Self-balancing heat accumulating micro module

Abstract

The application provides a self-balancing heat storage micro module, which comprises an outer cavity 1, a cavity shell 2, an inner cavity 3, a heat resistance plate 4 and a porous permeation membrane 5, wherein phase change energy storage micro particles and medium liquid are arranged in the outer cavity 1 and the inner cavity 3. When the ambient temperature is extremely high, the high energy can be effectively blocked from transferring to the indoor by the permeation membrane; the indoor temperature is significantly reduced; when the ambient temperature is relatively low, the solar heat energy can be absorbed in the daytime and slowly released at night, so that the indoor temperature is improved. The heat collecting and heat dissipating process is slow, and the temperature changes gently; the heat collecting micro particles and the medium liquid are used as circulating materials, so that the module can be used for a long time and is environment-friendly, and has high economic value and application value.

Description

Technical Field

[0001] This invention relates to the field of building insulation, specifically to an energy storage and heat release module that is pre-embedded in the exterior wall, greenhouse, or basement of a building and slowly releases heat. Background Technology

[0002] In fields such as building energy conservation, agricultural production temperature control, and industrial waste heat recovery and utilization, the timing matching and efficient utilization of heat have always been core pain points of concern for the industry. Currently, there is a common supply and demand imbalance in scenarios such as building exterior walls, agricultural greenhouses, and basement roofs, characterized by "daytime heat surplus and nighttime heat shortage." Meanwhile, a large amount of low-grade waste heat generated during industrial production is directly emitted without effective recovery and cascade utilization, resulting in serious energy waste and environmental thermal pollution.

[0003] To address the aforementioned issues, various energy storage and heat release technologies and devices have emerged in the existing field, primarily employing water, phase change materials (such as paraffin wax and fatty acids), and concrete as energy storage media. Among these, water-based energy storage devices are simple in structure and low in cost, but suffer from drawbacks such as low energy storage density and large size, making them unsuitable for applications in confined spaces such as building exterior wall embedding and greenhouse mezzanine. While phase change material energy storage devices possess high energy storage density, their phase change temperature is fixed, making it difficult to dynamically adjust the heat release rate according to changes in ambient temperature. Furthermore, they are prone to problems such as phase change material leakage, excessive supercooling, and poor cycle stability, limiting their widespread application in long-term continuous operation scenarios.

[0004] Regarding heat isolation and directional release, existing energy storage devices mostly employ static sealing or unidirectional heat conduction structures, lacking dynamic adaptation mechanisms for isolation and migration. For example, some building exterior wall energy storage structures achieve unidirectional heat transfer by setting up insulation layers, but these insulation layers cannot adaptively adjust according to day and night temperature changes, easily leading to inefficient heat storage during the day and rapid heat loss at night. Some waste heat recovery devices use pumps to drive the circulation of the energy storage medium, which can achieve heat transfer, but requires additional electrical energy, increasing system energy consumption. Moreover, they are structurally complex and have high maintenance costs, making them unsuitable for distributed, low-cost application scenarios.

[0005] Furthermore, for scenarios requiring the slow release of heat energy, such as building heating and greenhouse temperature control, existing technologies struggle to achieve precise timing matching of the entire "heat absorption-energy storage-heat release" process. On one hand, the ambient heat absorbed during the day or waste heat from equipment cannot be efficiently stored in a limited space, leading to heat loss. On the other hand, when releasing heat at night, it is difficult to control the release rate, resulting in excessive temperature fluctuations in the target area and failing to meet the constant temperature requirement.

