DE102019212861A1 - Battery module for a motor vehicle, manufacturing method for a battery module and motor vehicle with a battery module - Google Patents

Abstract

The invention relates to a battery module (10) for a motor vehicle (12) and a manufacturing method for such a battery module (10). The battery module (10) comprises a plurality of battery cells (14) and a cooling device (18) which comprises a flexible hose (20) through which a coolant can flow and which has an insertion state in which the hose (20) is not separated from the Coolant is flowed through, and a propagation state in which the hose (20) is flowed through by the coolant, comprises. In the state of introduction, the hose can be arranged between the battery cells (14) and, after being introduced between the battery cells (14), can adapt to an outer surface of the respective battery cell in the state of expansion.

Description

The invention relates to a battery module for a motor vehicle, a manufacturing method for a battery module and a motor vehicle with such a battery module.

Battery modules are currently equipped with shaped cooling lines made of metal, so-called multiport tubes, in order to cool the battery cells of the battery module. In order to compensate for a tolerance between the battery cells and the multiport tubes, the battery cells are wetted with a thermal paste, a so-called gap filler, so that the preformed multiport tube connects to the battery cell to ensure optimal heat transfer and passage. This in turn prevents the battery cells from moving freely, making them prone to vibrations. In addition, an assembly process of such battery modules is very complex, since the adhesive bonding of the battery cells and the application of the thermal paste must be very well coordinated. Exchanging individual battery cells from the battery module and reprocessing battery cells that have already been coated and bonded with the thermal paste can only be carried out at great expense.

From the DE 10 2014 200 832 A1 A heat sink with a cooling space is known, the cooling space being delimited on at least one surface side that delimits the cooling space by means of a mechanically tensioned flexible flat membrane, into which the component to be cooled can be displaced from outside the cooling space in such a way that the flexible flat membrane changes shape over a large area and mechanically adapts contacting to a surface to be cooled of the object to be cooled.

From the DE 10 2015 110 667 A1 a cell arrangement with a plurality of battery cells designed as pocket cells is known, the pocket cells having a cell casing made of a foil material, the foil material of the cell casing being folded in a line and the remaining open edge areas of the foil material of the cell casing lying on top of one another being tightly welded, with two Opposite edge areas of the respective cell casing of the pocket cells are each contacted by a cooling element for cooling the pocket cells, the pocket cells each resting against the opposing cooling elements with an edge area with welding of the film material and with an edge area with folding of the poly material.

From the EP 2 744 034 A1 a heat exchanger arrangement is known, the heat exchanger of which is designed as a heat exchange pocket which has an inflow and outflow channel and is in thermally conductive contact with inner surfaces of the object to be temperature-controlled.

The object of the present invention is to provide a battery module that can be produced and / or maintained easily and inexpensively.

The invention is solved by the independent patent claims. Advantageous further developments of the invention are disclosed by the dependent claims, the figures and the description.

The invention relates to a battery module for a motor vehicle with a plurality of battery cells and with a cooling device which comprises a flexible hose which is designed to allow a coolant to flow through it. The flexible hose can include an insertion state in which the hose is not flowed through by the coolant, and a spreading state in which the hose is flowed through by the coolant, wherein the hose is further designed to be arranged between the battery cells in the insertion state and adapt to an outer surface of the respective battery cell in the spreading state after being introduced between the battery cells.

In other words, the battery module can have a plurality of battery cells which, for example, can generate heat during a charging process and / or a power call-up, wherein the heat can be absorbed and transported away by the cooling device of the battery module. For this purpose, the cooling device can have a flexible hose which is arranged on the battery cells and which is designed to allow a coolant, for example a water-glycol mixture or other liquid coolants, to flow through it. The hose is also designed to expand when the coolant flows through and thus to adapt to an outer surface of the respective battery cell.

