TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The gas permeable and liquid impermeable membrane: comprises a fluoropolymer material; is positioned downstream along the flow path from the fuel electrode and the oxidant electrode, and configured to vent by permeation gases generated during electrochemical reactions at the fuel and oxidant electrodes; is configured to contact the ionically conductive medium while it flows through the flow path; is positioned down the flow path from the fuel electrode and the oxidant electrode, and configured to receive gases generated during electrochemical reactions at the fuel and oxidant electrodes; comprises the oxidant electrode; and is configured to prevent permeation of the ionically conductive medium out of the housing, but permit gas in the housing to permeate through it for venting of the gas from the electrochemical cells. The fluoropolymer material comprises PTFE. The liquid ionically conductive medium is configured to flow in a flow path through and among the electrochemical cells. The housing comprises a cell module configured to receive the fuel electrode, and at least one sidewall configured to receive the oxidant electrode and the gas permeable and liquid impermeable membrane, where the sidewall is assembled onto the cell module to constrain the ionically conductive medium to the flow path. In the electrochemical cell system: a portion of the gas permeable and liquid impermeable membrane comprises the oxidant electrode; each electrochemical cell further comprises a charging electrode comprising the oxidant electrode, a separate charging electrode spaced from the fuel and oxidant electrodes, and a portion of the fuel electrode; and each electrochemical cell is associated with the housing. The fuel electrode and the charging electrode are configured to, during re-charge, reduce a reducible species of the metal fuel to electrodeposit the metal fuel on the fuel electrode and oxidize an oxidizable species of the oxidant by application of a re-charge potential difference between them from a power source. The fuel electrode comprises a series of permeable electrode bodies arranged in spaced apart relation, where the spaced apart relation of the permeable electrode bodies enables the re-charge potential difference to be applied between the charging electrode and at least one of the permeable electrode bodies, with the charging electrode functioning as the anode and the permeable electrode body functioning as the cathode, so that the reducible fuel species are reduced and electrodeposited as the metal fuel in oxidizable form on the permeable electrode body, where the electrodeposition causes growth of the metal fuel among the permeable electrode bodies so that the electrodeposited metal fuel establishes an electrical connection between the permeable electrode bodies. The ionically conductive medium comprises an aqueous electrolyte solution. The cell module contains a flow path for the liquid ionically conductive medium in it, where the flow path is configured to facilitate a flow of the ionically conductive medium through the electrochemical cell system. Preferred Method: The method further comprises providing a charging electrode comprising the oxidant electrode, a separate charging electrode spaced from the fuel and oxidant electrodes, and a portion of the fuel electrode.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The reducible species of the metal fuel comprises ions of zinc, iron, aluminum, magnesium, or lithium, where the metal fuel is zinc, iron, aluminum, magnesium, or lithium. The aqueous electrolyte solution comprises sulfuric acid, phosphoric acid, triflic acid, nitric acid, potassium hydroxide, sodium hydroxide, sodium chloride, potassium nitrate, or lithium chloride.