Thermoelectric power generation module and manufacturing method thereof

Abstract

To provide a thermoelectric power generation module capable of achieving both heat insulation and power generation efficiency.SOLUTION: A thermoelectric power generation module (1) includes a thermoelectric generation element (20) that includes a thermoelectric material portion (21) that generates an electromotive force corresponding to the temperature difference between a first main surface (11) and a second main surface (12) of a heat insulating member (10) having a thermal conductivity of 0.2 Wm-1K-1 or less and is configured to generate a current in a desired direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a thermoelectric power generation module and a method for manufacturing a thermoelectric power generation module. [Background technology]

[0002] Thermoelectric power generation technology is a technology that directly converts thermal energy into electrical energy. The magnitude of the thermoelectromotive force depends on the temperature difference between both sides of the thermoelectric conversion material. A known technology for implementing such thermoelectric power generation is a thermoelectric power generation module that has a heat insulating member installed on a heat source and a thermoelectric power generation unit that is disposed in the heat insulating member so as to penetrate the heat insulating member in the thickness direction and is electrically conductive (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-110157 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional thermoelectric power generation modules, the thermoelectric power generation portion that penetrates the thermal insulation member can also serve as a heat release path. This can result in insufficient thermal insulation or insufficient power generation efficiency. Thus, conventional thermoelectric power generation modules have room for improvement in terms of achieving both thermal insulation and power generation efficiency.

[0005] An object of the present invention is to provide a thermoelectric power generation module that can achieve both thermal insulation and power generation efficiency. [Means for solving the problem]

[0006] In order to solve the above problems, a thermoelectric power generation module according to one aspect of the present invention has a first main surface and a second main surface, and has a thermal conductivity of 0.2 Wm -1 K -1and a thermoelectric power generation element that includes a thermoelectric material portion disposed between the first main surface and the second main surface of the thermal insulation member and that generates an electromotive force according to a temperature difference between the first main surface side and the second main surface side, and that is configured to generate a current in a desired direction.

[0007] In order to solve the above-mentioned problems, a method for manufacturing a thermoelectric power generation module according to one aspect of the present invention includes the steps of: forming first conductive portions by intermittently applying or impregnating insulating fibers with a first thermoelectric material; intermittently applying or impregnating the fibers with a second thermoelectric material or a conductive material to form second conductive portions that connect the first thermoelectric material portions; and -1 K -1 and a step of stitching the fibers together into an insulating member having the following thermal conductivity, and arranging the first conductive portions and the second conductive portions on the insulating member so that the first conductive portions and the second conductive portions alternately cross between the first and second main surfaces of the insulating member, wherein the first conductive portions and the second conductive portions are configured to generate an electric current in one direction along the length of the fibers. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a thermoelectric power generation module that can achieve both heat insulation and power generation efficiency. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view schematically illustrating a configuration of a thermoelectric power generation module according to one embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing the current-voltage characteristics between a heat source (60° C.) and the outside air in the thermoelectric power generation module of Example 1 of the present invention. [Figure 3] FIG. 2 is a diagram showing the power-voltage characteristics between a heat source (60° C.) and the outside air in the thermoelectric power generation module according to Example 1 of the present invention. [Figure 4] FIG. 10 is a diagram showing the current-voltage characteristics between a heat source (100° C.) and the outside air in the thermoelectric power generation module according to Example 2 of the present invention. [Figure 5]FIG. 10 is a diagram showing the power-voltage characteristics between a heat source (100° C.) and outside air in the thermoelectric power generation module according to Example 2 of the present invention. [Figure 6] FIG. 10 is a diagram showing the calculation results of the temperature difference between both ends of the thermoelectric material part depending on the thermal conductivity of the conductive part. [Figure 7] 10 is a diagram showing the calculation results of the electromotive force of a thermoelectric power generation module depending on the thermal conductivity of the conductive part. FIG. [Figure 8] FIG. 4 is a diagram showing the temperature on the first main surface side when the thermoelectric power generation modules of Examples 1 and 2 of the present invention are heated from the second main surface side. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Thermoelectric power generation module] A thermoelectric power generation module according to an embodiment of the present invention includes a heat insulating member and a thermoelectric power generation element.

[0011] [Insulation materials] The thermal insulating member is a member having thermal insulating properties and has a first main surface and a second main surface, one of which is positioned relative to or in contact with a heat source, and the other of which faces the surrounding environment of the heat source.

[0012] The shape of the heat insulating member may be determined appropriately depending on various conditions, such as the shape of the heat source on which the thermoelectric power generation module of the embodiment of the present invention is installed, the temperature of the heat source, and the insulating effect required of the thermoelectric power generation module. Examples of the shape of the heat insulating member include a flat plate shape and a cylindrical shape. If the shape of the heat insulating member is flat, the first main surface is the surface visible when the heat insulating member is viewed from above, and the second main surface is the surface opposite the first main surface in the thickness direction of the heat insulating member. If the shape of the heat insulating member is cylindrical, the first main surface is one of the inner circumferential surface and the outer circumferential surface, and the second main surface is the other of the inner circumferential surface and the outer circumferential surface. The shape of the heat insulating member is preferable from the viewpoint of sufficiently increasing the degree of freedom and ease of installation on the heat source.

[0013] The insulating member can be appropriately selected from among ordinary insulating members used for insulating heat sources. From the viewpoint of flexibility in installation on the heat source, the insulating member preferably has deformable flexibility. Examples of materials for the insulating member include glass wool, rock wool, cellulose fiber, urethane foam, and phenol foam.

[0014] If the thermal conductivity of the heat insulating material is too high, the heat insulating property may be insufficient and the power generation efficiency may be insufficient. From the viewpoint of sufficiently increasing the heat insulating property, the heat insulating material has a thermal conductivity of 0.2 Wm -1 K -1 The thermal conductivity of the heat insulating material is 0.15 Wm -1 K -1 From the viewpoint of sufficiently increasing both the heat insulating property and the power generation efficiency, the thermal conductivity of the heat insulating member is more preferably 0.15 Wm -1 K -1 Preferably, it is less than 0.1 Wm -1 K -1 More preferably, it is:

[0015] The thermal conductivity of the heat insulating member can be measured by a known measurement method, such as the Guarded Hot Plate (GHP) method. The thermal conductivity of the heat insulating member can be adjusted appropriately depending on the type of heat insulating member.

[0016] The size of the heat insulating member may be determined appropriately depending on various factors, such as the size of the heat source and the volume and shape of the space surrounding the heat source. The distance from the first to second main surfaces of the heat insulating member is preferably 350 mm or less, more preferably 100 mm or less, from the viewpoints of flexibility in installation on the heat source and thermal insulation. Furthermore, the distance from the first to second main surfaces of the heat insulating member is preferably sufficiently small, from the viewpoint of increasing flexibility in installation on the heat source, for example, preferably 50 mm or less, more preferably 30 mm or less. Furthermore, the distance from the first to second main surfaces of the heat insulating member is preferably 3 mm or more, from the viewpoint of achieving sufficient thermal insulation of the heat insulating member. The "distance from the first to second main surfaces of the heat insulating member" may be a typical numerical value representing the distance between the first and second main surfaces of the heat insulating member, such as thickness.

