Thermoelectric battery, method for manufacturing thermoelectric battery, and method for manufacturing thermoelectric generator

Abstract

To provide a thermal power generation battery practical under high temperature environment, and to provide a manufacturing method of thermal power generation battery and a manufacturing method of thermal power generator.SOLUTION: A thermal power generation battery comprises a thermal power generator including multiple heat utilization power generation elements laminating a thermoelectric conversion layer and a solid electrolyte layer, and converting thermal energy into electrical energy, a conductive case including a first case body and a second case body combined in insulation state, and receiving the thermal power generator, an insulation member for electrically insulating the first case body or the second case body and the solid electrolyte layer on the lateral face of the thermal power generator, while electrically insulating the first and second case bodies, and a compression conductor received in the case, and sandwiched by the thermal power generator and the case and compressed. By placing the compression conductor on at least one side of the first and second case bodies, the first case body, the thermal power generator and the second case body are electrically connected in the lamination direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a thermoelectric battery, a method for manufacturing a thermoelectric battery, and a method for manufacturing a thermoelectric generator, and more particularly to a thermoelectric battery that exhibits a thermoelectric conversion function, a method for manufacturing a thermoelectric battery, and a method for manufacturing a thermoelectric generator. [Background technology]

[0002] As a method of thermal power generation using geothermal heat or exhaust heat from a factory, a method using the Seebeck effect can be mentioned. As a thermal power generation method not using the Seebeck effect, a thermal power generation element disclosed in the following Patent Document 1 can be mentioned. The following Patent Document 1 discloses that thermal energy is converted into electrical energy by combining an electrolyte with a thermoelectric conversion material that generates thermally excited electrons and holes. By using such a thermal power generation element as a power source for electronic components, stable power can be supplied to the electronic components, for example, even in a high-temperature environment (e.g., 50°C or higher) where general batteries are prone to deterioration. For this reason, research and development is being conducted to put the above-mentioned thermal power generation element into practical use. One of the themes of research and development is a practical package structure of the above-mentioned thermal power generation element from the viewpoint of ensuring ease of replacement with conventional batteries. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 038988 [Patent Document 2] JP 2010-56067 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, one type of battery is the coin battery. This coin battery requires a power source independent of an external power source and is mainly used for electronic components with low power consumption. The above-mentioned Patent Document 2 discloses a coin-type lithium secondary battery that contains a spring as a measure against variations in contact surface pressure caused by expansion or the like that accompanies use.

[0005] In order to obtain a battery that can be used in a high-temperature environment, it is conceivable to combine, for example, a coin-type battery as described in Patent Document 2 with the heat-utilizing power generation element as described in Patent Document 1. However, simply implementing the above combination does not result in a battery that can withstand practical use in terms of electromotive force, reliability, etc. Therefore, further improvements are necessary.

[0006] An object of one aspect of the present invention is to provide a thermoelectric battery that can be used in high-temperature environments, a method for manufacturing a thermoelectric battery, and a method for manufacturing a thermoelectric generator. [Means for solving the problem]

[0007] A thermoelectric battery according to one aspect of the present invention includes a thermoelectric generator that includes a plurality of heat-utilizing power generation elements in which a thermoelectric conversion layer and a solid electrolyte layer are stacked, and that converts thermal energy into electrical energy; a first case body and a second case body that are combined in an insulated state; a conductive case that houses the thermoelectric generator; an insulating member that electrically insulates the first case body and the second case body while electrically insulating the first case body or the second case body from the solid electrolyte layer on a side of the thermoelectric generator; and a compressed conductor that is housed in the case and compressed while sandwiched between the thermoelectric generator and the case; and by arranging the compressed conductor on at least one side of the first case body and the second case body, the first case body, the thermoelectric generator, and the second case body are electrically connected in the stacking direction of the thermoelectric conversion layer and the solid electrolyte layer.

[0008] The thermoelectric battery includes a thermoelectric generator that generates electricity by application of heat. The thermoelectric generator has a plurality of heat-utilizing power generation elements stacked in a stacking direction. This can improve the electromotive force of the thermoelectric battery. A compressed conductor is also housed in the case that houses the thermoelectric generator. This can prevent unnecessary pressure from being applied to the thermoelectric generator, thereby suppressing damage to the thermoelectric generator. Furthermore, since the compressed conductor is interposed between the case and the thermoelectric generator, poor contact between the case and the thermoelectric generator can be effectively prevented. Therefore, according to the above aspect, a thermoelectric battery that can be used in high-temperature environments can be provided.

