JPH09260730A - Thermoelectric module and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoelectric module manufacturing method with which a thermoelectric module can be manufactured by a simple process. SOLUTION: A P-type thermoelectric element 16, which is integrally formed with an electrode board on the upper and the lower sides, and an N-type thermoelectric element 18, are arranged alternately with a predetermined gap between them; the P-type thermoelectric element 16 and the N-type thermoelectric element 18 are electrically connected in series, and sub-modules 14 are formed. Then, each sub-module is arranged on parallel in such a manner that P type-to-P type are not adjacently arranged or N-type-to-N type are not arranged adjacently, and sub-modules and are electrically connected in series.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric module and its manufacturing method.

[0002]

2. Description of the Related Art A thermoelectric module is composed of a p-type thermoelectric element and an n-type thermoelectric element.
Type thermoelectric elements are joined so as to be electrically connected in series via an electrode plate. When a temperature difference is applied between the junctions of the pn element pair, a potential difference is generated, and a current flows between the junctions. And has the property of absorbing or generating heat depending on the direction of the current. The former property is called the Seebeck effect, which has been developed for thermoelectric power generation, such as power generation by waste heat from refuse incinerators, and the latter property is called the Peltier effect, for example, constant temperature equipment in semiconductor manufacturing processes, electronic devices It is widely used for thermoelectric cooling such as cooling.

A conventional method of manufacturing such a thermoelectric module will be described with reference to FIG. First, the p-type and n-type thermoelectric materials are once melted in a quartz ampoule, and the ingot gradually crystallized from one direction is cut into an appropriate size (for example, several mm square), as shown in the figure, A p-type thermoelectric material compact (90) and an n-type thermoelectric material compact (91) are obtained. On both sides of the thermoelectric material molded body (90) (91), Ni for enhancing the bondability is formed.
The plating layers 92, 92 are applied, and the solder plating layers 94, 94 are further applied on the Ni plating layer. Next, the electrodes (98)
Is a ceramic substrate (9
It is formed by directly patterning Cu on 6).
After the p-type thermoelectric material molded body (90) and the n-type thermoelectric material molded body (91) are alternately arranged on the Cu electrode (98) of the ceramic substrate (96) corresponding to the patterning position, the thermoelectric material is molded. The ceramic substrate (96) on which the Cu electrodes (98) are patterned is placed on the material compacts (90) (91). When this is placed in a heater and heated, the solder (94) (94) melts and the molded body
Ni plating layers (92) and (92) of (90) and (91) and the ceramic substrate (9
6) The Cu electrodes (98) and (98) of (96) are joined. FIG.
In No. 1, the thermoelectric material molded bodies (90) and (91) show only one p-type and one n-type, but there are usually many, depending on the required performance of the thermoelectric module.

In the conventional manufacturing method, the bonding between the p-type and n-type thermoelectric material compacts and the electrodes is performed by soldering when assembling the thermoelectric module, so that the small thermoelectric material compacts are correctly arranged at the patterning position. A lot of man-hours were required for the work and the soldering process.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel method for manufacturing a thermoelectric module in order to simplify the manufacturing process of the thermoelectric module.

[0006]

A method of manufacturing a thermoelectric module according to the present invention comprises preparing a plurality of p-type and n-type thermoelectric elements in which thermoelectric members are bonded between opposing first and second electrode plates. , A p-type thermoelectric element is formed so that a predetermined gap is formed between adjacent p-type and n-type thermoelectric elements, and each first electrode plate is located on the same plane and each second electrode plate is located on the same plane. Elements and n-type thermoelectric elements are alternately arranged, and the first electrode plate and the second electrode plate that are adjacent to each other with a gap therebetween are alternately brazed to electrically connect the p-type thermoelectric element and the n-type thermoelectric element. It is formed by connecting in series.

After the thermoelectric module is manufactured, it is possible to connect to another thermoelectric module or the like by connecting the connecting terminals to the electrode plate which is the base end and the electrode plate which is the end of the electrical series circuit.