[0017] [Thermoelectric power generation element] <Thermoelectric materials department> The thermoelectric power generating element includes a thermoelectric material portion. The thermoelectric material portion is a portion made of a material that generates an electromotive force in response to a temperature difference. In an embodiment of the present invention, the thermoelectric material portion is disposed between the first main surface and the second main surface of the heat insulating member. Therefore, the thermoelectric material portion generates an electromotive force in response to the temperature difference between the first main surface side and the second main surface side.

[0018] From the viewpoint of generating the maximum temperature difference and increasing power generation efficiency, the thermoelectric material portion preferably penetrates the heat insulating member between the first and second main surfaces. "The thermoelectric material portion penetrates the heat insulating member" refers to a state in which a portion of a single thermoelectric material portion located within the heat insulating member is exposed on the first main surface of the heat insulating member, and another portion is exposed on the second main surface.

[0019] The thermoelectric material unit may be arranged in the heat insulating member so as to obtain a temperature difference sufficient for generating electricity, and may be arranged, for example, so as to move back and forth between the vicinity of the first principal surface and the vicinity of the second principal surface in the thickness direction of the heat insulating member. The thermoelectric material unit may be composed of only a thermoelectric material, or may include other structures as long as the effects of the embodiments of the present invention can be obtained.

[0020] <Thermoelectric materials> The thermoelectric material section contains a thermoelectric material that generates an electromotive force according to the temperature gradient. To improve the power generation efficiency of the thermoelectric power generation module, the Seebeck coefficient of the thermoelectric material is set to an absolute value of 10 μVK. -1 That is, 10μVK or more -1 or above -10μVK -1 It is preferable that the absolute value is 15 μVK or less. -1 That is, 15μVK or more -1 or above -15μVK -1 More preferably, it is:

[0021] The higher the Seebeck coefficient of a thermoelectric material, the better from the viewpoint of power generation efficiency, but its upper limit may be a general theoretical value or a value appropriate for the material. For example, the upper limit of the Seebeck coefficient of a thermoelectric material is a general theoretical value of 1 mVK in absolute value. -1 Below (1mVK -1 Above or -1mVK -1 or less), or for certain organic thermoelectric materials, an absolute value of 100 mVK -1 Below (100mVK -1 or above -100mVK -1 In recent years, materials exhibiting high Seebeck coefficients have been discovered, and unknown materials exhibiting even higher Seebeck coefficients may also be applied within the scope in which the effects of the embodiments of the present invention can be obtained.

[0022] The upper limit of the Seebeck coefficient of the thermoelectric material can be determined appropriately depending on the intended use of the thermoelectric power generation module. For example, for the power supply of a sensor, the upper limit is set to 10 μVK in absolute value. -1 Less than 10μVK -1 Less than or equal to -10μVK -1 It may be more than that.

[0023] The Seebeck coefficient of a thermoelectric material may be a catalog value, a literature value, an actually measured value, or a calculated value. The Seebeck coefficient of a thermoelectric material can be measured by known techniques, for example, by applying a temperature difference to a sample and measuring the electromotive force with a voltmeter. The Seebeck coefficient of a thermoelectric material can also be adjusted depending on the type of thermoelectric material.

[0024] The conductivity of the thermoelectric material is set to 0.5 Scm in order to increase the power generation efficiency of the thermoelectric power generation module. -1 It is preferable that it is 5Scm or more. -1 It is more preferable that the conductivity of the thermoelectric material is 1×10 or more. The conductivity of the thermoelectric material can be appropriately determined depending on the configuration of the thermoelectric power generation element. If the conductivity of the thermoelectric material is too high, the thermal conductivity in the thermoelectric material portion tends to be high, and it may become difficult to extract the generated electric power sufficiently. From this viewpoint, the conductivity of the thermoelectric material is set to, for example, 1×10 5 Scm -1 or less, or 3000 Scm -1 It may be the following:

[0025] The electrical conductivity of a thermoelectric material can be determined using a known measuring device capable of simultaneously measuring the Seebeck coefficient and electrical conductivity of a thermoelectric material. The electrical conductivity of a thermoelectric material can also be adjusted by changing the type of thermoelectric material.

[0026] The thermoelectric material can be suitably selected from known thermoelectric materials preferably having the above-mentioned properties, and may be inorganic or organic. The thermoelectric material may be p-type or n-type, and the Seebeck coefficient of the thermoelectric material may be positive or negative. One or more types of thermoelectric material may be used.

[0027] Examples of thermoelectric materials include conductive polymers and carbon materials, which are suitable for application to flexible structures and are preferred from the viewpoint of preventing the thermoelectric material from falling off from the thermoelectric material section.

[0028] Examples of conductive polymer materials include polythiophene-based polymers, polyaniline-based polymers, polypyrrole-based polymers, polyphenylene-based polymers, polyphenylene vinylene-based polymers, polyacetylene-based polymers, polyacene-based polymers, and polythienylene vinylene-based polymers. An example of a polythiophene-based polymer is poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrene sulfonate (PSS). This specific example of a polythiophene-based polymer is also referred to as "PEDOT:PSS."

[0029] Examples of the carbon material include carbon nanotubes, graphene, graphene nanoplatelets, graphite, graphene oxide, reduced graphene oxide, carbon black, ketjen black, fullerene, and fullerene derivatives.

[0030] [Electrical configuration of thermoelectric power generation element] The thermoelectric generating element is configured to generate a current in a desired direction. Such an electrical configuration of the thermoelectric generating element can be determined appropriately depending on the type of thermoelectric material and the electrical connection configuration of the thermoelectric material portion.

[0031] <Conductive part> In order to enhance the versatility of the electrical configuration of the thermoelectric power generation element, it is preferable that the thermoelectric power generation element further includes a conductive part electrically connected to the thermoelectric material part in addition to the thermoelectric material part. The conductive part can be made of a conductive material.

[0032] The thermal conductivity of the conductive material must be 50 Wm -1 K -1 Preferably less than 30Wm -1 K -1 It is more preferable that the thermal conductivity of the conductive material is less than 0.03 Wm. Generally, conductive materials tend to have thermal conductivity. From this viewpoint, the thermal conductivity of the conductive material is preferably as small as possible, but does not have to be zero. For example, -1 K -1 It may be more than that.

[0033] The thermal conductivity of the conductive material can be measured by known measurement techniques, such as a steady-state method or a laser flash method, and can be adjusted by changing the type of conductive material.

[0034] The Seebeck coefficient of the conductive material can be determined appropriately depending on the Seebeck coefficient of the thermoelectric material. From the viewpoint of realizing a better current flow and increasing power generation efficiency, the Seebeck coefficient of the conductive material is set to 10 μVK if the sign of the Seebeck coefficient of the thermoelectric material is positive. -1 It is preferable that the Seebeck coefficient of the thermoelectric material is less than or equal to -10 μVK if the sign of the Seebeck coefficient is negative. -1 It is preferable that this is equal to or greater than this.

[0035] When the sign of the Seebeck coefficient of a thermoelectric material is positive, the Seebeck coefficient of a conductive material is 10 μVK. -1 It is acceptable if it is smaller than this, for example, -10μVK. -1 In addition, if the Seebeck coefficient of the thermoelectric material has a negative sign, the Seebeck coefficient of the conductive material may be large, for example, 10 μVK. -1 This is due to the direction of the electromotive force generated between the conductive portion and the thermoelectric material portion.