[0009] The thermoelectric conversion layer has an electron thermal excitation layer and an electron transport layer stacked in this order, and the electron thermal excitation layer may be in contact with the solid electrolyte layer. In this case, electrons are efficiently extracted from the electron thermal excitation layer via the electron transport layer, thereby improving the performance of the thermoelectric generator.

[0010] The compressed conductor may be a porous metal body. In this case, the compressed conductor easily undergoes plastic deformation, thereby reducing the pressure applied to the thermoelectric generator from the case via the compressed conductor, thereby suppressing damage to the thermoelectric generator.

[0011] In the thermoelectric battery, the compressed conductor may be disposed on both sides of the first case body and the second case body, which makes it possible to more effectively prevent poor contact between the thermoelectric generator and the first and second case bodies.

[0012] Each of the first case body and the second case body may have a cylindrical shape with one end closed and the other end open.

[0013] A manufacturing method for a thermoelectric battery according to another aspect of the present invention includes the steps of forming a heat-utilizing power generation element by repeatedly stacking thermoelectric conversion layers and solid electrolyte layers to obtain a thermoelectric generator, housing the thermoelectric generator and a compressed conductor in either a first case body or a second case body having electrical conductivity, and housing the thermoelectric generator in a case by combining the first case body and the second case body with an insulating member interposed therebetween so that the first case body or the second case body housing the thermoelectric generator is electrically insulated from the side of the thermoelectric generator and the first case body is electrically insulated from the second case body.

[0014] The above manufacturing method provides a method for manufacturing a thermoelectric battery that can be used in a high-temperature environment.

[0015] A method for producing a thermoelectric generator according to yet another aspect of the present invention is a method for producing a thermoelectric generator including a plurality of heat-utilizing power generation elements in which a thermoelectric conversion layer and a solid electrolyte layer are stacked, and includes a step of forming a thermoelectric conversion layer and then repeating a step of forming a solid electrolyte on the thermoelectric conversion layer multiple times to obtain a thermoelectric generator. This production method can provide a method for producing a thermoelectric generator that can be used in practical applications. Effect of the Invention

[0016] According to one aspect of the present invention, it is possible to provide a thermoelectric battery that can be used in high-temperature environments, a method for manufacturing a thermoelectric battery, and a method for manufacturing a thermoelectric generator. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a thermoelectric power generating battery according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram for explaining the power generation mechanism of the thermal power generation element. [Diagram 3] 3(a) to (c) are diagrams illustrating a method for manufacturing a thermoelectric generator. [Figure 4] FIG. 4 is a diagram for explaining a method for manufacturing a thermoelectric battery. [Diagram 5]FIG. 5(a) is a schematic cross-sectional view showing a thermoelectric power generating battery according to a first modified example of the embodiment, and FIG. 5(b) is a schematic cross-sectional view showing a thermoelectric power generating battery according to a second modified example of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same elements or elements having the same functions will be denoted by the same reference numerals, and duplicated description will be omitted.

[0019] First, the configuration of the coin battery according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view showing a thermoelectric battery according to this embodiment. The thermoelectric battery 1 shown in Fig. 1 is a heat-utilizing battery that generates power by receiving heat from the outside. The thermoelectric battery 1 has a case 2, a thermoelectric generator 3, a compressed conductor 4, and a gasket 5. The gasket 5 corresponds to an example of an insulating member.

[0020] The case 2 is a hollow container made of a conductive metal or alloy, and has a housing 11 and a lid 12. In this embodiment, the case 2 is made of stainless steel. Either the housing 11 or the lid 12 corresponds to one example of either the first case body or the second case body, and the other of the housing 11 and the lid 12 corresponds to one example of the other of the first case body or the second case body.

[0021] The housing 11 is a member that functions as one of the positive and negative electrodes of the thermoelectric battery 1, and houses the thermoelectric generator 3, the compressed conductor 4, and the gasket 5. The housing 11 has a bottom plate 11a and a side wall 11b. The bottom plate 11a has, for example, a circular plate shape, an elliptical plate shape, a polygonal plate shape, or the like. The side wall 11b is provided along the edge of the bottom plate 11a. In this embodiment, since the bottom plate 11a has a circular plate shape, the housing 11 has a bottomed cylindrical shape with one end closed by the bottom plate 11a and the other end open.

