Alkaline gel electrolyte for electrochemical cells

摘要

An alkaline gel electrolyte for an electrochemical cell is based on a polymeric binder of polyvinyl alcohol or polyvinyl acetate. Potassium hydroxide and/or sodium hydroxide is blended into the polymeric binder or matrix, and the resulting solution is used to cast a film that is useful as a gel electrolyte. The hydroxide in the solution is between about 1% to 25% by weight, and the polymer concentration is between about 0.5% to 10% by weight. The resulting gel electrolyte film contains between 10 to 90% water by weight. A nickel or iron porphine modifier may be added in an amount between about 1 to 1000 parts per million. The alkaline gel electrolyte is useful in combination with asymmetric inorganic electrodes to make electrochemical cells, and can also function as a separator. Improved power density and higher cycle life is achieved with the gel electrolyte.