[0036] In a thermoelectric power generation element in which a thermoelectric material portion and a conductive portion are adjacent to each other, if the Seebeck coefficients of the thermoelectric material and the conductive material have the same sign, the electromotive forces in each portion will be opposite in direction. Therefore, the electromotive force generated in the thermoelectric material portion will be canceled out by the electromotive force generated in the conductive portion. When the Seebeck coefficient of the thermoelectric material is positive, if the Seebeck coefficient of the conductive material is sufficiently smaller than that of the thermoelectric material, the above-mentioned cancellation effect will be reduced, or the electromotive forces will be in the same direction. Therefore, good power generation characteristics will be achieved. Similarly, when the Seebeck coefficient of the thermoelectric material is negative, if the Seebeck coefficient of the conductive material is sufficiently larger than that of the thermoelectric material, good power generation characteristics will be achieved.

[0037] The boundary value relative to one of the boundary values of the Seebeck coefficient of the conductive material (for example, the lower limit value relative to the upper limit value) may be appropriately determined within a range in which the effects of the embodiment of the present invention can be obtained and within a range that can be realized by the conductive material. For example, the upper limit value of the Seebeck coefficient of the conductive material is 100 μVK. -1 It can be less than or equal to -100μVK. -1 It may be more than that.

[0038] Furthermore, from the viewpoint of reducing the above-mentioned cancellation of electromotive forces, the ratio S2 / S1 of the Seebeck coefficient S2 of the conductive material to the Seebeck coefficient S1 of the thermoelectric material is determined appropriately depending on the signs of these coefficients. For example, when S1 and S2 have the same sign, S2 / S1 is preferably 0.0001 to 1 from the above viewpoint. When S1 and S2 have different signs, S2 / S1 is preferably -10 to -0.0001 from the above viewpoint.

[0039] The Seebeck coefficient of the conductive material can be measured by the same method as that for the thermoelectric material described above. The Seebeck coefficient of the conductive material can also be adjusted by changing the type of conductive material.

[0040] The conductive material may be one or more materials having sufficient conductivity. Examples of the conductive material include metals, conductive polymers, and carbon materials. Such conductive materials are suitable for flexible structures and are preferred from the viewpoint of preventing the thermoelectric material from falling off from the thermoelectric material section.

[0041] Examples of the metal include silver, aluminum, copper, nickel, titanium, and alloys containing any of these metals. The conductive material containing a metal may be a metallic member such as a wire, or may be a metal paste containing metal particles and a dispersion medium or a binder resin. Examples of the conductive polymer and carbon material include the components exemplified in the thermoelectric material.

[0042] The Seebeck coefficient and electrical conductivity generally vary depending on the crystal quality, crystal purity, or carrier doping for controlling electrical conductivity, even for the same material. Therefore, even if a thermoelectric material and a conductive material are made of the same material, they can be distinguished from each other. For example, even for the same material, a conductive material can be defined as one with a smaller absolute value of the Seebeck coefficient and a larger electrical conductivity, while a thermoelectric material can be defined as one with a larger absolute value of the Seebeck coefficient and a smaller electrical conductivity.

[0043] <Electrical connection type> The p-type thermoelectric material generates a current flowing from the high temperature side to the low temperature side, and the n-type thermoelectric material generates a current flowing from the low temperature side to the high temperature side. The conductive portion can electrically connect the thermoelectric materials. The thermoelectric power generation module according to the embodiment of the present invention can adopt various electrical configurations that generate a current in a desired direction by combining these components.

[0044] In the case of a thermoelectric power generation element in which thermoelectric material parts are connected in series, for example, p-type thermoelectric material parts and n-type thermoelectric material parts are alternately connected in series to form a thermoelectric power generation element that generates current in a desired direction.

[0045] The p-type thermoelectric material sections and the n-type thermoelectric material sections may be alternately connected in series via conductive sections, which is preferable from the viewpoint of adjusting the positions of the thermoelectric material sections to desired positions in the thickness direction of the heat insulating member.

[0046] Alternatively, the thermoelectric power generation element may include a series circuit in which thermoelectric material sections, each including either p-type or n-type thermoelectric material sections, and conductive sections are alternately connected, and the thermoelectric material sections and conductive sections are arranged alternately in the planar direction of the first or second main surface of the thermal insulating member, between the first and second main surfaces. This connection configuration results in a thermoelectric power generation element having a repeating unit of p-type thermoelectric material sections and conductive sections, a thermoelectric power generation element having a repeating unit of n-type thermoelectric material sections and conductive sections, or a thermoelectric power generation element having a repeating unit of p-type thermoelectric material sections, conductive sections, n-type thermoelectric material sections, and conductive sections. Such a thermoelectric power generation element is preferable from the viewpoint of achieving sufficiently high voltage power generation with a simple configuration. Furthermore, when the thermoelectric power generation element is constructed using a single thermoelectric material, this thermoelectric power generation element is suitable for fully utilizing the power generation efficiency of the thermoelectric material.

[0047] Alternatively, the thermoelectric power generation element may be configured with either p-type or n-type thermoelectric material sections arranged along the thickness direction of the thermal insulation member, a first conductive section electrically connecting one ends of the thermoelectric material sections, and a second conductive section electrically connecting the other ends of the thermoelectric material sections. This type of connection results in a parallel circuit of p-type or n-type thermoelectric material sections that crosses the thermal insulation member. This type of thermoelectric power generation element is preferable from the perspective of achieving sufficiently large current generation with a simple configuration. In this case, the conductive section may be formed in a linear shape connecting the ends of the thermoelectric material sections, or in a film shape that covers the entire first or second main surface of the thermal insulation member.

[0048] <Preferable form of thermoelectric power generation element> The thermoelectric power generation element preferably has a flexible and deformable shape, from the viewpoint of increasing the versatility of the thermoelectric power generation module for use with various types of heat sources.Furthermore, the thermoelectric power generation element preferably has a flexible fibrous shape, from the viewpoint of suppressing damage to the thermoelectric power generation element due to deformation of the thermoelectric power generation module.

[0049] Such a thermoelectric power generation element may include insulating fibers. The fibers may serve as carriers for the thermoelectric material portion and the conductive portion. The fibers may be natural or synthetic. From the viewpoints of insulation and flexibility, a preferred example of the fibers is cotton yarn.

[0050] In the above embodiment, the thermoelectric material section is formed by carrying a thermoelectric material that generates an electromotive force in response to a temperature gradient on the fibers. Furthermore, when the thermoelectric power generation element of this embodiment further includes a conductive section, the conductive section is formed by carrying a conductive material on the fibers. Carrying the thermoelectric material section on the fibers or carrying the conductive section on the fibers is preferable from the viewpoint of preventing damage to the thermoelectric power generation element due to deformation of the thermoelectric power generation module. The thermoelectric material section and the conductive section can be carried on the fibers by known techniques, and may be, for example, by applying or immersing the thermoelectric material section in a paint and drying it, by physically adsorbing the thermoelectric material to the fibers, or by chemically adsorbing the thermoelectric material to the fibers.

[0051] [Thermal properties] In an embodiment of the present invention, the thermal conductivity between the first and second main surfaces of the heat insulating member of the thermoelectric power generation module (hereinafter simply referred to as the "thermal conductivity of the thermoelectric power generation module") is 50 Wm -1 K -1 From the above viewpoint, the lower the thermal conductivity, the better. -1 K -1 It is more preferable that it is less than 30Wm -1 K -1 It is even more preferable that:

[0052] The thermal conductivity of the thermoelectric power generation module can be measured by known techniques such as the steady-state method or the laser flash method, as with conductive materials. The thermal conductivity of the thermoelectric power generation module may also be a calculated value obtained by computer simulation.