In the insertion state of the hose, in which no coolant flows through the hose and therefore there is no increased pressure inside the hose, the hose can easily be shaped or curved in order to arrange the hose on the battery cells. For this purpose, the tube can, for example, be wrinkled or creased in the state of introduction. The folds of the hose can unfold in the expanded state when the coolant flows through the hose and there is thus pressure in the hose, with the result that the outside of the Spreads hose and can adapt to an outer surface of the respective battery cell. Furthermore, the expansion can also include an expansion of the material of the hose. This means that the hose advantageously has a certain degree of elasticity, which allows the hose to expand under the coolant pressure and thus to be pressed against the outer surface of the respective battery cell. Preferably, the hose can brace the battery cells in its expanded state. In this case, the battery cells are fixed in their position by the expanded tube through the expanded tube. This has the advantage that an impact on the battery module can be cushioned elastically and damage to the battery cells can be reduced. The hose can thus be used to tension the cells so that they can no longer move and are decoupled from impacts.

To cool the plurality of battery cells, the flexible hose can easily be arranged in spaces between the battery cells so that it rests against a desired surface of the battery cells. The hose can then be put into the spreading state, whereby it spreads and / or expands and thus clings to the battery cells. The flexible hose of the cooling device can in particular be formed from a thermally conductive material. A plastic and / or a metal, for example, can be used for this purpose. Furthermore, the hose can unfold and / or expand when an internal pressure increases. The hose can have a round cross-section, but it can preferably be provided that the hose has an elongated cross-section which, for example, can cover a height of a side surface of the battery cell in its height, but is narrow in its width in order to be arranged in spaces between the battery cells to become.

The invention has the advantage that the cooling device, which is designed as a flexible hose, can easily be introduced between the battery cells during the production of a battery module. The flexible hose also means that the expensive gap filler can be dispensed with, since the hose can compensate for tolerances in the expanded state and ensures effective heat dissipation. Impacts on the battery cells can also be elastically absorbed and cushioned by the expanded hose, which improves the impact sensitivity of the battery module. Furthermore, battery cells can easily be changed even after the battery module has been installed, as no gap filler has to be removed. In this case, the hose can, for example, be put into the insertion state, as a result of which the battery cells can easily be detached from the battery module.

Further advantageous developments of the invention, which result in additional advantages, are described in the following embodiments.

In one embodiment it is provided that the plurality of battery cells are round cells and the flexible hose is formed from film elements which, in the state of expansion, adapt radially to a lateral surface of the respective round cell. In other words, the battery cells are round cells, that is to say cylindrical battery cells, which can for example be arranged in rows next to one another and on the side surface of which the flexible hose is arranged. The hose can be formed from film elements. This means that, for example, two foils are placed on top of one another and welded to one another on two opposite sides, so that a foil sack or a tube is formed through which the coolant can flow. In the spreading state, the foils can then adapt radially to a respective lateral surface of the round cells. The foils can, for example, be guided laterally along a row of round cells. In particular, round cells arranged next to one another can form an interspace or a joint that is difficult to reach through the cooling device. Due to the expansion of the hose in the expanded state, this gap or this joint can be reached by the cooling device and thus cooled. However, it is also possible that the foils are laid in a meandering shape around each individual round cell and, in the state of expansion, adapt to the respective outer surface of the round cell. The flexible hose can in particular cover more than 50% of the height of a round cell, preferably 90 to 100% of the height of a round cell. This embodiment has the advantage that the hose can be adapted to the geometry of the battery cell, in particular to the outer surface of a round cell, which would otherwise only be possible by introducing a gap filler. A cooling device for round cells can thus be provided in a simple manner, and costs can be saved in the production of the battery module.

Another embodiment provides that the hose is designed as a single endless hose. In other words, all of the battery cells are cooled by a single endless tube which runs between the battery cells without interruption, in particular without interruption by a coupling and / or a plug. This embodiment has the advantage that no connection technology is required to cool the battery cells, which reduces the likelihood of selection due to possible leaky connections.