[0006] In summary, current energy storage and heat release technologies and devices suffer from drawbacks such as low energy density, difficulty in controlling the heat release rate, high system energy consumption, and complex structures. These limitations make it difficult to meet the demands of scenarios such as building exteriors, greenhouses, and basement roofs for slow heat release, time-sequential control of waste heat, and cascade utilization. Therefore, developing an energy storage and heat release module that is simple in structure, low in cost, and capable of efficient heat storage and slow release, adapting to diurnal temperature variations, is of significant practical importance for improving energy efficiency, reducing building energy consumption, and promoting agricultural production and industrial waste heat recovery. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a self-balancing thermal storage micro-module capable of intelligent bidirectional temperature control—"heat insulation during the day and heat release at night"—significantly mitigating indoor temperature fluctuations. This module operates entirely passively with zero energy consumption, relying solely on material phase change and fluid dynamics principles to achieve autonomous heat transfer and balance. It boasts high cycle stability and a long lifespan, ensuring long-term reliable system operation. Furthermore, the module employs a standardized and modular design, facilitating industrial production, transportation, and on-site assembly, adapting to various building scenarios.

[0008] This invention relates to a self-balancing thermal storage micro-module, comprising: an outer cavity 1, a cavity shell 2, an inner cavity 3, a heat-reflecting plate 4, and a porous permeable membrane 5, wherein phase change energy storage microparticles and a medium liquid are disposed in the outer cavity 1 and the inner cavity 3; the porous permeable membrane 5 is disposed between the outer cavity 1 and the inner cavity 3 to block the free diffusion of the phase change energy storage microparticles in the outer cavity 1 and the inner cavity 3.

[0009] Furthermore, a heat-reflecting plate is installed on the outer surface of the inner cavity 3.

[0010] Furthermore, the phase change energy storage microparticles use n-octadecane or lauric acid as the phase change substrate and incorporate 5-10 wt% expanded graphite.

[0011] Furthermore, the phase transition point of n-octadecane is about 28°C, the phase transition point of lauric acid is about 44°C, and the particle size of expanded graphite is less than or equal to 20 μm.

[0012] Furthermore, the phase change energy storage microparticles have a core-shell structure.

[0013] Furthermore, the core-shell structure is obtained by encapsulating phase change energy storage material with a 1-2 μm thick silica (SiO2) or polymer sealed shell.

[0014] Furthermore, the latent heat of phase change of phase change energy storage microparticles is ≥ 180 kJ / kg, the solid density is 900 kg / m³, the molten density is 800 kg / m³, and the volume expands by 12-15% when molten, or the corresponding particle size increases from 150-200 μm in the solid state to 220-260 μm in the molten state.

[0015] Furthermore, the porous permeation membrane 5 is a nanofiltration membrane made of polytetrafluoroethylene (PTFE), and the chamber shell 2 uses high-purity ASA resin as the base material, the content of which should not be less than 90%.

[0016] Furthermore, the heat-reflecting plate 4 is made of 2.0mm thick aluminum-plated steel plate, and the center of the arc is consistent with the inner cavity.

[0017] Furthermore, the medium liquid is selected as hydrogenated terphenyl.

[0018] Compared with the prior art, this application has the following advantages: 1) In summer when the temperature is extremely high, the permeable membrane can effectively block the transfer of high energy into the room, significantly reducing the indoor temperature; in winter when the temperature is low, it can absorb solar heat during the day and slowly release it at night, increasing the indoor temperature. 2) The entire heat collection and dissipation process is slow, and the temperature changes gradually without sudden increases or decreases in temperature. 3) The heat-collecting microparticles and the medium liquid are circulating materials, meaning that repeated heat absorption and release and volume changes will not affect the lifespan. They can be used for a long time and are environmentally friendly, and will not cause environmental pollution. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] The structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0021] Figure 1 This is a schematic diagram of the self-balancing thermal storage micro-module structure of the present invention. Detailed Implementation

[0022] The embodiments of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the following description is provided in conjunction with the appendix. Figure 1 The present application will be further described in detail with reference to specific embodiments.

[0024] This invention relates to a self-balancing thermal storage micro-module, see attached document. Figure 1 It mainly includes: an outer cavity 1, a cavity shell 2, an inner cavity 3, a reflector plate 4, and a porous permeable membrane 5. The outer cavity 1 and the inner cavity 3 contain phase change energy storage microparticles and a liquid medium; the porous permeable membrane 5 is positioned between the outer cavity 1 and the inner cavity 3 to block the diffusion of the phase change energy storage microparticles. A heat-reflecting plate is installed on the inner cavity 3.