[0053] The thermal conductivity of a thermoelectric power generation module is determined between a portion on the heat source side and a portion on the opposite side that is most thermally affected by the heat source. For example, when the thermoelectric material portion is arranged so as to cross the thermal insulating member, the thermal conductivity of the thermoelectric power generation module is the thermal conductivity between a portion of the thermoelectric power generation element exposed on the first main surface side and a portion of the thermoelectric power generation element exposed on the second main surface side. When the thermoelectric power generation element is not exposed on the first or second main surface of the thermal insulating member, the thermal conductivity of the thermoelectric power generation module is the thermal conductivity between a portion of the first main surface of the thermal insulating member closest to the thermoelectric power generation element and a portion of the second main surface of the thermal insulating member closest to the thermoelectric power generation element.

[0054] The thermal conductivity of a thermoelectric power generation module can be adjusted appropriately by changing the configuration of the thermoelectric power generation element. The thermal conductivity of a thermoelectric power generation module is usually greater than that of a thermal insulating member. This is because the thermoelectric material portions or conductive portions arranged in a direction transverse to the thermal insulating member act as heat paths. Therefore, the thermal conductivity of a thermoelectric power generation module tends to be lowered by using a material with lower thermal conductivity for the thermoelectric material or conductive material. In addition, the thermal conductivity of a thermoelectric power generation module tends to be lowered by reducing the number of thermoelectric material portions or conductive portions arranged per unit area on the first or second principal surface (increasing the spacing in the plane direction).

[0055] The "number of thermoelectric material portions or conductive portions arranged per unit area on the first or second principal surface" can be determined from the viewpoint of processability when manufacturing the thermoelectric power generation module, in addition to the thermal conductivity of the thermoelectric power generation module. Generally, the greater the number of such arranged portions per unit area, the greater the difficulty of processing, and the smaller the number of such arranged portions per unit area, the less difficult the processing tends to be. From the viewpoint of processability and the control of thermal conductivity, the number of thermoelectric material portions or conductive portions arranged per unit area on the first or second principal surface is set to 0.003 portions / cm. 2 It may be more than 50 pieces / cm 2From the above viewpoint, the length of the thermoelectric material portion or conductive portion on the first or second principal surface side (for example, the length of the portion exposed on the principal surface) may be appropriately determined within the range of, for example, 0.07 to 20 cm.

[0056] In the embodiments of the present invention, the balance between the thermal insulation properties and the power generation efficiency of the thermoelectric power generation module should be determined appropriately depending on the application of the thermoelectric power generation module. For example, if the application of the thermoelectric power generation module as a thermal insulator is to keep a portion heated by steam warm, and the application of the thermoelectric power generation module as a power generation device is to power a sensor, the materials and configuration can be determined appropriately so as to achieve the thermal insulation properties and power generation efficiency appropriate for these applications.

[0057] [Method of manufacturing thermoelectric power generation modules] The thermoelectric power generation module according to the embodiment of the present invention can be manufactured appropriately depending on the properties and shape of the thermoelectric power generation element. The thermoelectric power generation module according to the embodiment of the present invention can be manufactured by a method including a step of forming, in a thermal insulation member, a thermoelectric material portion that crosses the thermal insulation member in the thickness direction of the thermal insulation member, and further including, as necessary, a step of forming a conductive portion that is electrically connected to the thermoelectric power generation portion.

[0058] In the method for manufacturing a thermoelectric power generation module, the step of forming the thermoelectric material section may be performed before the step of forming the conductive section, after the step of forming the conductive section, or simultaneously with the step of forming the conductive section. The step of forming the thermoelectric material section may be, for example, a step of inserting a rod-shaped thermoelectric material section into a thermal insulating member, or a step of embedding the thermoelectric material section into the thermal insulating member. Furthermore, the step of forming the thermoelectric material section may be a step of forming thermoelectric material sections intermittently on a fabric and sewing the fabric into the thermal insulating member.

[0059] The step of forming the conductive portion may be a step of connecting the thermoelectric material portions together, or a step of applying a conductive paint to the main surface of the heat insulating member to form a coating film that connects the ends of the thermoelectric material portions exposed on the main surface, and drying the coating film to form the conductive portion.The step of forming the conductive portion may be a step of immersing the thermoelectric material portions intermittently formed in a fabric sewn into the heat insulating member in a paint of a conductive material in the portions between the thermoelectric material portions, and drying the paint to form the conductive portion.

[0060] Alternatively, the method for manufacturing the thermoelectric power generation module may include the steps of preparing a thermoelectric power generation element and disposing the thermoelectric power generation element in a thermal insulation member. For example, the method for manufacturing the thermoelectric power generation module may include the steps of intermittently coating or impregnating insulating fibers with a first thermoelectric material to form first conductive portions, intermittently coating or impregnating the fibers with a second thermoelectric material or a conductive material to form second conductive portions connecting the first thermoelectric material portions, and stitching the fibers through the thermal insulation member to dispose the first conductive portions and the second conductive portions in the thermal insulation member so that the first conductive portions and the second conductive portions alternately cross between a first main surface and a second main surface of the thermal insulation member.

[0061] The step of forming the first conductive portion can be performed by applying a paint of the thermoelectric material to the fibers or by immersing a part of the fibers in the paint and then drying the paint. The first conductive portion corresponds to the thermoelectric material portion described above.

[0062] The step of forming the second conductive portion can be carried out in the same manner as the step of forming the first conductive portion. If paint made of a thermoelectric material is used in the step of forming the second conductive portion, the second conductive portion corresponds to the thermoelectric material portion described above. If paint made of a conductive material is used in the step of forming the second conductive portion, the second conductive portion corresponds to the conductive portion described above.

[0063] The first conductive portion and the second conductive portion can be formed by applying or immersing the fibers in a paint that corresponds to various conditions, such as the type of thermoelectric material, the pitch of the thermoelectric material portion to be formed, and the position and pitch of the conductive portion to be formed.

[0064] The above-described steps of forming the first conductive portion and the second conductive portion enable the fabrication of a thermoelectric power generation element in which a thermoelectric material or a conductive material is carried by a fiber. This thermoelectric power generation element can be handled in the same way as a fiber, and by appropriately sewing it through a thermal insulation member, it can become a series of thermoelectric power generation elements in which the thermoelectric power generation portion and the conductive portion are appropriately arranged in the thermal insulation member.

[0065] When the first conductive portion and the second conductive portion are configured to generate a current in one direction along the length of the fiber, a thermoelectric power generation module that generates thermoelectric power in the thickness direction of the thermal insulation member can be obtained by sewing the fibers of such thermoelectric power generation elements into a thermal insulation member. Because the fibers are insulating, they do not substantially affect the thermal conductivity and electrical conductivity of the thermoelectric power generation elements. This makes it possible to produce a thermoelectric power generation module that achieves both thermal insulation and power generation efficiency, and is also preferable from the perspective of preventing damage to the thermoelectric power generation elements due to deformation of the thermoelectric power generation module.