Another embodiment provides that the hose is made of plastic and / or aluminum. For example, the hose can be made of several plastic films that are welded on at least two sides or made of thin aluminum sheets that can expand under pressure. An advantage of aluminum sheets, which can form a foil bag made of metal, is that they have an improved thermal conductivity compared to plastic. A hybrid film made of plastic and aluminum is also possible for use as a hose.

Another embodiment provides that the hose is divided into at least two chambers, each of the chambers being designed for the coolant to flow through. In other words, a plurality of chambers through which the coolant can flow and through which the coolant can flow separately from one another can be provided within the hose. A subdivision of the hose into at least two chambers can be achieved, for example, in that a seam is provided within the hose, which seam can divide the hose into two or more halves. For example, it can be provided that a liquid coolant flows through the at least two chambers in the same direction. However, it can also be provided that the coolant flows in the forward direction through one of the at least two chambers and the coolant is guided in the reverse direction through the other of the at least two chambers. Thus, for example, an inflow and outflow of the coolant can be provided at the same point, whereby space can be saved. Another advantage of this embodiment is the improved statics of the hose.

It is preferably provided that the hose has a wall thickness in a range from 0.05 mm to 0.5 mm, in particular in a range from 0.2 to 0.3 mm. These wall thicknesses have proven to be particularly suitable for ensuring stability of the hose and, at the same time, efficient heat transfer from the battery cell to the coolant.

One embodiment provides that the hose comprises a microstructured surface on an inside and / or outside. This means that the hose can have, for example, a roughened and thus enlarged surface on an inside and / or outside, as a result of which heat transport from the outside to the inside of the hose is improved. This embodiment has the advantage that heat can be better absorbed by the battery cells and thus transported away.

Another embodiment provides that the battery module furthermore has an injection-molded element which is designed to hold the battery cells and the hose in position, and wherein the hose has a pre-stamped shape that is adapted to the battery cells. In other words, an injection-molded element can be provided in which the battery cells and the hose can be positioned, the hose already having an embossing that is adapted to the shape of the battery cells. The injection molded element can preferably be made of plastic. This embodiment has the advantage that the hose in the expanded state can be adapted even more precisely to an outside of the battery cells, as a result of which the cooling performance of the cooling device is improved. In addition, production of the battery module can be facilitated by the injection-molded element, since the cells and the hose can be easily arranged in the injection-molded element.

According to the invention, a manufacturing method for a battery module is also provided, the battery module comprising a plurality of battery cells and a cooling device, the cooling device having a flexible hose through which a coolant can flow, the hose in an insertion state of the hose in which the hose is not flowed through by the coolant, is arranged between the battery cells, and wherein the hose is adapted to an outer surface of the respective battery cell after being introduced between the battery cells in a spreading state in which the hose is flowed through by the coolant. This embodiment results in the same possible variations and advantages as with the battery module.

Another aspect of the invention relates to a motor vehicle with a battery module according to one of the preceding embodiments. The motor vehicle according to the invention is preferably designed as a motor vehicle, in particular as a passenger vehicle or truck, or as a passenger bus or motorcycle.

The invention also includes further developments of the method according to the invention which have features as they have already been described in connection with the further developments of the motor vehicle according to the invention. For this reason, the corresponding developments of the method according to the invention are not described again here.

The invention also includes the combinations of the features of the described embodiments.

• 1 eine schematische Draufsicht auf ein Batteriemodul gemäß einer beispielhaften Ausführungsform;
• 2 eine schematische Seitenansicht eines Batteriemoduls gemäß einer beispielhaften Ausführungsform;
• 3 ein schematisches Verfahrensdiagramm gemäß einer beispielhaften Ausführungsform.

Exemplary embodiments of the invention are described below. This shows:

• 1 a schematic plan view of a battery module according to an exemplary embodiment;
• 2 a schematic side view of a battery module according to an exemplary embodiment;
• 3rd a schematic process diagram according to an exemplary embodiment.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention which are to be considered independently of one another and which also further develop the invention in each case independently of one another. Therefore, the disclosure is also intended to include combinations of the features of the embodiments other than those illustrated. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

In the figures, the same reference symbols denote functionally identical elements.

