WO2011157333A2

WO2011157333A2 - Electrothermal conversion

Info

Publication number: WO2011157333A2
Application number: PCT/EP2011/002399
Authority: WO
Inventors: Helmut Walter; Christof Böttcher
Original assignee: Volkswagen Aktiengesellschaft
Priority date: 2010-06-19
Filing date: 2011-05-14
Publication date: 2011-12-22
Also published as: WO2011157333A3; DE102010024414A8; DE102010024414A1

Abstract

The invention relates to a method for producing an electrothermal converter (1) by means of which a heat flow can be generated, with the supply of electrical energy, to counter a temperature drop, or vice versa. In order to allow improved electrothermal conversion, the following production processes are provided - integration of at least two pellets, which differ in respect of an electrothermal material (13), in a carrier (19), - application of one or a large number of electrical contacts (11) to the at least two pellets for electrical connection of the at least two pellets, - application of an electrical insulation means (9) at least to the electrical contacts (11) for electrically insulating the contacts (11).

Description

description

Electrothermal conversion

The invention relates to a method for producing an electrothermal converter by means of which a heat flow under supply of electrical energy against a temperature gradient can be generated, or vice versa, a method according to the invention

electrothermal converter, a heat exchanger equipped with the converter, and a motor vehicle equipped with the heat exchanger.

Electrothermal transducers are used to generate a heat flow against a temperature gradient under the supply of energy or in the reverse case for the production of electrical energy. Such electrothermal transducers are also under the

Designation Peltier element known, which use a so-called Peltier effect to convert the electrical energy into the heat flow or vice versa.

Electrothermal transducers have at least two different electrothermal materials, such as semiconductors, for example n-doped and p-doped semiconductors, which are alternately contacted with one another. Transitions from one electrothermal material to the other material take place on a first side of the electrothermal transducer, and transitions in a correspondingly reverse direction take place on another side of the electrothermal transducer, with electrons forming the current flow each changing their energy level on one of the sides in the same direction in which heat is released on one side of the electrothermal transducer and heat is removed on the other side of the electrothermal transducer. Furthermore, it is known to use electrothermal transducers in heat exchangers, for example liquid-to-liquid heat exchangers, wherein the heat flow is transported by a first fluid flow by means of the electrothermal transducer under the supply of electrical energy in the second fluid stream. EP 1 366 328 B1 relates to an electrothermal system for use with at least one medium to be cooled or heated. The system comprises a plurality of electrothermal elements made of p-doped and n-doped semiconductors, wherein an element-to-element electrical connection is made via circuits, so that an electrothermal grouping is formed with a cooling side and a heating side, with several electrothermic elements in at least one direction over the grouping are thermally insulated from each other. The system further comprises at least one heat exchanger at least on the cooling or heating side in thermal communication with at least one electrothermal element, the heat exchanger being configured to to sustainably maintain thermal insulation of the eutothermic elements, wherein the at least one heat exchanger comprises a plurality of sections, each section being in thermal communication with at least one electrothermic element, at least some of the sections being substantially thermally insulated from other sections in the direction of medium movement. EP 1 384 271 B1 relates to a cooling device which has a housing with at least one cooling channel for a cooling liquid and with at least one eiektrothermischen cooling element, which is a layer of

Semiconductor material, wherein at least one of the plates has an electrically insulating contact surface which is in use in direct contact with the cooling liquid, wherein the at least one cooling element is flexibly and sealingly formed along its outer periphery in a carrier, that the contact surface further the cooling liquid unobstructed, wherein the carrier and the contact surface define a wall portion of the cooling channel, wherein the housing has two cooling channels and wherein the at least one framed in the support cooling element opposite contact surfaces on both plates of the

Cooling element, wherein the carrier and the framed cooling elements form in this way a partition wall in the cooling channels.

The object of the invention is to enable an improved electrothermal conversion, in particular to provide an improved method for producing an eiektrothermischen transducer, in particular to enable a precisely constructed eiektrothermischen converter.

The object is achieved in a method for producing a eiektrothermischen converter by means of which a heat flow under supply of electrical energy against a temperature gradient can be generated, or vice versa. They include integrating at least two pellets differing in an electrothermic material in a carrier, applying one or a plurality of electrical contacts to the at least two pellets for electrically connecting the at least two pellets and applying an electrical insulation, in particular insulating layer, provided at least on the electrical contacts for electrically insulating the contacts. Advantageously, the at least two different pellets can be integrated in the carrier.

