An energy storage device includes a housing having an interior surface defining a volume and a plurality of solid electrolyte elements disposed in the volume. Each solid electrolyte element has a first surface that defines at least a portion of a first, cathodic chamber, and a second surface that defines a second, anodic chamber. A plurality of individual anodic chambers are thus provided, at least one of which is evacuated below atmospheric pressure. A majority of anodic chambers can be spaced from one another in a manner that provides a substantially uniform reaction rate throughout the cathodic chamber. The housing and the plurality of solid electrolyte elements together may be configured to define a second volume devoid of solid electrolyte elements and that is sufficient in size to accommodate a desired number of solid electrolyte elements and to provide an accessible cathodic chamber filling point and that is further sufficient in size to alter the volume of the cathodic chamber with respect to the volume of the plurality of anodic chambers to achieve a desired volumetric ratio between the cathodic and anodic chambers.