BATTERY MODULE FOR A TRACTION BATTERY OF AN ELECTRIC VEHICLE, TRACTION BATTERY FOR AN ELECTRIC VEHICLE, AND METHOD OF MANUFACTURING A TRACTION BATTERY

Abstract

A battery module for a traction battery of an electric vehicle is disclosed. The battery module includes at least one heat baffle arranged between two cells of the battery module. A central region of the heat conducting plate is arranged extending in a space between the cells and along a main extension plane of the heat conducting plate. An end region of the heat conducting plate is arranged outside the space and is oriented transversely to the main extension plane and forms a deformable heat transfer surface of the battery module. The end portion is oriented at an acute angle to a reference plane of the heat transfer surface perpendicular to the main extension plane.

Claims

1. A battery module for a traction battery of an electric vehicle, the battery module comprising: at least one heat baffle arranged between two cells of the battery module, wherein a central region of the heat conducting plate extends in a space between the cells along a main extension plane of the heat conducting plate, wherein an end region of the heat conducting plate is arranged outside the space and is oriented transversely to the main extension plane and is configured to form a deformable heat transfer surface of the battery module, and wherein the end portion is arranged at an acute angle to a reference plane of the heat transfer surface perpendicular to the main extension plane.

2. The battery module according to claim 1, wherein the end portion is slotted and is configured to form at least two deformable sub-surfaces of the heat transfer surface.

3. The battery module according to claim 2, wherein adjacent partial surfaces of the end portion are bent in opposite directions.

4. The battery module according to claim 3, further comprising a heat conducting plate arranged in each of at least two intermediate spaces, wherein mutually facing partial surfaces of adjacent heat conducting plates are arranged laterally offset with respect to one another.

5. The battery module according to claim 2, wherein adjacent partial surfaces of the end portion are bent in a same direction.

6. The battery module according to claim 1, wherein two cells are arranged between each of two heat conducting plates.

7. The battery module according to claim 5, wherein the end portions of the two heat conducting sheets are bent in opposite directions.

8. A battery module (102) according to any one of the preceding claims, wherein the end portion (110) forming the heat transfer surface (108) is elastically deformable to a configuration in which the end portion (110) abuts an end surface of one of the cells (106).

9. A traction battery for an electric vehicle, comprising: a temperature control device, at least one battery module comprising at least one heat baffle arranged between two cells of the battery module, wherein a central region of the heat conducting plate extends in a space between the cells along a main extension plane of the heat conducting plate, wherein an end region of the heat conducting plate is arranged outside the space and is oriented transversely to the main extension plane and is configured to form a deformable heat transfer surface of the battery module, and wherein the end portion is arranged at an acute angle to a reference plane of the heat transfer surface perpendicular to the main extension plane, and wherein the heat transfer surface is arranged pressed against the temperature control device with a setting force, such that the heat transfer surface is at least partially deformed by the setting force and at least partially bearing flat against the temperature control device.

10. A method of manufacturing a traction battery, the method comprising the steps of: providing a temperature control device, providing at least one battery module comprising at least one heat baffle arranged between two cells of the battery module, wherein a central region of the heat conducting plate extends in a space between the cells along a main extension plane of the heat conducting plate, wherein an end region of the heat conducting plate is arranged outside the space and is oriented transversely to the main extension plane and is configured to form a deformable heat transfer surface of the battery module, and wherein the end portion is arranged at an acute angle to a reference plane of the heat transfer surface perpendicular to the main extension plane, and wherein the heat transfer surface is arranged pressed against the temperature control device with a setting force, such that the heat transfer surface is at least partially deformed by the setting force and at least partially bearing flat against the temperature control device, and wherein a heat transfer surface of a battery module comprising at least one heat baffle arranged between two cells of the battery module, wherein a central region of the heat conducting plate extends in a space between the cells along a main extension plane of the heat conducting plate, wherein an end region of the heat conducting plate is arranged outside the space and is oriented transversely to the main extension plane and is configured to form a deformable heat transfer surface of the battery module, and wherein the end portion is arranged at an acute angle to a reference plane of the heat transfer surface perpendicular to the main extension plane, such that the battery module is pressed against the temperature control device with a setting force, and wherein the heat transfer surface is at least partially deformed by the setting force and is at least partially applied a really to the temperature control device.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0027] Further advantages, features, and details of the various embodiments of this disclosure will become apparent from the ensuing description of a preferred exemplary embodiment and with the aid of the drawings. The features and combinations of features recited below in the description, as well as the features and feature combination shown after that in the drawing description or in the drawings alone, may be used not only in the particular combination recited, but also in other combinations on their own, without departing from the scope of the disclosure.