[0066] The thermal conductivity between the first and second principal surfaces of the thermoelectric power generation module is 50 Wm -1 K -1 From the viewpoint of sufficiently enhancing the thermal insulation of the thermoelectric power generation module, it is preferable that the thermal conductivity is below 100%. The thermal conductivity tends to be reduced by adjusting the types of conductive material and electrically conductive material, and the spacing (pitch) of the thermoelectric material portions or conductive portions that cross the thermal insulation member, as well as by increasing the porosity of the thermoelectric material portions and conductive portions.

[0067] The method for manufacturing a thermoelectric power generation module according to an embodiment of the present invention may further include other steps in addition to those described above, as long as the effects of this embodiment can be obtained.

[0068] [Explanation of specific form] A thermoelectric power generation module according to one embodiment of the present invention will now be described with reference to the drawings, in which: Figure 1 is a cross-sectional view schematically illustrating the configuration of a thermoelectric power generation module according to one embodiment of the present invention.

[0069] 1, the thermoelectric power generation module 1 includes a heat insulating member 10 and a thermoelectric power generation element 20. The heat insulating member 10 is, for example, a sheet-like member made of glass wool with a thickness D2, and includes a first main surface 11 and a second main surface 12 on the opposite side. In addition to heat insulating properties, the heat insulating member 10 is flexible and deformable.

[0070] The thermoelectric power generation element 20 is a linear element. The thermoelectric power generation element 20 has a thermoelectric material portion 21, a conductive portion 22, and an overlapping portion 23. The thermoelectric power generation element 20 includes insulating fibers such as cotton thread, and the thermoelectric material portion 21, the conductive portion 22, and the overlapping portion 23 are formed by carrying a thermoelectric material and a conductive material on the fibers. The overlapping portion 23 is an overlapping portion between the thermoelectric material portion 21 and the conductive portion 22, and therefore, conduction between the thermoelectric material portion 21 and the conductive portion 22 is more reliable than in a case where the overlapping portion 23 is not included.

[0071] For example, the thermoelectric material section 21 is formed by immersing the fibers in a paint of a p-type thermoelectric material such as PEDOT:PSS and drying it. The conductive section 22 is formed by immersing the fibers in a metal slurry such as a metal paste, or by applying a metal slurry to the fibers and drying it. The overlapping section 23 is formed by fabricating the conductive section 22 so that it overlaps the end of the thermoelectric material section 21.

[0072] The thermoelectric power generation element 20 is flexible because it has a thermoelectric material portion 21, a conductive portion 22, and an overlapping portion 23 supported by fibers. The thermoelectric power generation element 20 is disposed in the heat insulating member 10 by sewing it to the heat insulating member 10 so as to move back and forth between the first main surface 11 and the second main surface 12 of the heat insulating member 10.

[0073] More specifically, the thermoelectric material portions 21 are arranged at positions that traverse the heat insulating member 10 in the thickness direction. The conductive portions 22 are arranged at positions adjacent to the thermoelectric material portions 21 in the planar direction and at positions that traverse the heat insulating member 10 in the thickness direction. A plurality of portions 24 with a length D1, each including the conductive portions 22 and overlapping portions 23, are arranged intermittently on the first main surface 11 or the second main surface 12 of the heat insulating member 10, and the thermoelectric material portions 21 and conductive portions 22 that are adjacent in the planar direction are connected to each other by the portions 24.

[0074] The thermoelectric power generation module 1 is used as a heat insulator for a heat source and generates an electromotive force in response to the temperature difference between the first main surface 11 and the second main surface 12. For example, if the thermoelectric power generation module 1 is installed on a heat source so that the second main surface 12 surrounds the heat source, the second main surface 12 becomes the high-temperature side and the first main surface 11 becomes the low-temperature side. If the thermoelectric material portion 21 is p-type, an electromotive force is generated between points a and b in response to the temperature difference, and a current flows from point a to point b. Therefore, the current flows to the left of the paper in the drawing. Meanwhile, the heat insulating member 10 of the thermoelectric power generation module 1 prevents the heat from the heat source from being released to the outside. In this way, the heat source is kept warm by the thermoelectric power generation module 1.

[0075] Other Embodiments In the embodiment of the present invention, the heat source to which the thermoelectric power generation module is applied may be a hot heat source or a cold heat source.

[0076] In an embodiment of the present invention, one of the first main surface and the second main surface of the thermoelectric power generation module does not necessarily have to be open. For example, in an embodiment of the present invention, the first main surface of the thermoelectric power generation module may be in contact with one heat source, and the second main surface may be in contact with the other heat source.

[0077] In the embodiment of the present invention, when multiple types of thermoelectric material sections are formed, the absolute values of the electromotive forces of the thermoelectric material sections may be adjusted to be substantially the same. For example, when p-type thermoelectric material sections and n-type thermoelectric material sections are alternately connected in series in a thermoelectric power generation element, the electromotive force of one thermoelectric material section having a higher electromotive force may be weakened to be equal to the electromotive force of the other thermoelectric material section. Such adjustment allows the current generated in the thermoelectric material sections to flow uniformly, further improving the stability of thermoelectric power generation.

[0078] In an embodiment of the present invention, the heat insulating member, the thermoelectric material portion, and the conductive portion may all have sufficient hardness to substantially prevent deformation. For example, the heat insulating member may be a semi-cylindrical organic or inorganic porous body, the thermoelectric material portion may be a rod-shaped member that penetrates the heat insulating member along the thickness direction of the heat insulating member, and the conductive portion may be a conductive film disposed on the ends of the heat insulating member and the thermoelectric material portion. This configuration is advantageous from the viewpoint of facilitating installation on a heat source of a specific shape (e.g., cylindrical) and from the viewpoint of preventing breakage due to deformation.

[0079] In an embodiment of the present invention, a thermoelectric power generation module having a thread-like thermoelectric power generation element and a heat insulating member may be manufactured by a method other than sewing the thread-like thermoelectric power generation element to the heat insulating member. For example, a thermoelectric power generation module of this type can also be manufactured by a method of forming the heat insulating member by supplying a heat insulating material to the thread-like thermoelectric power generation element, which is maintained in a desired shape, in accordance with the shape of the thermoelectric power generation element.

[0080] [summary] As is clear from the above description, the thermoelectric power generation module (1) according to the embodiment of the present invention includes a heat insulating member (10) having a first main surface (11) and a second main surface (12), and a thermoelectric power generation element (20) that is disposed between the first and second main surfaces of the heat insulating member, includes a thermoelectric material portion (21) that generates an electromotive force according to the temperature difference between the first and second main surfaces, and is configured to generate a current in a desired direction. The heat insulating member has a thermal conductivity of 0.2 Wm -1 K -1In the thermoelectric power generation module, thermal insulation between the first and second main surfaces is maintained, and power generation by the thermoelectric power generation elements is possible. Therefore, thermal insulation and power generation efficiency can be achieved at the same time.

[0081] In an embodiment of the present invention, the thermal conductivity between the first main surface and the second main surface is 50 Wm -1 K -1 This configuration is even more effective in terms of sufficiently increasing the thermal insulation of the thermoelectric power generation module.

[0082] In an embodiment of the present invention, the distance from the first main surface to the second main surface of the heat insulating member may be 350 mm or less. This configuration is even more effective in terms of sufficiently increasing the degree of freedom in installing the thermoelectric power generation module on the heat source.