[0022] The lid 12 is a member that functions as the other of the positive and negative electrodes in the thermoelectric generating battery 1, and seals the housing 11 via a gasket 5. The lid 12 has a top plate 12a and a side wall 12b. The top plate 12a has, for example, a disk shape, an elliptical plate shape, a polygonal plate shape, or the like. The diameter of the top plate 12a is smaller than the inner diameter of the housing 11. Therefore, when the housing 11 and the lid 12 are combined, the lid 12 is disposed so as to be surrounded by the side wall 11b of the housing 11. In addition, the side wall 12b is provided along the edge of the top plate 12a and extends toward the bottom plate 11a. In this embodiment, since the top plate 12a also has a disk shape, the lid 12 has a bottomed cylindrical shape with one end closed by the top plate 12a and the other end open.

[0023] The thermoelectric generator 3 is a component that generates electricity when heat is supplied from the outside (i.e., a component that converts thermal energy into electrical energy), and is electrically connected to the housing 11 and the lid 12 of the case 2. In this embodiment, the thermoelectric generator 3 is in contact with the bottom plate 11a of the housing 11, while being separated from the side wall 11b of the housing 11 and the lid 12. The presence of the gasket 5 between the thermoelectric generator 3 and the side walls 11b, 12b makes it possible to prevent a short circuit in the thermoelectric battery 1. Furthermore, when the thermoelectric generator 3 is housed in the case 2, the thermoelectric generator 3 is arranged so as to be surrounded by the side wall 12b of the lid 12.

[0024] The thermoelectric generator 3 has a plurality of thermal power generation elements 21 stacked. For example, the thermoelectric generator 3 has 1 to 10 thermal power generation elements 21. Each thermal power generation element 21 generates thermally excited electrons and holes when heat is supplied from the outside. The generation of thermally excited electrons and holes by the thermal power generation element 21 is performed, for example, at a temperature of 25°C to 300°C. From the viewpoint of generating a sufficient number of thermally excited electrons and holes, the thermal power generation element 21 may be heated to 50°C or higher when the thermoelectric power generation battery 1 is in use. From the viewpoint of effectively preventing deterioration of the thermal power generation element 21, the thermal power generation element 21 may be heated to 200°C or lower when the thermoelectric power generation battery 1 is in use. The temperature at which a sufficient number of thermally excited electrons are generated is, for example, a temperature at which "the thermally excited electron density of the thermal power generation element 21 is 10 15 / cm 3 "The temperature at which the temperature is equal to or higher than this."

[0025] The multiple heat-utilization power generating elements 21 are stacked along the direction in which the housing 11 and the lid 12 of the case 2 are assembled (hereinafter simply referred to as the "stacking direction"). Therefore, each of the multiple heat-utilization power generating elements 21 is connected in series. Each of the multiple heat-utilization power generating elements 21 has a thermoelectric conversion layer 22 and a solid electrolyte layer 23 stacked in the stacking direction. Therefore, the thermoelectric conversion layers 22 and the solid electrolyte layers 23 are alternately stacked to form a thermoelectric generator 3 in which the thermoelectric conversion layers 22 and the solid electrolyte layers 23 are repeatedly stacked. The thermoelectric conversion layer 22 has an electron thermal excitation layer 22a and an electron transport layer 22b stacked in the stacking direction.

[0026] The electronic thermal excitation layer 22a is a layer that generates thermally excited electrons and holes in the heat-utilizing power generating element 21, and is in contact with the solid electrolyte layer 23. The electronic thermal excitation layer 22a includes a thermoelectric conversion material. The thermoelectric conversion material is a material in which excited electrons increase in a high-temperature environment, and is, for example, a semiconductor material such as a metal semiconductor (Si, Ge), a tellurium compound semiconductor, a silicon germanium (Si-Ge) compound semiconductor, a silicide compound semiconductor, a skutterudite compound semiconductor, a clathrate compound semiconductor, a Heusler compound semiconductor, a half-Heusler compound semiconductor, a metal oxide semiconductor, or an organic semiconductor. From the viewpoint of generating sufficient thermally excited electrons at a relatively low temperature, the thermoelectric conversion material may be germanium (Ge). The electronic thermal excitation layer 22a may include a plurality of thermoelectric conversion materials. The electronic thermal excitation layer 22a may include a material other than the thermoelectric conversion material. For example, the electronic thermal excitation layer 22a may include a binder that binds the thermoelectric conversion material, a sintering aid that assists in forming the thermoelectric conversion material, and the like. The electron thermal excitation layer 22a is formed by, for example, a squeegee method, a screen printing method, a discharge plasma sintering method, a compression molding method, a sputtering method, a vacuum deposition method, a chemical vapor deposition method (CVD method), a spin coating method, or the like.