[0025] The phase change energy storage microparticles use n-octadecane (phase change point approximately 28°C) or lauric acid (phase change point approximately 44°C) as the phase change substrate. To improve thermal conductivity, 5-10 wt% expanded graphite (particle size <20 μm) is incorporated. To prevent leakage of the phase change material in the molten state, each particle undergoes surface coating treatment to form a 1-2 μm thick silica (SiO2) or polymeric sealant shell. Key performance parameters of the phase change energy storage microparticles include: latent heat of phase change ≥ 180 kJ / kg, solid density: ~900 kg / m³; molten density: ~800 kg / m³; volume change: approximately 12-15% volume expansion during melting, or a corresponding increase in particle size from 150-200 μm in the solid state to 220-260 μm in the molten state. This design forms the basis of the permeation screening mechanism.

[0026] The medium liquid is hydrogenated terphenyl (heat transfer oil), which has stable chemical properties and low viscosity (≤30 mPa·s at 25°C) within the working temperature range (-20°C to 120°C). It also has good compatibility with the coated phase change particles, providing a carrier for the Brownian motion and migration of the particles.

[0027] The porous permeation membrane is a nanofiltration membrane made of polytetrafluoroethylene (PTFE), which is chemically inert, heat-resistant, and flexible. The average pore size of the membrane is designed to be 210±20μm. This pore size is larger than the solid particle size (≤200μm) but slightly smaller than the particle size after molten expansion (≥220μm), thus achieving intelligent screening and blocking based on particle state. The membrane porosity is controlled at 40%-50% to ensure sufficient permeability.

[0028] The outer cavity 1 and inner cavity 3 are constructed from the outer shell material. The outer shell material uses high-purity ASA resin as the base material, with a content of no less than 90%. The high-purity ASA resin should have a tensile strength of no less than 40 MPa, a flexural strength of no less than 60 MPa, and an impact strength (with notch) of no less than 10 kJ / m². These mechanical properties ensure that the module possesses sufficient strength and toughness during transportation, installation, and use, resisting external impacts and deformation.

[0029] The heat-reflecting plate is made of 2.0mm thick aluminum-plated steel plate. The arc center is aligned with the inner cavity, which can effectively concentrate and reflect heat, improve the heat dissipation efficiency of the inner side, and at the same time strengthen the positioning and fixation of the module in the wall.

[0030] The self-balancing thermal storage micro-module mainly consists of two stages during operation: 1) Daytime heat storage and insulation stage: When exposed to sunlight, the temperature of the outer cavity of the module rises above the phase change point. The internal phase change particles absorb heat and melt, expanding in volume and increasing in particle size to over 220 μm.

[0031] The expanded particles are effectively blocked in the outer chamber by a permeable membrane with a pore size of approximately 210 μm, preventing them from entering the inner chamber. At this time, the heat is mainly stored in the particles in the outer chamber, significantly blocking the immediate transfer of high-temperature heat to the inner side, thus playing a role in heat insulation.

[0032] 2) Nighttime heat release and heating phase: As the ambient temperature drops (e.g., at night), the temperature of the particles in the outer chamber falls below the phase transition point, causing them to begin solidifying and releasing heat. Their volume shrinks, and the particle size recovers to below 200 μm.

[0033] After shrinking, the particles in the liquid medium rely on Brownian motion and the slight pressure difference caused by the temperature difference between the inner and outer chambers to pass smoothly through the permeation membrane and slowly migrate to the inner chamber.

[0034] The particles continue to release latent heat of phase change within the inner chamber, and the heat is slowly conducted to the indoor space through the module shell to achieve nighttime heating.

[0035] When the temperature and concentration of particles in the inner and outer chambers become uniform, the thermal driving force (temperature difference) disappears, particle migration stops, and the system reaches dynamic equilibrium. This cycle restarts only when the next significant temperature difference occurs.

