System and method for sensing and mitigating hydrogen evolution within a flow battery system
View Patent ↗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.
1. A method for mitigating hydrogen evolution within a flow battery system that comprises a plurality of flow battery cells, a power converter and an electrochemical cell, the method comprising:
providing hydrogen generated by the hydrogen evolution within the flow battery system to the electrochemical cell;
providing reactant to the electrochemical cell;
generating a first electrical current through an electrochemical reaction between the hydrogen and the reactant using the electrochemical cell; and
controlling an exchange of electrical power between the flow battery cells and the power converter in response to the first electrical current.
2. The method of claim 1 , wherein the reactant comprises air.
3. The method of claim 1 , wherein the controlling of the exchange of the electrical power comprises stopping the exchange of the electrical power between the flow battery cells and the power converter when the first electrical current is greater than a threshold value.
4. The method of claim 3 , wherein the threshold value corresponds to one of
where a first solution within the flow battery system has greater than approximately ninety percent state of charge; and
where hydrogen begins to form within the first solution.
5. The method of claim 1 , wherein the controlling of the exchange of electrical power comprises one of
reducing current density within the flow battery cells when the first electrical current is greater than a threshold value; and
reducing voltage across the flow battery cells when the first electrical current is greater than the threshold value.
6. The method of claim 5 , wherein the threshold value corresponds to one of
where a first solution within the flow battery system has greater than approximately ninety percent state of charge; and
where hydrogen begins to form within the first solution.
7. The method of claim 1 , wherein the controlling of the exchange of electrical power comprises:
sensing the first electrical current using a current sensor, and providing a current signal indicative of the sensed first electrical current to a controller; and
processing the current signal to provide a control signal to the power converter.
8. The method of claim 1 , wherein the hydrogen is provided to the electrochemical cell from a reservoir in the flow battery system that contains a first solution having a first reversible redox couple reactant.
9. The method of claim 8 , further comprising directing the hydrogen from the reservoir to the electrochemical cell through a valve.
10. The method of claim 8 , further comprising purging the hydrogen from the reservoir such that the hydrogen flows into the electrochemical cell.