Fuel cell system

摘要

The object is to suppress degradation of the durability of an electrolyte membrane caused by deformation by expansion and contraction of the electrolyte membrane. A controller 150 calculates a humidity P of an electrolyte membrane 112 based on a cell resistance value (step S11) and determines whether the humidity P of the electrolyte membrane 112 is less than a humidity threshold A (step S12). When the humidity P is less than the humidity threshold A, the controller 150 determines that a dimensional change rate of the electrolyte membrane is not greater than a predetermined value and performs a process of increasing the humidity of the electrolyte membrane 112 (step S13). The predetermined value is a dimensional change rate that is unlikely to have damage by drying stress. This enables the electrolyte membrane 112 to be humidified before the electrolyte membrane 112 is excessively dried and thereby suppresses tensile stress from being applied to the electrolyte membrane 112 by drying of the electrolyte membrane 112. Accordingly this suppresses cracking and thinning of the electrolyte membrane 112 and improves the durability of the electrolyte membrane 112.

主权项

1. A fuel cell system comprising:
a fuel cell configured to have a solid polymer electrolyte membrane; a controller configured to control the fuel cell; and an acquirer configured to obtain information on humidity of the electrolyte membrane, wherein when the humidity of the electrolyte membrane is equal to or less than a threshold value for a predetermined time, the controller is programmed to control a wet state of the electrolyte membrane such that a dimensional change rate of the electrolyte membrane, which is a change rate in area in a planar direction of the electrolyte membrane accompanied with expansion or contraction of the electrolyte membrane, is equal to or greater than a predetermined value which is greater than a dimensional change rate corresponding to a state in which the electrolyte membrane is damaged by tensile stress applied to the electrolyte membrane by drying of the electrolyte membrane, the threshold value is specified by a humidity range of the electrolyte membrane when the dimensional change rate of the electrolyte membrane is −1.5% to 0%, and the predetermined time is a predetermined time period from a time when the dimensional change rate of the electrolyte membrane becomes equal to 0% to a time when the dimensional change rate of the electrolyte membrane becomes less than 0%.