Fuel cell system and working method thereof

The invention provides a working method of a fuel cell system, which comprises the following steps: S101, monitoring the conductivity of cooling water in an internal circulation water path of the fuel cell system, and S102, discharging at least part of the cooling water from the internal circulation water path when the conductivity of the cooling water is higher than a first threshold value, and meanwhile, water in a water tank of the fuel cell system is supplemented to the internal circulation water path. 本发明提供一种燃料电池系统的工作方法，其包括步骤S101、监测所述燃料电池系统的内循环水路中的冷却水的电导率S102、当所述冷却水的电导率高于第一阈值时，将至少部分所述冷却水从所述内循环水路中排出，同时将所述燃料电池系统的水箱中的水补充至所述内循环水路。