Abstract: Methods and systems are provided for a redox flow battery system. In one example, the redox flow battery system includes a cell stack compressed between terminal structures defining ends of the redox flow battery. The cell stack may be formed of a plurality of cells where each cell includes a deformable positive electrode in contact with a first face of a membrane separator and a negative electrode configured to be less compressible than the positive electrode and arranged at a second face of the membrane separator.

Abstract: A redox flow battery and battery system are provided. In one example, the redox flow battery includes a cell stack assembly interposed by two endplates and comprising a plurality of mated membrane frame plates and bipolar frame plates forming, at a mated interface, a plurality of negative and positive flow channels configured to distribute negative and positive electrolyte into a plurality of bipolar plates. In the battery a membrane is coupled to each of the plurality of membrane frame plates and positioned sequentially between two of the bipolar plates included in the plurality of bipolar plates.

Abstract: Systems and methods for operating an electric energy storage device are described. The systems and methods may generate a state of charge estimate that is based on negative electrode plating. An overall state of charge may be determined from the state of charge estimate that is based on negative electrode plating and a state of charge estimate that is not based on negative electrode plating.

Abstract: Systems and methods for operating an electric energy storage device are described. The systems and methods may generate a state of charge estimate that is based on negative electrode plating. An overall state of charge may be determined from the state of charge estimate that is based on negative electrode plating and a state of charge estimate that is not based on negative electrode plating.

Abstract: A method of operating a redox flow battery, may include maintaining a positive electrode compartment pressure greater than a negative electrode compartment pressure, and maintaining a cross-over pressure less than a membrane break-through pressure, wherein the cross-over pressure equals the negative electrode compartment pressure subtracted from the positive electrode compartment pressure. In this way, ionic resistance across the separator can be maintained at a lower level by reducing gas bubbles trapped therein while reducing separator break-through, thereby increasing performance of the redox flow battery system.

Abstract: Systems and methods for operating an electric energy storage device are described. The systems and methods may generate a state of charge estimate that is based on negative electrode plating. An overall state of charge may be determined from the state of charge estimate that is based on negative electrode plating and a state of charge estimate that is not based on negative electrode plating.

Abstract: A method of operating a redox flow battery, may include maintaining a positive electrode compartment pressure greater than a negative electrode compartment pressure, and maintaining a cross-over pressure less than a membrane break-through pressure, wherein the cross-over pressure equals the negative electrode compartment pressure subtracted from the positive electrode compartment pressure. In this way, ionic resistance across the separator can be maintained at a lower level by reducing gas bubbles trapped therein while reducing separator break-through, thereby increasing performance of the redox flow battery system.