In 1 Figure 3 is a schematic top view of a battery module 10 for a motor vehicle 12th shown. The car 12th , which is indicated schematically in this figure, can in particular be a battery-operated electric motor vehicle.

The battery module 10 can have a plurality of battery cells 14th have, in this embodiment, round cells 14th could be. The round cells 14th can on an injection molded element 16 , which is made of plastic, for example, are arranged and held. In particular, the round cells 14th on the injection molding element 16 be arranged next to one another in the radial direction, so that rows of round cells 14th result, wherein a gap can be formed between two rows.

For cooling the round cells 14th can be a cooling device in the space 18th be provided having a flexible hose 20th includes. The flexible hose 20th can be designed to have a coolant, preferably a fluid, such as water or a water-glycol mixture flowing through it. The cooling device 18th for example have a coolant pump (not shown) which pumps the coolant through the flexible hose.

The flexible hose 20th can have at least two states, an introduction state in which the hose is not flowed through by the coolant and in which the hose 20th flexible in the space between the round cells 14th can be arranged, and a state of expansion in which the hose 20th is traversed by the coolant, the hose being able to spread and / or expand when the coolant flows through and thus to an outer surface, in particular radially to a lateral surface of the respective round cell 14th , can customize.

The hose 20th be wrinkled in its state of introduction, for example, with the hose moving with a change in the internal pressure that occurs when the hose 20th is traversed by the coolant, can unfold and thus expand. As a result of this elastic expansion, an outer wall of the hose can expand until it reaches a lateral surface of a respective round cell 14th meets, on the surface of which the hose can then adapt or nestle. In this way, a form-fitting or shape-adapted contact can be made for optimal heat transfer from the round cell 14th to the coolant in the hose 20th can be achieved.

The flexible hose 20th can preferably be formed from foil elements, in particular by means of foil elements made of plastic and / or aluminum. This has the advantage that these materials can be processed inexpensively and have the desired flexibility. Furthermore, aluminum has a high coefficient of thermal conductivity, which enables increased heat dissipation. A wall thickness of the respective film elements, which can be welded to one another on opposite sides, for example, so that a hose through which the coolant can flow results, can be in a range from 0.05 to 0.5 mm, particularly preferably in a range from 0, 2 to 0.3 mm.

In addition, the hose 20th be designed as a single endless hose, which means that the hose 20th in the battery module 10 around or along all round cells 14th can be arranged without being interrupted by a coupling and / or a plug, which minimizes the probability of failure of the battery module due to potentially leaky connections. The hose can preferably 20th laterally along a row of round cells 14th and at the end of the row around the last round cell 14th be arranged around so that it runs back on the other side of the row of round cells. This can then be used for any row of battery cells can be applied. This ensures that each of the round cells 14th from the hose 20th is reached and thus cooled.

To a cooling capacity of the cooling device 18th in addition to increasing, the hose can 20th have a microstructured surface on its inside and / or outside. That means that the hose by increasing the surface area with the round cells 14th and / or the coolant is in contact, can have an improved thermal conductivity. A microstructured surface can comprise a roughened material, for example. Optical exposure methods, in particular holographic exposure methods, or embossing methods, for example, can be used to produce the microstructured surface.

The cooling device shown here is particularly advantageous 18th as the flexible hose 20th as cooling easily in the gaps or free spaces between the round cells 14th can be fitted without the need to use a heat-conducting medium such as a gap filler. Alternatively, the round cells 14th can be inserted into the gaps of a pre-stamped hose without using a gap filler. When exchanging the round cells 14th can the hose 20th for example, put in its introduction state, whereby the round cells 14th can be removed or exchanged reversibly and non-destructively from the battery module.

