COOLING MODULE FOR BATTERIES OF AN ELECTRIC OR HYBRID VEHICLE

A cooling module for batteries of an electric or hybrid vehicle that has a coolant supply line, a coolant discharge line, and flat tubes arranged side by side, between which there is space for batteries to be cooled. Each of the flat tubes is connected to the coolant supply line and the coolant discharge line. The flat tubes each carry connectors and the coolant supply line and the coolant discharge line are each assembled from a plurality of line segments connected by a connector of one of the flat tubes to one of the connectors of an adjacent flat tube.

RELATED APPLICATIONS

This application claims priority to EP 23 156 886.6, filed Feb. 15, 2023, and EP 22 202 009.1, filed Oct. 17, 2022, the entire disclosures of both of which are hereby incorporated herein by reference.

BACKGROUND

This disclosure relates to a cooling module for batteries of an electric or hybrid vehicle.

Batteries of electric or hybrid vehicles must be cooled during operation with coolant, usually an aqueous liquid. At low temperatures, the coolant may also be heated and thus used to heat up the batteries.

SUMMARY

This disclosure teaches a cooling module for batteries of electric or hybrid vehicles that is inexpensive to manufacture and can be adapted to the number of batteries, or battery cells, of an electric or hybrid vehicle with little effort.

A cooling module according to this disclosure has a coolant supply line, a coolant discharge line, and a plurality of flat tubes arranged side by side, between which there is space for the batteries that are to be cooled, and which are attached to the coolant supply line and the coolant discharge line. The individual flat tubes can thus, located in parallel with one another, be connected to the coolant supply line and the coolant discharge line, and may run at right angles to the coolant supply line and the coolant discharge line. According to this disclosure, the flat tubes each have connectors, and the coolant supply line and the coolant discharge line are each assembled from a plurality of line segments, each of which connects a connector of one of the flat tubes to a connector of an adjacent flat tube. The line segments may be formed by the connectors or line segments may be separate parts in addition to the connectors.

In this way, the number of flat tubes of a cooling module and thus the number of spaces for the batteries that are to be cooled, can be adapted to vehicle manufacturers' requirements with little effort.

Depending on the shape of the batteries, or battery cells, the flat tubes can be of corrugated or planar design. Corrugated flat tubes are particularly suitable for cylindrical batteries, while flat tubes of planar design are particularly suitable for cuboid batteries, or battery cells. The batteries can, for example, be adhesively bonded onto the flat tubes, or attached to them in some other way. In the case of cuboid shaped batteries flat tubes may be used that touch not only a front side or a back side of batteries, but additionally also part of a lateral side. The flat tubes may be bent correspondingly, for example.

The flat tubes may be made inexpensively of plastic. Another option is to make the flat tubes from metal, for example, from an aluminium alloy, with which an improved thermal coupling of the coolant to the batteries, or battery cells, can be achieved.

Flat tubes made from metal can be produced, for example, as extruded sections, which may be deformed, for example, corrugated, after extrusion.

In an advantageous refinement of this disclosure, provision is made for the connectors to be attached to end pieces, which are attached to ends of the flat tubes. Such end pieces may be attached to the flat tubes, for example, by means of a push-fit connection or a plug-in connection. Alternatively or additionally, a materially bonded connection can be used, for example, in the form of adhesive bonding, soldering, brazing or welding. Connectors may be formed integrally with the end pieces, or may be attached to the end pieces as separate components, for example, by means of a push-fit connection or plug-in connection. Alternatively or additionally, the connectors can also be connected to the relevant end piece by means of a material bond, for example, in the form of adhesive bonding, soldering or welding.

