JP2013214635A - Thermoelectric conversion module and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoelectric conversion module and manufacturing method therefor, capable of achieving low module cost per power generation amount by facilitating work for alternately arraying thermoelectric elements and preventing degradation in power generation efficiency.SOLUTION: The thermoelectric conversion module comprised of a plurality of p-type thermoelectric elements and a plurality of n-type thermoelectric elements, which are alternately arrayed and electrically connected in series, includes a spacer member provided in a space surrounded by the plurality of thermoelectric elements.

Description

  The present invention relates to a thermoelectric conversion module and a manufacturing method thereof.

  The thermoelectric conversion module is applied in two ways: temperature control using the Peltier effect and power generation using the Seebeck effect. The former is used for temperature control, and it has become indispensable for cooling a laser oscillator due to the spread of optical communication in addition to portable refrigerators. On the other hand, for the power generation element using the latter Seebeck effect, a power generation system of several watts to several tens of watts using industrial waste heat has been studied, but there are problems such as expensive modules per amount of power generation The current situation is that it has not been put to practical use.

  As a conventional method for manufacturing the thermoelectric conversion module 100, as shown in FIG. 4, a plurality of element fitting holes 402 larger than the outer diameter of the P-type and N-type thermoelectric conversion elements 101 are arranged on an insulating substrate 401. The thermoelectric conversion elements 101 are alternately inserted through the element fitting holes 402 and arranged.

  Next, using the support sheet 404 in which the element through holes 403 are formed at positions corresponding to the arrangement positions of the thermoelectric conversion elements 101 that are through-fitted into the element fitting holes 402 of the insulating substrate 401, the elements of the support sheet 404 are used. The thermoelectric conversion element 101 is press-fitted into the through-hole 403 and provided so as to cover the insulating substrate 401 from above.

  In this manner, the thermoelectric conversion element 101 is supported and fixed to the insulating substrate 401, and the P-type and N-type thermoelectric conversion elements 101 are spaced from each other on one end side and the other end side in the penetration direction to the element fitting hole 402. In some cases, a plurality of electrodes 405 are provided to electrically connect the thermoelectric conversion elements 101 (for example, see Patent Document 1).

  However, in the manufacturing method as described above, the P-type and N-type thermoelectric conversion elements 101 need to be alternately fitted through the element fitting holes 402 arranged in the insulating substrate 401. Further, it is also necessary to press-fit the thermoelectric conversion element 101 into the element through-hole 403 provided in the support sheet 404 covered from the upper side of the insulating substrate 401 and to support and fix it. For this reason, the work requires a lot of labor and time, which is not only suitable for mass production but also has a problem that the module price per unit of power generation becomes high.

  As a manufacturing method for solving this problem, as shown in FIG. 5, a plurality of rod-shaped P-type and N-type thermoelectric conversion elements 101 are arranged alternately so that a certain gap exists between the thermoelectric conversion elements. After that, a resin is filled in a gap existing between the P-type and N-type thermoelectric conversion elements 101 to form an integrated block 302. Then, electrodes 405 for alternately electrically connecting the P-type and N-type thermoelectric conversion elements in series are formed on the cut surfaces of the block pieces obtained by cutting the block 302 to a predetermined thickness.

  Thereafter, in the manufacturing method of the thermoelectric conversion module 100 in which the heat-resistant adhesive is applied to the gap between the electrodes, the height of the heat-resistant adhesive applied to the gap between the electrodes is higher than that of the electrode surface. In some cases, a gap layer is formed between the contact surface with the heat source of the module and the applied heat-resistant adhesive when the thermoelectric conversion module 100 is used (see, for example, Patent Document 2).

JP 2006-032849 A JP 2009-076604 A

  However, in the above-described conventional configuration, when generating power using exhaust heat by the thermoelectric conversion module, a gap layer is formed between the contact surface with the heat source and the applied heat-resistant adhesive. Since a part of the resin passes through the resin portion existing between the electrodes, there is a problem that the power generation efficiency is lowered accordingly.

  The present invention solves the above-described conventional problems by simplifying the work of alternately arranging P-type and N-type thermoelectric conversion elements and preventing a decrease in power generation efficiency due to a resin portion existing between the electrodes. An object of the present invention is to provide a thermoelectric conversion module having a low module price per power generation amount and a method for manufacturing the same.

  In order to achieve the above object, the thermoelectric conversion module of the present invention is characterized by the following configuration.

  [1] In a thermoelectric conversion module including a plurality of P-type thermoelectric conversion elements and a plurality of N-type thermoelectric conversion elements that are alternately arranged and electrically connected in series, a spacer is provided in a space surrounded by the plurality of thermoelectric conversion elements. Arranged members.

  [2] In the above [1], the space surrounded by the plurality of thermoelectric conversion elements is filled with an adhesive.

  [3] In the above [1] or [2], the spacer member is made of an insulator.

