WO2016067171A1

WO2016067171A1 - Thermoelectric module

Info

Publication number: WO2016067171A1
Application number: PCT/IB2015/058180
Authority: WO
Inventors: Hitoshi Yoshimi
Original assignee: Aisin Takaoka Co., Ltd.
Priority date: 2014-10-29
Filing date: 2015-10-23
Publication date: 2016-05-06
Also published as: JP6278879B2; JP2016092017A

Abstract

A thermoelectric module having a small heat resistance and excellent heat dissipation, thereby causing a large temperature difference between hot and cold sides, is desired. The thermoelectric module comprises a first thermoelectric element(s) having one of P and N type thermoelectric characteristics; a second thermoelectric element(s) having another of P and N type thermoelectric characteristics; and a first electrode(s) configured to electrically connect between cold sides of the first and second thermoelectric elements, the first electrode(s) having an arch shape extending from the first and second thermoelectric elements so as to function as a heat sink.

Description

THERMOELECTRIC MODULE

(CROSS-REFERENCE TO RELATED APPLICATIONS)
The present application claims priority based on JP Patent Application No.2014-220387, filed in Japan on October 29, 2014, whose entire disclosure is incorporated herein by reference thereto.
The present disclosure relates to a thermoelectric module.

Background

Recently, the technique of direct thermoelectric conversion based on Seebeck Effect is attracting attention, as one of techniques recovering unused waste heat.

A thermoelectric module using thermoelectric element of a bulk type generally has a PI type structure. In such thermoelectric module, P and N type thermoelectric elements are electrically connected in series via a planar electrode, and thermally configured in parallel. In this type of thermoelectric module, a heat flux flowing from a hot side to a cold side causes carriers to be diffused. Thereby, current flowing in a constant direction is generated to enable taking out of electric power.

A producing method of the thermoelectric module as hereinabove mentioned generally includes the processes as follows:
cutting off P and N type thermoelectric elements from ingots made of P and N type thermoelectric materials produced by a hot pressing technology etc., respectively;
Placing the cut-off P and N type thermoelectric elements on a lower substrate, and electrically connecting both the elements each other via a second planar electrode disposed on the lower substrate; and
electrically connecting cold sides of the P and N type thermoelectric elements each other via a first planar electrode disposed on an upper substrate.

To improve an efficiency of the thermoelectric module, it is required to enlarge a temperature difference between the hot and cold sides. For this purpose, the cold side of the thermoelectric elements is cooled by contacting them with a water cooled plate or a heat dissipation pad.

Patent Literature (PTL) 1 discloses a thermoelectric module, including hot and cold side substrates having trenches formed thereon, respectively, heat dissipation pads embedded in the trenches, respectively, a first planer electrode for electrically connecting cold sides of P and N type thermoelectric elements each other, and a second planer electrode for electrically connecting hot sides of the P and N type thermoelectric elements each other, in which the heat dissipation pads contact the first and second planar electrodes, respectively.

JP2013-26618A

Summary

The following analysis is given by the present invention.
Supplementing the water cooled plate or the dissipation pad in the thermoelectric module causes a problem that heat resistance is increased. In the case of the thermoelectric module of Patent Literature 1, new heat resistances are generated on a boundary disposed between the electrode and the heat dissipation pad, and a boundary disposed between the substrate and the heat dissipation pad. Furthermore, according to the thermoelectric module of Patent Literature 1, there is a problem that improvement effect of heat dissipation is limited, since the dissipation pads are embedded in the substrates. These problems cause reduction in a temperature difference between the hot and cold sides in the thermoelectric module.

Therefore, it is desired that a thermoelectric module has a smaller heat resistance and an excellent heat dissipation, and is capable of causing a larger temperature difference between a hot and cold sides of the thermoelectric module.

According to a first aspect of the present disclosure, there is provided a thermoelectric module, comprising:
a first thermoelectric element(s) having one of P and N type thermoelectric characteristics;
a second thermoelectric element(s) having the other of P and N type thermoelectric characteristics; and
a first electrode(s) configured to electrically connect between cold sides of the first and second thermoelectric elements, the first electrode(s) having an arch shape extending from the first and second thermoelectric elements so as to function as a heat sink.