In the cooling module, the flat tubes may run between the coolant supply line and the coolant discharge line. In this case, the flat tubes have an end piece at each of their two ends, with which they are connected by way of connectors to the coolant supply line and the coolant discharge line. Alternatively, the flat tubes may each carry at only one end an end piece with a plurality of connectors. The coolant supply line and the coolant discharge line then run at right angles to the flat tubes on the same side. In this case, each flat tube forms at least two channels running side by side, namely an outward channel and a return channel. Such a flat tube can be manufactured from the outset as an extrusion with a central web separating the two channels or a plurality of return outward channels and a plurality of return channels. Alternatively, a flat tube may also be extruded without a web and compressed in a central region in its longitudinal direction, and its top and bottom surfaces then be welded together in this central region. The end of the flat tubes not used for connection to the coolant supply line and the coolant discharge line is then closed with a deflector that connects the two channels of the flat tube. Such a deflector may be made of metal or plastic and can, for example, be connected to the flat tubes by means of a push-fit connection or a plug-in connection. Alternatively or additionally, the end piece can also be connected to the relevant flat tube by means of a material bond, for example, in the form of adhesive bonding, soldering or welding.

In an advantageous refinement of this disclosure an end piece of a flat tube may form both a connector for the coolant supply line and also a connector for the coolant discharge line. In this way, the number of parts can be reduced, and thus inexpensive production can be achieved. However, it is also possible to use a separate end piece for each of the channels of the flat tube, each of which is connected only to the coolant supply line or only to the coolant discharge line.

In an advantageous refinement of this disclosure the line segments of the coolant supply line and the coolant discharge line may be connected to the connectors by means of a push-fit connection or a plug-in connection. The connectors may be inserted into the line segments, or the line segments may be inserted into the connectors. The end pieces may carry both a connector, into which one of the line segments is inserted, and also an inner part, which projects into the line segment concerned. The inner part may carry an annular seal, for example, in an annular groove. In this way, not only can leakage be reliably prevented, but manufacturing tolerances with regard to the alignment of the components involved in the push-fit connection or plug-in connection can also be compensated for. In addition, the seal between the line segment and the inner part can be protected by the connector.

Flat tubes, which sit between flat tubes, may be designed with end pieces, which each have connectors on opposite sides for the coolant supply line and the coolant discharge line. Here it is possible for the connectors to be designed identically on both sides, for example, to be designed on both sides as a male part of a push-fit connection or plug-in connection, or designed on both sides as a female part of a push-fit connection or plug-in connection. In one configuration of this disclosure, however, it is also possible for the connectors in each case to be designed on one side of the end piece as a male part of a push-fit connection or plug-in connection, and on an opposite side of the end piece as a female part of a push-fit connection or plug-in connection. In this case it is especially advantageous if an end piece which carries connectors both for the coolant supply line and for the coolant discharge line, the end piece has on each side both a male and a female connector. An assembly of one flat tube with end pieces and connectors can then be in two different orientations, i.e., turned along its longitudinal axis by 180°, for the cooling module.

If an end piece thereby carries both connectors for segments of the coolant supply line, and also for segments of the coolant discharge line, it is also possible on each side of the end piece for both a connector for a male push-fit connection or plug-in connection, and also a connector for a female push-fit connection or plug-in connection, to be provided.

In a cooling module according to this disclosure, it is possible for batteries, or battery cells, on opposite sides to abut against one of the flat tubes. However, if such large cooling capacities are not required, it is also possible for batteries or battery cells to abut against one of the flat tubes only on one side, and on an opposite side to abut against a spacer strip, which runs between two adjacent flat tubes, and is preferably made of plastic. The spacer strip can have an extension, by which it is attached to the coolant supply line and/or the coolant discharge line. The extension may, for example, extend between the coolant supply line and the coolant discharge line. Batteries, or battery cells, may be adhesively bonded to such a spacer strip. Advantageously, the batteries can thus be mechanically fixed by the spacer strip, without impairing the thermal coupling with the flat tube opposite the spacer strip. However, it is also possible for such a spacer strip to be clamped between batteries, or battery cells. Spacer strips may also be used at an end of the cooling module such that all flat tubes are touched on both sides by batteries.