[0027] The electron transport layer 22b is a layer that transports thermally excited electrons generated in the electron thermal excitation layer 22a to the outside, and is located on the opposite side of the solid electrolyte layer 23 via the electron thermal excitation layer 22a in the stacking direction. Therefore, in this embodiment, the electron transport layer 22b, which is closest to the bottom plate 11a of the housing 11 in the thermoelectric generator 3, contacts the bottom plate 11a. The electron transport layer 22b includes an electron transport material. The electron transport material is a material whose conductive charge potential is the same as or more positive than the conductive charge potential of the thermoelectric conversion material. The difference between the conductive charge potential of the electron transport material and the conductive charge potential of the thermoelectric conversion material is, for example, 0.01 V or more and 0.1 V or less. The electron transport material is, for example, a semiconductor material, a metal material, an electron transporting organic material, or the like. The electron transport layer 22b is formed by, for example, a squeegee method, a screen printing method, a discharge plasma sintering method, a compression molding method, a sputtering method, a vacuum deposition method, a CVD method, a spin coating method, or the like.

[0028] The semiconductor material is, for example, the same as the semiconductor material contained in the electron thermal excitation layer 22a. The metal material is, for example, a metal, an alloy, an N-type metal oxide, an N-type metal sulfide, an alkali metal halide, an alkali metal, or the like. The N-type metal is, for example, niobium, titanium, zinc, tin, vanadium, indium, tungsten, tantalum, zirconium, molybdenum, and manganese. The electron transporting organic material is, for example, an N-type conductive polymer, an N-type low molecular weight organic semiconductor, a π-electron conjugated compound, or the like. The electron transport layer 22b may contain a plurality of electron transport materials. The electron transport layer 22b may contain a material other than the electron transport material. For example, the electron transport layer 22b may contain a binder that binds the electron transport material, a sintering aid that assists in forming the electron transport material, and the like.

[0029] The electron transport layer 22b may have a single-layer structure or a multi-layer structure. For example, the electron transport layer 22b may be a laminate of a metal layer and a semiconductor layer. In this case, the semiconductor layer may be in contact with the electron thermal excitation layer 22a. From the viewpoint of preventing or suppressing a chemical reaction of the metal layer, the metal contained in the metal layer is, for example, titanium, gold, platinum, silver, tungsten, tantalum, or the like. In one example, the metal layer is a platinum layer (Pt layer), and the semiconductor layer is an n-type Si layer. The n-type Si layer is formed, for example, by doping a silicon layer with phosphorus or the like.

[0030] The solid electrolyte layer 23 is a layer containing a solid electrolyte in which charge transport ion pairs can move inside at a temperature at which a sufficient number of thermally excited electrons are generated in the thermoelectric generator 3. The charge transport ion pairs move inside the solid electrolyte layer 23, causing a current to flow through the solid electrolyte layer 23. The "charge transport ion pair" is a stable pair of ions with different valences. When one ion is oxidized or reduced, it becomes the other ion and can move electrons and holes. The redox potential of the charge transport ion pair in the solid electrolyte layer 23 is more negative than the valence potential of the thermoelectric conversion material contained in the electronic thermal excitation layer 22a. Therefore, at the interface between the electronic thermal excitation layer 22a and the solid electrolyte layer 23, the ion that is easily oxidized among the charge transport ion pairs is oxidized and becomes the other ion. The solid electrolyte layer 23 may contain ions other than the charge transport ion pair. The solid electrolyte layer 23 can be formed by, for example, a squeegee method, a screen printing method, a sputtering method, a vacuum deposition method, a CVD method, a sol-gel method, or a spin coating method.

