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In the present research, aluminum expanded mesh grids are considered for negative electrodes in lead-acid batteries. The conventional negative electrodes made from lead alloy grids are replaced by the expanded mesh grids that are made from a commercial aluminum alloy as they are lightweight, have higher conductivity, and are available in bulk. To accomplish this, aluminum grids were considered with their surfaces modified by lead coatings prior to electrode preparation. Hence Al grids find an envious place in lead-acid battery applications. In this study, Al grids were pretreated for surface cleaning followed by Zn coating, electroplating with Cu and hot-dip coating in a molten Pb alloy bath. The surface coated Al grids were analyzed using X-ray diffraction, field emission scanning electron microscopy, and energy dispersive X-ray analysis elemental mapping. Microhardness measurements were made on the prepared specimens. Electrochemical performance tests on 2V batteries at higher discharge rates and life cycles were conducted. The specific energy of batteries with Al grids was 80 W h/kg, which is 20% higher than that of a Pb grid type. By replacing Pb grids with surface modified Al grids in lead-acid batteries, the consumption of lead gets reduced by 5%, resulting in a cost-effective and environment-friendly approach.

Commercial Pure (CP) grade-2 titanium is a choice material for the construction of Silver Oxide Zinc reserve-battery components like battery containers, cell casings, electrolyte bladder housings, etc. The above-said components are either not directly exposed to electrolyte or have limited duration exposure, e.g., the cell-case is filled with electrolyte just before operational use, by transferring the stored electrolyte from the electrolyte tanks, using pressurized gas. There is a need to widen the application CP grade-2 titanium material for the construction of electrolyte tank-reservoir in reserve batteries, where long storage requirement exists. Therefore, a study was undertaken on the corrosion behavior of CP grade-2 titanium material, with the known concentration of Potassium Hydroxide (KOH), as used in reserve battery applications. The samples for the conduct of the experiment were carefully prepared by TIG welding procedure. Material characterization studies were undertaken by macro and microstructural analysis using optical microscope (OM), phase analysis by X-ray diffraction (XRD), and Scanning Electron Microscope (SEM). Further, different corrosion studies like immersion test, salt spray test, potentiodynamic polarization studies, and surface morphology studies were undertaken. The results of all the above studies revealed that CP grade-2 titanium material with weld joints if prepared with the standardized procedure, can be effectively used in the construction of electrolyte tanks for Silver Oxide Zinc based Reserve Batteries for meeting strategic defense applications.

This paper deals with a novel method of forming a score mark to develop silver based metal diaphragm cum rupture disc using laser micro machining technique. Defense oriented primary reserve type si...

In this study, an effective preparation of Pt-WO3-TiO2/C electrocatalysts has been developed for polymer electrolyte membrane fuel cell (PEMFC) application. The single cell performance of Vulcan XC-72R carbon-supported Pt-WO3-TiO2 electrocatalysts with various compositions (as weight percentage Pt-W-Ti 0:5:5, 2:4:4, 4:3:3, 6:2:2, and 8:1:1) as anode materials are investigated in PEMFC. These catalysts are compared with 10 % Pt/C on the same Vulcan XC-72R carbon support and 10 % Pt/C (commercial) electrocatalyst. The physical and morphological characterization of the optimized Pt-WO3-TiO2/C, 10 % Pt/C, and 10 % Pt/C (commercial) electrocatalysts are further investigated by X-ray diffraction (XRD), cyclic voltammetry, scanning electron microscopy with energy-dispersive X-ray analysis, and transmission electron microscopy (TEM) techniques. Among all the molar ratio of the catalysts, the Pt-W-Ti (4:3:3) molar ratio catalyst exhibited the larger electrochemical active surface area. The electrochemical performance of Pt-WO3-TiO2/C (with a weight percentage of Pt-W-Ti 4:3:3) as anode material is better than those of other compositions of Pt-WO3-TiO2/C catalysts. The amount of platinum was also reduced from 1.76 to 0.704 mg cm−2 which exhibited higher performance in single cell tests. Platinum shows a smaller-sized crystalline structure in XRD and TEM analysis. High performance indicates that enhanced proton transport occurs through the use of this catalyst.

Nano-structured Pt–WO 3 /C, Pt–WO 3 –TiO 2 /C and Pt/C catalysts are synthesized by chemical reduction method using sodium borohydride as reducing agent. The catalysts thus prepared are characterized and compared with commercial Pt/C catalyst. The electrochemical performances are characterized by single cell test evaluation, long term stability test and cyclic voltammetry measurement. The chemical compositions, physical and morphological characterizations are investigated by various techniques such X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). XRD analysis shows that, all prepared catalysts exhibited face-centered cubic structures. XRD results confirm that, the Pt–WO 3 /C and Pt–WO 3 –TiO 2 /C catalysts are smaller in particle size and larger in surface area calculated from line broadening. The amount of Pt reduced from1.76 mg cm −2 (10% Pt/C) to 1.056 mg cm −2 and 0.704 mg cm −2 in the case of Pt–WO 3 /C and Pt–WO 3 –TiO 2 /C respectively. Both the tungstate and titanate based electrocatalysts have exhibited higher performance in single cell tests than lone Pt catalysts.