In an advantageous refinement of this disclosure, provision is made for the spacer strips to have the same thickness as the flat tubes. The thickness of a flat tube as well as the thickness of a spacer strip is to be measured between a surface facing batteries or battery cells and an opposite surface, wherein any local recesses or depressions in a surface are to be ignored on both sides. In this context, the term “the same thickness” is to be understood to mean that the thicknesses of the flat tubes and the spacer strips are identical within manufacturing tolerances. For applications in which a reduced cooling capacity is sufficient, and batteries therefore abut against a flat tube on only one side, some flat tubes are replaced by spacer strips.

As described above, this disclosure relates to a cooling module for batteries of an electric or hybrid vehicle, that is to say, a cooling module that has not yet been populated with the appropriate batteries. However, this disclosure also relates to such a cooling module with batteries, that is to say, in particular to a cooling module with a coolant supply line, a coolant discharge line, a plurality of flat tubes arranged side by side, between which the batteries that are to be cooled are arranged, and which are connected to the coolant supply line and the coolant discharge line, wherein the flat tubes in each case carry connectors, and wherein the coolant supply line and the coolant discharge line in each case are assembled from a plurality of line segments, which each connect a connector of one of the flat tubes to a connector of an adjacent flat tube. The line segments may be formed by the connectors or line segments may be separate parts in addition to the connectors.

DESCRIPTION

The embodiments described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of this disclosure.

FIGS.1to5schematically show a detail of a cooling module for batteries of an electric or hybrid vehicle. The cooling module comprises a coolant supply line1, a coolant discharge line2, and a plurality of flat tubes3. The flat tubes3, located in parallel with one another, are connected to the coolant supply line1and the coolant discharge line2. The flat tubes3run at right angles to the coolant supply line1and the coolant discharge line2. Between adjacent flat tubes3there is space for batteries7to be cooled. The batteries7may, for example, be adhesively bonded to the sides of the flat tubes3.

In the embodiment shown, the flat tubes3are of planar design, and are thus adapted to batteries7with a planar outer surface, for example, cuboid batteries. Alternatively, the flat tubes3may also be of corrugated design, for example, for circular cylindrical batteries. The flat tubes3can be made of metal, for example, an aluminium alloy, or plastic.

In the embodiment shown, the coolant supply line1and the coolant discharge line2are arranged at opposite ends of the flat tubes3. The flat tubes3contain one or a plurality of channels extending from one end of the flat tube3to the opposite end. However, it is also possible that the coolant supply line1and the coolant discharge line2are arranged at the same end of the flat tubes3. Then the flat tubes3contain at least two channels, namely an outward channel and a return channel. Channels can be separated in the flat tube3by an inner wall or a weld seam that connects the front and rear sides of a flat tube3. If the coolant supply line1and the coolant discharge line2are at the same end of the flat tubes3, the flat tubes3carry at their end facing away from the coolant supply line1and the coolant discharge line2, the flat tubes3a deflector, not shown in the figures, which connects the outward channel with the return channel. The deflector can be connected to the flat tubes3, for example, by means of a push-fit connection, a plug in-connection and/or a materially bonded connection, for example, in the form of brazing, welding or adhesive bonding.

The coolant supply line1and the coolant return line2are each assembled from a plurality of line segments, and are connected to the flat tubes3by way of connectors6. Therein the connectors may for line segments or the connectors may connect line segments provided as separate parts. At their ends, at which the flat tubes3are connected to the coolant supply line1and the coolant return line2, respectively, the flat tubes3carry an end piece5, which is connected to the flat tubes3by means of a push-fit connection, a plug-in connection and/or by means of a partially bonded connection, for example, in the form of brazing, welding or adhesive bonding. The connectors6are attached to these end pieces5, for example, by means of a partially bonded connection, and/or by means of a push-fit or plug-in connection.

In the embodiment shown inFIGS.1to5, the line segments of the coolant supply line1and the coolant discharge line2are inserted into the connectors6. In the connectors6the line segments can be surrounded by sealing rings12, in order to compensate for tolerances in the alignment of the connectors, and to prevent leakage.

