Body temperature power generation fabric and preparation method thereof

Abstract

This invention discloses a body-temperature power-generating fabric and its preparation method, belonging to the field of thermoelectric power generation technology. The body-temperature power-generating fabric comprises an upper layer of high thermal conductivity insulating fabric, a lower layer of high thermal conductivity insulating fabric, thermoelectric units, and an insulation layer. Conductive circuits are printed on both the upper and lower layers of high thermal conductivity insulating fabric. The thermoelectric units are arranged between the upper and lower layers and electrically connected to the conductive circuits. The insulation layer fills the area around the thermoelectric units. The preparation method includes: printing conductive circuits on the high thermal conductivity insulating fabric; arranging P-type and N-type thermoelectric materials; filling with insulation material; and assembling to obtain the body-temperature power-generating fabric. This invention organically combines textile processing technology with thermoelectric power generation technology, achieving high efficiency in body-temperature power generation while ensuring the comfort of the fabric itself. The power generation is adjustable and easy to prepare, making it suitable for mass production.

Description

Technical Field

[0001] This invention relates to the field of thermoelectric power generation technology, and in particular to a body temperature power generation fabric and its preparation method. Background Technology

[0002] With the development of wearable electronic devices, electronic components are becoming increasingly miniaturized to meet the needs of long-term wear, thus placing higher demands on power supply equipment. This requires not only sustained power delivery but also lightweight operation to improve wearability. Traditional battery power is currently the mainstream choice, but it faces the problems of frequent charging and battery replacement, and discarded batteries cause environmental pollution.

[0003] In existing technologies, scientists have conducted extensive research in areas such as solar power generation and triboelectric power generation, but these methods all require specific external conditions to function. Thermoelectric power generation is a green and environmentally friendly method that utilizes the Seebeck effect to convert heat energy into electrical energy. By connecting P-type and N-type materials into a closed loop, when a temperature difference exists between the two ends, thermal diffusion causes free electrons within the semiconductor material to accumulate at the lower temperature end, thus creating a potential difference and converting heat energy into electrical energy. Thermoelectric power generation has advantages such as simple structure, no moving parts, no noise, and ease of miniaturization.

[0004] Textiles possess inherent wearability advantages. By structurally designing fibers and their assemblies, high-performance flexible thermoelectric power generation devices can be fabricated, providing a continuous source of electricity for wearable electronic devices. However, current thermoelectric power generation devices typically use rigid ceramic substrates, leading to increased device weight and hindering heat harvesting from the human body. To address this issue, existing technology provides a flexible wearable thermoelectric energy harvesting device based on MEMS technology. The device structure, from bottom to top, consists of a lower PVDF substrate layer, thermoelectric arms made of two different materials connected by thermoelectric arm wires, upper and lower flexible PDMS connecting pillars, an upper PVDF layer, and a graphene thermally conductive layer. In the aforementioned fabrication method, the substrate layer and the upper PVDF film are prepared using electrospinning, resulting in low production efficiency. Furthermore, the low thermal conductivity of PVDF hinders rapid heat diffusion from the upper layer, leading to low power generation efficiency. Summary of the Invention

[0005] To address the shortcomings of the existing technologies, this invention provides a body heat power generation fabric and its preparation method. The body heat power generation fabric has advantages such as high flexibility, simple processing technology, low cost, and suitability for industrial production. This fabric that collects human body heat to generate electricity has great application value in the field of wearable electronic devices.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A body-temperature power-generating fabric includes an upper layer of high thermal conductivity insulating fabric, a lower layer of high thermal conductivity insulating fabric, a thermoelectric unit, and an insulation layer; both the upper and lower layers of high thermal conductivity insulating fabric are printed with conductive lines; the thermoelectric unit is arranged between the upper and lower layers of high thermal conductivity insulating fabric and is electrically connected to the conductive lines of both the upper and lower layers of high thermal conductivity insulating fabric; the insulation layer fills the area around the thermoelectric unit.

[0007] Preferably, the high thermal conductivity insulating fabric includes high thermal conductivity filament fabric, high thermal conductivity coated fabric, glass fiber fabric, silicon carbide fiber fabric, or ceramic fiber fabric.

[0008] Preferably, the high thermal conductivity filament fabric is prepared by adding inorganic powder with high thermal conductivity to the spinning solution to obtain high thermal conductivity fiber filaments, and the high thermal conductivity fiber filaments are woven to form the high thermal conductivity filament fabric.

