FORM ENERGY, INC.

An electrochemical cell includes a mist elimination system that prevents mist from escaping from the cell chamber and conserves moisture within the cell. An exemplary mist elimination system includes a spill prevention device that reduces or prevents an electrolyte from escaping from the cell chamber in the event of an upset, wherein the electrochemical cell is tipped over. A mist elimination system includes a recombination portion that reacts with hydrogen to produce water, that may be reintroduced into the cell chamber. A mist elimination system includes a neutralizer portion that reacts with an electrolyte to bring the pH closer to neutral, as acid/base reaction. A mist elimination system includes a filter that captures mist that may be reintroduced into the cell chamber. A mist elimination system includes a hydrophobic filter on the outer surface to prevent water and other liquids from entering into the mist elimination system.

Electrochemical metal-air cells having nested electrodes provided in an annular or cylindrical configuration, including systems that contain such cells in a sealed container. Each cell may include an oxidant electrode (air cathode) and a fuel electrode (anode), both configured in annular form. A series of permeable bodies, screens, or current collectors may be provided as part of the fuel electrode. An annular oxygen evolution electrode may also be provided in the cells. In some cases, the fuel electrode is nested within the oxidant electrode, or vice versa. Optionally, a second oxidant electrode may be included in the cells. Ionically conductive medium or electrolyte may be contained in the cell. Each cell may have its own cell housing. Optionally, an air space or pocket may be formed in a cell via an oxidant electrode. The sealed container may contain the cells such that they are surrounded by air or an electrolyte.

An exemplary electrochemical cell incorporates at least a first battery electrode, such as a zinc electrode, at least a second battery electrode, such as a reversible metal electrode such as nickel, and at least an oxidant reduction electrode, such as an air cathode. The oxidant reduction electrode(s) is configured in a cell housing such that it is essentially orthogonal to the first and second electrodes. The cell housing contains electrolyte therein and the electrodes are immersed, at least partially, in the electrolyte. The positioning of the oxidant reduction electrode(s) on the side of the cell and relatively perpendicular to the first and second (metal) electrodes, allows for more consistent ionic resistance across all the metal electrodes. Optionally, a fourth or oxygen evolving electrode may be provided in the cell housing, horizontal, orthogonal, and below the first and second electrodes to provide oxygen bubbles for mixing the electrolyte.

An electrochemical cell includes a mist elimination system that prevents mist from escaping from the cell chamber and conserves moisture within the cell. An exemplary mist elimination system includes a spill prevention device that reduces or prevents an electrolyte from escaping from the cell chamber in the event of an upset, wherein the electrochemical cell is tipped over. A mist elimination system includes a recombination portion that reacts with hydrogen to produce water, that may be reintroduced into the cell chamber. A mist elimination system includes a neutralizer portion that reacts with an electrolyte to bring the pH closer to neutral, as acid/base reaction. A mist elimination system includes a filter that captures mist that may be reintroduced into the cell chamber. A mist elimination system includes a hydrophobic filter on the outer surface to prevent water and other liquids from entering into the mist elimination system.

Systems and methods of the various embodiments may provide porous materials for electrodes of electrochemical energy storage systems.

An electrochemical cell utilizes an air flow device that draws air through the cell from a scrubber that may be removed while the system is operating. The negative pressure generated by the air flow device allows ambient air to enter the cell housing when the scrubber is removed, thereby enabling continued operation without the scrubber. A moisture management system passes outflow air from the cell through a humidity exchange module that transfers moisture to the air inflow, thereby increasing the humidity of the air inflow. A recirculation feature comprising a valve allow a controller to recirculate at least a portion of the outflow air back into the inflow air. The system may comprise an inflow bypass conduit and valve that allows the humidified inflow air to pass into the cell inlet without passing through the scrubber. The scrubber may contain reversible or irreversible scrubber media.

An electrochemical cell utilizes an air flow device that draws air through the cell from a scrubber that may be removed while the system is operating. The negative pressure generated by the air flow device allows ambient air to enter the cell housing when the scrubber is removed, thereby enabling continued operation without the scrubber. A moisture management system passes outflow air from the cell through a humidity exchange module that transfers moisture to the air inflow, thereby increasing the humidity of the air inflow. A recirculation feature comprising a valve allow a controller to recirculate at least a portion of the outflow air back into the inflow air. The system may comprise an inflow bypass conduit and valve that allows the humidified inflow air to pass into the cell inlet without passing through the scrubber. The scrubber may contain reversible or irreversible scrubber media.

An electrochemical cell includes a permeable fuel electrode configured to support a metal fuel thereon, and an oxidant reduction electrode spaced from the fuel electrode. An ionically conductive medium is provided for conducting ions between the fuel and oxidant reduction electrodes, to support electrochemical reactions at the fuel and oxidant reduction electrodes. A charging electrode is also included, selected from the group consisting of (a) the oxidant reduction electrode, (b) a separate charging electrode spaced from the fuel and oxidant reduction electrodes, and (c) a portion of the permeable fuel electrode. The charging electrode is configured to evolve gaseous oxygen bubbles that generate a flow of the ionically conductive medium. One or more flow diverters are also provided in the electrochemical cell, and configured to direct the flow of the ionically conductive medium at least partially through the permeable fuel electrode.