[0031] The solid electrolyte contained in the solid electrolyte layer 23 is, for example, a material that is physically and chemically stable at the above temperature and contains polyvalent ions. The solid electrolyte is, for example, a sodium ion conductor, a copper ion conductor, an iron ion conductor, a lithium ion conductor, a silver ion conductor, a hydrogen ion conductor, a strontium ion conductor, an aluminum ion conductor, a fluorine ion conductor, a chloride ion conductor, an oxide ion conductor, or the like. The solid electrolyte may be, for example, polyethylene glycol (PEG) having a molecular weight of 600,000 or less or a derivative thereof. When the solid electrolyte is PEG, a polyvalent ion source such as copper ions or iron ions may be contained in the solid electrolyte layer 23. From the viewpoint of improving the life, etc., an alkali metal ion may be contained in the solid electrolyte layer 23. The molecular weight of PEG corresponds to a weight average molecular weight measured in terms of polystyrene by gel permeation chromatography. The solid electrolyte layer 23 may contain a material other than the solid electrolyte. For example, the solid electrolyte layer 23 may contain a binder that binds the solid electrolyte, a sintering aid that assists in forming the solid electrolyte, and the like.

[0032] Here, an overview of the power generation mechanism of the thermal power generation element will be described with reference to FIG. 2. FIG. 2 is a schematic diagram for explaining the power generation mechanism of the thermal power generation element. For the purpose of explanation, the charge transport ion pair contained in the solid electrolyte layer 23 in this paragraph will be assumed to be iron ions (Fe 2+ ,Fe 3+ First, in a high-temperature environment, electrons e excited in the electron thermal excitation layer 22a are - This electron e - The electrons move to the electron transport layer 22b. As a result, the electron thermal excitation layer 22a is filled with holes h + This hole h + At the first interface between the electron thermal excitation layer 22a and the solid electrolyte layer 23, Fe 2+ That is, this hole h + At the first interface, Fe 2+ This causes the Fe 2+ Fe 3+ On the other hand, the excess electrons e -The electrons e move to the outside, pass through the resistor R and the terminal T, and reach the solid electrolyte layer 23. The electrons e - At the second interface between the solid electrolyte layer 23 and the terminal T, 3+ This reduces the Fe at the second interface. 3+ Fe 2+ Then, the oxidized Fe at the first interface 3+ is diffused toward the second interface, and reduced Fe at the second interface is 2+ is diffused toward the first interface. This maintains the oxidation-reduction reaction between the first interface and the second interface. The thermal energy generating element 21 generates electricity by generating electrons through such thermal excitation and the oxidation-reduction reaction. Note that the work generated when the electrons pass through the resistor R corresponds to power generation.

[0033] Returning to FIG. 1, the compressed conductor 4 is a member that fills the gap between the case 2 and the thermoelectric generator 3 in the stacking direction, and is sandwiched between the case 2 and the thermoelectric generator 3 in the stacking direction. In this embodiment, the compressed conductor 4 is located between the thermoelectric generator 3 and the lid 12 in the stacking direction, and is in contact with the solid electrolyte layer 23 of the thermoelectric generator 3 and the top plate 12a of the lid 12. The compressed conductor 4 is, for example, a porous metal body. Therefore, when the thermoelectric generator 3 and the compressed conductor 4 are sealed in the case 2, the compressed conductor 4 can be compressed and deformed. The porous metal body is a three-dimensional porous metal body in which a plurality of holes are provided, and the holes in the porous metal body may be connected to each other or may be separated from each other. The porous metal body may be formed in a mesh shape when viewed from the stacking direction. In this case, each mesh when viewed from the stacking direction has a polygonal shape, such as a rhombus shape or a hexagon shape. The porous metal body may be, for example, a processed product of an expanded metal.

[0034] From the viewpoint of reducing the pressure applied to the thermoelectric generator 3, the compressed conductor 4 may have a significantly smaller elastic force than a metal spring or the like. In other words, from the above viewpoint, the compressed conductor 4 may be a member that undergoes plastic deformation. From the viewpoint of reducing the pressure applied to the thermoelectric generator 3 when the thermoelectric cell 1 is heated, the compressed conductor 4 may be formed from an indeformable steel plate. In this case, the compressed conductor 4 is less susceptible to thermal expansion, so that the pressure applied from the compressed conductor 4 to the thermoelectric generator 3 can be effectively reduced.