[0009] Preferably, the high thermal conductivity coating fabric is prepared by adding inorganic powder with high thermal conductivity to a high thermal conductivity coating to obtain a coating slurry, and the coating slurry is processed by a coating process to form the high thermal conductivity coating fabric.

[0010] Preferably, the thermal conductivity of the high thermal conductivity insulating fabric is not less than 0.8 W / (m·K), and the resistivity is greater than 10^9 Ω·cm.

[0011] Preferably, the thermoelectric unit includes a P-type thermoelectric material and an N-type thermoelectric material, the P-type thermoelectric material and the N-type thermoelectric material are connected in series, and the P-type thermoelectric material and the N-type thermoelectric material are connected in series through the conductive lines of the upper high thermal conductivity insulating fabric and the conductive lines of the lower high thermal conductivity insulating fabric to form a thermoelectric circuit.

[0012] Preferably, the insulation layer includes a fiber membrane, fiber felt, flexible polymer film, wadding filler, or stagnant air layer.

[0013] Preferably, the thermal conductivity of the insulation layer material is less than 0.12 W / (m·K).

[0014] A method for preparing a body heat-generating fabric, the method comprising the following steps: Conductive lines are printed on the upper and lower thermally conductive insulating fabrics respectively to form an upper conductive line layer and a lower conductive line layer. P-type thermoelectric material and N-type thermoelectric material are arranged at designated positions in the lower conductive circuit layer, so that the P-type thermoelectric material and N-type thermoelectric material are electrically connected to the lower conductive circuit layer; A heat-insulating material is filled around the P-type thermoelectric material and the N-type thermoelectric material to form a heat-insulating layer; The upper layer of high thermal conductivity insulating fabric is covered on top of the insulation layer, so that the upper conductive circuit layer is electrically connected to the P-type thermoelectric material and the N-type thermoelectric material. The P-type thermoelectric material and the N-type thermoelectric material are connected in series through the upper conductive circuit layer and the lower conductive circuit layer to assemble the body temperature power generation fabric.

[0015] Preferably, the step of printing conductive lines on the upper and lower high thermal conductivity insulating fabrics respectively includes: A conductive coating screen printing process is used to prepare a rotary or flat screen printing screen according to the conductive circuit design requirements. The conductive coating containing silver powder, copper powder, aluminum powder or copper-coated silver powder is printed onto the surface of the high thermal conductivity insulating fabric through the screen printing screen to form a conductive circuit with a specific pattern. Alternatively, a hot stamping process can be used to engrave the conductive circuit design pattern onto the surface of the hot stamping machine roller, and then transfer the hot stamping paste from the hot stamping paper to the surface of the high thermal conductivity insulating fabric through gravure printing to form a conductive circuit. Alternatively, a localized chemical plating or magnetron sputtering process can be used to mask the non-conductive areas of the high thermal conductivity insulating fabric according to the conductive circuit design requirements, and chemical plating or magnetron sputtering can be performed on the exposed areas to form conductive circuits. Alternatively, conductive ink printing technology can be used to directly apply conductive ink along the designed conductive circuit path onto the surface of the highly thermally conductive insulating fabric to form a conductive circuit.

[0016] Preferably, the step of arranging the P-type thermoelectric material and the N-type thermoelectric material at designated positions in the lower conductive circuit layer includes: Using 3D printing technology, P-type thermoelectric material powder and N-type thermoelectric material powder are used as printing raw materials. They are deposited layer by layer at designated positions on the lower conductive circuit layer through the nozzle of the 3D printer to form P-type thermoelectric structures and N-type thermoelectric structures with specific geometric shapes. Alternatively, a mold assembly process can be used to hot-press P-type thermoelectric material powder and N-type thermoelectric material powder into sheet materials, and then use laser cutting to cut the sheet materials into structures of specific geometric shapes. The cut P-type structures and N-type structures are placed in a mold in an alternating manner, and the structures are fixed to the designated positions of the lower conductive circuit layer by hot pressing.

[0017] Preferably, the specific geometric shape includes a cuboid, cube, cylinder, frustum, or truncated cone.