Further, the strength of the thermoelectric module can be increased by filling the gap between the thermoelectric elements with a coating material. Examples of the coating material include resin, ceramic, gypsum, and cement. It is desirable to fill the gap with the coating material by coating the entire thermoelectric module. After covering the entire outer circumference, the electrode plate is surface-ground until it has a predetermined thickness, whereby a precisely controlled flat surface can be obtained. Thus, when connecting and using a plurality of thermoelectric modules, the thickness of the thermoelectric modules can be made uniform. Since resin, ceramics, gypsum and cement have an electrical insulation function, if you want to use the coating material as an insulating material at the same time, the coating layer should have a thickness that does not affect the heat transfer function and should be applied to the electrode surface. It can also be present.
If the covering material is formed so as to project to the side of the thermoelectric module, a mounting hole or the like for mounting the heat exchanger can be formed in the projecting portion.

As another method for manufacturing a thermoelectric module according to the present invention, the same number of p-type and n-type thermoelectric elements in which thermoelectric members are joined between opposing elongated first and second electrode plates are prepared and adjacent to each other. A predetermined gap is formed between the p-type and n-type thermoelectric elements, and each first electrode plate is located on the same plane, and each second electrode plate is located on the same plane. Type thermoelectric elements are alternately arranged, and the first electrode plate and the second electrode plate that are adjacent to each other with a gap therebetween are alternately brazed to electrically connect the p-type thermoelectric element and the n-type thermoelectric element in series. By cutting the thermoelectric elements at predetermined intervals in the longitudinal direction, a plurality of sub-modules in which the p-type and n-type thermoelectric elements are electrically connected in series are formed, and the sub-modules are arranged at every left and right positions. Swap the adjacent sub-modules The arranged to lie, as sub-modules of the plurality rows are electrically connected in series, p-type thermoelectric element at an end position of the adjacent sub-module and the n
It can also be formed by brazing the electrode plate of the thermoelectric element. A typical brazing material is solder.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The thermoelectric material forming the thermoelectric member is not particularly limited, and known materials can be used.
As an example, as a p-type thermoelectric material, (Bi ₂ Te ₃ )
_1-x (Sb ₂ Te ₃ ) _{x wherein} x is 0.70 to 0.85. As an n-type thermoelectric material, (Bi ₂ Te 3)
₃ ) _1-x (Bi ₂ Se ₃ ) _{x wherein} x is 0.05 to 0.15.

The p-type thermoelectric element (16) and the n-type thermoelectric element (18) are
As shown in FIG. 1, a p-type thermoelectric member (20) and an n-type thermoelectric member (2) are provided between the opposing first electrode plate (26) and second electrode plate (28).
It is an element in which 2) is sandwiched and bonded. Although the illustrated thermoelectric element has an elongated rectangular shape, it is not limited to this shape, and a square plate-shaped body, a cubic body, or the like can of course be used. The p-type and n-type thermoelectric elements (16) (18) are thermoelectric members in advance.
(20) After forming the molded body of (22) and plating the both surfaces of the molded body with Ni, the first electrode plate (26) and the second electrode plate (28) are provided on each surface with a brazing material such as solder ( It can be obtained by joining (not shown). Alternatively, as shown in FIG. 9, the first electrode plate (26), the thermoelectric material powder (24), and the second electrode plate are placed in the mold (50).
It is also possible to obtain the electrode plates (26) and (28) simultaneously bonded to both surfaces of the thermoelectric material when the thermoelectric material powder (24) is pressure-sintered in the stacking direction after the layers (28) are laminated in order. In this case, in order to obtain the elongated thermoelectric element shown in FIG. 1, after forming a rectangular plate-shaped molded body, as shown in FIG. 10, it may be cut in parallel with one side.

As for the electrode plates (26) and (28), it is desirable to use a Ni plate or a Cu plate plated with Ni for the thermoelectric material of Bi-Te alloy. The thickness of the plating layer is preferably about 20 μm or more.
Besides this, a Cu plate on which molybdenum (Mo) or titanium (Ti) is deposited may be used.