Advantageously, these can thereby be prefixed and / or better aligned relative to each other. This advantageously simplifies the step of electrical contacting by means of the electrical contacts which are applied to the at least two pellets. Subsequently, the electrical insulating layer can be applied at least to the electrical contacts. The electrical insulation, in particular an insulating layer, is advantageously constructed so that it allows a high heat transfer, but is insulating for electrical power. The carrier is advantageously constructed so that this is electrically and thermally insulating, so that the different pellets are both electrically and best possible thermally insulated with each other. Both

Electro-thermal materials may be n-doped and p-doped

Semiconductor material act, wherein the at least two pellets adjacent to each other are integrated into the carrier. In a more complex form, a plurality of the respective two adjacent pellets are integrated into the carrier, wherein these are alternately contacted on a hot side and on a cold side of the eiektrothermischen transducer. This principle is known in so-called Peltier elements, so that will not be discussed further here.

In one embodiment of the method, a pairwise covering of the at least two pellets with the electrical contacts is provided. The electrical contacts can advantageously be metal platelets and / or a conductive foil, wherein the electrical contacts preferably also have good thermal conductivity, such as aluminum or copper, in addition to good electrical conductivity. Advantageously, the at least two pellets which form a pair can be covered by one of the electrical contacts, so that initially only the electrical contacts that are covered by the insulating layer are present or visible on both the hot side and the cold side of the electrothermal converter are. Advantageously, in addition to a good electrical contact, a good heat conduction can be ensured.

In a further embodiment of the method, application of the electrical insulating layer to a cold side and a hot side of the electrothermal transducer is provided in each case over at least the electrical contacts and / or a surface of the carrier remaining between the pellets and / or electrical contacts.

Advantageously, the surface of the carrier, the pellets and / or the electrical contacts can be completely coated with the insulating layer. Advantageously protects the

Insulating the hot side and the cold side of eiektrothermischen transducer from damage and / or short circuits, but a good heat conduction is guaranteed.

In a further embodiment of the method, the at least two pellets are integrated by means of encapsulation and / or encapsulation with a thermally and electrically insulating material. Advantageously, the pellets can first be placed in a tool, in particular injection mold and then encapsulated in a simple manner with the carrier. Advantageously, the pellets can be positioned precisely and form a stable assembly with the carrier after encapsulation. This stable assembly can be advantageously provided for contacting with the electrical contacts.

In a further embodiment of the method, a production of the carrier as a preform having breakthroughs and an introduction of the at least two pellets into the openings of the carrier are provided. The pellets can be introduced in any way in the openings, for example by means of gluing, bonding, positive, frictional, in particular by pressing to produce a

Press fit and / or the like. Advantageously, the preform can be positioned exactly

Have breakthroughs, so that after the introduction of the pellets are accurately positioned and / or fixed within the carrier.

In a further embodiment of the method, an introduction of the two pellets into the apertures by means of pressing in and / or by means of gluing are provided. Advantageously, the assembly can be done in a simple manner with the pressing and / or gluing. In this case, a secure fixation of the pellets is guaranteed in the breakthroughs.

The object is also an electrothermal transducer by means of a

Heat flow under supply of electrical energy against a temperature gradient can be generated, or vice versa, solved. The electrothermal transducer has at least two different pellets containing electrothermal materials, a carrier in which the at least two pellets are integrated, a plurality of electrical contacts by means of which the at least two pellets are electrically contacted and an electrical insulating layer which is at least on the plurality of electrical Contacts is applied and by means of which the electrical contacts are electrically isolated. Advantageously, the result of the carrier is a good thermal insulation, good electrical insulation and / or good

Positioning the pellets relative to each other. In addition, results in a total against mechanical damage, vibrations, thermal stresses and / or other environmental influences, such as liquids, acids and / or the like very well protected electrothermal transducer. Preferably, the electrothermal transducer can be produced by a method described above. In this respect, the advantages described above arise.

In one embodiment, it is provided that the pellets each have two plane-parallel surfaces which are surrounded by the surface of the carrier. Advantageously, the pellets on the hot side and on the cold side are each contacted in a plane and are covered by the insulating layer. In a further embodiment of the electrothermal transducer is provided that the surface of the carrier and the plane-parallel surfaces of the at least two pellets on the hot side and on the cold side are each in a common plane.

Advantageously, a partial assembly of the electrothermal transducer comprising the carrier and the at least two pellets on the hot side and on the cold side on a generally flat surface. Advantageously, this overall flat surface, which is formed on the pellets and the carrier, are provided in a simple manner with the electrical contacts. This can be done for example by gluing with an electrically conductive adhesive, by soldering and / or by any other electrical contact-making method, such as welding and / or the like.

