CN108630853B

CN108630853B - Battery module, battery and method for producing battery module

Info

Publication number: CN108630853B
Application number: CN201810235365.0A
Authority: CN
Inventors: A.勒姆克; L.拉肯马赫; B.沙尔; F.维谢
Original assignee: Volkswagen AG
Current assignee: Volkswagen AG
Priority date: 2017-03-21
Filing date: 2018-03-21
Publication date: 2022-06-07
Anticipated expiration: 2038-03-21
Also published as: CN108630853A; DE102017204724A1

Abstract

The invention particularly relates to a battery module (5), wherein the battery module (5) comprises a battery cell substrate (7) and a plurality of battery cells (6) arranged on the battery cell substrate (7), wherein the battery cells (6) each comprise a battery cell housing (8) and at least one battery cell coil (9) arranged in the battery cell housing (8). It is advantageously provided that the cell housings (8) of a plurality of battery cells (6) are each configured in a cup-shaped manner and in one piece with the cell base plate (7).

Description

Battery module, battery and method for producing battery module

Technical Field

The present invention relates to a battery module. The invention further relates to a battery pack having at least one battery module of this type. The invention further relates to a method for producing a battery module of this type.

Background

Lithium ion batteries having a cell coil arranged in a stationary housing, i.e. a cell housing, as a core component of an electrical cell, have been known for a long time from the prior art. For this purpose, the individual layers of the battery cell are stacked on top of one another and subsequently wound around a mandrel. The cylindrical cell coil, also referred to as a jellyroll, is then packed into a stationary housing with a circular cross section, which is usually also the current collector for the negative electrode. The positive electrode is constituted via a cover insulated from the case. This type of lithium ion battery cell is also referred to as a round battery cell. Furthermore, so-called prismatic battery cells are also known. In this case, the cell coil is not wound around the mandrel, but rather is wound flat, although the majority of cells are also wound. The flat coil produced in this case is packed in a prismatic housing. The electrodes are usually contacted through the cover of the housing in an insulated manner from the housing (see doctor Michael Buser (Risko Experts Risiko Engineering GmbH) and Jochen M ä hli beta doctor ((Battery university private GmbH)), "lithium battery combustion hazard and safety risk", 2016 year 4, first edition, page 9 in particular, points 1.4, -http:// www.batteryuniversity.eu/publishing/DE _ index _1194. html). Furthermore, a battery pack with a heat conducting plate for controlling the temperature of the battery pack is known from DE 102007010743B 3, which has a plurality of electric cells in the form of round battery cells electrically connected to one another in parallel and/or in series. The round battery cells are arranged in a battery housing which is in particular completely closed. The unit cells are arranged on a heat-conducting plate configured as a metal plate. In the heat-conducting plate, a channel structure is arranged which can be used for the flow-through of the heat-conducting medium. The arrangement of the cell units on the heat-conducting plate is realized in such a way that their longitudinal axes are parallel to one another. Document DE 102008059967 a1 describes a battery pack with a thermally conductive plate arranged in the battery pack housing. In this case, a plurality of cell units in the form of round cells, which are electrically connected to one another in parallel and/or in series and form a cell composite (Zellenverbund), are also provided, which are connected to a heat-conducting plate in a thermally conductive manner and are fastened to the latter on the upper side and/or the lower side. For this purpose, the battery housing has a base plate with profiled edges and recesses for the battery cells. The single battery cells are arranged with the pole sides facing the heat conducting plate, so that the two pole contacts of each single battery cell pass through the associated recesses. A thermally conductive and electrically insulating molded body is arranged between the thermally conductive plate and the cell composite.

Disclosure of Invention

It is an object of the present invention to design a battery module alternative to the prior art in such a way that the costs are reduced. Furthermore, it is an object of the invention to provide a battery pack with at least one battery module of this type. Furthermore, it is an object of the present invention to provide a method for manufacturing a battery module of this type.

According to a first advantageous embodiment variant of the invention, a battery module is provided with a cell base plate and a plurality of battery cells arranged on the cell base plate, wherein the battery cells each have a cell housing and at least one battery cell coil arranged in the cell housing, and the object is achieved in that the cell housings of the plurality of battery cells are each configured cup-shaped and in one piece with the cell base plate.

