Abstract: A device and method for improving stack performance of a fuel cell system are provided. The device includes a fuel cell controller that operates a stack of a normal-pressure fuel cell system. When the fuel cell controller determines that an operating state of the stack is normal and a current intake air pressure is decreased as a result of monitoring the current intake air pressure, a current output, and an exterior air temperature of the stack, the fuel cell controller increases the amount of air to be supplied into the stack by adjusting a range of a theoretical air ratio which is a theoretical ratio of an air amount to a coolant temperature in the stack.

Abstract: An operation control method of a fuel cell system is provided that increases the output of a fuel cell stack by detecting and overcoming the cause of a performance limit when the stack reaches the performance limit during high-altitude operation of a fuel cell vehicle, thereby achieving higher stack performance and vehicle power performance. The method includes determining whether an operation state of the stack corresponds to a predetermined condition in which a stack output limit occurs by determining current operation state information of the stack. Additionally, operating pressure of an air pole is adjusted by changing an opening degree of an air pressure adjusting valve to a control command value based on the operation state of the stack when the operation state corresponds to the predetermined condition in which the stack output limit occurs.

Abstract: A device and method for improving stack performance of a fuel cell system are provided. The device includes a fuel cell controller that operates a stack of a normal-pressure fuel cell system. When the fuel cell controller determines that an operating state of the stack is normal and a current intake air pressure is decreased as a result of monitoring the current intake air pressure, a current output, and an exterior air temperature of the stack, the fuel cell controller increases the amount of air to be supplied into the stack by adjusting a range of a theoretical air ratio which is a theoretical ratio of an air amount to a coolant temperature in the stack.

Abstract: An operation control method of a fuel cell system is provided that increases the output of a fuel cell stack by detecting and overcoming the cause of a performance limit when the stack reaches the performance limit during high-altitude operation of a fuel cell vehicle, thereby achieving higher stack performance and vehicle power performance. The method includes determining whether an operation state of the stack corresponds to a predetermined condition in which a stack output limit occurs by determining current operation state information of the stack. Additionally, operating pressure of an air pole is adjusted by changing an opening degree of an air pressure adjusting valve to a control command value based on the operation state of the stack when the operation state corresponds to the predetermined condition in which the stack output limit occurs.