The object is also achieved in a heat exchanger with a previously described electrothermal transducer. This results in the advantages described above.

The object is further in a motor vehicle with a previously described

Heat exchanger dissolved. Advantageously, the equipped with the electrothermal transducer heat exchanger can serve as a chiller and / or heat engine, without any moving parts. gets along and thus works largely wear-free. Advantageously, the heat and / or the cold can be transported to an arbitrary location of the motor vehicle by means of fluid passages guided through the heat exchanger, for example into an interior space, into seats inside the interior, to one

Drive source and / or other to be tempered units, such as power electronics and / or the like.

Further advantages, features and details will become apparent from the following description in which - where appropriate, with reference to the drawings - at least one embodiment is described in detail. Described and / or illustrated features form the subject of the invention, or independently of the claims, either alone or in any meaningful combination, and in particular may additionally be the subject of one or more separate applications. The same, similar and / or functionally identical parts are provided with the same reference numerals. Show it: 1 shows an electrothermal transducer according to the prior art;

Figures 2-4 three-dimensional schematic views, partially in

Exploded view to illustrate a preparation of an electrothermal transducer according to the invention with a carrier;

FIG. 5 shows a heat exchanger with an electrothermal converter; and Figure 6 shows another heat exchanger with a total of three electrothermal

Converters.

Figure 1 shows an electrothermal transducer 1 according to the prior art. The converter 1 has a cold side 3 and a hot side 5. For connection to a DC voltage source, not shown, the converter 1 has an electrical connection 7. In an applied DC voltage, the cold side 3 acts as a heat sink and the

Warm side 5 as a heat source, wherein a reversal of the applied voltage causes the cold side 3 acts as a heat source and the hot side 5 as a heat sink. Furthermore, the converter 1 can be operated and / or designed as an electrothermal generator, wherein application of a temperature difference between the cold side 3 and the hot side 5 induces a voltage at the electrical connection 7.

The cold side 3 and the hot side 5 each have an insulation 9, for example, a ceramic substrate. Between the insulation 9, a plurality of electrical contacts 11 are arranged, which are formed as rectangular platelets, for example as a metal plate. The electrical contacts 11 each contact a pair of two electrothermal materials 13 existing pellets, such as a p-type semiconductor 15 and an n-type semiconductor 17. The semiconductors 15, 17 of the electrothermal material 13 are connected by means of the electrical contacts 11 so that on Cold side 3 is always a transition from the p-type semiconductor 15 via the electrical contact 11 to the n-type semiconductor 17 and reversed on the hot side always a transition from the n-type semiconductor 17 to the p-type semiconductor 15. Between the semiconductors 15, 17th remains an electrically insulating airspace.

FIGS. 2 to 4 show individual components and assemblies of an electrothermal transducer 1 according to the invention, partially in an exploded view to illustrate a method for producing the electrothermal transducer 1. This method will be explained in more detail below with reference to FIGS

Differences from the illustration according to FIG. 1 will be discussed. In FIG. 2 it can be seen that the semiconductors 15 and 17 are integrated in a carrier 19. The carrier 19 can be manufactured as a preform in an upstream production or manufacturing process. The carrier 19 has openings 21, which are adapted in an inner contour to an outer contour of the semiconductor 15,17. As illustrated in FIG. 2, the semiconductors 15, 17 are integrated into the carrier 19, for example, which is symbolized by arrows in FIG. 2, this can be done, for example, by pressing in and / or gluing.

It can be seen that the semiconductors 15, 17 of the electrothermal material 13 have at least two flat surfaces, one of the surfaces facing towards the cold side 3 and another towards the hot side 5. The semiconductors 15, 17 are therefore designed as two-ply pellets, wherein a two-flattened one can be understood to be any external shape which has at least two planar surfaces. In the present case, the semiconductors 15, 17, as can be seen in FIG. 2, are of cuboid design. Instead of the parallelepiped configuration of the semiconductors 15, 17, any other shape, for example hexagonal, round or the like may be provided. Preferably, the two faces of the semiconductors 15, 17 facing the cold side 3 and the hot side 5 are rectangular, as shown in FIG.

The two surfaces of the semiconductors 15, 17 are plane-parallel and terminate flush with a surface 23 of the carrier 19. Thus, both on the cold side 3 and on the hot side 5 there is a uniform surface which is composed of the surface 23 of the carrier 19 and the surfaces 25 of the semiconductors 15, 17.

