Expansion tank and hybrid vehicle

The utility model relates to an expansion water tank and a hybrid power vehicle, the expansion water tank is used for the hybrid power vehicle, the hybrid power vehicle comprises a three-electric cooling pipeline and an engine cooling pipeline, and the expansion water tank comprises an expansion water tank body and a partition plate arranged in the expansion water tank body. The space in the expansion water tank body is divided into a three-electric cooling system cavity and an engine cooling system cavity through the partition plate, and the three-electric cooling system cavity is located above the engine cooling system cavity. The engine cooling system cavity is used for containing engine cooling liquid, and the bottom height of the partition plate is larger than the liquid level height of the engine cooling liquid. The heat of the engine cooling liquid can be prevented from being directly transmitted to the three-electric cooling liquid through the partition plate, so that the three-electric cooling liquid