Cooling device for cooling an energy accumulator and/or electronic assembly and method of manufacturing the same

Abstract

The invention relates to a cooling device for cooling an energy accumulator and/or electronic assembly, comprising a preferably plate-shaped heat sink in whose interior at least one coolant channel is formed, wherein the heat sink comprises two sheet metal blanks cohesively joined onto each other surface to surface, wherein one sheet metal blank has a channel-shaped bulge that bulges out of the joining plane of the two sheet metal blanks with about the same wall thickness, is connected to the other sheet metal blank only at its edge, and forms the coolant channel.

Claims

1. A cooling device for cooling an energy accumulator and/or electronic assembly, the cooling device comprising: a plate-shaped heat sink in whose interior at least one coolant channel is formed, wherein the plate-shaped heat sink comprises a first sheet metal blank and a second sheet metal blank, wherein the first sheet metal blank and the second sheet metal blank are adhesively joined to each other surface to surface, wherein the first sheet metal blank has a channel-shaped bulge that bulges out of the joining plane between the first sheet metal blank and the second sheet metal blank with about the same wall thickness, is connected to the second sheet metal blank only at its edge, and forms the at least one coolant channel.

2. The cooling device of claim 1, wherein the first sheet metal blank and the second sheet metal blank are adhesively joined to each other surface to surface with a roll-bonding joining connection.

3. The cooling device of claim 1, wherein the channel-shaped bulge has a harmoniously curved wave contour as seen in cross-section.

4. The cooling device of claim 1, wherein the channel-shaped bulge is formed by inflation.

5. The cooling device of claim 1, wherein only the first sheet metal blank has the channel-shaped bulge, and wherein the second sheet metal blank is flat and/or has a bulge-free surface.

6. The cooling device of claim 1, wherein the adhesively joined first sheet metal blank and the second sheet metal blank form a flat heat sink plate with the exception of the channel-shaped bulge.

7. The cooling device of claim 1, wherein the first sheet metal blank and the second sheet metal blank have substantially the same wall thickness and the joining plane or surface between the first sheet metal blank and the second sheet metal blank extends approximately centrally through a cross-sectional area of the plate-shaped heat sink.

8. The cooling device of claim 1, wherein the first sheet metal blank and the second sheet metal blank are aluminum sheets.

9. The cooling device of claim 1, wherein the plate-shaped heat sink comprises a first plate-shaped heat sink, wherein the cooling device further comprises a second plate-shaped heat sink comprising at least one coolant channel and sheet metal blanks joined to each other, wherein the first plate-shaped heat sink and the second plate-shaped heat sink are arranged at a distance from each other and by traction elements are held against each other and on the energy accumulator and/or electronic assembly so that a gap between the first plate-shaped heat sink and the second plate-shaped heat sink corresponds to dimensions of the energy accumulator and/or electronic assembly, and wherein the energy accumulator and/or electronic assembly is clamped between the first plate-shaped heat sink and the second plate-shaped heat sink.

10. The cooling device of claim 9, wherein on surfaces facing apart from each other holders are seated on the first plate-shaped heat sink and the second plate-shaped heat sink, and wherein the holders are held by the traction elements.

11. The cooling device of claim 10, wherein the holders are of plate-shaped design, and wherein the traction elements are latchable to the holders.

12. The cooling device of claim 1, wherein the plate-shaped heat sink comprises connection surfaces shaped-adapted to connection poles of the energy accumulator and/or electronic assembly, and wherein the connection surfaces comprise bore- and/or hole-like recesses shape-adapted to pin-like protruding connection journals of a battery and/or a capacitor.

13. The cooling device of claim 1, wherein the first sheet metal blank and the second sheet metal blank have an aluminum oxide (Al.sub.2O.sub.3) coating.

14. An energy accumulator and/or electronic assembly comprising the cooling device of claim 1 for cooling at least one energy accumulator and/or electronic module.

15. The energy accumulator and/or electronic assembly of claim 14, wherein the at least one energy accumulator and/or electronic module is clamped between two heat sinks comprising the plate-shaped heat sink and another heat sink, and wherein the two heat sinks are held against each other by traction elements and are held on the at least one energy accumulator and/or electronic module.

16. The energy accumulator and/or electronic assembly of claim 15, wherein at least one of the two heat sinks is in contact with a connection pole of the at least one energy accumulator and/or electronic module.

17. The energy accumulator and/or electronic assembly of claim 15, wherein two holders separate from the two heat sinks are seated on sides of the two heat sinks facing away from the at least one energy accumulator and/or electronic module and are held on the at least one energy accumulator and/or electronic module by the traction elements.

18. The energy accumulator and/or electronic assembly of claim 15, wherein the traction elements are pull rods.

19. The energy accumulator and/or electronic assembly of claim 15, wherein at least one of the traction elements is latchable in place on at least one of the two heat sinks.

20. The energy accumulator and/or electronic assembly of claim 14, wherein the at least one energy accumulator and/or electronic module comprises a plurality of energy accumulator and/or electronic modules arranged adjacent to each other in a row or in a matrix and are clamped by two common heat sinks on opposite sides.