[0018] The present invention, by adopting the above technical solution, has the following beneficial effects: 1. This invention organically combines textile processing technology with thermoelectric power generation technology, which achieves both the high efficiency of body heat power generation and ensures the comfort of the fabric itself. 2. This invention can achieve dynamic adjustability of power generation. The power generation can be adjusted simply by increasing or decreasing the number of connections between P-type and N-type materials, which can fully guarantee the power use of wearable electronic devices and is a green and environmentally friendly sustainable energy source. 3. The preparation method of the present invention is simple and is suitable for mass production while meeting high technical requirements. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the structural principle of the body temperature power generation fabric of the present invention; Figure 2 This is a three-dimensional schematic diagram of the lower layer structure of the body temperature power generation fabric of the present invention; Figure 3 This is a three-dimensional structural diagram of the heat-generating fabric of the present invention; Figure 4 This is a schematic diagram of the structure of the body temperature power generation fabric module of the present invention; Figure 5 This is a schematic diagram of the series connection of the body temperature power generation fabric module of the present invention; Figure 6 This is a schematic diagram of the body heat-generating vest of the present invention. Detailed Implementation

[0020] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0021] The working principle of this invention is as follows: Between two layers of highly thermally conductive insulating fabric, P-type and N-type thermoelectric materials are rationally selected and arranged to generate a potential difference across the two ends using the Seebeck effect. Since the power generation of a single thermoelectric unit is too low, a series of thermoelectric units are connected in series to increase the power generation, forming a thermoelectric power generation module. The generated electrical energy is directly output to wearable electronic devices via a DC / DC voltage regulator module, achieving a continuous power supply effect.

[0022] like Figure 1 As shown, the body temperature power generation fabric provided by the present invention has the following structure from bottom to top: a lower layer of high thermal conductivity insulating fabric 1, a lower layer of conductive circuit 2, a P-type thermoelectric material 3, an N-type thermoelectric material 4, a heat insulation layer 5, and an upper layer of high thermal conductivity insulating fabric 6; wherein, the P-type thermoelectric material 3 and the N-type thermoelectric material 4 are connected to the upper layer of high thermal conductivity insulating fabric 6 and the lower layer of high thermal conductivity insulating fabric 1 according to a specified circuit. Example 1

[0023] Please refer to the following: Figures 2 to 3 The body temperature power generation fabric provided in this embodiment uses a cooling fabric as the lower high thermal conductivity insulating fabric 1 and the upper high thermal conductivity insulating fabric 6. Because the cooling fabric has a high thermal conductivity and is lightweight and soft, it can improve the utilization rate of the heat energy emitted by the human body and ensure wearing comfort.

[0024] The lower conductive circuit 2 is manufactured using a conductive coating screen printing method. This processing method is mature and conducive to industrial production. Specifically, a rotary screen printing mesh is prepared according to the conductive circuit design requirements, and conductive coating containing silver powder is printed onto the surface of the cool-feeling fabric through the screen printing mesh to form a conductive circuit with a specific pattern.

[0025] The P-type thermoelectric material 3 uses Bi. 0.5 Sb 1.5 Te3 material, the N-type thermoelectric material 4 is Bi2Sb 0.5 Te 2.5 Materials. The P-type thermoelectric material powder and the N-type thermoelectric material powder are respectively hot-pressed into sheet materials. The sheet materials are then laser-cut into cuboid structures with dimensions of 1.5 mm × 1.5 mm × 2.0 mm. The cut P-type and N-type structures are placed in a mold in an alternating arrangement. The structures are fixed to the designated positions of the lower conductive circuit 2 by hot pressing, so that the P-type thermoelectric material 3 and the N-type thermoelectric material 4 are electrically connected to the lower conductive circuit 2.

[0026] The insulation layer 5 uses a flexible polymer PDMS with low thermal conductivity to encapsulate the power generation module, which ensures the flexibility of the power generation module and increases the temperature difference between the two ends of the power generation fabric, thereby improving the thermoelectric conversion efficiency. Specifically, PDMS material is filled around the P-type thermoelectric material 3 and the N-type thermoelectric material 4 to form the insulation layer 5.

[0027] The upper high thermal conductivity insulating fabric 6 is covered on top of the heat insulation layer 5. The upper high thermal conductivity insulating fabric 6 has upper conductive lines printed on its surface, so that the upper conductive lines are electrically connected to the P-type thermoelectric material 3 and the N-type thermoelectric material 4. The P-type thermoelectric material 3 and the N-type thermoelectric material 4 are connected in series through the upper conductive lines and the lower conductive lines 2 to form a thermoelectric circuit, thus assembling a body temperature power generation fabric.

