Abstract: A method and system for storing and/or discharging electrical energy that has a cost, which method includes steps of: (a) providing a flow battery system comprising at least one flow battery cell and a controller; (b) operating the flow battery cell at a power density having a first value; and (c) changing the power density at which the flow battery cell is operated from the first value to a second value as a function of the cost of the electrical energy, wherein the power density is changed using the controller, and wherein the second value is different than the first value.

Abstract: A flow battery stack includes a plurality of flow battery cells, a manifold and a heat exchanger. Each flow battery cell includes an electrode layer that is wet by an electrolyte solution having a reversible redox couple reactant. The manifold includes a solution passage that exchanges the electrolyte solution with the flow battery cells. The heat exchanger includes a heat exchange fluid passage. The heat exchanger exchanges heat between the electrolyte solution in the solution passage and a heat exchange fluid directed through the heat exchange fluid passage. The flow battery cells, the manifold and the heat exchanger are arranged between first and second ends of the flow battery stack.

Abstract: A flow battery includes an electrode operable to be wet by a solution having a reversible redox couple reactant. In one embodiment, the electrode can have plurality of micro and macro pores, wherein the macro pores have a size at least one order of magnitude greater than a size of the micro pores. In another embodiment, the electrode includes a plurality of layers, wherein one of the plurality of layers has a plurality of macro pores, and wherein another one of the plurality of layers has a plurality of micro pores. In another embodiment, the electrode has a thickness less than approximately 2 mm. In still another embodiment, the electrode has a porous carbon layer, wherein the layer is formed of a plurality of particles bound together.

Abstract: A method is provided for mitigating hydrogen evolution within a flow battery system that includes a plurality of flow battery cells, a power converter and an electrochemical cell. The method includes providing hydrogen generated by the hydrogen evolution within the flow battery system to the electrochemical cell. A first electrical current generated by an electrochemical reaction between the hydrogen and a reactant is sensed, and the sensed current is used to control an exchange of electrical power between the flow battery cells and the power converter.

Abstract: A flow battery system includes an ON mode, and OFF mode and a STANDBY mode. The ON mode enables access to a full energy capacity of the flow battery system with regard to an amount of electric power that can be drawn from or stored to the flow battery system. The OFF mode disables access to the full energy capacity and the STANDBY mode enables access to a portion of the full energy capacity.

Abstract: A flow battery includes an electrode operable to be wet by a solution having a reversible redox couple reactant. In one embodiment, the electrode can have plurality of micro and macro pores, wherein the macro pores have a size at least one order of magnitude greater than a size of the micro pores. In another embodiment, the electrode includes a plurality of layers, wherein one of the plurality of layers has a plurality of macro pores, and wherein another one of the plurality of layers has a plurality of micro pores. In another embodiment, the electrode has a thickness less than approximately 2 mm. In still another embodiment, the electrode has a porous carbon layer, wherein the layer is formed of a plurality of particles bound together.

Abstract: A flow battery includes a liquid electrolyte that has an electrochemically active specie and a bipolar plate that has channels for receiving flow of the liquid electrolyte. A porous electrode is arranged immediately adjacent the bipolar plate. The porous electrode is catalytically active with regard to the liquid electrolyte. The channels of the bipolar plate have at least one of a channel arrangement or a channel shape that is configured to positively force at least a portion of the flow of the liquid electrolyte into the porous electrode.

Abstract: A flow battery includes an electrode operable to be wet by a solution having a reversible redox couple reactant. In one embodiment, the electrode can have plurality of micro and macro pores, wherein the macro pores have a size at least one order of magnitude greater than a size of the micro pores. In another embodiment, the electrode includes a plurality of layers, wherein one of the plurality of layers has a plurality of macro pores, and wherein another one of the plurality of layers has a plurality of micro pores. In another embodiment, the electrode has a thickness less than approximately 2 mm. In still another embodiment, the electrode has a porous carbon layer, wherein the layer is formed of a plurality of particles bound together.

Abstract: A fuel cell device includes a plurality of channels that have at least one unrestricted inlet, a conduit for directing a flow having a distribution pattern to the unrestricted inlet, and a gap region between the conduit and the plurality of channels for receiving the flow distribution pattern, the gap region having such dimensions in which the distribution pattern tends to normalize within the gap region so that flow to each of the unrestricted inlets tends to normalize across said gap region.