Advantageous effects of Invention are mentioned below without limitation. Advantageous effects according to the thermoelectric module hereinabove mentioned are exemplified as follows:
(1) The first electrode(s) further serves as a heat sink, thereby reducing a number of components of the thermoelectric module, and lowering heat resistance;
(2) The first electrode(s) has the arch shape (i.e., partially looped shape or semi-looped shape), so that the first electrode(s) has a longer total length and a larger heat dissipation area;
(3) Increase in the large quantity of an electric power generation or capacity of heating and cooling is produced, as a temperature difference is increased due to the above effects of (1) and (2); and
(4) Flexibility of the first electrode(s) improves flexibility and design freedom. Therefore, the thermoelectric module according to the present disclosure is preferably applied to a case that the module is mounted on a curved surface (which is a heat source or dissipation surface).

Fig.1 is a schematic view illustrating a structure of a first electrode in a cold side of a thermoelectric module according to Exemplary Embodiment 1. Fig.2 is a schematic view illustrating one exemplary embodiment of a second electrode in a hot side of the thermoelectric module according to Exemplary Embodiment 1. Fig.3 is a schematic view illustrating another exemplary embodiment of the second electrode in the hot side, according to Exemplary Embodiment 1. Fig.4 is a schematic view illustrating one exemplary application (described as Exemplary Embodiment 2) using the thermoelectric module as shown in Fig.2. Fig.5 is a schematic view illustrating another exemplary application (described as Exemplary Embodiment 2) using the thermoelectric module as shown in Fig.3. Fig.6 is a schematic view illustrating one exemplary whole structure of a thermoelectric module according to Exemplary Embodiment 3. Fig.7 (A) to Fig.7 (I) provide a schematic view illustrating a variety of exemplary modifications (Exemplary Embodiment 4) as to a shape of the first electrode. Fig.8 is a schematic view illustrating one exemplary whole structure of the thermoelectric module according to Exemplary Embodiment 5, using the first electrode having a cross sectional shape as shown in Fig.7 (H). Fig.9 is a graph illustrating experimental results.

Hereinafter, one exemplary embodiment is explained, referring to the drawings. In addition, modifications and/or variations are indicated at the end of Description, since the understanding of the explanation of the consistent one exemplary embodiment would be disturbed when such modifications and/or variations are inserted in the explanation of the exemplary embodiment.
MODE 1: See the first aspect as herein-above mentioned.
MODE 2: The first and second thermoelectric elements have a columnar shape, wherein the first electrode(s) has one end connected to an end surface of the first thermoelectric element on the cold side thereof, and the other end connected to an end surface of the second thermoelectric element on the cold side thereof, and wherein the first electrode(s) is configured to extend in the arch shape above the end surfaces of the first and second thermoelectric elements on the cold sides thereof.
MODE 3: The first electrode(s) is projected from end surfaces of the first and second thermoelectric elements on the cold sides thereof by at least 3 mm.
MODE 4: The first thermoelectric element(s) has a rectangular cross-section.
MODE 5: The first electrode(s) comprises a plurality of electrodes.
MODE 6: The thermoelectric module further comprises a cover (accommodating housing) is configured to cover the thermoelectric module, wherein the first electrode(s) is exposed in a space defined between an inner surface of the cover (housing) and the first and second thermoelectric elements.
MODE 7: The thermoelectric module further comprises a third thermoelectric element(s) having a thermoelectric characteristic (conduction type) different from to that of the first thermoelectric element(s) and equivalent to that of the second thermoelectric element(s), and
a second electrode(s) configured to electrically connect between hot sides of the first and third thermoelectric elements, the second electrode(s) having an arch shape extending between the first and third thermoelectric elements so as to function as a heat sink.

For dissipating heat efficiently, it is essential to transfer the heat toward a high thermal conducting member having a large surface area, as well as to reduce heat resistance. When inserting a different kind material, e.g., the dissipation pad between a thermoelectric element and an upper substrate, as disclosed in Patent Literature 1, contactability between those members could be improved, however heat dissipation from the dissipation pad embedded in the upper substrate is low, thereby creating, new problem as to heat conductivity, durability and cost performance of the dissipation pad. In contrast, the first electrode(s) having the arch shape according to the present disclosure can overcome the above problem.

The first electrode(s) preferably arches over (and above) the first and second thermoelectric elements. Thus, interference between the first electrode(s) and the first and second thermoelectric elements is prevented, and heat dissipation from the first electrode is improved, even if many of the thermoelectric elements are arrayed as closely as possible.

The first electrode(s) is preferably formed in a curved or folded shape so as to have a large dissipation area or large space occupation, in particularly, preferably have a plurality of folded or inflexion points.