[0028] According to the above process, conductive circuit areas with dimensions of 45 mm × 30 mm were printed on the cooling fabric, and 52 pairs of thermoelectric units were arranged to prepare a body-temperature power-generating fabric. When this power-generating fabric was attached tightly to the arm, at an ambient temperature of 25°C, the temperature difference between the two ends of the fabric was 6°C. Connected to a digital multimeter via leads, the test results showed that the output voltage of the power-generating fabric reached 6.7 mV. After voltage regulation, it can continuously power microelectronic devices such as ECG sensors and accelerometers. Example 2

[0029] Please refer to the following: Figures 4 to 6 The vest provided in this embodiment is made of heat-generating fabric. Specifically, a cooling fabric is used as the lower high thermal conductivity insulating fabric 1 and the upper high thermal conductivity insulating fabric 6 because it has a high thermal conductivity and is lightweight and soft, which improves the utilization rate of the heat energy emitted by the human body and ensures wearing comfort.

[0030] The lower conductive circuit 2 is manufactured using conductive ink printing. Specifically, conductive ink is directly applied to the surface of the cool-feeling fabric along the designed conductive circuit path to form the conductive circuit.

[0031] The P-type thermoelectric material 3 uses Bi. 0.5 Sb 1.5 Te3 material, the N-type thermoelectric material 4 is Bi2Sb 0.5 Te 2.5 Materials. Using 3D printing technology, P-type thermoelectric material powder and N-type thermoelectric material powder are used as printing raw materials. They are deposited layer by layer through the nozzle of the 3D printer at designated positions on the lower conductive line 2 to form a cuboid shape of P-type thermoelectric structure and N-type thermoelectric structure with a length, width and height of 1.5 mm × 1.5 mm × 2.0 mm, respectively. The P-type thermoelectric structure and the N-type thermoelectric structure are arranged alternately and electrically connected to the lower conductive line 2.

[0032] The insulation layer 5 uses a flexible polymer PDMS with low thermal conductivity to encapsulate the power generation module, which not only ensures the flexibility of the power generation fabric, but also increases the temperature difference between the two ends of the power generation fabric, thereby effectively improving the thermoelectric conversion efficiency.

[0033] The upper high thermal conductivity insulating fabric 6 is covered on top of the insulation layer 5, so that the upper conductive lines on the surface of the upper high thermal conductivity insulating fabric 6 are electrically connected to the P-type thermoelectric material 3 and the N-type thermoelectric material 4. The P-type thermoelectric material 3 and the N-type thermoelectric material 4 are connected in series through the upper conductive lines and the lower conductive lines 2 to form a thermoelectric circuit, and the body temperature power generation fabric is assembled.

[0034] According to the above process, 285 pairs of thermoelectric units were arranged in an area of ​​10 cm × 10 cm to prepare a body temperature power generation fabric module. A piece of cooling fabric with a length and width of 80 cm × 50 cm was taken, and 24 body temperature power generation fabric modules were arranged in a 6×4 array on the fabric. Each module was connected in series to form a larger body temperature power generation fabric 8. This fabric was sewn with ordinary fabric 9 to make a vest and worn on the body. When the ambient temperature was 25℃, the temperature difference between the two ends of the fabric was 6℃. It was connected to a digital multimeter through lead wire 7. The test results showed that the output voltage of the power generation fabric reached 1.2 V. After voltage regulation, it can not only continuously power microelectronic devices such as ECG sensors and accelerometers, but also charge mobile phones and power banks through USB interface.

[0035] The above embodiments are only used to illustrate the present invention. The structure, connection method and manufacturing process of each component can be varied. Any modifications, equivalent substitutions and improvements made on the basis of the technical solution of the present invention are included within the protection scope of the present invention.

Claims

1. A body-temperature-generating fabric, characterized in that, The body temperature power generation fabric includes an upper layer of high thermal conductivity insulating fabric, a lower layer of high thermal conductivity insulating fabric, a thermoelectric unit, and an insulation layer; both the upper and lower layers of high thermal conductivity insulating fabric are printed with conductive lines; the thermoelectric unit is arranged between the upper and lower layers of high thermal conductivity insulating fabric, and is electrically connected to the conductive lines of the upper and lower layers of high thermal conductivity insulating fabric; the insulation layer fills the area around the thermoelectric unit.

2. The body temperature-generating fabric according to claim 1, characterized in that, The high thermal conductivity insulating fabric includes high thermal conductivity filament fabric, high thermal conductivity coated fabric, glass fiber fabric, silicon carbide fiber fabric, or ceramic fiber fabric.

