Methods and systems for controlling water imbalance in an electrochemical cell

A method of controlling water imbalance in an electrochemical cell, comprising:

• determining a present water imbalance in the electrochemical cell by summing a waterin and a watercreated less a waterout, wherein:
• waterin is an amount of water introduced into the electrochemical cell by an oxidant feed gas;
• watercreated is an amount of water created by the electrochemical cell from the electrochemical reaction;
• and
• waterout is an amount of water discharged from the electrochemical cell by an oxidant exhaust gas;
• tracking a cumulative water imbalance during operation of the electrochemical cell by repeatedly determining the present water imbalance and summing the present water imbalances;
• adjusting a flow rate of the oxidant feed gas entering the electrochemical cell based on the cumulative water imbalance;
• wherein a coolant is supplied to the electrochemical cell at a generally fixed inlet coolant temperature, and the inlet coolant temperature is set based on a set of ambient conditions in a way that ensures a potential maximum oxidant gas flow rate needed to bring the cumulative water imbalance to zero is within the operating limits of a compressor supplying the oxidant feed gas flow.