  [4] In the above [3], the insulator is rod-shaped glass.

  [5] In the above [1] to [4], a gap is provided between two adjacent thermoelectric conversion elements and the spacer member.

  [6] In the above [1] to [5], the spacer member has a cylindrical shape.

  [7] In the above [1] to [6], the number of thermoelectric conversion elements adjacent to one spacer member is four.

  [8] In the above [1] to [6], the number of thermoelectric conversion elements adjacent to one spacer member is three.

  Moreover, the manufacturing method of the thermoelectric conversion module of this invention has the following processes as the characteristics.

[9] A first step of preparing a jig for arranging thermoelectric conversion elements, and alternately arranging P-type and N-type thermoelectric conversion elements inside the jig;
A second step of arranging a spacer member in a recess formed by the plurality of thermoelectric conversion elements;
A third step of applying an adhesive to the surface of the spacer member;
A fourth step of repeating the second and third steps until the predetermined number of arrangements, and then curing the adhesive to form a block;
And a fifth step of slicing the block and forming wiring so that the P-type and N-type thermoelectric conversion elements are sequentially connected in series.

  As described above, according to the thermoelectric conversion module and the method of manufacturing the same of the present invention, the operation of alternately arranging thermoelectric conversion elements is simple, and the module price per power generation amount is low by preventing a decrease in power generation efficiency. A thermoelectric conversion module can be provided. In addition, the presence of the spacer can provide a thermoelectric conversion module having high strength and high long-term reliability.

Cross-sectional view of thermoelectric conversion module according to an embodiment of the present invention Enlarged view of the vicinity of the spacer in the embodiment of the present invention The figure which shows the manufacturing method of the thermoelectric conversion module in embodiment of this invention Sectional drawing of the conventional thermoelectric conversion module described in patent document 1 The figure which shows the manufacturing method of the conventional thermoelectric conversion module described in patent document 2

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a thermoelectric conversion module according to an embodiment of the present invention, and FIG. 2 is an enlarged view of the vicinity of a spacer in FIG.

  1 and 2, the thermoelectric conversion element 101 is made of a columnar thermoelectric conversion material 103 surrounded by a cylindrical insulator 102. As the insulator 102, for example, a glass tube can be used. Among them, it is preferable to use a Pyrex (registered trademark) glass tube because of its high softening point. Further, as the thermoelectric conversion material 103, for example, a Bi—Te alloy can be used.

  Further, a spacer 104 having a function of adhering the thermoelectric conversion elements 101 exists at a position surrounded by the four adjacent thermoelectric conversion elements 101. As the spacer 104, as shown in FIG. 2A, an insulator 106 whose surface is covered with an adhesive 105, or a rod-like adhesive as shown in FIG. 2B can be used. Further, as the insulator 106 whose surface is covered with the adhesive, by using an inorganic material or the like that does not soften even at a high temperature, deformation during use of the thermoelectric conversion module 100 can be prevented, and long-term reliability is improved.

  Moreover, when the same material as the cylindrical insulator 102 of the thermoelectric conversion element 101 is used as the insulator 106 whose surface is coated with an adhesive, when the thermoelectric conversion module 100 is used, Since there is no difference in thermal expansion, the thermoelectric conversion module 100 is not easily destroyed, and long-term reliability is further improved.

  One spacer 104 includes four thermoelectric conversion elements 101 that are closest to each other. Among the four thermoelectric conversion elements 101, an adhesive or the like is provided between at least two adjacent thermoelectric conversion elements 101 and the spacer 104. Has a non-existent space 201 (sometimes referred to as a “gap”). Thereby, when using the thermoelectric conversion module 100, the heat conduction from the surface (high temperature surface) which contact | connects the heat source of the thermoelectric conversion module 100 to a low temperature surface can be suppressed, and the fall of power generation efficiency can be suppressed.

  Next, an example of the manufacturing method of the thermoelectric conversion module 100 of this Embodiment is demonstrated with reference to FIG.

  First, a cylindrical insulator 102 is filled with a thermoelectric conversion material 103 to form a cylindrical thermoelectric conversion element 101 (not shown). As a filling method, there are a method in which a solid thermoelectric conversion material 103 is placed in a cylindrical insulator 102 and heated and melted, a method in which a molten thermoelectric conversion material 103 is caused to flow into the cylindrical insulator 102, and the like. In addition, after the cylindrical thermoelectric conversion material 103 is formed, the cylindrical insulator 102 may be removed. However, if the cylindrical insulator 102 remains around the thermoelectric conversion material 103, it is prevented that the thermoelectric conversion element 101 is brought into conduction when the thermoelectric conversion elements 101 come into contact with each other and the power generation capability of the thermoelectric conversion module 100 is reduced. Is preferable.