[0028] An advantageous embodiment of the present invention is set out below with reference to the accompanying figures, wherein:

[0029] FIG. 1 depicts a sectional view of a traction battery according to an embodiment;

[0030] FIG. 2 depicts a detail of a battery module according to an embodiment; and

[0031] FIG. 3 depicts an illustration of a battery module according to an embodiment.

[0032] The figures are merely schematic representations and serve only to explain the invention. Identical or similarly acting elements are marked throughout with the same reference signs.

DETAILED DESCRIPTION OF THE INVENTION

[0033] As used throughout the present disclosure, unless specifically stated otherwise, the term “or” encompasses all possible combinations, except where infeasible. For example, the expression “A or B” shall mean A alone, B alone, or A and B together. If it is stated that a component includes “A, B, or C”, then, unless specifically stated otherwise or infeasible, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C. Expressions such as “at least one of” do not necessarily modify an entirety of the following list and do not necessarily modify each member of the list, such that “at least one of “A, B, and C” should be understood as including only one of A, only one of B, only one of C, or any combination of A, B, and C.

[0034] FIG. 1 shows a sectional view of a traction battery 100 according to an embodiment. The traction battery 100 may include a plurality of battery modules 102. Here, one of the battery modules 102 is shown in a cutaway view. The battery modules 102 may be connected in parallel and/or in series in the traction battery 100. For this purpose, the individual battery modules 102 are inserted into a housing or frame of the traction battery 100 and electrically connected to each other. For temperature control of the battery modules 102, the traction battery 100 has a temperature control device 104, which may, for example, be arranged in a base of the housing or may form the base of the traction battery 100. In particular, the temperature control device 104 may be used to cool the battery modules 102. At low temperatures, the temperature control device 104 may also be used to heat the battery modules 102.

[0035] The battery module 102 includes a plurality of pouch cells or prismatic cells 106. The cells 106 are arranged flat side to flat side, side by side, within a housing of the battery module 102. The flat sides of the cells 106 are oriented perpendicular to a heat transfer surface 108 of the battery module 102. Here, the heat transfer surface 108 is disposed at a bottom of the housing. The battery module 102 is thermally coupled to the temperature control device 104 via the heat transfer surface 108. The battery module 102 may be coupled to the temperature control device 104 using a heat transfer material not shown here.

[0036] Alternatively, the cells 106 may be stacked horizontally on top of each other. In that case, the battery module 102 may include at least one side heat transfer surface 108. Depending on the design of the temperature control device 104, the battery module 102 may also have multiple heat transfer surfaces 108 disposed on different sides of the battery module 102.

[0037] In the approach presented herein, the heat transfer surface 108 is formed by folded end regions 110 of heat conduction plates 112 of the battery module 102. Central regions 109 of the heat conduction plates 112 thereby extend in a space between adjacent cells 106 and extend along a main extension plane of the respective heat conduction plate 112. The end regions 110 are thereby not bent perpendicularly to the central regions 109 of the heat conduction plates 112, but extend at an angle different from 90°, i.e., at an oblique angle. The end regions 110 are thus oriented at an acute angle with respect to a reference plane of the heat transfer surface 108 extending perpendicularly to the main extension plane of the heat transfer sheets 112. The end regions 110 thereby extend beyond side portions of the battery module 102. In other words, the side portions stand back from the reference plane.

[0038] Due to the acute angle, the end regions 110 hit the temperature control device 104 with one edge first when the battery module 102 is placed. Due to a weight of the battery module 102 and/or a setting force, the end regions 110 are deformed and adapt to the temperature control device 104. The end regions 110 thereby compensate for tolerances in shape and position of the temperature control device 104 and the battery module 102. In essence, the end regions 110 are flex springs and deform at least slightly elastically in each case. The end regions 110 may also deform plastically proportionately if a bending moment resulting from the weight and/or settling force is greater than a bending resistance moment of the end regions 110. It is also possible for the end regions to be arranged in parallel.

[0039] The deformation of the end portions 110 increases a contact area between the heat transfer surface 108 and the temperature control device 104.

[0040] In one embodiment, two cells 106 are disposed between each of two heat baffles 112. Thus, a heat conducting plate 112 is arranged between every second cell 106. The end regions 110 of adjacent heat conducting sheets 112 are thereby bent in opposite directions. Thus, the edges of each of two end regions 110 are directed toward each other and these end regions 110 form a ridge 114 of the heat transfer surface 108. The folded end regions 110 are shorter than a thickness of the cells to prevent contact between the edges. The edges are thereby disposed on either side of a center of the rib 114. The rib 114 has a gap between the edges at the center. A cavity 116 is thereby arranged between each two ribs 114 for receiving excess heat conducting material.