[0083] In an embodiment of the present invention, the shape of the heat insulating member may be flat, with a pair of surfaces that extend at opposing positions when viewed from above the heat insulating member as first main surfaces and a surface that is opposite the first main surfaces in the thickness direction of the heat insulating member as a second main surface, or may be cylindrical, with one of the inner and outer circumferential surfaces as the first main surface and the other as the second main surface. This configuration is even more effective from the viewpoint of sufficiently increasing the degree of freedom and ease of installation of the thermoelectric power generation module on a heat source.

[0084] In an embodiment of the present invention, the thermoelectric material portion may penetrate the heat insulating member between the first principal surface and the second principal surface. This configuration is even more effective in terms of increasing the power generation efficiency of the thermoelectric power generation module.

[0085] In an embodiment of the present invention, the thermoelectric material portion contains a thermoelectric material that generates an electromotive force according to a temperature gradient, and the absolute value of the Seebeck coefficient of the thermoelectric material is 10 μVK. -1 This configuration is even more effective in terms of increasing the power generation efficiency of the thermoelectric power generation module.

[0086] In an embodiment of the present invention, the conductivity of the thermoelectric material is 0.5 Scm -1This configuration is even more effective in terms of increasing the power generation efficiency of the thermoelectric power generation module.

[0087] In the embodiment of the present invention, the thermoelectric material may be a conductive polymer or a carbon material, which is more effective in preventing the thermoelectric material from falling off from the thermoelectric material portion.

[0088] In an embodiment of the present invention, the thermoelectric power generation module may further include a conductive portion electrically connected to the thermoelectric material portion. This configuration is even more effective from the viewpoint of increasing the diversity of electrical configurations of the thermoelectric power generation element.

[0089] In an embodiment of the present invention, the conductive portion contains a conductive material, and the conductive material has a thermal conductivity of 50 Wm -1 K -1 This configuration is even more effective in terms of sufficiently suppressing heat radiation from the conductive portion in the thermoelectric power generation module.

[0090] In an embodiment of the present invention, the Seebeck coefficient of the conductive material is 10 μVK or less if the Seebeck coefficient of the thermoelectric material is positive. -1 or less, and -10 μVK if the sign of the Seebeck coefficient of the thermoelectric material is negative. -1 This configuration is even more effective in terms of realizing a better flow of current in the thermoelectric power generation element and increasing the power generation efficiency of the thermoelectric power generation module.

[0091] In an embodiment of the present invention, the conductive material may be one or more materials selected from the group consisting of metals, conductive polymers, and carbon materials. This configuration is suitable for application to a thermoelectric power generation module with a flexible configuration, and is even more effective in terms of preventing the thermoelectric material from falling off from the thermoelectric material section.

[0092] In an embodiment of the present invention, the thermoelectric power generation element may include a series circuit in which thermoelectric material sections and conductive sections are alternately connected, the thermoelectric material sections independently include a thermoelectric material selected from the group consisting of p-type thermoelectric materials and n-type thermoelectric materials that generate electricity in response to a temperature difference, and the thermoelectric material sections and conductive sections may be arranged alternately in the planar direction of the heat insulating member between the first principal surface and the second principal surface. This configuration is even more effective from the viewpoint of realizing power generation at a sufficiently high voltage with a simple configuration.

[0093] In an embodiment of the present invention, the thermoelectric power generation elements may be in the form of flexible fibers, which is even more effective in preventing damage to the thermoelectric power generation elements due to deformation of the thermoelectric power generation module.

[0094] In an embodiment of the present invention, the thermoelectric power generation element may include insulating fibers, and a power generation material that generates an electromotive force in response to a temperature gradient may be supported on the fibers to form a thermoelectric material portion. This configuration is even more effective from the viewpoint of suppressing damage to the thermoelectric power generation element due to deformation of the thermoelectric power generation module.

[0095] In an embodiment of the present invention, the thermoelectric power generation element may further include a conductive portion electrically connected to the thermoelectric material portion, and the conductive portion may be formed by carrying a conductive material on the fiber. This configuration is even more effective from the viewpoint of suppressing damage to the thermoelectric power generation element due to deformation of the thermoelectric power generation module.

[0096] A method for manufacturing a thermoelectric power generation module according to an embodiment of the present invention includes the steps of intermittently coating or impregnating insulating fibers with a first thermoelectric material to form first conductive portions, intermittently coating or impregnating the fibers with a second thermoelectric material or conductive material to form second conductive portions connecting the first thermoelectric material portions, and -1 K -1The method includes the steps of: stitching a thermal insulating member having the following thermal conductivity with fibers, and arranging the first conductive portions and the second conductive portions on the thermal insulating member so that the first conductive portions and the second conductive portions alternately cross between the first and second main surfaces of the thermal insulating member, the first conductive portions and the second conductive portions being configured to generate current in one direction, the longitudinal direction of the fibers. According to this manufacturing method, a module that generates thermoelectric power in the thickness direction is manufactured by stitching the thermal insulating member with fibers. Therefore, a thermoelectric power generation module that achieves both thermal insulation and power generation efficiency can be manufactured. In addition, this method is effective in preventing damage to the thermoelectric power generation elements due to deformation of the thermoelectric power generation module.

[0097] In an embodiment of the present invention, the thermal conductivity between the first main surface and the second main surface of the thermoelectric power generation module is 50 Wm -1 K -1 This configuration is even more effective from the viewpoint of achieving both heat insulation and power generation efficiency.

[0098] In addition, in an embodiment of the present invention, by placing the thermoelectric power generation module of this embodiment as a heat insulator against a heat source, sufficient insulation is achieved and electrical energy is generated according to the temperature difference between the heat source separated by the insulating material and the outside. This is expected to increase the rate of improvement in energy efficiency and contribute to the achievement of the Sustainable Development Goals (SDGs).

[0099] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Example]

[0100] Example 1 [Fabrication of fibrous thermoelectric generators] A flexible, insulating cotton thread having a diameter of 1.4 mm was prepared.

[0101] Next, the cotton threads were impregnated with an aqueous dispersion of PEDOT:PSS, "Orgacon ICP-1050" ("Orgacon" is a registered trademark of Agfa-Gevaert), spaced 5 cm apart, and then heated at 170°C for 10 minutes to evaporate the water from the cotton threads. In this way, a p-type thermoelectric material part supported on the cotton threads was formed. The Seebeck coefficient and electrical conductivity of the thermoelectric material part were measured, and the Seebeck coefficient of the thermoelectric material part was found to be 10 μVK. -1 The conductivity of the thermoelectric material is 0.5 Scm -1 That was all.

[0102] Next, a 7cm long silver wire (diameter 0.5mm, 99.99%, Nilaco, thermal conductivity 428Wm -1 K -1 ) was fixed to electrically connect adjacent thermoelectric material sections to form a conductive section. The thermal conductivity of the silver wire referred to here is the physical property value of pure silver. 1 cm of one end of the silver wire overlaps one of the adjacent thermoelectric generation sections, and 1 cm of the other end of the silver wire overlaps the other of the adjacent thermoelectric generation sections. The Seebeck coefficient of the conductive section was measured in the same way as for the thermoelectric material section, and the Seebeck coefficient of the conductive section was found to be 1.3 μVK when measured at room temperature using the measurement method described below. -1 It was.