A cup-shaped battery cell housing is understood here to mean a battery cell housing having a battery cell base and a surrounding battery cell wall which is preferably arranged perpendicular to the battery cell base. Thereby, a battery module is achieved, in which the costs of the battery module are reduced in terms of its manufacture due to the minimized number of components. In particular, this results in structural space, weight and cost advantages. Furthermore, by this measure, the heat transfer between the possibly provided temperature control medium, in particular the cooling medium, and the battery cell is advantageously reduced. Furthermore, an optimization of the electrical connection and the electrical coupling, preferably the parallel connection, of the battery cells of the battery module constructed according to the present invention is achieved, since, for example, welding processes at the finished battery cells, such as are recommended according to the prior art, are avoided.

The formed cell housing then preferably has a circular or polygonal, in particular rectangular or square, cross section, whereby round or prismatic battery cells can be produced according to the current requirements. A circular cross section is to be understood to mean not only a circular cross section but also a more or less rounded cross section, for example an oval cross section. According to a first preferred embodiment of the cell housing, each of the cells is formed by a tube which extends from the cell substrate perpendicularly to the cell substrate and is closed at one end by the cell substrate, the tube having a circular or polygonal cross section. The free space between the tubular cell housings, through which the temperature control fluid flows, can be used in other respects, for example, for temperature control of the battery cells. The cell base plate together with the cell housing, which is formed in one piece with the cell base plate, is produced, for example, according to a 3D printing method or a casting method. According to a second advantageous embodiment of the battery cell housing with a circular or polygonal cross section, each of these is formed by a cup-shaped cavity in a common, compact material block of the battery cell base plate. That is to say, the dimensions of the cell substrate are dimensioned such that the cavity for representing the cell housing and the cup-shaped cavity accommodating the cell coil is constructed solely by, for example, machining the material block, for example, drilling or milling. In contrast, compact battery cell substrates of this type can also be produced according to 3D printing methods or according to a casting process. By this measure, a particularly resistant battery module can be constructed. In order to achieve a simple and cost-effective electrical contacting of the battery cells, it is provided in a development of the invention that the battery cell base plate together with the battery cell housing is electrically conductive and has one electrode of the battery module by means of an electrode connection, and conversely that the other electrode is provided by an electrode connection of the battery module or of the battery pack having at least one battery module, each of which closes the associated battery cell housing together with the battery cell winding and which is electrically insulated relative to the battery cell housing, or by an electrode connection of a common cover element of the battery module or of the battery pack having at least one battery module, which closes the battery cell housing and which is electrically insulated relative to the battery cell housing. Alternatively, it is provided that the two electrodes are provided by means of separate electrode connections by cover elements of the battery module or of the battery pack having at least one battery module, which cover elements each enclose the associated battery cell housing together with the battery cell coil, or by common cover elements of the battery module or of the battery having at least one battery module, which cover elements each enclose a battery cell housing. Furthermore, it is also possible and encompassed by the invention to configure the closed cell substrate together with the cell housing and/or the cover element of the cell housing or the common cover element to be electrically non-conductive, but to have an electrically conductive structure for electrically coupling the battery cells that have been formed. In order to achieve an active temperature control of the battery cells, it is furthermore preferably provided that at least the cell substrate has at least one channel structure through which a medium can flow for temperature control of the battery cells of the battery module.

According to a second advantageous embodiment of the invention, starting from a battery module with a cell base plate and a plurality of battery cells arranged on the cell base plate, wherein the battery cells each have a cell housing and at least one battery cell coil arranged in the cell housing, the object is achieved in that the cell housings of the plurality of battery cells are formed in one piece by an extruded profile, and the extruded profile is connected or can be connected to a separately produced cell base plate, which closes the formed cell housing at one end.

Thereby, a battery module is also realized, which is reduced in cost in terms of its manufacture due to the minimized number of components.

The invention also relates to a battery with at least one battery module according to the above-described embodiment variant of the invention.

The method for manufacturing the battery module of the above-described first embodiment variant of the invention is characterized by the following steps:

a) providing a cell base plate which integrally has a plurality of cell housings configured in a cup shape,

b) equipping the battery cell housing with a respective at least one battery cell coil, and

c) the cell housing is closed by one or more common cover elements.

The method for manufacturing the battery module of the above-described second embodiment variant of the invention is characterized by the following steps:

a) a substrate of a battery cell is provided,

b) providing an extruded profile which integrally forms a plurality of battery cell housings,

c) the formed cell housing is closed at one end by means of a cell substrate,

d) equipping the formed battery cell housing with a respective at least one battery cell coil, and

e) at the other end, the cell housing is closed by one or more common cover elements.

