Method for testing cycle performance of stable supercooled hydrated salt system phase change material
By adding foil, inert nanopowder or mica sheets to the DSC test, the problem of cycling performance testing of stable supercooled hydrated salt system is solved, and accurate cycling performance testing is achieved without additional monitoring.
Patent Information
- Application Number
- CN202510517968.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-23
- Publication Date
- 2025-07-22
AI Technical Summary
The prior art cannot effectively test the phase transition cycle performance of a stable supercooled hydrated salt system, and the existing methods are costly, require additional monitoring and interference system composition, or can only conduct head-to-tail cycle performance comparison.
Add foil, inert nano powder or mica sheet to the DSC test to spontaneously induce stable supercooled hydrated salt system crystals to achieve cycle performance testing.
It realizes in-situ tracking of each cycle of the sample without additional monitoring, accurately displaying the evolution of phase change behavior, and provides fast and accurate cycle performance testing.
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Figure CN120352469A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of performance testing of hydrated salt-based phase change materials, and particularly relates to a method for testing the cycling performance of a stable supercooled hydrated salt-based phase change material. Background Art
[0002] The cycling performance of hydrated salt-based phase change energy storage materials is usually rapidly and preliminarily tested by differential scanning calorimetry (DSC method). However, since a hydrated salt system with stable supercooling behavior cannot nucleate and crystallize, the phase change cycle test of a supercooling-stable hydrated salt system cannot be achieved by DSC, and only one test can be performed.
[0003] Currently, for the problem that a stable supercooled hydrated salt cannot perform melting and crystallization cycles, the existing technologies mainly involve continuously externally providing seed stimulation during the test of cycling performance to cause the hydrated salt to crystallize. Another method is to place a shrapnel (bent iron sheet) in a well-sealed hydrated salt soft package, and through the bending and rebound of the shrapnel, the cycling of a sample on a larger scale (greater than or equal to several tens of grams) is achieved. After cycling, a sample is taken for a single DSC test. Through the above two methods, the cycling of the hydrated salt system can be achieved, and by comparing the thermophysical properties before and after cycling, the cycling stability performance of the material can be tested. Using the method of continuously stimulating the seed to cause the hydrated salt to crystallize will cause the system to continuously contact foreign substances, interfering with the system composition, and unable to truly reflect the cycling performance of the system itself. Moreover, the test cost is high, and the cycling state needs to be monitored at any time to give seed induction in a timely manner. By the method of inducing the system to crystallize by placing an iron shrapnel in a sealed container / soft package, on the one hand, the cycling state needs to be monitored at any time to give a bending and rebound response in a timely manner to induce crystallization, and for hundreds or thousands of cycling tests, the cost is relatively high; on the other hand, in this method, only the samples before and after cycling are taken for DSC thermophysical property tests. Therefore, only the performance changes of the first and last cycles can be compared, and the thermophysical property changes of the sample during each cycle cannot be tracked in real time in situ, which brings great inconvenience to the development of the experiment. Summary of the Invention
[0004] The main purpose of the present invention is to provide a method for testing the cycling performance of a stable supercooled hydrated salt-based phase change material to overcome the deficiencies of the prior art.
[0005] To achieve the foregoing invention purpose, the technical solutions adopted by the present invention include:
[0006] An embodiment of the present invention provides a method for testing the cycling performance of a stable supercooled hydrated salt-based phase change material, which includes:
[0007] Providing a stable supercooled hydrated salt-based phase change material;
[0008] Place the phase change material of the stable supercooled hydrated salt system in the sample cell, then add any one of foil, inert nanoflour, and mica sheet, and then perform DSC cyclic tests to achieve the cyclic performance test of the phase change material of the stable supercooled hydrated salt system; wherein, at least one of the foil, inert nanoflour, or mica sheet can spontaneously induce the crystallization of the phase change material of the stable supercooled hydrated salt system.
