Heat storage apparatus for vehicle

When performing heat storage in a heat storage container accommodating a plurality of kinds of heat storage materials with different melting points, heat storage in the heat storage materials is performed such that a higher melting point heat storage material is in a latent heat storage state as much as possible. In other words, heat storage in the heat storage materials is performed in such a manner that the heat storage materials are in the latent heat storage state in which heat can be stored most effectively. In addition, when performing heat release from the heat storage container to heat coolant water in a circulation circuit, heat release is performed from the heat storage material in the sensible heat storage state as a priority, out of the heat storage materials. Accordingly, heat release from the heat storage container in the heat storage state is performed in such a manner that the heat storage materials are maintained in latent heat storage state for as a long period of time as possible. When heat release from the heat storage container is performed in this manner, the heat storage materials can be kept in the latent heat storage state for as a long period of time as possible. As in the foregoing, the heat storage container can be kept in the heat storage state for a long period of time.