Drawings

The invention is explained in detail below on the basis of embodiments which are schematically shown in the drawing. The invention is not limited to these embodiments, however, but encompasses all designs defined by the claims. Wherein:

fig. 1 shows very schematically a vehicle equipped with an electric vehicle battery or a high-voltage battery, which has at least one battery module of the type according to the invention,

figure 2 shows an exploded view of a battery module according to a first advantageous embodiment variant of the invention,

figure 3 shows a first alternative embodiment of the battery module according to figure 2,

figure 4 shows a second alternative embodiment of the battery module according to figure 2,

figure 5 shows a third alternative embodiment of the battery module according to figure 2,

figure 6 shows a fourth alternative embodiment of the battery module according to figure 2,

figure 7 shows a fifth alternative embodiment of the battery module according to figure 2,

fig. 8 shows an exploded view of a battery module according to a second advantageous embodiment variant of the invention, an

Fig. 9 shows an alternative embodiment of the battery module according to fig. 8.

List of reference numerals

1 vehicle

2 electric motor

3 Battery

4 Battery pack case

5 Battery module

6 Battery cell

7 Battery cell substrate

8 Battery cell casing

9 Battery cell coil

10 tube

11 free space

12 cover element

12' cover element

13 electrode connection

14 electrode connection

15 cavity

16 blocks of material

17 extrusion profile

18 channel structure

19 temperature-regulating medium connection

20 a tempering medium coupling.

Detailed Description

First, fig. 1 shows a vehicle 1, currently a passenger car, with an electric motor 2 as a drive motor and a battery pack 3. According to this exemplary embodiment, the vehicle 1 is thus a purely electric vehicle 1 with an electric vehicle battery or high-voltage battery 3. The invention also comprises, in particular, so-called hybrid vehicles which, in addition to one or more electric motors 2, also have an internal combustion engine (not shown). In general, the battery 3 has at least one, preferably two or more battery modules 5 arranged in a battery housing 4 and electrically coupled to one another, the battery modules 5 each comprising a plurality of battery cells 6, in particular lithium-ion battery cells, electrically coupled to one another in parallel and/or in series.

In this connection, fig. 2 shows a first advantageous embodiment variant of a battery module 5 constructed according to the invention in an exploded view, as a result of which a method for producing the battery module is also obtained. Furthermore, the battery module 5 has a battery cell substrate 7 with a plurality of battery cells 6 arranged on the battery cell substrate 7. The battery cells 6 each have a cell housing 8 and at least one cell coil 9 arranged in the cell housing. The cell substrate 7 may form a separate member or be formed by the case bottom of the pack case 4. The cell housing 8 is formed in one piece with the cell base plate 7, for example according to a 3D printing method or in a known casting method from an electrically conductive, in particular metallic material, for example aluminum or an aluminum alloy.

The cell housings 8 are arranged parallel to one another and are each formed by a tube 10 which extends from the cell base plate 7 perpendicularly to the cell base plate 7. The cell base plate 7 accordingly closes the tube 10 at one end, whereby a cup-shaped cell housing 8 is formed. According to this exemplary embodiment, the cup-shaped cell housing 8 has a circular cross section and, together with a corresponding cylindrical cell coil 9 which can be inserted into this cross section, forms a so-called circular cell.

Currently, the battery cell housings 8 are arranged spaced apart from one another. In contrast, the cell housings 8 can also be arranged relative to one another in such a way that their adjacent wall sections come into contact or transition into one another in one piece, as a result of which a particularly stable composite structure (not shown) is formed. As already explained above, the free spaces 11 which are present between adjacent tubular cell housings 8 can be used, for example, for tempering the battery cells 6, by allowing a tempering fluid to flow through said free spaces 11.

Each cell housing 8 has associated with it a cover element 12 which completely closes the cell housing 8 equipped with the cell coil 9. If, as already indicated above, the cell housing 8 together with the cell substrate 7 is made of an electrically conductive, in particular metallic material, for example aluminum or an aluminum alloy, this preferably represents an electrode, generally a negative electrode. The first electrode connection 13 in this respect is arranged at the battery cell base plate 7. The cover elements 12, which are designed in an electrically insulated manner from the respective battery cell housing 8, each have a second electrode connection 14 with a positive electrode. Thereby, a parallel circuit of the battery cells 6 is preferably obtained. The

electrode connections

13,14 serve, in particular, to electrically integrate the battery module 5 into a modular composite of two or more battery modules 5 of the battery 3 or to make contact therewith.

