Fuel cell system and start-up control method therefor

A fuel cell system including a fuel cell, for conducting, depending on a necessity of a warm-up, a rapid warm-up operation performing a rapid warm-up on the fuel cell at the time of starting at a temperature blow freezing point, the system comprising:

• a memory programmed to store an operation termination condition of the last operation of the system;
• a judgment device which calculates a remaining amount of product water based on data read out from the memory at the time of starting the system to make judgments, from the remaining amount and a start-up associated temperature which reflects an internal temperature of the fuel cell at the time of starting, on whether or not a rapid warm-up of the system is necessary and whether to start without circulating the cooling water of the fuel cell when a rapid warm-up is necessary;
• and
• a power generation control device which conducts the rapid warm-up operation by executing, based on the judgment result provided by the judgment device, with or without circulating the cooling water, a low-efficiency power generation where a reactant gas to be supplied to the fuel cell is less than that in a normal power generation and an electronic power loss is larger than that in a normal power generation,
• wherein the judgment device comprises an impedance measuring function programmed to measure an impedance of the fuel cell and an associated temperature measuring function programmed to measure an associated temperature which reflects the internal temperature of the fuel cell, and calculates the remaining amount of the product water by a formula based on data including the measurement result of the impedance at the time of the last termination of the operation and the measurement result of the associated temperature,
• wherein the data includes an impedance at the time of the last termination of the operation of the fuel cell, the associated temperature at the time of the last termination of the operation of the fuel cell, and an accumulated amount of scavenging air for discharging water in the fuel cell at the time of the last termination of the operation of the fuel cell,
• wherein a graph of the start-up associated temperature of the fuel cell—the remaining amount of the product water (Vw) is divided into a plurality of zones, and a judgment whether to start without circulating the cooling water is made depending on which zone of the plurality of zones the start-up associated temperature at the time of starting the fuel cell and the remaining amount at the time of starting the fuel cell belong to, and
• wherein the fuel cell system is mounted on a fuel cell vehicle, and, at the time of starting at a temperature below freezing point, a judgment whether the fuel cell vehicle can drive is made by the judgment device.