The second electrode(s) can be made of a planar electrode generally. If heat quantity input into the hot sides of thermoelectric elements is excessive, the second electrode(s) can be made of the arch shape electrode, as well as the first electrode(s). Accordingly, the input heat quantity can be restricted.

Materials of the thermoelectric elements are exemplified as follows: sillicide base, Si-Ge base, oxide base, Pb-Te base, TAGS base, La-Te base, filled Skutterudite base, Bi-Sb-Te-Se base, Zn₄Sb₃ base, Bi-Te base. For example, (Bi,Sb)₂Te₃ may be used to produce the P type thermoelectric element. For example, Bi₂(Te,Se)₃ may be used to produce the N type thermoelectric element.

The first and second electrodes are preferably composed of a material having a high thermal conductivity, a low electric resistance, and being capable of lowering heat resistance between the thermoelectric elements and those electrodes. For example, such material may include Cu, Al, Au, Ag, Pt and alloys thereof. Cu-Sn and Cu-Ni base materials may be used as the Cu alloy, for example.

The thermoelectric element(s) may be bonded with the electrode(s) via a plating surface(s) disposed thereon. Alternatively, the thermoelectric element(s) may be directly bonded with the electrode(s).

If the second electrode(s) on the hot side has a planar sheet shape, the second electrode(s) may be mounted on a waste heat source or a dissipation surface, for example, via an electrical insulation substrate, such as a ceramic substrate.

The first electrode(s) may be bonded with the first and second thermoelectric elements, using a process selected from heat bonding, ultrasonic bonding, brazing, adhering, and fastening with bolt and nut etc. The same may apply to the second electrode(s).

As to the waste heat source, a pipe through which high-temperature fluid flows, such as, an exhaust pipe of vehicle (e.g., a manifold made of stainless steel (SUS)), an internal combustion engine, and a furnace (e.g., a heat-treating furnace) are exemplified.

Hereinafter, one exemplary embodiment will be explained, referring to drawings.

<Exemplary Embodiment 1>
Referring to Fig.1, a thermoelectric module according to Exemplary Embodiment 1 comprises: a first thermoelectric element 1 having one of P and N type thermoelectric characteristics; a second thermoelectric element 2 having another of P and N type thermoelectric characteristics; and a first electrode 11 configured to electrically connect between low-temperature sides (Cold Side) of the first and second

thermoelectric elements

1,2. In the thermoelectric module, heat flux “Q” is generated, flowing from high-temperature sides (Hot Side) to the cold sides.

The first and second

thermoelectric elements

1,2 have a columnar shape. The first and second

thermoelectric elements

1,2 are arrayed in a manner that outer peripheral surfaces thereof are faced each other. The first electrode 11 has one end, i.e., a first bonding part 11a bonded with one end surface on the cold side of the first thermoelectric element 1. The first electrode 11 has the other end, i.e., a second bonding part 11b bonded with one end surface on the cold side of the second thermoelectric element 2.

The first electrode 11 has an arch shape extending from the first and second

thermoelectric elements

1, 2 so as to function as a heat sink. In particular, the first electrode 11 is configured to extend in the arch shape above the end surfaces of the first and second

thermoelectric elements

1, 2 on the cold sides thereof.

Advantageous effects according to the first electrode 11 are exemplified as follows:
(1) The first electrode 11 further serves as a heat sink, thereby reducing a number of components of the thermoelectric module, and lowering heat resistance (i.e, heat resistance through boundary surfaces between the components are lowered);
(2) The first electrode 11 has the arch shape (i.e., partial looped shape or semi-looped shape), so that the first electrode 11 has a longer total length and a larger heat dissipation area;
(3) The first electrode 11 arches in a space disposed over the first and second

thermoelectric elements

1, 2, the space being substantially apart from the first and second

thermoelectric elements

1, 2. Therefore, the first electrode has a high heat dissipation capability.

Next, a second electrode 21 on the hot side of the thermoelectric module is described.

Referring to Fig.2, a thermoelectric module according to Exemplary Embodiment 1 further comprises: a third thermoelectric element 3 having a thermoelectric characteristic different from that of the first thermoelectric element 1 and that of the second thermoelectric element 2; and a second electrode configured to electrically connect between the hot sides of the first and third

thermoelectric elements

1, 3.