According to the embodiment shown in fig. 3, which is an alternative to the above-described embodiment of the battery module 5, the plurality of cover elements 12 is replaced by a single, common cover element 12'. The single cover element 12' accordingly has a second electrode connection 14 with a positive electrode. Corresponding to this embodiment, the single cover element 12 'can serve as a cover element 12' which is directly associated with the relevant battery module 5. In contrast, a single, common cover element 12 'can also be formed by the cover element 12' of the battery 3 or its battery housing 4, and furthermore two or more battery modules 5 of the battery 3 can also be associated (not illustrated).

The invention furthermore comprises an alternative embodiment of a battery module 5 constructed according to the invention, which is not illustrated, in which, by means of

separate electrode connections

13,14, two electrodes are provided by a cover element 12 of the battery module 5 or of the battery pack 3 having at least one battery module 5, which completely encloses the respective battery cell housing 8 together with the battery cell coil 9, or by a common cover element 12' of the battery module 5 or of the battery pack 3 having at least one battery module 5, which completely encloses the battery cell housing 8 together with the battery cell coil 9. Thereby, the parallel connection and/or the series connection of the battery cells 6 are achieved.

Furthermore, it is also possible and the invention likewise accordingly provides that the cover element 12 closing the cell base plate 7 together with the cell housing 8 and/or the cell housing 8 or the common cover element 12' is designed to be electrically non-conductive, for example formed from plastic or fiber-reinforced plastic, but has an electrically conductive structure, not shown, for electrically coupling the formed battery cells 6 to the cell connections and coupling elements, which is already known from the known embodiment, for example, from DE 102008059967 a 1. Here, too, not only the parallel connection but also the series connection of the battery cells 6 is realized.

The embodiment of the battery module 5 according to fig. 4 and 5 differs from the embodiment described above only in that the cell housing 8 has a polygonal, in the present case rectangular, cross section, in which cell housing 8 the flat wound cell coils 9 are respectively arranged. In this case, a respective cover element 12 (see fig. 4) is or can be associated with each cell housing 8 or a single, common cover element 12' (fig. 5) is or can be associated with all cell housings 8.

The embodiment of the battery module 5 according to fig. 6 and 7 differs from the embodiment described above in that the tubular cell housing 8, which is only exemplary with a circular cross section, is formed in each case by a cavity 15 in a common, compact material block 16 of the cell base plate 7. That is, the battery cell base plate 7 is dimensioned such that the cavity 15 for representing the battery cell housing 8 and the cup-shaped housing accommodating the battery cell coil 9 is constructed merely by, for example, machining the material block 16, for example by drilling or milling. So-called blind holes are correspondingly formed. In contrast, such a compact battery cell substrate 7 can also be manufactured according to a 3D printing method or according to a casting process. However, the invention is not limited to the exemplary illustrated round battery cells with a round cross section, but also encompasses round battery cells with an inverted round, for example cylindrical, cross section or prismatic battery cells 6, i.e. battery cells 6 with a polygonal cross section. In this case, a respective cover element 12 (see fig. 6) is or can be associated with each cell housing 8 or a single, common cover element 12' (fig. 7) is or can be associated with all cell housings 9.

Fig. 8 and 9 show a second advantageous embodiment variant of a battery module 5 constructed according to the invention in an exploded view, as a result of which a method for its production is also obtained. The illustrated battery module 5 differs from the embodiment described above essentially in that all the cell housings 8 of a plurality of battery cells 6 are formed in one piece by a single extruded profile 17 by forming a plurality of elongated cavities 15 arranged parallel to one another in a row according to an extrusion method for receiving the cell coils 9 in the extruded profile 17. The extruded profiles 17 or the cell housings 8 formed by them and connected to one another in one piece are closed at one end by means of a cell base plate 7 which is produced separately and joined to the extruded profiles 17. The engagement means can be in the form of a force fit, a form fit and/or a material fit. At the other end, each cell housing 8 is associated or associable with a respective cover element 12 (see fig. 8) or all cell housings 8 are associated or associable with a unique, common cover element 12' (fig. 9).

Common to all the above-described exemplary embodiments is furthermore that the battery cell base plate 7 has at least one channel structure 18 through which a medium can flow, which can be used to regulate the temperature of the battery cells 6 of the associated battery module 5, the channel structure 18 having at least one first temperature regulating medium connection (temperature regulating medium connection) 19 as a forward part and at least one second temperature regulating medium connection 20 as a reverse part. The at least one channel structure 18 is preferably integrated into a temperature control, in particular cooling, system of the vehicle 1.

