Development of positive electrodes with an SnO2 coating by applying a sputtering technique for lead-acid batteries

A Low-Cost, High Energy-Density Lead/Acid Battery

“…In the literature are reports [3][4][5][6][7][8][9][10][11][12][13][14][15] of several efforts expended to enhance the energy density of lead/acid batteries primarily by employing lightweight grid materials. Hammar and Harvey 3 reported a lead/acid battery in which the grids comprise a substrate made of a polymer, such as polyvinylchloride, laminated with a thin lead/lead alloy foil.…”

“…In particular, the formation of a tin oxide layer by the simple and convenient dip coating method requires calcinations at a temperature in the range 450-600°C. Accordingly, Kurisawa et al 8 have suggested that it is impossible to apply the dip coating method to a lead substrate, appearing to imply that the calcination temperature required to form the protective tin oxide layer by this method is incompatible with the lead/lead alloy grids.…”

“…Kurisawa et al 9 have therefore attempted to use coating technologies that employ low substrate temperatures, such as vacuumbased thin-film technology, to form protective SnO 2 coatings on lead grids. Kurisawa et al 9 report using the radio-frequency ͑rf͒ sputtering technique to deposit a 15 m thick SnO 2 coating on a 500 m thick lead plate.…”

“…Kurisawa et al 9 report using the radio-frequency ͑rf͒ sputtering technique to deposit a 15 m thick SnO 2 coating on a 500 m thick lead plate. But sputtering is generally a slow process, which may require that the substrate, along with the lead/lead alloy coating, be subjected to ambient temperatures (ϳ120°C) for many hours, potentially compromising the mechanical integrity of the grids.…”

A low-cost lead-acid battery with high specific-energy

“…Recently, Kurisawa et al 6 have attempted to use the radio-frequency sputtering technique to form protective tin oxide coating on lead grids. However, sputtering is generally a slow process, and since it happens to be a line-of-sight process, both sides of the grids cannot be coated simultaneously, unless a complex and expensive sputtering apparatus is employed.…”