[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: The test method provided by the present invention can achieve DSC cyclic tests of stable supercooled salts, without additional monitoring, in-situ tracking of the changes of the sample in each cycle, accurately and truly demonstrating the evolution process of the phase change behavior, and more precisely revealing the evolution mechanism. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0011] Figure 1 It is a schematic diagram of adding convex aluminum foil, concave aluminum foil, mica sheet or mica powder full load in the crucible sample cell in a typical implementation scheme of the present invention;
[0012] Figure 2 It is a DSC curve graph of the first cycle of the stable supercooled hydrated salt SAT in Example 1 of the present invention;
[0013] Figure 3 It is a DSC curve graph of the second cycle of the stable supercooled hydrated salt SAT in Example 1 of the present invention;
[0014] Figure 4 It is a DSC curve graph of SAT after introducing paper / powder paper in Example 1 of the present invention;
[0015] Figure 5 It is a DSC curve graph of 3 cycles of SAT after placing convex aluminum foil in the crucible sample cell in Example 1 of the present invention;
[0016] Figure 6 It is a DSC curve graph of 11 cycles of SAT after placing concave aluminum foil in the crucible sample cell in Example 2 of the present invention;
[0017] Figure 7 It is a DSC curve graph of the 1st - 2nd cycles of SAT full load with alumina powder in Example 3 of the present invention;
[0018] Figure 8It is the DSC curve of the 3rd - 7th cycles of SAT filled with alumina powder in Embodiment 3 of the present invention;
[0019] Figure 9 It is the DSC curve of the 11th cycle of SAT filled with mica powder in Embodiment 3 of the present invention;
[0020] Figure 10 It is the DSC curve of mica powder in Embodiment 3 of the present invention;
[0021] Figure 11 It is the DSC curve of the first cycle of SAT with mica flakes introduced in Embodiment 4 of the present invention;
[0022] Figure 12 It is the DSC curve of the second cycle of SAT with mica flakes introduced in Embodiment 4 of the present invention. Detailed implementation manners
[0023] In view of the defects of the prior art, the inventors of this case have, through long - term research and a large number of practices, proposed the technical solution of the present invention. It mainly overcomes the problem that the sample cannot nucleate and crystallize by modifying the test sample cell (crucible) to realize the phase - change cycle performance test of a stable supercooled hydrated salt system.
[0024] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.
[0025] One aspect of the embodiments of the present invention provides a method for testing the cycle performance of a phase - change material of a stable supercooled hydrated salt system, including:
[0026] Providing a phase - change material of a stable supercooled hydrated salt system;
[0027] Placing the phase - change material of the stable supercooled hydrated salt system in a sample cell, then adding any one of a foil, an inert nanopowder, and mica flakes, and then performing a DSC cycle test, thereby realizing the cycle performance test of the phase - change material of the stable supercooled hydrated salt system; wherein, the foil, the inert nanopowder, or the mica flakes can at least spontaneously induce the crystallization of the phase - change material of the stable supercooled hydrated salt system.
[0028] In some more specific implementation schemes, the phase - change material of the stable supercooled hydrated salt system includes any one of a single - hydrated - salt - system phase - change energy - storage material, a binary - hydrated - salt - system phase - change energy - storage material, and a multi - hydrated - salt - system phase - change energy - storage material, and is not limited thereto.
[0029] In some more specific embodiments, the stable supercooled hydrated salt system phase change material includes any one of hydrated sodium acetate trihydrate, calcium chloride hexahydrate, and sodium sulfate decahydrate, and is not limited thereto.
[0030] In some more specific embodiments, the foil includes aluminum foil and / or copper foil, and is not limited thereto.
[0031] Further, the aluminum foil includes convex aluminum foil and / or concave aluminum foil.
[0032] In some more specific embodiments, the test method specifically includes:
[0033] Place the stable supercooled hydrated salt system phase change material in the sample cell, then add the convex aluminum foil so that the stable supercooled hydrated salt system phase change material is located in the interval surrounded by the convex aluminum foil and the bottom of the sample cell, and then perform a DSC cycle test to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
[0034] In some more specific embodiments, the test method specifically includes:
[0035] Place the concave aluminum foil in the sample cell, then add the stable supercooled hydrated salt system phase change material into the concave aluminum foil so that the stable supercooled hydrated salt system phase change material is located inside the concave aluminum foil, and then perform a DSC cycle test to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
[0036] In some more specific embodiments, the inert nanopowder includes mica powder, and is not limited thereto.
[0037] In some more specific embodiments, the test method specifically includes:
[0038] Place the stable supercooled hydrated salt system phase change material in the sample cell, then add mica powder to fill the sample cell with mica powder, and the mica powder covers the surface of the stable supercooled hydrated salt system phase change material, and then perform a DSC cycle test to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
[0039] In some more specific embodiments, the test method specifically includes: Place the stable supercooled hydrated salt system phase change material in the sample cell, then add mica flakes, and then perform a DSC cycle test to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
[0040] In some more specific embodiments, the stable supercooled hydrated salt system phase change material cannot achieve cycling during a conventional DSC cycle test.