In a preferred embodiment of the invention, which is not illustrated, the channel structure 18 is integrated into the cell substrate 7. According to a further embodiment, which is not shown, the channel structure 18 is formed by a channel structure 18 which is produced separately, joined or can be joined to the cell substrate 7, with a meandering course, for example.

Claims

1. A battery module (5) having a cell substrate (7) and a plurality of battery cells (6) arranged on the cell substrate (7), wherein the battery cells (6) each have a cell housing (8) and at least one cell coil (9) arranged in the cell housing (8), characterized in that the cell housings (8) of the plurality of battery cells (6) are each configured cup-shaped and in one piece with the cell substrate (7), wherein a free space (11) is provided between adjacent cell housings (8) for the passage of a tempering fluid through the free space (11) for tempering the battery cells (6).

2. The battery module (5) according to claim 1, characterized in that the battery cell housing (8) has been constructed with a circular or polygonal cross section.

3. The battery module (5) according to claim 2, characterized in that each cell housing (8) is formed by a tube (10) which extends from the cell base plate (7) perpendicularly to the cell base plate (7) and is closed at one end by the cell base plate, the tube having a circular or polygonal cross section.

4. The battery module (5) according to claim 2, characterized in that the cell housings (8) with a circular or polygonal cross section are each formed by a cup-shaped cavity (15) in a common, compact material block (16) of the cell base plates (7).

5. The battery module (5) according to any one of claims 1 to 4, characterized in that the battery cell base plate (7) together with the battery cell housing (8) is configured to be electrically conductive and has one electrode of the battery module (5) by means of an electrode connection (13), conversely by an electrode connection (14) of the battery module (5) or of a battery pack (3) having at least one battery module (5), each of which encloses the relevant battery cell housing (8) together with a battery cell coil (9) and is configured to be electrically insulated relative to the battery cell housing (8), or by an electrode connection (14) of a common cover element (12') of a battery module (5) or of a battery pack (3) having at least one battery module (5), which encloses a battery cell housing (8) and is configured to be insulated relative to the battery cell housing (8) ) Another electrode is provided.

6. The battery module (5) according to any one of claims 1 to 4, characterized in that two electrodes are provided by means of separate electrode connections (13,14) by one cover element (12) of the battery module (5) or of a battery pack (3) having at least one battery module (5), each of which encloses the associated cell housing (8) together with the cell coil (9), or by a common cover element (12') of the battery module (5) or of a battery pack (3) having at least one battery module (5), which encloses the cell housing (8).

7. The battery module (5) according to any one of claims 1 to 4, characterized in that the cover element (12) closing the cell base plate (7) together with the cell housing (8) and/or the cell housing (8) or the common cover element (12') is configured to be electrically non-conductive, but with an electrically conductive structure for electrically coupling the battery cells (6) that have been formed.

8. The battery module (5) according to any one of claims 1 to 4, characterized in that at least the cell base plate (7) has at least one channel structure (18) through which a medium can be conducted for tempering the battery cells (6) of the battery module (5).

9. Battery module (5) having a cell base plate (7) and a plurality of battery cells (6) arranged on the cell base plate (7), wherein the battery cells (6) each have a cell housing (8) and at least one cell coil (9) arranged in the cell housing (8), characterized in that the cell housings (8) of the plurality of battery cells (6) are formed in one piece by an extruded profile (17), and the extruded profile (17) is connected or can be connected to a separately produced cell base plate (7), the cell base plate (7) closing the formed cell housing (8) at one end, wherein a free space (11) is provided between adjacent cell housings (8) for the passage of a tempering fluid through the free space (11), tempering the battery cell (6).

10. A battery (3) with at least one battery module (5) according to any one of claims 1 to 9.

11. A method for manufacturing a battery module (5) according to any of claims 1 to 8, characterized by the steps of:

a) providing a cell substrate (7) which has a plurality of cell housings (8) configured in a cup-shaped manner,

b) each of the battery cell housings (8) is provided with at least one battery cell coil (9), and

c) closing the cell housing (8) by means of one or more common cover elements (12,12'),

wherein a free space (11) is provided between adjacent cell housings (8) for the passage of a temperature control fluid through the free space (11) for temperature control of the battery cells (6).

12. A method for manufacturing a battery module (5) according to claim 10, characterized by the steps of:

a) providing a cell substrate (7),

b) providing an extruded profile (17) which forms a plurality of cell housings (8) in one piece,

c) closing the formed cell housing (8) at one end by means of the cell base plate (7),

d) each of the formed cell housings (8) is provided with at least one cell coil (9), and

e) closing the cell housing (8) at the other end by means of one or in each case common cover element (12,12'),