The second electrode 21 on the hot sides could be made of a planar electrode which is generally used in the art of the thermoelectric module.
Alternatively, referring to Fig.3, the second electrode 21 on the hot sides may be made of an electrode having the same shape as the first electrode 11, i.e., the shape extending from the first and third

thermoelectric elements

1, 3. The second electrode 21 has one end, i.e., a third bonding part 21a bonded with one end surface on the hot side of the first thermoelectric element 1. The second electrode 21 has the other end, i.e., a forth bonding part 21b bonded with an end surface on the hot side of the third thermoelectric element 3.

The configuration of the electrodes as shown in Fig.3 is preferably applied to one case that heat quantity input into the hot sides of thermoelectric elements is excessive, and therefore, it is difficult to produce a suitable temperature difference, and another case the thermoelectric module have a mounted surface (i.e, a dissipation surface of a heat source) with a large curvature (see Fig. 5 below), etc.

<Exemplary Embodiment 2>
In Exemplary Embodiment 2, an exemplary case that the thermoelectric module is attached on a curved surface as a heat dissipation surface of a heat source is described.

Fig.4 illustrates one exemplary application, in which the planar electrode as shown in Fig.2 is used as a second electrode 21 on a hot side (Hot side). Referring to Fig.4, a thermoelectric module as shown in Fig.2 is attached on a heat dissipation surface being a curved surface, such as outer peripheral surface of a pipe through which a high temperature flow passes, via an electric insulating substrate 4. The substrate 4 has a tubular shape. The substrate 4 can be bonded with the heat dissipation surface 5 with an adhesive, brazing material, or a fastener. A second electrode 21 has a planar rigid body. In contrast, a first electrode 11 on a cold side (Cold Side) has a high flexibility due to its arched shape. Therefore, basic units of the thermoelectric module composed of the first, second and third thermoelectric elements 1-3, and the first and

second electrodes

11, 21 are easily arrayed circumferentially. Thus, the thermoelectric module is easily attached to the curved surface, even though the second electrode 21 disposed on the hot side has the rigid body and the planar shape.

Fig.5 illustrates another exemplary application, in which the arched electrode as shown in Fig.3 is used as a second electrode 21 disposed on a hot side. Different features between the one and another exemplary applications are described below, whereas, as to common features therebetween, the hereinabove mentioned can be referred to.

Referring to Fig.5, the thermoelectric module as shown in Fig.3 is attached to a dissipation surface 4 having a larger curvature than that shown in Fig.4, via an electric insulating substrate 4. The second electrode 21 disposed on a hot side (Hot Side) has an arched shape and a high flexibility, similar to a first electrode disposed on a cold side (Cold Side). Such thermoelectric module is suitable to be attached to a small diameter pipe.

<Exemplary Embodiment 3>
Fig.6 is a schematic view illustrating one exemplary whole structure of a thermoelectric module according to Exemplary Embodiment 3.

Referring to Fig.6, a thermoelectric module has a cover 6. The cover 6 is integrated on a substrate 4 so that the cover 6 and the substrate 4 form a housing (4, 6). On a cold side (Cold Side), many first electrodes 11 are accommodated and exposed in a space 6a defined in the cover 6a. That improves heat dissipation performance from the electrodes 11. To further enhance the heat dissipation performance, the cover is preferably provided with a hole(s), etc.

On a cold side (Cold Side), second electrodes 11 are mounted on a substrate 4. The second electrode may have a planar shape as shown in Fig.6 or the arch shape as shown in Fig.3.

When applying temperature difference to the thermoelectric module, it is possible to take out electric current generated between

terminals

7, 8 of the thermoelectric module. In contrast, when supplying the thermoelectric module with electric current between the

terminals

7,8, it is possible to conduct cooling and /or heating. Switching a current direction allows the first electrode of the thermoelectric module to be on the hot side or the cold side.

<Exemplary Embodiment 4>
Referring to Figs.7(A)-(I), a variety of shapes of a first electrode 11 are exemplified.

Referring to Figs.7(A)-(D), a first electrode 11 may have a circular arc shape, an elliptical-like shape, a rectangular-like shape, an ohm-like shape, or a corrugate-like shape. In this manner, the first electrode 11 preferably has an extending or enlarging shape above thermoelectric elements so as to allow the thermoelectric elements to be arrayed at a high density.

