Fuel cell system

The invention discloses a fuel cell system which comprises an electric pile assembly, an air system, a hydrogen system and a thermal management system, the hydrogen system comprises a hydrogen source and a hydrogen circulation loop which are communicated, and the hydrogen circulation loop is provided with a circulation pump in series; the air system comprises an air inlet branch and an air outlet branch. The air inlet branch is sequentially provided with an air compressor and an intercooler in series. The heat management system comprises a liquid cold source, a galvanic pile heat exchange loop, an auxiliary heat exchange loop, a first circulation loop and a second circulation loop, the first circulation loop and the second circulation loop both communicate with the liquid cold source, the galvanic pile heat exchange loop is sequentially provided with a main water pump and a main heat exchanger in series, and the first circulation loop is used for exchanging heat with the main heat exchanger; the auxiliary hea