Abstract: A method and system for storing and/or discharging electrical energy that has a cost, which method includes steps of: (a) providing a flow battery system comprising at least one flow battery cell and a controller; (b) operating the flow battery cell at a power density having a first value; and (c) changing the power density at which the flow battery cell is operated from the first value to a second value as a function of the cost of the electrical energy, wherein the power density is changed using the controller, and wherein the second value is different than the first value.

Abstract: A method and system for storing and/or discharging electrical energy that has a cost, which method includes steps of: (a) providing a flow battery system comprising at least one flow battery cell and a controller; (b) operating the flow battery cell at a power density having a first value; and (c) changing the power density at which the flow battery cell is operated from the first value to a second value as a function of the cost of the electrical energy, wherein the power density is changed using the controller, and wherein the second value is different than the first value.

Abstract: A method is provided for mitigating hydrogen evolution within a flow battery system that includes a plurality of flow battery cells, a power converter and an electrochemical cell. The method includes providing hydrogen generated by the hydrogen evolution within the flow battery system to the electrochemical cell. A first electrical current generated by an electrochemical reaction between the hydrogen and a reactant is sensed, and the sensed current is used to control an exchange of electrical power between the flow battery cells and the power converter.

Abstract: A method is provided for mitigating hydrogen evolution within a flow battery system that includes a plurality of flow battery cells, a power converter and an electrochemical cell. The method includes providing hydrogen generated by the hydrogen evolution within the flow battery system to the electrochemical cell. A first electrical current generated by an electrochemical reaction between the hydrogen and a reactant is sensed, and the sensed current is used to control an exchange of electrical power between the flow battery cells and the power converter.

Abstract: A flow battery system includes an ON mode, and OFF mode and a STANDBY mode. The ON mode enables access to a full energy capacity of the flow battery system with regard to an amount of electric power that can be drawn from or stored to the flow battery system. The OFF mode disables access to the full energy capacity and the STANDBY mode enables access to a portion of the full energy capacity.

Abstract: A flow battery stack includes a plurality of flow battery cells, a manifold and a heat exchanger. Each flow battery cell includes an electrode layer that is wet by an electrolyte solution having a reversible redox couple reactant. The manifold includes a solution passage that exchanges the electrolyte solution with the flow battery cells. The heat exchanger includes a heat exchange fluid passage. The heat exchanger exchanges heat between the electrolyte solution in the solution passage and a heat exchange fluid directed through the heat exchange fluid passage. The flow battery cells, the manifold and the heat exchanger are arranged between first and second ends of the flow battery stack.

Abstract: A flow battery stack includes an inlet manifold, an outlet manifold and a plurality of flow battery cells. The inlet and outlet manifolds each have first and second passages. The first and second passages in at least one of the inlet and outlet manifolds are tortuous. Each flow battery cell includes a separator arranged between a first electrode layer and a second electrode layer. The flow battery cells are axially connected between the inlet manifold and the outlet manifold such that a first solution having a first reversible redox couple reactant is directed from the inlet first passage through the flow battery cells, wetting the first electrode layers, to the outlet first passage.

Abstract: A fuel cell (10) device includes a plurality of channels (32, 34) that have at least one unrestricted inlet (33), a conduit for directing a flow having a distribution pattern (84) to the unrestricted inlet (33) and an opening (40) between the conduit (50) and the opening (40) for receiving the flow distribution pattern (84), the opening having such dimension (L, W) in which the distribution pattern tends to normalize within the opening so that flow to each of the unrestricted inlet (33) tends to normalize across said opening.

Abstract: A method is provided for mitigating hydrogen evolution within a flow battery system that includes a plurality of flow battery cells, a power converter and an electrochemical cell. The method includes providing hydrogen generated by the hydrogen evolution within the flow battery system to the electrochemical cell. A first electrical current generated by an electrochemical reaction between the hydrogen and a reactant is sensed, and the sensed current is used to control an exchange of electrical power between the flow battery cells and the power converter.

Abstract: A flow battery includes an electrode operable to be wet by a solution having a reversible redox couple reactant. In one embodiment, the electrode can have plurality of micro and macro pores, wherein the macro pores have a size at least one order of magnitude greater than a size of the micro pores. In another embodiment, the electrode includes a plurality of layers, wherein one of the plurality of layers has a plurality of macro pores, and wherein another one of the plurality of layers has a plurality of micro pores. In another embodiment, the electrode has a thickness less than approximately 2 mm. In still another embodiment, the electrode has a porous carbon layer, wherein the layer is formed of a plurality of particles bound together.

Abstract: A flow battery includes a membrane having a thickness of less than approximately one hundred twenty five micrometers; and a solution having a reversible redox couple reactant, wherein the solution wets the membrane.