Referring to Fig.7(E), the first electrode 11 has a first and

second bonding parts

11a,11b arranged on a front side of the first electrode 11. Referring to Fig.7(F), the first electrode 11 has a first and

second bonding parts

11a,11b arranged on front and back sides of the first electrode 11, respectively. Arrangement positions of the first and

second bonding parts

11a, 11b are defined so as to prevent interference between the first electrodes 11.

Referring to Fig.7(G), a first electrode 11 has a rectangular cross-section. Therefore, the first electrode 11 has a ribbon-like shape as a whole. The first electrode 11 having such shape has a larger surface area relative to a thickness (cross-sectioned area) thereof, so that has an advantageous heat dissipation performance.
Referring to Fig.7(H), a first electrode 11 has a circular cross-section. The first electrode 11 having such shape is manufactured at a low cost and easily handled.

Referring to Fig.7(I), a first electrode 11 includes a plurality of a first electrodes 11. The plurality of the first electrodes 11 are connected between the first and second thermoelectric elements (see Fig.1) in parallel. The plurality of the first electrodes 11 has a larger total surface area due to their side surface area, compared to a single of electrode 11.

<Exemplary Embodiment 5>
Referring to Fig.8, one exemplary embodiment of a whole structure of a thermoelectric module, the first electrode 11 having a shape as shown in Fig.7(H) is described. In Fig.8, the first electrode 11 has a sufficiently large cross-sectional area, even though having a linear shape. Therefore, the first electrode 11 can function as a heat sink. In addition, an aggregation including a plurality of the first electrodes 11 has a high performance of heat dissipation, due to arraying at high density arrangement of those electrodes 11. Furthermore, arrangement directions of the second electrodes 21 (longitudinal direction of the second electrodes 21) are different between a central region and an end region of the thermoelectric module (thereby the arrangement directions in the central region are orthogonal to that in the end region), in order to integrally mount those thermoelectric elements 1-3 at a high density, and to electrically connect those thermoelectric elements 1-3 in series.

Thermoelectric modules having a structure as shown in Fig.1 or 2 are prepared. Temperature difference generated in the thermoelectric module was measured by varying a length of a first electrode 11. The first electrode 11 is bonded with the first and second

thermoelectric elements

1, 2 through a ultrasonic bonding process. When using an ultrasonic bonding process, the first and second

thermoelectric elements

1, 2 are preferably plated. When using a laser bonding process, such plating is optional. A ribbon-like electrode mainly made of cupper is used as the first electrode 11. The measured first electrode 11 has a thickness of 0.2mm, a width of 2mm, and a length of selected one of 0, 10, 20, and 40mm. The measured first electrode 11 has first and second bonding part areas of 0.4*0.4mm, respectively. In the first electrode 11, an arch scale and a heat dissipation area are increased as the length of the first electrode increases. Referring to Fig.1 or Fig.2, the length of "0mm" means that the first electrode 11 has a total length only including lengths of the first and second bonding parts, and a clearance to be set so as to prevent the first and second thermoelectric elements from directly contact each other, i.e., the first electrode 11 has no arch shape. A hot side of the thermoelectric module was contacted a hot plate heated at a temperature of 220 degrees Celsius, the temperature difference hereinabove mentioned was measured.

Referring to an experimental result as shown in Fig.9, the measured temperature difference DT was increased, as the first electrode 11 sets longer, and thereby having a lager arch scale. The temperature difference generated in a case using the arched first electrode 11 having a length of 20mm was larger than that generated in a case using the planar first electrode 11 having a length of 0mm, by approximately 20 degrees Celsius. The temperature difference generated in a case using the arched first electrode 11 having a length of 40mm was larger than that generated in a case using the planar first electrode 11 having the length of 0mm, by approximately 27 degrees Celsius. Also, according to the first electrode 11 having a length of 10mm and projecting from the cold side end of the first and second thermoelectric elements by at least 3mm (about a length 10mm/3.14), a temperature difference of approximately 10 degrees Celsius was generated. Therefore, it has been recognized that such first electrode sufficiency functions as a heat sink. Furthermore preferably, the first electrode 11 projects by at least 6, 9, or 10mm, or more.