3. The body temperature power generation fabric according to claim 2, characterized in that, The high thermal conductivity filament fabric is obtained by adding inorganic powder with high thermal conductivity to the spinning solution to obtain high thermal conductivity fiber filaments, and the high thermal conductivity fiber filaments are woven to form the high thermal conductivity filament fabric.

4. The body heat-generating fabric according to claim 2, characterized in that, The high thermal conductivity coated fabric is prepared by adding inorganic powder with high thermal conductivity to a high thermal conductivity coating to obtain a coating slurry, and the coating slurry is processed by a coating process to form the high thermal conductivity coated fabric.

5. The body heat-generating fabric according to claim 1, characterized in that, The thermoelectric unit includes a P-type thermoelectric material and an N-type thermoelectric material. The P-type thermoelectric material and the N-type thermoelectric material are connected in series. The P-type thermoelectric material and the N-type thermoelectric material are connected in series through the conductive lines of the upper high thermal conductivity insulating fabric and the conductive lines of the lower high thermal conductivity insulating fabric to form a thermoelectric circuit.

6. The body heat-generating fabric according to claim 1, characterized in that, The insulation layer includes a fiber membrane, fiber felt, flexible polymer film, flocculent filler, or stagnant air layer.

7. A method for preparing a body-heat-generating fabric, characterized in that, The preparation method includes the following steps: Conductive lines are printed on the upper and lower thermally conductive insulating fabrics respectively to form an upper conductive line layer and a lower conductive line layer. P-type thermoelectric material and N-type thermoelectric material are arranged at designated positions in the lower conductive circuit layer, so that the P-type thermoelectric material and N-type thermoelectric material are electrically connected to the lower conductive circuit layer; A heat-insulating material is filled around the P-type thermoelectric material and the N-type thermoelectric material to form a heat-insulating layer; The upper layer of high thermal conductivity insulating fabric is covered on top of the insulation layer, so that the upper conductive circuit layer is electrically connected to the P-type thermoelectric material and the N-type thermoelectric material. The P-type thermoelectric material and the N-type thermoelectric material are connected in series through the upper conductive circuit layer and the lower conductive circuit layer to assemble the body temperature power generation fabric.

8. The preparation method according to claim 7, characterized in that, The step of printing conductive lines on the upper and lower layers of high thermal conductivity insulating fabric includes: A conductive coating screen printing process is used to prepare a rotary or flat screen printing screen according to the conductive circuit design requirements. The conductive coating containing silver powder, copper powder, aluminum powder or copper-coated silver powder is printed onto the surface of the high thermal conductivity insulating fabric through the screen printing screen to form a conductive circuit with a specific pattern. Alternatively, a hot stamping process can be used to engrave the conductive circuit design pattern onto the surface of the hot stamping machine roller, and then transfer the hot stamping paste from the hot stamping paper to the surface of the high thermal conductivity insulating fabric through gravure printing to form a conductive circuit. Alternatively, a localized chemical plating or magnetron sputtering process can be used to mask the non-conductive areas of the high thermal conductivity insulating fabric according to the conductive circuit design requirements, and chemical plating or magnetron sputtering can be performed on the exposed areas to form conductive circuits. Alternatively, conductive ink printing technology can be used to directly apply conductive ink along the designed conductive circuit path onto the surface of the highly thermally conductive insulating fabric to form a conductive circuit.

9. The preparation method according to claim 7, characterized in that, The step of arranging P-type and N-type thermoelectric materials at designated locations in the lower conductive circuit layer includes: Using 3D printing technology, P-type thermoelectric material powder and N-type thermoelectric material powder are used as printing raw materials. They are deposited layer by layer at designated positions on the lower conductive circuit layer through the nozzle of the 3D printer to form P-type thermoelectric structures and N-type thermoelectric structures with specific geometric shapes. Alternatively, a mold assembly process can be used to hot-press P-type thermoelectric material powder and N-type thermoelectric material powder into sheet materials, and then use laser cutting to cut the sheet materials into structures of specific geometric shapes. The cut P-type structures and N-type structures are placed in a mold in an alternating manner, and the structures are fixed to the designated positions of the lower conductive circuit layer by hot pressing.

10. The preparation method according to claim 9, characterized in that, The specific geometric shape includes a cuboid, cube, cylinder, frustum, or truncated cone.

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