Solution phase catholyte semi-fuel cells (SFC's) are being developed for undersea vehicles power and propulsion applications. Laboratory optimization methods for performance evaluation of SFC's are described. The semi-fuel cell studied was analuminum anode, a solution phase hydrogen peroxide (H{sub}2O{sub}2) catholyte and a silver catalyst. The overall cell reaction was:2A1 + 3HO{sub}2{sup}- + 2OH{sup}- → 2AlO{sub}2{sup}- + OH{sup}- + H{sub}2OThe performance of the semi4uel cell was principally dependent on six parameters: the anode material, the catholyte concentration, the temperature, the electrolyte flow rate, the electrolyte concentration and the current density. Optimization of theparameters was critical to maximizing the power and efficiency of the cell and to minimizing evolution of H{sub}2(g) via an aluminum corrosion reaction:Al + 2H{sub}2O + 2OH{sup}- → 2AlO{sub}2 + 3H{sub}2(g)and evolution of O{sub}2(g) by direct decomposition of H{sub}2O{sub}2: 2H{sub}2O{sub}2→ O{sub}2(g) + 2H{sub}2OOptimization of the semi-fuel cell for six parameters by conventional methodology of changing one variable at a time while keeping all others constant, would require 720 experiments. The Taguchi Method using a statistical orthogonal array to optimize thesix parameters by way of an eighteen experiment matrix are described. Strong correlation between optimum performance and the parameter levels predicted by the Taguchi Method was obtained. Using the Taguchi optimized parameter conditions, a specific energy density of 818 wh/kg was obtained for the Al-H{sub}2O{sub}2 semi fuel-cell. This value represents a 7% increase over the maximum value of 767Wh/kg obtained in the orthogonal array.
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