  Next, as shown in FIG. 3A, a plurality of thermoelectric conversion elements 101 are alternately arranged in a P-type and an N-type using a jig 301 for arranging the thermoelectric conversion elements 101. After the arrangement in one row, as shown in FIG. 3B, the spacers 104 are arranged on the plurality of arranged thermoelectric conversion elements 101 and in the recesses formed by the two thermoelectric conversion elements 101. Further, when an insulator whose surface is coated with an adhesive is used as the spacer 104, the spacer is applied after the adhesive is applied to the insulator before the arrangement.

  Then, as shown in FIG. 3C, these are repeated until the number of thermoelectric conversion elements 101 required as the thermoelectric conversion module 100 is reached. Thereafter, the arranged thermoelectric conversion elements 101 and the spacers 104 are bonded by heating or the like.

  In this embodiment, heating is used as a method for curing the adhesive between the thermoelectric conversion element 101 and the spacer 104. However, pressure reduction, standing at room temperature, ultraviolet curing, or a combination of these methods may be used. In this embodiment mode, the insulator 106 whose surface is coated with the adhesive 105 is used as the spacer 104; however, the spacer 104 itself may be formed of an adhesive or a resin. Thereby, the process of coating the adhesive 105 on the surface of the insulator 106 can be omitted.

  Thereafter, as shown in FIG. 3D, the jig 301 is removed, and the block 302 to which the thermoelectric conversion element 101 and the spacer 104 are bonded is cut (sliced) to a desired thickness. Thereafter, wiring is formed so that the P-type and N-type thermoelectric conversion elements 101 are sequentially connected in series (not shown). As a method for forming the wiring, a method of soldering a conductive material, thermal spraying, a method of soldering an insulating substrate formed with wiring, or the like can be used. Cu, Ni, Al, and alloys containing these can be used as the conductive material and the thermal spray material.

  The presence of the spacer 104 maintains the shape of the thermoelectric conversion module 100 and improves the strength, so that the thermoelectric conversion module 100 without an insulating substrate can be formed. In an ordinary thermoelectric conversion module, an expensive alumina substrate is used as an insulating substrate. Therefore, the cost can be greatly reduced by not using the insulating substrate.

  In the present embodiment, the case where the number of thermoelectric conversion elements 101 adjacent to one spacer 104 is four has been described, but three may be used.

  In the case of four, as shown in FIG. 3, when arranging a plurality of thermoelectric conversion elements 101, the arrangement is lost without the spacers 104, so that the operation of arranging the thermoelectric conversion elements 101 by the spacers 104 is simplified. Become. On the other hand, in the case of three, since the number of thermoelectric conversion elements 101 per unit area increases, high output can be obtained with the same size of the thermoelectric conversion module 100.

  As described above, according to the present invention, it is possible to obtain a thermoelectric conversion module having a low module price per power generation amount, a high strength, and a high long-term reliability, and a manufacturing method thereof. Therefore, the present invention can be widely applied in various technical fields when temperature control or power generation from heat is required.

DESCRIPTION OF SYMBOLS 100 Thermoelectric conversion module 101 Thermoelectric conversion element 102 Insulator 103 Thermoelectric conversion material 104 Spacer 105 Adhesive 106 Insulator 301 Jig 302 Block 401 Insulating substrate 402 Element fitting hole 403 Element through-hole 404 Support sheet 405 Electrode

Claims (9)

In a thermoelectric conversion module composed of a plurality of P-type thermoelectric conversion elements and a plurality of N-type thermoelectric conversion elements that are alternately arranged and electrically connected in series,
Arranging spacer members in a space surrounded by a plurality of thermoelectric conversion elements,
A thermoelectric conversion module. The thermoelectric conversion module according to claim 1, wherein a space surrounded by the plurality of thermoelectric conversion elements is filled with an adhesive. The thermoelectric conversion module according to claim 1, wherein the spacer member is made of an insulator. The thermoelectric conversion module according to claim 3, wherein the insulator is rod-shaped glass. The thermoelectric conversion module as described in any one of Claims 1-4 which has a space | gap part between two adjacent thermoelectric conversion elements and a spacer member. The thermoelectric conversion module according to claim 1, wherein the spacer member has a cylindrical shape. The thermoelectric conversion module according to claim 1, wherein the number of thermoelectric conversion elements adjacent to one spacer member is four. The thermoelectric conversion module according to any one of claims 1 to 6, wherein the number of thermoelectric conversion elements adjacent to one spacer member is three. A first step of preparing a jig for arranging the thermoelectric conversion elements, and alternately arranging P-type and N-type thermoelectric conversion elements inside the jig;
A second step of arranging a spacer member in a recess formed by the plurality of thermoelectric conversion elements;
A third step of applying an adhesive to the surface of the spacer member;
A fourth step of repeating the second and third steps until the predetermined number of arrangements, and then curing the adhesive to form a block;
Slicing the block and forming a wiring so that the P-type and N-type thermoelectric conversion elements are sequentially connected in series.
The manufacturing method of the thermoelectric conversion module characterized by these.

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