[0041] In an alternative embodiment, heat baffles 112 are disposed between all cells 106 of the battery module 102. This allows the cells to be tempered from both flat sides. The end regions 110 are beveled in the same direction in each case to avoid collisions.

[0042] FIG. 2 shows a detail of a battery module 102 according to an embodiment. The battery module is substantially the same as the battery module shown in FIG. 1, where two bent end portions 110 of two heat baffles 112 are shown protruding from the spaces between the cells 106. The portions of the heat conducting sheets 112 projecting from the interstices form an elastic and/or deformable region that can be deformed when the battery module 102 is placed on the temperature control device. In this regard, the end portions 110 oriented obliquely to the reference plane define a spring path or deformation path for the deformation.

[0043] FIG. 3 shows an illustration of a battery module 102 according to an embodiment. The battery module is substantially the same as the battery module in FIGS. 1 and 2. Here, the heat transfer surface 108 of the battery module 102 is shown. Here, the end regions 110 are slotted. The slots divide the end regions 110 into individually deformable sub-surfaces 300. The sub-surfaces can deform during placement according to the portion of the placement force acting on them. This allows the heat transfer surface 108 to adapt well to a contour of the temperature control device.

[0044] In one embodiment, the partial surfaces 300 of a heat conducting sheet 112 are each beveled in the same direction. Thus, the heat conducting sheet 112 can be easily manufactured. The heat conducting sheets 112 with their end portions 110 form ribs 114 as in FIG. 1.

[0045] In an alternative embodiment, the partial surfaces are bent alternately in opposite directions while maintaining the acute angle to the reference plane. In this case, the partial surfaces 300 are each beveled by less than 90 degrees. Free ends of the partial surfaces are thus directed away from the cells 106, respectively. Due to the alternating orientation of the partial surfaces 300, bending moments introduced during placement on the tempering device cancel each other out. Thus, a compressive load on the cells 106 adjacent to the heat conducting plate 112 can be reduced.

[0046] In one embodiment, the partial surfaces 300 of adjacent heat transfer plates 112 are laterally offset from each other. Thus, the heat transfer surface 108 is arranged uniformly across the bottom of the battery module 102. The partial surfaces 300 are arranged in a regular pattern.

[0047] In other words, a battery module with a heat spreader with an integrated tolerance compensation is presented.

[0048] To manufacture a traction battery, cell modules are inserted into a frame or battery housing and thermally bonded to a cooling element (e.g. cooling plate) in the process. Geometric tolerances and flatness of both components can prevent a uniform contact surface and thus a uniform thermal connection.

[0049] The approach presented here therefore uses heat-conducting sheets that have an elastic or deformable area to the cooling element. The elastic or deformable area is deformed when the cell modules are placed and thus creates a uniform thermal contact surface.

[0050] In addition, pasty or deformable TIM (Thermal Interphase Material) materials such as gap fillers or gappads can be used. With the approach presented here, the use of gap fillers can be avoided or greatly reduced, resulting in cost savings.

[0051] The elastic or deformable areas thus enable the elimination of additional materials, simplification of the production process and an increase in the thermal performance of cell modules.

[0052] The individual heat conducting plate in a cell module has an elastic or deformable area on at least one side. The cell module consists, for example, of pouch cells that are in thermal contact with the heat conducting sheet. In assembly, the cell module is in thermal contact with a cooling structure. The elastic or deformable region is deformed when the module is assembled to the cooling structure. The elastic area can be structured to create bending fingers that have a defined bending zone, thus ensuring a defined contact area with the cooling element. The cell module can be used in particular in a battery for a vehicle.

[0053] Since the devices and methods described in detail above are examples of embodiments, they can be modified in the usual manner by the skilled person to a wide extent without leaving the scope of the invention. In particular, the mechanical arrangements and the proportions of the individual elements with respect to each other are merely exemplary.

[0054] Since the devices and methods described in detail above are examples of embodiments, they can be modified to a wide extent by the skilled person in the usual manner without leaving the scope of the invention. In particular, the mechanical arrangements and the proportions of the individual elements with respect to each other are merely exemplary. Some preferred embodiments of apparatus according to the invention have been disclosed above. The invention is not limited to the solutions explained above, but the innovative solutions can be applied in different ways within the limits set by the claims.