In 2 Fig. 3 is a side view of the battery module 10 with a plurality of round cells 14th shown schematically. In addition, there is a section of the flexible hose along the side of the round cells 20th shown.

The flexible hose 20th can preferably be the same height as the round cells 14th have or at least 90% of the height of the round cells. This can be done during the manufacture of the hose 20th one or more foil elements with a suitable height can be selected. For example, two very thin aluminum sheets can be used, which are welded tightly on a lower and an upper side, so that a longitudinal seam results that the hose 20th seals up and down.

Preferably it can be in the middle of the hose 20th an additional longitudinal seam 22nd be provided that the hose 20th divided into at least two chambers through which the coolant can flow. This results in better static properties for the hose 20th and it can be provided, for example, that one chamber conducts the coolant in the forward direction and the other chamber conducts the coolant in the reverse direction. This has the advantage that the coolant can be fed in and out at the same point. Furthermore, it is also possible to use the method described by way of example to create further chambers within the hose 20th to create.

In 3rd an exemplary manufacturing method for a battery module is shown. The battery module 10 can have a plurality of battery cells 14th and a cooling device 18th have, wherein the cooling device comprises a flexible hose 20th has through which a coolant can flow.

In one step S10 can the hose 20th in an insertion state of the hose in which the hose 20th is not flowed through by the coolant, between the battery cells 14th to be ordered.

Then the hose 20th after insertion between the battery cells 14th as a step S12 in a spreading state in which the hose is flowed through by the coolant, on an outer surface of the respective battery cell 14th be adjusted.

Overall, the examples show how the invention can provide a battery cell with active radial cooling.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102014200832 A1 [0003]
• DE 102015110667 A1 [0004]
• EP 2744034 A1 [0005]

Claims (10)

Battery module (10) for a motor vehicle (12) with - A plurality of battery cells (14); and with - A cooling device (18) which comprises a flexible hose (20) which is designed to have a coolant flowing through it and which has an introduction state in which the hose (20) is not flowed through by the coolant, and a spreading state, in which the hose (20) is flowed through by the coolant, wherein the hose (20) is further designed to be arranged in the insertion state between the battery cells (14) and after being inserted between the battery cells (14) in the Adapt the state of propagation to an outer surface of the respective battery cell. Battery module (10) Claim 1 , wherein the plurality of battery cells are round cells (14) and wherein the flexible hose (20) is formed from foil elements which adapt radially to a lateral surface of the respective round cell in the state of expansion. Battery module (10) according to one of the preceding claims, wherein the hose (20) is designed as a single endless hose. Battery module (10) according to one of the preceding claims, wherein the hose (20) is made of plastic and / or aluminum. The battery module (10) according to any one of the preceding claims, wherein the hose (20) is divided into at least two chambers, each of the chambers being designed for the coolant to flow through. Battery module (10) according to one of the preceding claims, wherein the hose (20) has a wall thickness in a range from 0.05 mm to 0.5 mm, in particular in a range from 0.2 to 0.3 mm. Battery module (10) according to one of the preceding claims, wherein the hose (20) comprises a microstructured surface on an inside and / or outside. The battery module (10) according to any one of the preceding claims, wherein the battery module (10) further comprises an injection-molded element (16) which is designed to hold the battery cells (14) and the hose (20) in position, and wherein the hose ( 20) has a pre-embossed shape which is adapted to the battery cells (14). Manufacturing method for a battery module, wherein the battery module comprises a plurality of battery cells and a cooling device, wherein the cooling device has a flexible hose through which a coolant can flow; wherein the hose is arranged (S10) between the battery cells in an insertion state of the hose in which the hose is not flowed through by the coolant, and wherein the hose, after being inserted between the battery cells, is in a spreading state in which the hose is flowed through by the coolant , is adapted to an outer surface of the respective battery cell (S12). Motor vehicle (12) with a battery module (10) according to one of the Claims 1 to 8th .

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