Miniature electrochemical cell having a casing comprising opposed ceramic substrates housing an electrode assembly activated with a solid electrolyte

A miniature electrochemical cell having a volume of less than 0.5 cc is described. The cell has a casing of first and second ceramic substrates that are hermetically secured to each other to provide an internal space housing an electrode assembly. First and second conductive pathways extend through the ceramic substrates. The pathways have respective inner surfaces that are conductively connected to the respective anode and cathode current collectors and respective outer surfaces that provide for connection to a load. An electrolyte in the internal space of the housing activates the electrode assembly.