In the thermoelectric module, the voltage gain is proportional to the temperature difference. The electric power is proportional to square of the voltage. Consequently, the electric power obtained in the case of using the arched first electrode 11 having the length of 40mm was 1.5 times higher of that obtained in the case of using the planar first electrode 11 having the length of 0mm. The reason for improvement such thermoelectric efficiency is explained below.
That is, the reason is believed as follows:
(1) The first electrode 11 is directly bonded with the first and second

thermoelectric elements

1, 2, thereby lowering heat resistance between the first electrode 11, and the first and second

thermoelectric elements

1, 2;
(2) The first electrode 11 is exposed in the space, and therefore, heat resistance between the first electrode 11 and the space is low;
(3) The first electrode 11 has a larger heat dissipation area.

An upper limit of the length and/or surface area of the first electrode 11 are preferably set, depending on interference between the first electrodes 11, interference of the first electrode 11 with the first and second

thermoelectric elements

1, 2, and electric resistance thereof. The first electrode 11 preferred has a ratio of "surface area"/"section area" ranging from 100 to 400. An example of a formula for calculating a preferable ratio of "surface area"/"cross-sectional area" is described as follows:
2 (as to top and bottom surfaces, note: both sides and both ends surfaces of the first electrode are ignored for simplification) * (width of 2mm * length of 10-40mm) / (width of 2mm * t of 0.2mm).

<Industrial Applicability>
The thermoelectric module according to the present disclosure is applied to an electric power generator utilizing "Seebeck Effect", and a cooling or heating device utilizing "Peltier Effect". The thermoelectric module according to the present disclosure is applied to both cases that the module is mounted on a flat or curved surface.

The entire disclosures of the hereinabove Patent Literatures are incorporated herein by reference thereto. Modifications and adjustments of the exemplary embodiment(s) are possible within the scope of the overall disclosure (including the claims) of the present disclosure and based on the basic technical concept of the present disclosure. Various combinations and selections of various disclosed elements (including each element of each claim, each element of each exemplary embodiment, each element of each drawing, etc.) are possible within the scope of the present disclosure. That is, the present disclosure of course includes various variations and modifications that could be made by those skilled in the art according to the overall disclosure including the claims and the technical concept. Particularly, any numerical range disclosed herein should be interpreted that any intermediate values or subranges falling within the disclosed range(s) are also concretely disclosed even without explicit recital thereof.

1 First thermoelectric element
2 Second thermoelectric element
3 Third thermoelectric element
4 Substrate, Lower substrate
5 Heat dissipation surface (Waste heat source)
6 Cover
(4, 6) Housing
7, 8 Terminal
11 First electrode, Cold side electrode
11a, 11b First and Second joint portions
21 Second electrode, Hot side electrode
21a, 21b Third and Fourth joint portions
Cold Side Lower temperature side
Hot Side Higher temperature side
Q Heat flow, Heat flux

Claims

A thermoelectric module, comprising:
a first thermoelectric element(s) having one of P and N type thermoelectric characteristics;
a second thermoelectric element(s) having the other of P and N type thermoelectric characteristics; and
a first electrode(s) configured to electrically connect between cold sides of the first and second thermoelectric elements, the first electrode(s) having an arch shape extending from the first and second thermoelectric elements so as to function as a heat sink.
The thermoelectric module according to Claim 1, wherein
the first and second thermoelectric elements have a column shape, wherein
the first electrode(s) has one end connected to an end surface of the first thermoelectric element on the cold side thereof, and the other end connected to an end surface of the second thermoelectric element on the cold side thereof, and wherein
the first electrode(s) is configured to extend in the arch shape above the end surfaces of the first and second thermoelectric elements on the cold sides thereof.
The thermoelectric module according to Claim 1 or 2, wherein
the first electrode(s) is projected from end surfaces of the first and second thermoelectric elements on the cold sides thereof by at least 3 mm.
The thermoelectric module according to any one of Claims 1-3, wherein
the first thermoelectric element(s) has a rectangular cross-section.
The thermoelectric module according to any one of Claims 1-4, wherein
the first electrode(s) comprises a plurality of electrodes.
The thermoelectric module according to any one of Claims 1-5, further comprising a cover configured to cover the thermoelectric module, wherein the first electrode(s) is exposed in a space defined between an inner surface of the cover and the first and second thermoelectric elements.
The thermoelectric module according to any one of Claims 1-6, further comprising:
a third thermoelectric element(s) having a thermoelectric characteristic different from to that of the first thermoelectric element(s) and equivalent to that of the second thermoelectric element(s), and
a second electrode(s) configured to electrically connect between hot sides of the first and third thermoelectric elements, the second electrode(s) having an arch shape extending between the first and third thermoelectric elements so as to function as a heat sink.