Open planar phase change heat storage tank

The invention discloses an open planar phase change heat storage tank. The heat storage tank mainly comprises a heat storage water tank (1), a clamping groove plate (2), a guide groove (3), a phase change heat storage plate (4), a thermal insulation layer (5), a high-temperature hot water injection pipe (6), a hot water supply pipe (7) and a water return pipe (8). Valves are installed on the pipes to regulate flow, a phase change heat storage material is installed in the phase change heat storage plate, a phase change material with the phase change temperature to be equal to hot water temperature is adopted according to requirements, and a phase change temperature range is 0-100 DEC G. When high-temperature hot water is supplied, the hot water is injected in the heat storage water tank, and heat of the hot water is stored in the phase change heat storage material. When supply of the high-temperature hot water is stopped, the phase change heat storage plate releases heat to enable water in the water tank to ma