[0041] In some more specific embodiments, the method for testing the cycling performance of the stable supercooled hydrated salt system phase change material includes:
[0042] 1) Sampling the newly prepared hydrated salt system phase change energy storage material for conventional DSC cycling tests, as Figure 1 shown in (1) below;
[0043] 2) Obtaining the DSC curves of the thermophysical properties (melting enthalpy, melting temperature, solidification enthalpy, and solidification temperature) of the sample through step 1;
[0044] 3) If, in the conventional DSC cycling test, cycling cannot be achieved and only one test can be performed, it can be determined that the hydrated salt system belongs to a stable supercooled system;
[0045] 4) For the hydrated salt system belonging to stable supercooling, add convex aluminum foil to the crucible sample pool during the test, as Figure 1 shown in (2) below. If the changes of the sample can be monitored for each cycle, it indicates that placing convex aluminum foil in the crucible sample pool can achieve the cycling performance test of the hydrated salt system phase change energy storage material;
[0046] 5) Add concave aluminum foil to the crucible sample pool during the test, as Figure 1 shown in (3) below. If the changes of the sample can be monitored for each cycle, it indicates that placing concave aluminum foil in the crucible sample pool can achieve the cycling performance test of the hydrated salt system phase change energy storage material;
[0047] 6) Fill the crucible sample pool with mica powder during the test, as Figure 1 shown in (4) below. If the changes of the sample can be monitored for each cycle, it indicates that filling the crucible sample pool with mica powder can achieve the cycling performance test of the hydrated salt system phase change energy storage material;
[0048] 7) Introduce mica sheets into the crucible sample pool during the test, as Figure 1 shown in (5) below. If the changes of the sample can be monitored for each cycle, it indicates that introducing mica sheets into the crucible sample pool can achieve the cycling performance test of the hydrated salt system phase change energy storage material.
[0049] In view of the problem that it is not suitable to conduct cycling performance tests during the cycling performance test of the existing stable supercooled hydrated salt system phase change energy storage material, the present invention provides a method for spontaneously inducing crystallization of the system in the sample pool, which can achieve in-situ tracking of the changes of the sample for each cycle, display the evolution process of the phase change behavior, and realize the cycling performance test of the hydrated salt system material based on DSC without additional monitoring and with high precision and authenticity, providing a powerful solution for the rapid preliminary test of the cycling performance of the stable supercooled hydrated salt system.
[0050] The technical solution of the present invention will be further described in detail below in conjunction with several preferred embodiments and the accompanying drawings. These embodiments are implemented on the premise of the technical solution of the invention, and detailed implementation manners and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.
[0051] In the following embodiments, the experimental materials used can be obtained from conventional biochemical reagent companies without special instructions.
[0052] Example 1
[0053] The DSC phase change cycle performance test of hydrated salt sodium acetate trihydrate (SAT) is realized by placing convex aluminum foil in the crucible sample cell.
[0054] (1). Sampling the newly prepared SAT hydrated salt system for the first DSC cycle test (as Figure 2 ), it can be found that there is no exothermic peak during the cooling process of the sample;
[0055] (2). Continuing to perform the second DSC cycle test on the above sample (as Figure 3 ), it is found that under normal circumstances, SAT can only be subjected to one cycle test, and the DSC cycle of SAT cannot be realized;
[0056] (3). Placing weighing paper in the crucible sample cell for DSC test (as Figure 4 ), it is found that there is still no exothermic peak during the cooling process of the sample with the introduction of weighing paper, and the cycle of the sample cannot be realized;
[0057] (4). Placing convex aluminum foil in the crucible sample cell for DSC test (as Figure 1 in (2), Figure 5 ), performing 3 DSC cycles, the changes of the sample in each cycle can be tracked in-situ, and the DSC phase change cycle performance test of hydrated salt SAT can be realized.
[0058] Example 2
[0059] The DSC phase change cycle performance test of hydrated salt SAT is realized by placing concave aluminum foil in the crucible sample cell.
[0060] (1). Sampling the newly prepared SAT hydrated salt system into the crucible sample cell, placing concave aluminum foil for 11 DSC cycle tests (as Figure 1 in (3), Figure 6 ), the changes of the sample in each cycle can be tracked in-situ, and the DSC phase change cycle performance test of hydrated salt SAT is realized.
[0061] Example 3 The DSC phase change cycle performance test of hydrated salt SAT is realized by filling the crucible sample cell with mica powder.