[0036] The heat capacity of a single module can be calculated using the following formula: Q = m * [Cp * (T2 - T1) + L] Where m is the total mass of particles within the module (e.g., 0.5 kg), and Cp is the specific heat (approximately 2.0 kJ / (kg·K)). (T2-T1) is the operating temperature rise (e.g., 15°C), and L is the latent heat (≥180 kJ / kg).

[0037] Among them, the module's thermal storage density is ≥ 200 kJ / kg (refer to GB / T 39286-2020); Module cycle stability: After 3000 accelerated "melt-solidify" cycles, the heat storage capacity decay rate is <8%.

[0038] Summer heat insulation effect: Compared with ordinary exterior walls, the peak temperature of the inner surface of the exterior wall using this module can be reduced by 5-8°C, and the heat insulation efficiency is ≥70%.

[0039] Temperature fluctuation suppression: Under typical sunlight conditions, the daily temperature fluctuation of the room using this module can be controlled within 2°C (compared to the control group which often exceeds 5°C).

[0040] In one embodiment, based on 10 modules installed per square meter of wall, each module has a total heat storage capacity of approximately 95-110 kJ, which can effectively buffer the temperature drop at night for 6-8 hours. The module has significant heat insulation and temperature regulation capabilities, with remarkable effects.

[0041] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components to achieve the purpose of this invention.

[0042] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

[0043] The various embodiments in this specification are described in a progressive, parallel, or combined manner. Each embodiment focuses on its differences from other embodiments, and similar or identical parts between embodiments can be referred to interchangeably. For the apparatuses disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0044] It should also be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes the aforementioned element.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A self-balancing thermal storage micro-module, characterized in that: include: The structure includes an outer cavity 1, a cavity shell 2, an inner cavity 3, a heat-reflecting plate 4, and a porous permeable membrane 5. The outer cavity 1 and the inner cavity 3 contain phase change energy storage microparticles and a medium liquid. The porous permeable membrane 5 is disposed between the outer cavity 1 and the inner cavity 3 to block the free diffusion of the phase change energy storage microparticles between the outer cavity 1 and the inner cavity 3.

2. The self-balancing thermal storage micro-module according to claim 1, characterized in that: A heat-reflecting plate is installed on the outer surface of the inner cavity 3.

3. The self-balancing thermal storage micro-module according to claim 1, characterized in that: The phase change energy storage microparticles use n-octadecane or lauric acid as the phase change substrate and incorporate 5-10 wt% expanded graphite.

4. The self-balancing thermal storage micro-module according to claim 3, characterized in that: The phase transition point of n-octadecane is about 28°C, the phase transition point of lauric acid is about 44°C, and the particle size of expanded graphite is less than or equal to 20 μm.

5. The self-balancing thermal storage micro-module according to claim 4, characterized in that: Phase change energy storage microparticles have a core-shell structure.

6. The self-balancing thermal storage micro-module according to claim 5, characterized in that: The core-shell structure is obtained by encapsulating phase change energy storage material with a 1-2 μm thick silica (SiO2) or polymer sealed shell.

7. The self-balancing thermal storage micro-module according to claim 6, characterized in that: The latent heat of phase change of phase change energy storage microparticles is ≥ 180 kJ / kg, with a solid density of 900 kg / m³ and a molten density of 800 kg / m³. When molten, the volume expands by 12-15% or the corresponding particle size increases from 150-200 μm in the solid state to 220-260 μm in the molten state.

8. The self-balancing thermal storage micro-module according to claim 4, characterized in that: The porous permeation membrane 5 is a nanofiltration membrane made of polytetrafluoroethylene (PTFE), and the chamber shell 2 is made of high-purity ASA resin as the base material, the content of which should not be less than 90%.

9. The self-balancing thermal storage micro-module according to claim 2, characterized in that: The heat-reflecting plate 4 is made of 2.0mm thick aluminum-plated steel plate, and the center of the arc is consistent with the inner cavity.

10. The self-balancing thermal storage micro-module according to claim 9, characterized in that: The medium liquid is hydrogenated terphenyl.

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