[0103] In this way, a fibrous thermoelectric power generation element 1 was produced in which PEDOT:PSS and silver wire were supported on cotton thread so that the lengths of the thermoelectric material part, conductive part, and overlapping part were 3 cm, 5 cm, and 1 cm, respectively. Thermoelectric power generation element 1 constitutes a series circuit of thermoelectric material parts in which the thermoelectric material parts and conductive parts are alternately connected.

[0104] The methods for measuring the Seebeck coefficient of the thermoelectric material portion or the conductive portion and the conductivity of the thermoelectric material portion in this example are described below.

[0105] <Method for measuring the Seebeck coefficient of the thermoelectric material or conductive part> By heating one end of the relevant part (thermoelectric material part or conductive part) in the thermoelectric power generation element, a temperature difference was applied to both ends of the part, and the Seebeck coefficient of the part was determined by measuring the voltage generated in the part.

[0106] <Method for measuring the conductivity of thermoelectric material> A film of the thermoelectric material portion was formed on a glass substrate, and the conductivity of the material of the thermoelectric material portion was measured from this film, which was taken as the conductivity of the thermoelectric material portion. The sheet resistance of the film was measured by four-point probe measurement, and the film thickness of the film was also measured, and the conductivity of the thermoelectric material portion was calculated from these measurement results.

[0107] [Fabrication of thermoelectric power generation module] A flat insulating material made of glass wool with a thickness of 3 cm (thermal conductivity 0.2 Wm -1 K -1 (see below) was prepared.

[0108] Next, the thermoelectric power generation element 1 was sewn to the heat insulating member so that the thermoelectric material portions and the conductive portions alternately crossed the heat insulating member in the thickness direction thereof, thereby producing the thermoelectric power generation module 1.

[0109] In the thermoelectric power generation module 1, the aforementioned overlapping portions and 1 cm portions of the conductive portions connected thereto are exposed on each of the first and second main surfaces of the thermal insulating member, and the other portions, i.e., 3 cm long thermoelectric material portions and the central 3 cm long portions of each conductive portion, alternately cross the thermal insulating member along its thickness direction. In this way, in the thermoelectric power generation module 1, the thermoelectric material portions and conductive portions are alternately arranged between the first and second main surfaces of the thermal insulating member in the planar direction of the thermal insulating member. The thermal conductivity between the first and second main surfaces of the thermoelectric power generation module 1 is the maximum value of the thermal conductivity of the materials present and penetrating between the first and second main surfaces. Therefore, the thermal conductivity between the first and second main surfaces is the thermal conductivity of the conductive material. Therefore, the thermal conductivity between the first and second main surfaces is 428 Wm -1 K -1 is.

[0110] Example 2 A thermoelectric power generation element 2 was fabricated in the same manner as in Example 1, except that the conductive portion was formed using silver paste instead of silver wire. That is, silver paste ("Dotite D-500" (manufactured by Fujikura Kasei Co., Ltd., "Dotite" is a registered trademark of the company) with a thermal conductivity of 30 Wm when dry was used. -1 K -1 ) was applied to the cotton thread at the location of the silver thread, and the silver paste was dried by heating at 100°C for 30 minutes to form a conductive part. The thermal conductivity of the silver paste mentioned here is a literature value (catalog value). The Seebeck coefficient of the conductive part was 3.7 μVK when measured at room temperature using the above-mentioned measurement method. -1 It was.

[0111] A thermoelectric power generation module 2 was fabricated in the same manner as in Example 1, except that a thermoelectric power generation element 2 was used instead of the thermoelectric power generation element 1. The thermal conductivity between the first and second principal surfaces of the thermoelectric power generation module 2 was 30 Wm -1 K -1 is.

[0112] 〔evaluation〕 [1] Power generation characteristics of thermoelectric power generation modules The thermoelectric power generation modules 1 and 2 were placed on a hot plate, and the power generation characteristics were measured when the rear surface (second main surface) was heated.

[0113] The hot plate temperature was set to 60°C or 100°C. The outside temperature was 25°C. DC voltage and current sources were connected to the conductive parts at both ends of the thermoelectric generation element on the first main surface side, and the current-voltage characteristics and power-voltage characteristics of the thermoelectric generation element were measured.

[0114] Figure 2 shows the current-voltage characteristics between the heat source (60°C) and outside air (25°C) for thermoelectric power generation modules 1 and 2. Figure 3 shows the power-voltage characteristics between the heat source (60°C) and outside air (25°C) for thermoelectric power generation modules 1 and 2. Figure 4 shows the current-voltage characteristics between the heat source (100°C) and outside air (25°C) for thermoelectric power generation modules 1 and 2. Figure 5 shows the power-voltage characteristics between the heat source (100°C) and outside air (25°C) for thermoelectric power generation modules 1 and 2.

[0115] 2 and 4, it can be seen that in both thermoelectric power generation module 1 and thermoelectric power generation module 2, the higher the voltage, the larger the current.

[0116] 2 and 4, it can be seen that thermoelectric power generation module 2 has a larger voltage at zero current and generates a larger thermoelectromotive force than thermoelectric power generation module 1. This is thought to be because the thermal conductivity of the electrode material of thermoelectric power generation module 2 is lower than that of thermoelectric power generation module 1, resulting in a larger temperature difference between the first and second main surfaces of thermoelectric power generation module 2.

[0117] 2 and 4, the absolute value of the current value at zero voltage is larger in thermoelectric power generation module 2 than in thermoelectric power generation module 1. This is thought to be because the contact resistance between the thermoelectric material part and the conductive part is smaller in thermoelectric power generation module 2 than in thermoelectric power generation module 1, and the series resistance of the thermoelectric power generation module is also smaller.

[0118] 3 and 5, it can be seen that both thermoelectric power generation module 1 and thermoelectric power generation module 2 have peak power values. Whether the hot plate temperature is set to 60°C or 100°C, the power value of thermoelectric power generation module 2 is greater than that of thermoelectric power generation module 1. This is thought to be because the thermal conductivity of the conductive part of thermoelectric power generation module 2 is smaller than that of thermoelectric power generation module 1.

[0119] [2] Dependence of thermoelectric power generation module on thermal conductivity of conductive parts The temperature difference (temperature difference between points a and b in Figure 1) that occurs at both ends of the thermoelectric material when a thermoelectric conversion module with the structure shown in Figure 1 is heated from the backside was calculated using the finite element method. The calculation conditions were a temperature of 60°C on the heating surface (second main surface), an outside air temperature of 10°C, and a heat transfer coefficient of 23 Wm from the thermoelectric conversion module to the outside air. -2 K -1 The thermal conductivity and density of the thermoelectric material were set to 0.17 Wm using the values of PEDOT:PSS. -1 K -1 , 1.01gcm -3 Furthermore, the density of the conductive part was set to 10.49 gcm using the value of silver. -3 The thermal conductivity of the conductive part is set to 2 to 428 Wm -1 K -1 Figure 6 shows the calculation results for the temperature difference between both ends of the thermoelectric material part due to the thermal conductivity of the thermoelectric conversion module.

[0120] As shown in Figure 6, it can be seen that the temperature difference in the thermoelectric material part of a thermoelectric conversion module with the structure shown in Figure 1 becomes smaller as the thermal conductivity of the conductive part becomes higher, and becomes larger as the thermal conductivity of the conductive part becomes lower.