[0062] (1). Samples of the newly prepared SAT hydrated salt system were taken into the crucible sample cell, and then alumina powder was filled in the crucible for DSC testing (as shown in Figure 7 ), and it was found that the SAT sample filled with alumina powder could undergo two cycles;
[0063] (2). The above samples were continuously subjected to 3 - 7 DSC cycle tests (as shown in Figure 8 ), and it was found that the DSC cycle test of SAT could not be achieved in the third cycle test;
[0064] (3). New stable supercooled SAT hydrated salt systems were re - prepared, samples were taken into the crucible sample cell, and then mica powder was filled in the crucible for 11 DSC tests (as shown in Figure 1 in (4), Figure 9 ), and the changes of the sample in each cycle could be tracked in situ, realizing the DSC phase change cycle performance test of the hydrated salt SAT;
[0065] (4). To verify whether the mica powder had an impact on the DSC test results, a blank control group was set up, and samples were taken for DSC testing of mica powder (as shown in Figure 10 ), and it was found that there was no evolution process of phase change behavior of mica powder in the same temperature range, indicating that mica powder had no interference with the SAT test, and it was proved that filling with mica powder could realize the DSC phase change cycle performance test of the hydrated salt SAT.
[0066] Example 4
[0067] Realizing the DSC phase change cycle performance test of the hydrated salt SAT by introducing mica flakes into the crucible sample cell
[0068] (1). Samples of the prepared stable supercooled SAT hydrated salt system were taken into the crucible sample cell, and then mica flakes were introduced into the crucible for the first DSC cycle test (as shown in Figure 1 (4), Figure 11 );
[0069] (2). The above samples were continuously subjected to the second DSC cycle test (as shown in Figure 12 ), and the changes of the sample in each cycle could be tracked in situ, realizing the DSC phase change cycle performance test of the hydrated salt SAT.
[0070] In addition, the inventors of this case also referred to the foregoing embodiments, and conducted tests with other raw materials, process operations, and process conditions described in this specification, and all obtained relatively ideal results.
[0071] It should be understood that the technical solutions of the present invention are not limited to the limitations of the above - mentioned specific embodiments. Any technical deformation made according to the technical solutions of the present invention without departing from the purpose of the present invention and the scope protected by the claims falls within the protection scope of the present invention.
Claims
1. A method for testing the cycling performance of a stable supercooled hydrated salt system phase change material, characterized in that Including: Providing a stable supercooled hydrated salt system phase change material; Placing the stable supercooled hydrated salt system phase change material in a sample cell, then adding any one of a foil, an inert nanopowder, and a mica sheet, and then performing a DSC cyclic test, so as to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material; wherein, the foil, the inert nanopowder or the mica sheet can at least spontaneously induce the crystallization of the stable supercooled hydrated salt system phase change material.
2. The test method according to claim 1, wherein: The stable supercooled hydrated salt system phase change material includes any one of a single hydrated salt system phase change energy storage material, a binary hydrated salt system phase change energy storage material, and a multi-component hydrated salt system phase change energy storage material.
3. The test method according to claim 1, characterized in that: The stable supercooled hydrated salt system phase change material includes any one of hydrated sodium acetate trihydrate, calcium chloride hexahydrate, and sodium sulfate decahydrate.
4. The testing method according to claim 1, wherein: The foil includes aluminum foil and / or copper foil; preferably, the aluminum foil includes convex aluminum foil and / or concave aluminum foil.
5. The test method according to claim 4, characterized in that Specifically including: Placing the stable supercooled hydrated salt system phase change material in a sample cell, then adding convex aluminum foil, so that the stable supercooled hydrated salt system phase change material is located in the interval surrounded by the convex aluminum foil and the bottom of the sample cell, and then performing a DSC cyclic test, so as to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
6. The test method according to claim 4, characterized in that, Specifically including: Placing the concave aluminum foil in the sample cell, then adding the stable supercooled hydrated salt system phase change material into the concave aluminum foil, so that the stable supercooled hydrated salt system phase change material is located in the concave aluminum foil, and then performing a DSC cyclic test, so as to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
7. The test method according to claim 1, wherein: The inert nanopowder includes mica powder.
8. The test method according to claim 7, characterized in that Characterized in that, specifically including: Placing the stable supercooled hydrated salt system phase change material in a sample cell, then adding mica powder to fill the sample cell with mica powder, and the mica powder covers the surface of the stable supercooled hydrated salt system phase change material, and then performing a DSC cyclic test, so as to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
9. The test method according to claim 6, characterized in that, Characterized in that, specifically including: placing the stable supercooled hydrated salt system phase change material in a sample cell, then adding a mica sheet, and then performing a DSC cyclic test, so as to realize the cyclic performance test of the stable supercooled hydrated salt system phase change material.
10. The test method according to claim 1, characterized in that: The stable supercooled hydrated salt system phase change material cannot achieve cycling during a conventional DSC cyclic test.