When the thermoelectric element is manufactured by the hot pressing method shown in FIG. 9, it is desirable to use the electrode plates (26) and (28) having through holes penetrating the plate surfaces. this is,
By filling the through-holes with the thermoelectric material powder and performing pressure sintering, not only the adhesion strength in the plate surface direction of the electrode plate is increased, but as shown in FIG. 1, for example, a p-type thermoelectric element (16 )
This is because if the electrode plate of No. 2 is a circular hole (30) and the electrode plate of the n-type thermoelectric element (18) is a square hole (32), it will also be an identification mark of the thermoelectric element.

As the form of the thermoelectric module to be produced,
As shown in FIG. 2 or FIG. 3, there may be mentioned a single row structure thermoelectric module (10) in which a p-type thermoelectric element (16) and an n-type thermoelectric element (18) are electrically connected in series via an electrode plate. . Moreover, as shown in FIG. 5, a p-type thermoelectric element (16) and an n-type thermoelectric element
The sub-module (14) is a thermoelectric module having a single-row structure in which (18) is electrically connected in series via electrode plates, and the sub-module (14) is a thermoelectric module (12) electrically connected in series in a plurality of rows. ) Can be mentioned.

First, a method for manufacturing the thermoelectric module having the single-row structure shown in FIGS. 2 and 3 will be described. As shown in FIG. 1, first and second p-type and n-type thermoelectric elements (16) and (18), in which thermoelectric members are respectively joined between opposing elongated first and second electrode plates (26) and (28), are provided. The electrode plates (26) are located on the same plane, the second electrode plates (28) are located on the same plane, and the p-type and n-type thermoelectric elements are arranged alternately. The number of thermoelectric elements may be appropriately determined as needed. In the illustrated embodiment, the circular holes (3) are formed in the electrode plates (26) and (28) of the p-type thermoelectric element (16).
0), square holes (32) in the electrode plates (26) (28) of the n-type thermoelectric element (18)
Are formed.

As shown in FIG. 4, adjacent p-type thermoelectric elements (1
A plate-like spacer (36) made of epoxy resin or the like is inserted between 6) and the n-type thermoelectric element (18) to form parallel gaps (42) (44) between adjacent electrode plates. To do. The spacer (36) aligns the thermoelectric elements parallel to each other at a predetermined interval and prevents the brazing material from adhering to an unnecessary portion when brazing the electrodes.

Next, the first electrode plates (26) and (26) adjacent to each other with the odd-numbered gaps formed by the spacers (36) interposed therebetween, and the second electrode plates (28) adjacent to each other with the even-numbered gap interposed therebetween. ) (2
8) Join the electrodes alternately with a brazing material (34) such as solder to electrically connect the electrode plates. More specifically, referring to FIG. 4, the leftmost (odd number) gap (42) in FIG.
When the first electrode plates (26) and (26) sandwiching between are brazed together,
Next, the electrode plates (28) (2
8) Braze each other. Next is the third from the left
The brazing is repeated in the order of the first electrode plates (26) and (26) sandwiching the (odd number) gap (42). The brazing may be performed alternately from the ends, or may be performed on one side or on both sides simultaneously. From the viewpoint of workability,
After treating one side, it is desirable to turn it over and treat the other side. When the spacer (36) is removed, a thermoelectric module in which the p-type thermoelectric element (16) and the n-type thermoelectric element (18) are electrically connected in series is formed as shown in FIG.

The thermoelectric elements connected by the brazing material (34) are cut at predetermined intervals in the longitudinal direction of the thermoelectric elements as shown by the alternate long and short dash lines (51) and (52) in FIG. Once removed, the elongated thermoelectric module (10) as shown in FIG.
Can be produced. In the thermoelectric module (10), terminals (40a) and (40b) are attached to an electrode plate (27) serving as a base end of an electrical series circuit and an electrode plate (29) serving as a terminal end, respectively.