[0121] Furthermore, for the thermoelectric conversion module with the structure shown in Figure 1, the Seebeck coefficient of the thermoelectric material part was set to 15 μVK. -1 Using the temperature difference (Fig. 6) calculated by the finite element method, the electromotive force of the thermoelectric power generation module due to the thermal conductivity of the conductive part was calculated from the product of the temperature difference and the Seebeck coefficient. The calculation results of this electromotive force are shown in Fig. 7.

[0122] Since the thermoelectromotive force is proportional to the temperature difference, it can be seen that the thermoelectromotive force, like the temperature difference, increases as the thermal conductivity of the conductive portion decreases.

[0123] [3] Evaluation of the thermal insulation properties of thermoelectric power generation modules The back surfaces of the thermoelectric power generation modules 1 and 2 were heated with a hot plate, and the surface temperatures of the thermoelectric power generation modules 1 and 2 were measured with a thermometer. The surface temperatures were measured at the portions of the thermoelectric power generation elements 1 and 2 that were exposed on the surfaces. For comparison, the surface temperatures of the heat insulating members of the thermoelectric power generation modules 1 and 2 were also measured. Figure 8 shows the temperatures on the first principal surface side when the thermoelectric power generation modules 1 and 2 were heated from the second principal surface side.

[0124] 8 confirms that the temperatures on the first main surface sides of both thermoelectric power generation module 1 and thermoelectric power generation module 2 are sufficiently lower than the temperatures on the second main surface sides. Also, FIG. 8 shows that when the temperature of the hot plate is increased, the temperature of the thermoelectric power generation elements on the first main surface side increases more significantly in thermoelectric power generation module 1 than in thermoelectric power generation module 2. The temperature of the thermoelectric power generation elements on the first main surface side of thermoelectric power generation module 2 was approximately the same as the temperature of the first main surface of the heat insulating member. Therefore, it can be seen that thermoelectric power generation module 2 has higher thermal insulation properties than thermoelectric power generation module 1. [Industrial Applicability]

[0125] The present invention provides a thermoelectric power generation module that not only generates electricity but also has high thermal insulation properties. It is expected to be used in locations where temperature must be maintained, such as in hot and cold water pipes. [Explanation of symbols]

[0126] 1 Thermoelectric power generation module 10. Heat insulating materials 11 First principal surface 12 Second principal surface 20 Thermoelectric power generation element 21 Thermoelectric Materials Department 22 Conductive part 23 Overlapping Section 24 parts

Claims

1. It has a first principal surface and a second principal surface, and －１ K －１ A heat insulating member having the following thermal conductivity: a flexible, fibrous, thread-like thermoelectric power generation element that is disposed between the first main surface and the second main surface of the heat insulating member, includes a thermoelectric material portion that generates an electromotive force according to a temperature difference between the first main surface side and the second main surface side, and is configured to generate a current in a desired direction; a thermoelectric power generation module in which the thermoelectric power generation element includes a first conductive portion formed by intermittently supporting a first thermoelectric material that generates an electromotive force in response to a temperature gradient on insulating fibers, and a second conductive portion formed by intermittently supporting a second thermoelectric material or a conductive material that generates an electromotive force in response to a temperature gradient on the fibers, and connecting the first conductive portions together; and the first conductive portion and the second conductive portion are alternately arranged in the thermal insulation member so as to cross between the first main surface and the second main surface of the thermal insulation member.

2. The thermal conductivity between the first main surface and the second main surface is 50 Wm －１ K －１ The thermoelectric power generation module according to claim 1 , wherein:

3. The thermoelectric power generation module according to claim 1 , wherein the distance from the first main surface to the second main surface of the heat insulating member is 350 mm or less.

4. The thermoelectric power generation module according to any one of claims 1 to 3, wherein the shape of the insulating member is flat, with the first main surface being the surface visible when the insulating member is viewed in a planar view, and the second main surface being the surface opposite the first main surface in the thickness direction of the insulating member, or is cylindrical, with one of the inner and outer surfaces being the first main surface and the other being the second main surface.

5. 5. The thermoelectric power generation module according to claim 1, wherein the thermoelectric material portion penetrates the heat insulating member between the first main surface and the second main surface.

6. the thermoelectric material portion contains a thermoelectric material that generates an electromotive force in response to a temperature gradient; The Seebeck coefficient of the thermoelectric material is 10 μVK －１ or above or -10μVK －１ Below is the The thermoelectric power generation module according to any one of claims 1 to 5.

7. The thermoelectric material has a conductivity of 0.5 Scm －１ The thermoelectric power generation module according to claim 6 .

8. The thermoelectric power generation module according to claim 6 or 7, wherein the thermoelectric material is a conductive polymer or a carbon material.

9. The thermoelectric power generation module according to any one of claims 1 to 8, further comprising a conductive portion electrically connected to the thermoelectric material portion.

10. the conductive portion contains a conductive material, The thermal conductivity of the conductive material is 50 Wm －１ K －１ Below is the The thermoelectric power generation module according to claim 9 .

11. the thermoelectric material portion contains a thermoelectric material that generates an electromotive force in response to a temperature gradient; The Seebeck coefficient of the conductive material is 10 μVK if the sign of the Seebeck coefficient of the thermoelectric material is positive －１ is as follows: -10 μVK if the sign of the Seebeck coefficient of the thermoelectric material is negative －１ That's all. The thermoelectric power generation module according to claim 10 .

12. The thermoelectric power generation module according to claim 10 or 11, wherein the conductive material is one or more materials selected from the group consisting of metals, conductive polymers, and carbon materials.

13. the thermoelectric power generation element includes a series circuit in which the thermoelectric material portions and the conductive portions are alternately connected, the thermoelectric material portion independently includes a thermoelectric material selected from the group consisting of a p-type thermoelectric material and an n-type thermoelectric material that generate electricity in response to a temperature difference; the thermoelectric material portions and the conductive portions are alternately arranged in a plane direction of the heat insulating member between the first principal surface and the second principal surface, The thermoelectric power generation module according to any one of claims 9 to 12.

14. the thermoelectric power generation element includes insulating thread-like fibers, the thermoelectric material portion is formed by carrying a power generating material that generates an electromotive force in response to a temperature gradient on the fibers; The thermoelectric power generation module according to any one of claims 1 to 13.

15. the thermoelectric power generation element further includes a conductive portion electrically connected to the thermoelectric material portion, The conductive portion is formed by carrying a conductive material on the fiber. The thermoelectric power generation module according to claim 14 .

16. 1. A method for manufacturing a thermoelectric power generation module, comprising: a step of intermittently coating or impregnating insulating fibers with a first thermoelectric material to form a first conductive portion; intermittently coating or impregnating the fibers with a second thermoelectric material or conductive material to form second conductive portions connecting the first thermoelectric material portions; 0.2Wm －１ K －１ a step of stitching an insulating member having the following thermal conductivity with the fibers, and arranging the first conductive portion and the second conductive portion in the insulating member so that the first conductive portion and the second conductive portion alternately cross between the first main surface and the second main surface of the insulating member; Including, A method for manufacturing a thermoelectric power generation module, wherein the first conductive portion and the second conductive portion are configured to generate an electric current in one direction, the length direction of the fiber.

17. The thermal conductivity between the first main surface and the second main surface of the thermoelectric power generation module is 50 Wm －１ K －１ The method for manufacturing a thermoelectric power generation module according to claim 16, wherein:

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