Redox flow battery arrays and methods for state of charge balancing
AssigneeInvinity Energy Systems (Canada) Corporation
InventorsAndrew Klassen, David Genders, Matthew Harper
Life of this patent
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Abstract
Designs of redox flow battery arrays and methods for balancing state of charge within the arrays are disclosed. Flow battery unit strings in the arrays which comprise strings of flow battery units (in which units share a common electrolyte pair) are balanced by measuring the states of charge of the common electrolyte pairs and appropriately regulating flow in one or more of the associated anolyte and catholyte circuits so as to balance the state-of charge in the flow battery unit strings. The apparatus required, i.e. state-of-charge measuring device, flow regulator, and controller, represents a substantial simplification to state of the art approaches.
Claims21
A redox flow battery array comprising:
- at least two flow battery unit strings electrically connected in parallel wherein each flow battery unit string comprises at least one flow battery unit comprising:
- a flow battery string comprising at least one flow battery cell wherein each cell comprises an anode and a cathode, and is configured to receive flow battery unit electrolytes comprising an anolyte and a catholyte;
- an anolyte tank and a catholyte tank for storage of the anolyte and the catholyte of the flow battery unit electrolytes respectively;
- an anolyte circuit comprising a supply line and a return line connecting the anolyte tank to the anodes in flow battery cells in the flow battery string;
- a catholyte circuit comprising a supply line and a return line connecting the catholyte tank to cathodes in the flow battery cells in the flow battery string;
- and
- a state-of-charge measuring device capable of measuring the state of charge of the flow battery unit electrolytes in the flow battery unit;
- a flow regulator in at least one of the anolyte and the catholyte circuits for regulating flow of at least one of the anolyte and the catholyte therethrough in at least one of the flow battery units in the at least two flow battery unit strings;
- a controllable bi-directional power converter electrically connected to each of the at least two flow battery unit strings;
- and
- a controller with inputs connected to each of the state-of-charge measuring devices in the flow battery units and with an output connected to the flow regulator wherein the output of the controller controls the flow regulator so as to regulate the flow of at least one of the anolyte and the catholyte to the anodes and the cathodes in the flow battery cells in the flow battery string in accordance with the states of charge of the flow battery unit electrolytes in the flow battery units and thereby balance the state-of charge in the at least two flow battery unit strings.
Dependencies are inferred from the claim text.