A heat storage core and its preparation method, heat storage module and heat storage system

Abstract

The present invention provides a thermal storage core and its preparation method, thermal storage module, and thermal storage system. These materials belong to the field of phase change materials technology and overcome the drawbacks of existing thermal storage materials, such as the high latent heat loss and structural instability. The thermal storage core comprises an outer shell, a core phase change region, and a miscible layer disposed between the outer shell and the core phase change region. The outer shell is composed of a skeleton material, the core phase change region is composed of a core material, and the phase change temperature of the skeleton material is greater than that of the core material. The miscible layer is a composite material comprising the skeleton material and the core material, and the content of the core material in the miscible layer gradually increases from the outer shell to the core phase change region.

Claims

1. A method for preparing a heat storage core, characterized in that: The thermal storage core comprises an outer shell, a core phase change region and a miscible layer disposed between the outer shell and the core phase change region; The shell is composed of a skeleton material, the core phase change zone is composed of a core material, and the phase change temperature of the skeleton material is greater than the phase change temperature of the core material; The miscible layer is a composite material including a skeleton material and a core material, and the content of the core material in the miscible layer gradually increases from the shell to the core phase change region; The preparation method of the thermal storage core comprises the following steps: Step 1: Mix the core material and the skeleton material in different proportions; Step 2: Laying raw materials with different core material contents to obtain a structure in which the outer periphery is the skeleton material, the inner periphery is the core material, and the interface between the outer periphery and the inner periphery is the composite material; Step 3, pressing the structure formed in step 2 to obtain the heat storage core; In the step 2, the material is laid in the forming mold; The forming mold includes a forming component and an auxiliary paving component, the forming component includes a cavity, the auxiliary paving component is tubular, the auxiliary paving component is detachably arranged in the cavity, the outer wall of the auxiliary paving component and the inner wall of the cavity form a first space, and the interior of the auxiliary paving component is a second space; The step 2 includes: Step 201: Laying a skeleton material in the cavity; Step 202: placing the auxiliary paving assembly into the cavity; Step 203: Fill the first space with skeleton material; Step 204: Fill the second space with multiple layers of composite material, with the core material content in each layer increasing in a gradient manner; Fill with pure core material; Continue to fill in multiple layers of composite material, with the core material content in each layer decreasing in a gradient manner; Step 205: remove the auxiliary paving assembly and lay a layer of skeleton material on the top layer; In step 201 and / or step 205, the thickness of the laid skeleton material is 1-3 mm; The thickness of the first space perpendicular to the direction of the auxiliary paving component is 1-3 mm; In step 204 , the thickness of each layer of composite material is 2 to 8 mm.

2. The method for preparing a heat storage core according to claim 1, wherein: In step 3, the pressing pressure is 30 MPa-80 MPa, and the holding time is 10-30 seconds.

3. The method for preparing a heat storage core according to claim 1, wherein: The core material is a metal element or alloy; the skeleton material is an inorganic element, alloy or compound; The phase transition temperature of the skeleton material minus the phase transition temperature of the core material is ≥ 100°C; The difference in Mohs hardness between the skeleton material and the core material is ≤4.

4. The method for preparing a heat storage core according to claim 3, wherein: The core material is aluminum, zinc, tin, aluminum-zinc alloy, aluminum-magnesium alloy or aluminum-magnesium-zinc alloy; and / or The skeleton material is silicon, copper, aluminum silicon alloy, silicon magnesium alloy, aluminum silicon magnesium alloy, magnesium silicon zinc alloy, flaky graphite, expanded graphite, graphene, magnesium oxide or aluminum oxide; and / or The average particle size of the core material is 5 to 200 μm; and / or The average particle size of the skeleton material is 5 to 200 μm.

5. The method for preparing a heat storage core according to claim 3, wherein: The core material is tin, the skeleton material is graphite, the average particle size of the tin is 10 to 50 μm, the average particle size of the graphite is 20 to 80 μm, and in the composite material, the mass ratio of the tin to the graphite is (2 to 8):1; or The core material is tin, the skeleton material is aluminum, the average particle size of the tin is 10 to 50 μm, the average particle size of the aluminum is 50 to 150 μm, and the mass ratio of the tin to the aluminum in the composite material is (4 to 16):1; or The core material is an aluminum-zinc alloy, the skeleton material is magnesium oxide, the average particle size of the aluminum-zinc alloy is 20 to 80 μm, the average particle size of the magnesium oxide is 20 to 60 μm, and in the composite material, the mass ratio of the aluminum-zinc alloy to the magnesium oxide is (2 to 16):1; or The core material is aluminum silicon alloy, the skeleton material is silicon, the average particle size of the aluminum silicon alloy is 20 to 80 μm, the average particle size of the silicon is 10 to 40 μm, and in the composite material, the mass ratio of the aluminum silicon alloy to silicon is (0.5 to 2):

1.

6. A heat storage module, characterized in that: The invention relates to a heat storage core prepared by the preparation method according to any one of claims 1 to 5.

7. The thermal storage module according to claim 6, characterized in that: There are multiple heat storage cores, and the phase change temperature of the heat storage cores arranged inside the heat storage module is greater than that of the heat storage cores arranged outside the module.

8. A heat storage system, characterized in that: A heat storage core comprising a plurality of heat storage cores prepared by the preparation method according to any one of claims 1 to 5, further comprising a heating element, a power supply and a heat exchange pipeline; A plurality of heat storage cores form a heat storage array, the heating element is arranged in the heat storage array, the power supply is connected to the heating element, and the heat exchange pipeline is connected to the heat storage array.

Images