[0035] The gasket 5 is an insulating member that fills gaps within the case 2. In this embodiment, the gasket 5 fills the gap between the side wall 11b of the housing 11 and the side surface of the thermoelectric generator 3. The gasket 5 also covers the periphery of the side wall 12b of the lid 12. This allows the gasket 5 to effectively prevent a short circuit between the housing 11 and the lid 12. The gasket 5 contains a resin material that exhibits heat resistance and insulating properties, such as a fluorine-containing resin.

[0036] Next, an example of a method for manufacturing the thermoelectric battery 1 according to this embodiment will be described with reference to Figures 3(a) to (c) and Figure 4. Figures 3(a) to (c) are diagrams for explaining the method for manufacturing a thermoelectric generator, and Figure 4 is a diagram for explaining the method for manufacturing a thermoelectric battery.

[0037] First, as shown in Figures 3(a) and (b), an electron thermal excitation layer 22a is formed on an electron transport layer 22b to form a thermoelectric conversion layer 22. In this embodiment, as shown in Figure 3(a), a semiconductor material target 41 constituting the electron thermal excitation layer 22a is sputtered to form the electron thermal excitation layer 22a on the electron transport layer 22b. The electron transport layer 22b is formed in advance on a temporary substrate or the like by, for example, a method described later.

[0038] Next, as shown in Figures 3(b) and (c), a solid electrolyte layer 23 is formed on the thermoelectric conversion layer 22 to form the heat-utilizing power generating element 21. In this embodiment, as shown in Figure 3(b), a material constituting the solid electrolyte layer 23 is supplied from a shower head 51 by a CVD method and laminated on the thermoelectric conversion layer 22 to form the solid electrolyte layer 23. In this way, the heat-utilizing power generating element 21 is formed as shown in Figure 3(c).

[0039] Next, an electron transport material target 42 constituting the electron transport layer 22b is sputtered to form the electron transport layer 22b on the thermal power generating element 21. In this manner, the formation of each layer shown in Figures 3(a) to (c) is repeated multiple times to form a thermoelectric generator 3 having a plurality of thermal power generating elements 21.

[0040] 4, the thermoelectric generator 3 and the compressed conductor 4 are prepared. Subsequently, the thermoelectric generator 3 and the compressed conductor 4 are housed in the housing 11. At this time, the thermoelectric generator 3 is placed on the bottom plate 11a of the housing 11, and then the compressed conductor 4 is placed on the thermoelectric generator 3. In addition, a gasket 5 is provided so that the side wall 11b of the housing 11 and the side surface of the thermoelectric generator 3 are electrically insulated.

[0041] Next, the housing 11 and the lid 12 are combined with the gasket 5 interposed therebetween to seal the thermoelectric generator 3 and the compressed conductor 4. At this time, the side wall 12b of the lid 12 is embedded in the gasket 5. This ensures an insulating state between the side wall 12b of the lid 12 and the side wall 11b of the housing 11, the side surface of the thermoelectric generator 3, and the side surface of the compressed conductor 4. In other words, the side wall 12b of the lid 12 is electrically insulated from the side wall 11b of the housing 11, the side surface of the thermoelectric generator 3, and the side surface of the compressed conductor 4. Then, the housing 11 and the lid 12 are crimped together to manufacture the thermoelectric battery 1 shown in FIG. 1.

[0042] The thermoelectric battery 1 manufactured by the manufacturing method according to the present embodiment described above includes a thermoelectric generator 3 that generates electricity by application of heat. The thermoelectric generator 3 has a plurality of thermoelectric power generation elements 21 stacked in the stacking direction. This can improve the electromotive force of the thermoelectric battery 1, so that the thermoelectric battery 1 can function well as a power source for electronic components. Furthermore, each of the thermoelectric power generation elements 21 has a thermoelectric conversion layer 22 and a solid electrolyte layer 23. This allows the thermoelectric battery 1 installed in a high-temperature environment to supply electrical energy to connected electronic components for a long period of time by converting heat into electricity. Furthermore, it is possible to omit current collectors between the plurality of thermoelectric power generation elements 21, which are required in normal batteries.