As can be seen in FIG. 3, the partial assembly of the carrier 19 and the semiconductors 15, 17 is equipped with the electrical contacts 11, so that the electrical contacting of the semiconductors 15, 17 of the electrothermal material described in FIG. The electrical contacts 1 1, for example, as a thin

Conductor tracks be configured and are also rectangular according to the shape of the semiconductor 15,17.

Figure 4 shows a partial assembly of the transducer 1 with the electrical contacts 11, the semiconductors 15,17 of the electrothermal material 13 and the support 19. It can be seen that the electrical contacts 11 in pairs a p-type semiconductor 15 and an n-type semiconductor Cover completely 17, so that the cold side 3 and the hot side 5, the surface 23 of the support 19, as far as it is not covered by the electrical contacts 11 and the electrical contacts 11 remain even. In a further manufacturing process, not shown, the insulation 9, for example a thin insulating layer, is applied to the partial assembly of the transducer 1 shown in FIG. This can be done, for example, in the form of a glued-on foil, a heat-shrinkable tube and / or a plate, for example consisting of a ceramic substrate, as shown in FIG.

FIG. 5 shows a partially illustrated motor vehicle 27 with an electrothermal heat exchanger 29. The heat exchanger 29, as shown in FIG. 5, has a gap 31, into which an electrothermal transducer 1 according to FIGS. 2 to 4 is introduced. Along the cold side 3 of the converter 1, a first fluid path 33 is arranged. Along the hot side 5 of the converter 1, a second fluid path 35 is arranged. 5, flow directions of fluid flows guided through the fluid paths 33, 35, for example a liquid or a gas, are symbolized by means of arrows 37. The heat exchanger 29 according to FIG. 5 can be operated as an electrothermal countercurrent liquid-liquid heat exchanger 29. Advantageously, by means of the fluid flows a not-shown components of the motor vehicle 27 can be tempered, for example, cooled or warmed. The component may be, for example, a component of a drive source, an electric motor, power electronics, an interior, a component of the interior, a seat, an armrest and / or the like.

FIG. 6 shows a further heat exchanger 29 of another motor vehicle 27 shown only in part. In contrast to the representation according to FIG. 5, FIG

Heat exchanger 29 according to Figure 6 a total of three gaps 31, in which a total of three of the electrothermal transducers 1 are introduced. In contrast to the representation of FIG. 5, according to FIG. 6, the fluid paths 33 and 35 are in each case deflected in a U-shaped manner at an angle of 180 ° and meshed with one another. It can be seen that in each case an outer section of the fluid paths 33, 35 with a cold side 3 or a warm side 5 of one of the transducers 1 is in a heat-transmitting abutment contact within the gap 31. The interlocked inner portions of the fluid paths 33 and 35 are each on both sides with two cold sides 3 and two hot sides 5 of the corresponding transducer 1 in a heat-transferring contact, so are both sides warmed or cooled.

Advantageously, as shown in Figures 2 to 4, the transducer 1 can be optimally prepared, with an improvement of electrical and thermal insulation and / or avoidance of corrosion can be achieved by condensation occurring on the cold side 3. Advantageously, the semiconductors 15, 17, which are designed, for example, as two-layer pellets, can be integrated into the carrier 19. Alternatively and / or additionally this, not as shown in Figure 2 by pressing, also by overmolding with a both thermally and electrically insulating material, such as a plastic or a ceramic happen. As shown in FIG. 2, pressing and / or bonding of the semiconductors 15, 17 into the preform of the carrier 19 takes place.

In a subsequent manufacturing process, as shown in Figure 3, the

electrical contacts 1 1, which are designed in particular as conductor tracks, applied to the preform or the carrier 19 and electrically contacted with the semiconductors 15,17. The electrical contacts 1 1, which are designed in particular as conductor tracks, for example, copper, aluminum or other materials having a good electrical conductivity, and in particular a good thermal conductivity, have. Alternatively and / or additionally, the electrical contacts 11 may comprise materials with added nanotubes.

The application of the electrical contacts 11, in particular the conductor tracks, can be done by printing, soldering, gluing with an electrically conductive adhesive and / or in any other way. The cold side 3 and the warm side 5 can be provided individually with the electrical contacts 1 or alternatively together with the contacts 1 1.

In order to avoid a possibly occurring short circuit at the electrical contacts 11 or the printed conductors, they can be advantageously protected by the electrically insulating, but thermally highly conductive layer, such as in Figure 1 as insulation 9, protected. Advantageously, the preassembled transducer 1, as shown in Figure 4, molded, painted, provided with a shrink tube, with a glued foil and / or a plate.