21. The energy accumulator and/or electronic assembly of claim 14, wherein the at least one energy accumulator and/or electronic module comprises at least one connection pole, wherein the plate-shaped heat sink comprises a connection surface shaped-adapted to the at least one connection pole, and wherein the plate-shaped heat sink comprises an insulating and/or thermally conductive coating comprising a ceramic coating or an aluminum oxide coating.

22. A method of manufacturing a cooling device for cooling an energy accumulator and/or electronic assembly comprising at least one plate-shaped heat sink having at least one coolant channel, wherein the at least one plate-shaped heat sink comprises two sheet metal blanks that are cohesively joined to each other surface to surface by roll bonding, wherein before the two sheet metal blanks are cohesively joined to each other surface to surface by roll bonding, a release agent is provided on at least one of the two sheet metal blanks corresponding to the course of the at least one coolant channel, and wherein after the two sheet metal blanks are cohesively joined to each other surface to surface by roll bonding, at least one of the two sheet metal blanks is bulged by shaping in the region of the release agent in order to form the at least one coolant channel.

23. The method of claim 22, wherein the at least one of the two sheet metal blanks is bulged for forming the at least one coolant channel by inflation and/or by introduction of a pressurized fluid into a joining point between the two sheet metal blanks in the region of the release agent.

24. The method of claim 22, wherein before the two sheet metal blanks are cohesively joined to each other surface to surface by roll bonding, the release agent is printed on a surface of at least one of the two sheet metal blanks by a screen printing process.

25. The method of claim 22, wherein only one of the two sheet metal blanks is bulged for forming the at least one coolant channel.

26. The method of claim 22, wherein an insulating and/or thermally conductive coating is applied onto the at least one plate-shaped heat sink after the two sheet metal blanks are cohesively joined to each other surface to surface by roll bonding.

27. The method of claim 22, wherein on the at least one plate-shaped heat sink a plate-shaped holder is applied which is held by at least one traction element.

28. The method of claim 22, wherein on at least one of the two sheet metal blanks and/or on the at least one plate-shaped heat sink an insulating and/or thermally conductive coating is applied.

29. The method of claim 28, wherein an aluminum oxide coating is applied by plasma coating.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The invention will be explained in detail below with reference to a preferred exemplary embodiment and associated drawings. In the drawings:

[0035] FIG. 1: shows a side view of an energy accumulator assembly, which in a sandwich-like manner is arranged between two plate-shaped heat sinks that are clamped onto the energy accumulator assembly by pull rods,

[0036] FIG. 2: shows a top view of one of the plate-shaped heat sinks, which illustrates the course of the coolant channel in the interior of the heat sink, and

[0037] FIG. 3: shows a schematic representation of the method steps for manufacturing the plate-shaped heat sinks from the preceding Figures.

DETAILED DESCRIPTION

[0038] As is shown in FIGS. 1 and 2, the cooling device 6 can be configured to cool a row or matrix of energy accumulators 1 or similar electronic, in particular power-electronic components at their connection poles 7, wherein it would also be possible, however, to only cool an individual energy accumulator or electronic component 1 by means of the cooling device 6.

[0039] As is shown in FIGS. 1 and 2, the cooling device 6 can include two plate-shaped heat sinks 3 which are attached to said arrangement of energy accumulators 1 from opposite sides in order to contact their connection poles 7 and provide for a heat transfer from the connection poles 7 to the heat sink 3.

[0040] Advantageously, the energy accumulators 1 can be arranged or clamped between the two plate-shaped heat sinks 3 in a sandwich-like manner. The two heat sinks 3 can be spaced apart from each other or be held against each other by means of traction elements 4 for example in the form of pull rods, wherein the traction elements 4 in particular can hold the heat sinks 3 together on the opposite sides of the energy accumulators 1.

[0041] To hold the heat sinks 3 against the energy accumulators 1, holders 5, which can be configured as holding plates or holding frames, can be placed on the sides of the heat sinks 3 facing away from the energy accumulators 1, wherein said holders 5 are held together by means of the traction elements 4, in particular in such a way that the holders 5 hold the heat sinks 3 against the front sides or outer sides of the energy accumulators 1.

[0042] Advantageously, said traction elements 4 can be positively connected, advantageously be latched to the holders 5, wherein however other connecting means such as screws or bayonet locks or the like can also be provided.

[0043] Said holders 5 can be configured for example in the form of inexpensive steel sheets which are placed on the heat sinks 3, wherein however other types of holders 5, for example in the form of a strut framework, can also be used.

[0044] As is shown in FIG. 2, the plate-shaped heat sinks 3 can comprise one or more coolant channels 8 in their interior, wherein for example a meandrous coolant channel winding back and forth can be provided, which guides the coolant over all connecting surfaces or external poles 7 of the energy accumulators 1 connected therewith. Instead of the meandrous coolant channel 8 shown in FIG. 2, however, other coolant channel patterns can also be provided, which can include a plurality of separate and/or branching coolant channels.