[0043] The case 2 that houses the thermoelectric generator 3 also houses a compressed conductor 4. This compressed conductor 4 fills the gap between the case 2 and the thermoelectric generator 3, thereby effectively preventing poor contact between the case 2 and the thermoelectric generator 3. In addition, the thermoelectric generator 3 is less likely to expand with use and to undergo thermal expansion compared to lithium secondary batteries and the like. Therefore, the contact surface pressure between the thermoelectric generator 3 and the case 2 (the housing 11 and the lid 12) is less likely to change compared to lithium secondary batteries and the like. Therefore, even if the compressed conductor 4 is used instead of the spring as shown in the above Patent Document 1, for example, a decrease in current density is sufficiently suppressed. In addition, since it is possible to prevent unnecessary pressure from being applied to the thermoelectric generator 3, damage to the thermoelectric generator 3 can be suppressed. Therefore, according to this embodiment, a thermoelectric battery 1 that can be used in high-temperature environments can be provided.

[0044] In addition, the thermoelectric power generating battery 1 according to this embodiment can be made smaller and thinner, which makes it possible to use the thermoelectric power generating battery 1 as a power source for electronic components such as sensors that are placed in high-temperature environments.

[0045] In this embodiment, the thermoelectric conversion layer 22 has an electron thermal excitation layer 22a and an electron transport layer 22b which are laminated in this order, and the electron thermal excitation layer 22a is in contact with the solid electrolyte layer 23. Therefore, electrons can be efficiently extracted from the electron thermal excitation layer 22a, improving the performance of the thermoelectric generator 3. In addition, even if no current collector is provided between the thermal power generation elements 21, the thermoelectric generator 3 can exhibit good performance.

[0046] In this embodiment, the compressed conductor 4 may be a porous metal body. In this case, the elasticity of the compressed conductor 4 can be reduced, and the pressure applied to the thermoelectric generator 3 from the case 2 via the compressed conductor 4 can be reduced. As a result, damage to the thermoelectric generator 3 can be effectively suppressed.

[0047] Below, modifications of the above embodiment will be described with reference to Figures 5(a) and (b). In the following description of each modification, descriptions that overlap with the above embodiment will be omitted. Therefore, below, only the parts that differ from the above embodiment will be described. Figure 5(a) is a schematic cross-sectional view showing a thermoelectric power generating battery according to a first modification of the embodiment, and Figure 5(b) is a schematic cross-sectional view showing a thermoelectric power generating battery according to a second modification of the embodiment.

[0048] The thermoelectric battery 1A shown in FIG. 5(a) includes a compressed conductor 4A instead of the compressed conductor 4. The compressed conductor 4A is located between the bottom plate 11a of the housing 11 and the thermoelectric generator 3 in the stacking direction. Therefore, the compressed conductor 4A contacts the bottom plate 11a and the electron transport layer 22b of the thermoelectric generator 3. On the other hand, in the first modified example, the top plate 12a of the lid 12 directly contacts the solid electrolyte layer 23. In this first modified example as well, the same effects as those of the above embodiment can be achieved.

[0049] The thermoelectric battery 1B shown in Fig. 5(b) includes both compressed conductors 4 and 4A. In this second modified example, the same effects as those of the above embodiment can be achieved. In addition, poor contact between the case 2 and the thermoelectric generator 3 can be more effectively prevented.

[0050] The thermoelectric battery, the manufacturing method of the thermoelectric battery, and the manufacturing method of the thermoelectric generator according to the present invention are not limited to the above-mentioned embodiment and the above-mentioned modification, and various other modifications are possible. For example, in the above-mentioned embodiment and the above-mentioned modification, the thermoelectric conversion layer includes an electron transport layer, but this is not limited thereto. In other words, the thermoelectric conversion layer does not have to include an electron transport layer. [Explanation of symbols]

[0051] 1, 1A, 1B...thermoelectric battery, 2...case, 3...thermoelectric generator, 4, 4A...compressed conductor, 5...gasket, 11...housing, 11a...bottom plate, 11b...side wall, 12...lid, 12a...top plate, 12b...side wall, 21...thermoelectric power generation element, 22...thermoelectric conversion layer, 22a...electron thermal excitation layer, 22b...electron transport layer, 23...solid electrolyte layer.