The electrothermal transducers 1 which can be produced according to FIGS. 2 to 4 can in particular be provided with a thermal compound in the gap 31 of one of the prefabricated heat exchangers 29. Compared to conventional heat exchangers or liquid-liquid heat exchangers, it is not the fluid paths 33, 35 or the fluid streams guided therein that are guided past one another as much as possible

Temperature compensation to achieve. Rather, as shown in Figure 5, between the fluid paths 33 and 35 a, or as shown in Figure 6, a plurality of the electrothermal transducers 1 in the or the columns 31 are arranged. The heat exchanger 29 shown in Figures 5 and 6 may be part of two liquid-conducting circuits of the motor vehicle 27, in which the gap 31 is present between the circuits. In this gap 31 of the electrothermal transducer 1 is inserted. For thermal connection between the transducer 1 and the fluid paths 33,35 of the heat exchanger 29 may in particular a Thermal grease can be used. Advantageously, the gap 31 is designed such that a bias voltage to the converter or 1 is formed. As a result, the converter 1 has a good thermal connection to the fluid circuits of the fluid paths 33, 35. In a multi-stage heat exchanger 29, as shown in Figure S, advantageously more of the electrothermal transducer 1 can be arranged so that advantageously the circuits of the fluid paths 33,35 are traversed in an opposite direction.

LIST OF REFERENCE NUMBERS

converter

cold side

warm side

electrical connection

insulation

electrical contacts

materials

p-type semiconductor

n-type semiconductor

carrier

breakthroughs

surface

surfaces

motor vehicle

heat exchangers

gap

fluid path

arrows

Claims

claims

Method for producing an electrothermal converter (1) by means of a heat flow under the supply of electrical energy against a

Temperature gradient can be generated or vice versa, with:

Integrating at least two pellets differing with respect to an electrothermal material (13) in a carrier (19),

Applying one or a plurality of electrical contacts (11) to the at least two pellets for electrically connecting the at least two pellets,

Applying an electrical insulation (9) at least to the electrical contacts (11) for electrically insulating the contacts (11).

Method according to the preceding claim, comprising: pairwise overlapping the at least two pellets with the electrical contacts (11).

Method according to one of the preceding claims, comprising:

Applying the electrical insulation (9), in particular an insulating layer, to a cold side (3) and a hot side (5) of the electrothermal transducer (1), in each case over the electrical contacts (11) and one between the pellets and / or electrical contacts (11) remaining surface (23) of the carrier (19).

Method according to one of the preceding claims, comprising:

Integrating the at least two pellets by means of encapsulation and / or encapsulation with a thermally and electrically insulating material.

5. The method according to any one of the preceding claims 1 to 3, with:

Producing the carrier (19) as a preform having apertures (21), integrating the at least two two-fold means by introducing the at least two pellets into the apertures (21) of the carrier (19).

A method according to the preceding claim, comprising at least one of the following:

Introducing the at least two Rellets in the openings (21) by means of pressing,

Introducing the at least two pellets into the apertures (21) by means of gluing

Application of electrical contacts (11) by printing, gluing with an electrically conductive adhesive, soldering and / or welding

Applying the insulation (9) as an insulating layer, in particular in the form of a glued foil, a shrink tube and / or a plate.

7. Electrothermal transducer (1) by means of which a heat flow under supply of electrical energy against a temperature gradient is generated or vice versa, comprising: at least two, with respect to an electrothermal material (13) different pellets, a support (19) in which the at least two pellets are integrated, one or a plurality of electrical contacts (11) by means of which the at least two pellets are electrically contacted, an electrical insulation (9) which is applied to at least one or the plurality of electrical contacts (11) and by means of the electrical contacts (1) are electrically insulated.

8. An electrothermal transducer according to the preceding claim, wherein the pellets each have two plane-parallel surfaces (25) which are surrounded by the surface (23) of the carrier (19).

9. The electrothermal transducer according to one of the preceding two claims, wherein the surface (23) of the carrier (19) and the plane-parallel surfaces (25) of the at least two pellets on the hot side (5) and on the cold side (3) each in a common Lie flat.

10. An electrothermal transducer according to one of the preceding three claims,

producible according to one of the preceding three claims.

11. Heat exchanger (29) with an electrothermal transducer (1) according to one of the preceding four claims.

12. Motor vehicle (27) with a heat exchanger (29) after the preceding

Claim.