacitors (ECs), so the electrode materials are the most important factors to determine the properties of ECs. In this paper, the storage principles and characteristics of electrode materials, including carbon-based materials, transition metal oxides and conductive polymers for ECs are depicted briefly. Among them, more work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and organic electrolytes. But the composites of pseudocapacitive and carbonaceous materials are promising electrode materials for ECs because of their good electrical conductivity, low cost and high mass density. [Copyright &y& Elsevier]

Abstract: Nanocrystalline NiO was synthesized by high temperature solid-state (HTSS) method and microwave (MW) method. The structure of the samples was examined by X-ray. Electrochemical properties were examined by galvanostatic charge–discharge measurements, cyclic voltammetry and electrical impedance spectroscopy. The results showed that the particle sizes of the NiO prepared by MW and HTSS were 34.6 and 75.5nm. The specific capacitance of MW and HTSS were 186 and 97Fg−1, which decreased to 170 and 74Fg−1 after 1000 cycles. It revealed that the NiO materials prepared by MW exhibited good specific capacitance and cycling performance, which had the high surface redox reactivity due to its special nanostructures. [Copyright &y& Elsevier]

Abstract: Nanosized Mg0.8Cu0.2O powders were prepared by sol–gel method. In order to improve the electrochemical performances of Li/S rechargeable batteries, Mg0.8Cu0.2O was used as an additive for crystalline vanadium pentoxide (c-V2O5)/S composite cathode. The composite electrodes with and without additive were characterized by scanning electron microscopy, galvanostatic charge–discharge, rate capability and cycle performance. The results showed that not only the cycle life and discharge capacity were improved, but also the rate capability was improved after the addition of Mg0.8Cu0.2O. The improvements of electrochemical performances were due to the adsorbing effect on polysulfide of Mg0.8Cu0.2O. Furthermore, the additive also had catalytic effect on promoting redox reaction of the Li/S batteries. [Copyright &y& Elsevier]