In the embodiment shown inFIGS.1to5, a spacer strip8is arranged between adjacent flat tubes3. In the schematically illustrated cooling module batteries7are then held between one of the flat tubes3and one of the spacer strips8. The batteries7are then cooled on one side only, namely on the side that abuts against the flat tube3in question, while the opposite side is not cooled. This is sufficient for many cases.

The spacer strips8can be made inexpensively of plastic, and can be provided, for example, with an extension11that touches the coolant supply line1and/or the coolant discharge line2, e.g., with an U-shaped extension. If the coolant supply line1and the coolant discharge line2are arranged on the same end of the flat tubes3, the extension11may project between the coolant supply line1and the coolant discharge line2to facilitate positioning during assembly.

An alternative embodiment of the cooling module may also be manufactured without spacer strips. In such an alternative embodiment, batteries7touch flat tubes3on both sides and are cooled on both sides. It is also possible to arrange spacer strips8not between all the flat tubes3, but instead only in an end section of the cooling module.

The cooling module can also be used to heat the batteries by passing heated coolant through the cooling module. In frosty conditions, batteries at the edge of the cooling module often have an increased heating requirement, and it can therefore be advantageous to dispense with spacer strips8only in an end section of the cooling module, and to arrange the flat tubes3at correspondingly smaller distances from one another, so that such batteries abut against flat tubes on both sides.

FIG.4shows detail A ofFIG.3andFIG.5shows detail B ofFIG.3.FIGS.3to5show in detailed views, an end section of a flat tube3of the above-described cooling module, together with an end piece5, attached to the flat tube3and carrying a connector6for purposes of connecting a line section of the coolant supply line1or the coolant discharge line2.

The connector6surrounds an end section of a line segment of the coolant supply line1or the coolant discharge line2. The line segment carries an annular seal12, e.g., an O-ring in a groove.

It is also possible that the end piece5has an inner part in addition to connector6. The connector6surrounds this inner part, which may carry an annular seal10, for example, an O-ring, in an annular groove. The line section of the coolant supply line1or the coolant discharge line2then surrounds this inner part and projects into the connector6, that is to say, it lies between the connector6and the inner part.

FIG.6shows schematically a detail of another embodiment of a cooling module comprising a coolant supply line1, a coolant discharge line2, a plurality of flat tubes3, and spacer strips8. In this embodiment both the coolant supply line1and the coolant discharge line2are arranged on the same side of the flat tubes3. The connectors6arranged at one of the ends of the flat tubes3are stuck into the line segments of the coolant supply line1and the coolant discharge line2, respectively. Hence, the line segments of the coolant supply line1and the coolant supply line2are female parts of a push-fit or plug-connection, whereas the connectors6are male parts of that push-fit or plug-in connection.

FIG.6also shows a spacer strip8that may or may not be used together with the segments of the coolant supply line1, the coolant discharge line2and the flat tubes3.

FIG.7shows a schematic cross-section of the connection of two segments of the coolant supply line1or the coolant supply line2, respectively. As can be seen, connectors6of neighbouring flat tubes3are stuck into a segment of the coolant supply line1(or the coolant discharge line2which may be formed in the same way). This segment surrounds the connectors6and carries on an inside annular seals10. The annular seals10each surround one of the connectors6and press against it.

In the embodiment shown inFIG.7, a separate annular seal10is arranged inside the line segments for each connector6. Alternatively, the annular seal10may also be a single piece that presses against both connectors6.

FIG.8shows a detail of another embodiment of a cooling module for batteries of an electric or hybrid vehicle. This embodiment differs from the embodiment ofFIGS.1to5in that the supply line and the discharge line are formed from connectors of adjacent flat tubes alone. That is the connectors alone form segments of the supply line as well as the discharge and there are no spate tube segments attached to the connectors as shown, e.g., inFIG.4.

As shown inFIG.8, line segments of the supply line and the discharge line are formed by two connectors6a,6bwherein one of these connectors6ais a male connector and the other connector6ba female connector. The male connector6apenetrates into the female connector6b. An annular seal10, e.g., an O-ring may be arranged between the male connector6aand the female connector6b, for example, in a groove of the male connector6a.

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