Claims

1. a thermoelectric generator including a plurality of heat utilization power generation elements each having a thermoelectric conversion layer and a solid electrolyte layer stacked thereon, the thermoelectric generator converting thermal energy into electrical energy; a conductive case including a first case body and a second case body that are combined with each other and that houses the thermoelectric generator; an insulating member that electrically insulates the first case body and the second case body and electrically insulates the first case body or the second case body from the solid electrolyte layer on a side surface of the thermoelectric generator; a compressed conductor housed in the case and positioned between the thermoelectric generator and the case; Equipped with by arranging the compressed conductor on at least one side of the first case body and the second case body, the first case body, the thermoelectric generator, and the second case body are electrically connected in a stacking direction of the thermoelectric conversion layer and the solid electrolyte layer, The compressed conductor is in contact with the thermoelectric conversion layer.

2. The thermoelectric battery according to claim 1 , wherein the compressed conductor is sandwiched between the thermoelectric generator and the case so as to fill a gap between the thermoelectric generator and the case.

3. a conductive case including a first case body and a second case body; a heat-utilizing power generating element that is housed in the conductive case and includes a thermoelectric conversion layer and a solid electrolyte layer that are laminated in this order; an insulating member that electrically insulates the first case body from the second case body and electrically insulates the first case body or the second case body from the solid electrolyte layer on a side surface of the heat-utilizing power generating element; a compressed conductor housed in the case and positioned between the heat-utilizing power generating element and the case; Equipped with the first case body, the heat utilization power generation element, and the second case body are electrically connected to each other; The compressed conductor is in contact with the thermoelectric conversion layer.

4. 4. The thermoelectric battery according to claim 1, wherein the compressed conductor is sandwiched between the thermoelectric generating element and the case so as to fill a gap between the thermoelectric generating element and the case.

5. The thermoelectric conversion layer has an electron thermal excitation layer and an electron transport layer stacked on each other, The thermoelectric battery according to any one of claims 1 to 4, wherein the electronic thermal excitation layer is in contact with the solid electrolyte layer.

6. The thermoelectric battery of claim 5 , wherein the compressed electrical conductor contacts the electron transport layer.

7. The thermoelectric battery according to any one of claims 1 to 6, wherein the compressed conductor is a porous metal body.

8. The thermoelectric battery according to any one of claims 1 to 7, wherein the compressed conductor is disposed on both sides of the first case body and the second case body.

9. The thermoelectric battery according to any one of claims 1 to 8, wherein each of the first case body and the second case body has a bottomed cylindrical shape with one end closed and the other end open.

10. the first case body has a first plate member and a first side wall provided along an edge of the first plate member, The thermoelectric battery according to any one of claims 1 to 9, wherein the second case body has a second plate member and a second side wall provided along an edge of the second plate member.

11. The thermoelectric battery of any one of claims 1 to 10, wherein the compressed electrical conductor is formed from unaltered steel sheet.

12. forming a plurality of thermal power generation elements each having a thermoelectric conversion layer and a solid electrolyte layer stacked thereon to obtain a thermoelectric generator; housing the thermoelectric generator and the compressed conductor in either a first case body or a second case body having electrical conductivity; a step of combining the first case body and the second case body with an insulating member interposed therebetween so that the first case body or the second case body housing the thermoelectric generator is electrically insulated from a side surface of the thermoelectric generator and so that the first case body and the second case body are electrically insulated from each other; Including, The compressed conductor is in contact with the thermoelectric conversion layer.

13. The thermoelectric conversion layer has an electron thermal excitation layer and an electron transport layer stacked on each other, The method for producing a thermoelectric battery according to claim 12 , wherein the electronic thermal excitation layer is in contact with the solid electrolyte layer.

14. The method of claim 13 , wherein the compressed electrical conductor contacts the electron transport layer.

15. the first case body has a first plate member and a first side wall provided along an edge of the first plate member, The method for manufacturing a thermoelectric battery described in any one of claims 12 to 14, wherein the second case body has a second plate member and a second side wall provided along an edge of the second plate member.

16. The thermoelectric generator is housed in a conductive case including the first case body and the second case body, The method for manufacturing a thermoelectric battery according to any one of claims 12 to 15, wherein the compressed conductor is sandwiched between the thermoelectric generator and the case so as to fill a gap between the thermoelectric generator and the case.

17. The method for producing a thermoelectric battery according to any one of claims 12 to 16, wherein the compressed conductor is formed from unaltered steel sheet.

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