[0045] Corresponding to the arrangement of the energy accumulators 1 and their connection poles 7, the respective heat sink 3 can have a corresponding arrangement of contact surfaces 9 which contact the energy accumulators 1 at their connection poles 7 and can be formed on a surface, in particular on a flat side of the plate-side heat sink 3.

[0046] Said two heat sinks 3 advantageously each are constructed from two sheet metal blanks 10, 11 which over a full or large surface are cohesively connected to each other in order to form the heat sink 3. Said sheet metal blanks 10 and 11 advantageously can be aluminum sheets of preferably small wall thickness, i.e. the material thickness is only a fraction of the length and/or the width of the corresponding sheet metal blank 10, 11, for example less than 10% or less than 5% of the length and/or the width.

[0047] Possibly, more than two sheet metal blanks can also be joined onto each other, in order to form for example a three-layer or multilayer heat sink 3 and/or manufacture a heat sink 3 with a coolant channel pattern in different layers.

[0048] As is illustrated in FIG. 3, the sheet metal blanks 10 and 11 can be cohesively joined together by a roll-bonding process, wherein the sheet metal blanks 10 and 11 can be placed one on top of the other with their large flat sides and can pass through a roller assembly 12. In particular, rotating rollers can be used to apply high pressure and, if necessary, temperature to the sheet metal blanks 10 and 11 lying one on top of the other in order to cohesively connect the sheet metal blanks 10 and 11 at the surfaces adjoining each other. The two sheet metal blanks 10 and 11 connected to each other can jointly have a material thickness or heat sink thickness which can be reduced as compared to the sum of the thicknesses of the initial sheet metal blanks, cf. FIG. 3.

[0049] As is illustrated in FIG. 3, the two sheet metal blanks 10 and 11 for example can be cut from an aluminum sheet in order to then be placed one on top of the other. To promote or support the roll-bonding joining process, the blank surfaces to be placed one on top of the other can be machined, for example be brushed or prepared in some other way.

[0050] To provide for the formation of the coolant channels 8 in a future manufacturing step, a release agent 13 for example in the form of a graphite-containing paint can be applied onto at least one sheet metal blank 10 corresponding to the course of the desired coolant channel, wherein said release agent 13 can be applied for example by a screen printing process.

[0051] The release agent 13 is applied onto that surface of the sheet metal blank 10 which is to be joined with the opposite surface of the other sheet metal blank 11, in order to omit portions of the sheet metal blank surfaces adjoining each other, which correspond to the future pattern of the desired coolant channels, from the joining process. Possibly, said release agent 13 can also be applied onto both sheet metal blanks 10 and 11, wherein the release agent 13 need not necessarily be applied on that sheet metal blank which is to be bulged later on by inflation.

[0052] The sheet metal blanks 10 and 11 prepared in this way are then placed one on top of the other and then conveyed through the roller assembly 10, by which they are cohesively connected to each other at high pressure with a possibly additional application of temperature, which in particular in a process of continuous roller pressure can be effected with continuous rotation of the rollers and/or with continuous advance of the sheet metal blank pack relative to the roller assembly 12.

[0053] By pressurizing the rollers, the sheet metal blanks 10 and 11 are cohesively connected to each other surface to surface, namely with the exception of the portions that have been provided with the release agent.

[0054] In a succeeding method step, the sheet metal blanks 10 and 11 cohesively connected to each other surface to surface then are pierced in the region of the coolant channels 8 to be formed, i.e. in the region of the applied release agent pattern, so as to be able to blow in compressed air in the region of the release agent 13 between the sheet metal blanks 10 and 11 in order to inflate the coolant channels 8.

[0055] Advantageously, only one of the sheet metal blanks 10 is bulged out, while the other sheet metal blank 11 can be maintained flat, for example by applying a flat stamping tool against which the connected sheet metal blanks can be urged by a counter-stamp, which can have cutouts in the region of the coolant channels 8 to be formed.

[0056] By inflating the pierced release agent patterns 13, harmoniously curved coolant channels 8 are formed, for example in the form of the meandering coolant channel 8 of FIG. 2, wherein one of the sheet metal blanks 10 bulges out in the form of a groove, wherein said bulge can bulge out of the joining plane.

[0057] To increase the electrical insulation and at the same time achieve a very good thermal conductivity, the sheet metal blanks 10 and 11 and/or the constructed plate-shaped heat sink 3 can be provided with a coating, for example with a ceramic coating for instance in the form of a ceramic paint or a coating with aluminum oxide Al.sub.2O.sub.3. In particular, a plasma coating of one or both sheet metal blanks 10 and 11 and/or of the heat sink 3 constructed therefrom can be provided with an oxide, in particular in the form of said aluminum oxide Al.sub.2O.sub.3. Thereby, a very hard, uniformly flat and mechanically very stable surface can be achieved, which at the same time achieves an excellent electrical insulation with a very good thermal conductivity at the same time.