Conventionally, an operation temperature of an electrolyte material of a solid polymer fuel cell is lower than 100° C. In the conventional electrolyte material, since an ion is conducted through moisture in a film, a system for controlling the moisture in the electrolyte material is required.
From the viewpoints of reduction of the cost of the system for the solid polymer fuel cell and simplification of the system, an electrolyte material that has an operation temperature equal to or higher than 100° C. and operates under a non-humidification or a low-humidification condition. JP 2014-116276 A (corresponding to US 2014/0011103 A1) discloses such electrolyte material.