In order to reinforce the thermoelectric module (10), it is desirable to fill the space after removing the spacer (36) with the resin (38). Further, when the surface of the electrode plate is covered with the resin (38), it can also function as an electric insulating material of the thermoelectric module (10). For this reason, spacers (36)
After removing and removing the terminal (40), as shown in FIG. 5, a resin (38) is poured to cover the entire thermoelectric module (10). When the thermoelectric module (10) is covered with the resin (38), the spacer (36) does not necessarily have to be removed, and the resin may be poured over the spacer. After that, the resin (38) is removed by surface grinding or cutting until the surface of the electrode plate is exposed as shown by the chain double-dashed lines (52) and (52) in FIG. By this step, the smoothness of the thermoelectric module can be increased and the thickness of the thermoelectric module can be adjusted with high accuracy.
When it is necessary to make the resin (38) act as an insulating material, the surface of the resin is ground or cut as necessary to a thickness that does not adversely affect the heat transfer function. If the resin is molded so as to project laterally of the thermoelectric module, a mounting hole (39) (see FIGS. 5 and 8) for mounting the heat exchanger can be formed in the projecting portion. Ceramic can be used instead of resin. In this case, a ceramic powder dissolved in a solvent may be poured into a thermoelectric module mold and then dried. When the thermoelectric module is used at a high temperature, it is desirable to use a ceramic having excellent heat resistance.

Next, a method of manufacturing the thermoelectric module (12) having a multi-row structure shown in FIG. 6 will be described. As shown in FIG. 4, the soldered elongated p-type and n-type thermoelectric elements are cut into a plurality of rows along the alternate long and short dash line (51). The cut thermoelectric modules in each row are hereinafter referred to as "submodules (14)". One sub-module (14) has the same shape as the thermoelectric module (10) shown in FIG. 3 before the terminals (40a) and (40b) are attached.

Referring to FIG. 6, among the submodules (14) arranged in a plurality of rows, the left and right positions of the submodules located in an even row are interchanged. Similar to the above, a plate-like spacer made of resin or the like is inserted between adjacent sub-modules, and arranged so that a parallel gap (46) exists between the adjacent sub-modules. The sub-module (14) may replace the odd columns.

Next, the electrode plates at one end of the adjacent sub-modules (14) (14) are electrically connected in series by the solder (34) to electrically connect all the sub-modules (14) as a whole. By connecting in series, the thermoelectric module (12) having a multi-row structure shown in FIG. 6 can be manufactured. More specifically, the connection position of the adjacent sub-modules by the solder (34) will be described in more detail.
The second and third rows are connected at the left end (see FIG. 8), the third and fourth rows are again connected at the right end (see FIG. 6), thus the right and left Connected at alternating ends of.
When the thermoelectric module (12) is manufactured in this manner, as in the case of the method of manufacturing the thermoelectric module of FIG. 2 or 3, the electrode plate (27) (FIG. It is desirable to attach terminals (40a) and (40b) to the terminal electrode plate (29) (see FIG. 8), respectively, and to cover the entire thermoelectric module with resin (38) or ceramic. After coating, appropriate cutting processing and, if necessary, exposure processing of the electrode plate surface are performed to obtain a plurality of rows of thermoelectric modules as shown in FIGS. 7 and 8. Further, the protruding portion of the resin (38) can be appropriately provided with a mounting hole (39) to the heat exchanger, as in the above-mentioned embodiment.

[0023]

According to the method for manufacturing a thermoelectric module of the present invention, the steps can be simplified. In particular, when the thermoelectric module having a so-called multi-row structure shown in FIGS. 7 and 8 is manufactured, the thermoelectric element can be handled in the elongated shape until the final assembly is completed, so that the workability is extremely good.

[Brief description of drawings]

FIG. 1 is a perspective view when p-type thermoelectric elements and n-type thermoelectric elements are alternately arranged.

FIG. 2 is a perspective view when brazing is performed with a spacer sandwiched between adjacent thermoelectric elements.

3 is a perspective view of a thermoelectric module obtained by cutting along the alternate long and short dash line in FIG.

