Abstract text

As an electrochemical cell stack gets older the internal resistances within the stack rise overtime as the materials that the stack is made of degrade. Consequently, an old and “worn” electrochemical cell stack draws less current at the same stack voltage and operating temperature as a new stack. When the current draw falls the electrochemical reaction rates also fall, as less energy is available to drive the electrochemical reactions. However, if the operating temperature of an older stack is controllably raised the current draw by an electrolyzer cell stack also rises, which in turn causes the reaction rates to rise again. Accordingly, in some embodiments, a balance-of-plant system is operable to regulate the current draw of an electrolyzer cell stack by first manipulating the operating temperature of the same electrolyzer cell stack.