FIG. 4 is an explanatory view of a method for manufacturing the thermoelectric module shown in FIGS. 2 and 3.

FIG. 5 is a cross-sectional view of a thermoelectric module coated with resin.

FIG. 6 is a perspective view of a thermoelectric module having a multi-row structure in which sub-modules are arranged side by side and brazed.

FIG. 7 is a perspective view of a thermoelectric module having a multi-row structure in which, after being coated with resin, excess portions are cut and the upper surface of the electrode plate is ground or cut.

8 is a perspective view of the thermoelectric module shown in FIG. 7 when observed from a position different from FIG.

FIG. 9 is a cross-sectional view of a hot pressing mold that contains an electrode plate and thermoelectric material powder.

FIG. 10 is a perspective view of a thermoelectric element sintered by hot pressing.

FIG. 11 is a cross-sectional view showing a pn element pair of a conventional thermoelectric module.

[Explanation of symbols]

 (10) Thermoelectric module with single-row structure (12) Thermoelectric module with multi-row structure (14) Sub-module (16) P-type thermoelectric element (18) N-type thermoelectric element

Claims (5)

[Claims] 1. A method of manufacturing a thermoelectric module in which a p-type thermoelectric element and an n-type thermoelectric element are electrically connected in series, wherein a thermoelectric member is bonded between opposing first and second electrode plates. Prepare a plurality of p-type and n-type thermoelectric elements,
A p-type thermoelectric element and an n-type thermoelectric element so that a predetermined gap is formed between the mold and the n-type thermoelectric element, and each first electrode plate is located on the same plane and each second electrode plate is located on the same plane. The thermoelectric elements are alternately arranged in parallel, and the first electrode plate and the second electrode plate that are adjacent to each other with a gap therebetween are alternately brazed, and the p-type thermoelectric element and the n-type thermoelectric element are electrically connected in series. A thermoelectric module manufacturing method comprising: forming a thermoelectric module. 2. A method of manufacturing a thermoelectric module in which a p-type thermoelectric element and an n-type thermoelectric element are electrically connected in series, wherein a thermoelectric member is bonded between opposing elongated first and second electrode plates. The same number of p-type and n-type thermoelectric elements are prepared, a predetermined gap is formed between adjacent p-type and n-type thermoelectric elements, and each first electrode plate is on the same plane, and each second electrode The p-type thermoelectric elements and the n-type thermoelectric elements are alternately arranged in parallel so that the electrode plates are located on the same plane, and the first electrode plate and the second electrode plate that are adjacent to each other with a gap therebetween are alternately brazed. Then, the p-type thermoelectric element and the n-type thermoelectric element are electrically connected in series, and the p-type thermoelectric element and the n-type thermoelectric element are electrically connected in series by cutting the thermoelectric element at predetermined intervals in the longitudinal direction. Multiple sub-modules are formed, and every other sub-module is The sub-modules are arranged so that adjacent sub-modules have a predetermined gap, and the p-type thermoelectric elements located at the end positions of the adjacent sub-modules are electrically connected in series. A method of manufacturing a thermoelectric module, characterized in that a thermoelectric module is formed by brazing an element and an electrode plate of an n-type thermoelectric element. 3. The method of manufacturing a thermoelectric module according to claim 1, wherein the thermoelectric module is coated with a coating material. 4. After coating the thermoelectric module with a coating material,
4. The method of manufacturing a thermoelectric module according to claim 3, wherein surface grinding is performed until the electrode plate is exposed and the thermoelectric module has a predetermined thickness. 5. A pair or a plurality of pairs of p-type and n-type thermoelectric elements in which a thermoelectric member is bonded between opposing first and second electrode plates are provided for each of the p-type and n-type thermoelectric elements. One electrode plate is arranged in parallel so that the second electrode plates are located on the same plane and the respective second electrode plates are located on the same plane, and the p-type thermoelectric element and the n-type thermoelectric element are adjacent to each other so that they are electrically connected in series. A thermoelectric module in which first electrode plates and second electrode plates are alternately joined with a brazing material.