Connection device for the electrical connection of two terminals of two elementary cells of a battery pack

Abstract

The invention relates to a device for connecting two elementary cells each provided with a terminal, the two terminals being arranged symmetrically with respect to the plane P, the connection device comprising: - a coupling member (20) made of a conductive material; - two main assemblies (22), each main assembly (22) comprising a clip, the clip comprising two wings and a base, the two main assemblies are each intended to be fixed to a terminal, the two main assemblies, when they are each fixed to a terminal, are arranged to allow the insertion of the coupling member (20) between one and the other of the at least one clip in a coupling direction defined by the direction of extension of the bases of said clips, the clips also being configured to clamp the wings of the at least one clip against the coupling member (20).

Description

Connection device for the electrical connection of two terminals of two elementary cells of a battery pack FIELD OF THE INVENTION

[0001] The present invention relates to the field of batteries, and more particularly to the field of batteries for electric vehicles. In particular, the present invention relates to a device for connecting battery cells. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0002] Batteries for powering electric vehicles generally comprise a plurality of elementary cells electrically connected to each other in parallel or in series. The electrical connections are notably implemented by means of connection devices. More particularly, each connection device is configured to electrically connect two electrical terminals of two adjacent elementary cells.

[0003] In this regard, the illustrates the implementation of a connection device 5, known from the state of the art, for electrically connecting an assembly of two elementary cells 1 and 2 of generally parallelepiped shape. The connection device 5 comprises two contact sections called, respectively, first section 6 and second section 7 connected by a central section 8. The elementary cells 1 and 2 comprise, respectively, a first terminal 3 and a second terminal 4 electrically connected by the connection device 5. More particularly, the electrical connection is ensured by soldering the connection device 5 on both the first terminal 3 and the second terminal 4.

[0004] However, the consideration of maintaining the connection device 5 by means of welds is not satisfactory. Indeed, the latter do not allow easy disassembly, without damage, of the elementary cells. In particular, according to this approach, it cannot be envisaged to replace, individually, a damaged elementary cell and connected to other elementary cells without having to also replace these other cells.

[0005] In order to overcome, at least partially, this drawback, a battery pack generally comprises a set of modules each formed by elementary cells connected together with the connection means 5 described above. Thus, the detection of a damaged elementary cell within a given module will only require the replacement of the module in question. However, this modular approach leaves vacant volumes.

[0006] However, the consideration of all-electric motor vehicles requires an increase in the available energy density, and consequently an increase in the space available for the elementary cells.

[0007] An aim of the present invention is therefore to propose a device for connecting elementary cells which can be easily dismantled without damaging said cells.

[0008] Another aim of the present invention is to propose a device for connecting elementary cells opening the way to the integration of a greater number of elementary cells for a given volume. BRIEF DESCRIPTION OF THE INVENTION

[0009] The aims of the present invention are, at least in part, achieved by a device for connecting two elementary cells of a battery block, adjacent by a plane P, and each provided with a terminal, the two terminals being arranged symmetrically to each other with respect to the plane P, the connection device comprising:

[0010] - a coupling member made of a conductive material;

[0011] - two main assemblies, each main assembly comprising at least one clip, the at least one clip of each main assembly comprising two wings and a base from which each wing extends towards a side called free and opposite the base, the two main assemblies are each intended to be fixed to a terminal by placing the free sides of their respective clips opposite each other and symmetrically with respect to the plane P, the two main assemblies, when they are each fixed to a terminal, are also arranged to allow the insertion of the coupling member between one and the other of the at least one clips in a direction, called the coupling direction, defined by the direction of extension of the bases of said clips, the at least one clip being further configured to ensure the clamping, by spring effect, of the wings of the at least one clips against the coupling member.

[0012] According to one embodiment, each main assembly is configured to be attached to a terminal via a wing of its at least one clip, called an attachment wing.

[0013] According to one embodiment, the at least one clip of each main assembly comprises a connection clip and a spring clip, the spring clip being mounted covering the connection clip and exerting a force, by spring effect, opposing the separation of the wings of the connection clip, the attachment wing being a wing of the connection clip.

[0014] According to one embodiment, the wing of the spring clip, called the lower wing, covering the attachment wing is perforated to allow direct contact and fixing of said attachment wing on a section of a terminal forming a pedestal.

[0015] According to one embodiment, the other wing of the connection clip, called the contact wing, comprises tabs, called connection tabs, capable of forming as many points of contact with the coupling member.

[0016] According to one embodiment, the other wing of the spring clip, called the upper wing, comprises tabs, called spring tabs, and intended to cooperate with the connection tabs in order to exert contact with the coupling member.

[0017] According to one embodiment, the coupling member comprises bosses intended to be in contact with the connection tabs.

[0018] According to one embodiment, said connection device comprises an insulating housing intended to cover, at least partially, the main assemblies when they are fixed to a terminal.

[0019] According to one embodiment, the insulation box comprises a two-part base covering at least laterally the main assemblies when the latter are fixed to the terminals, and a cover.

[0020] According to one embodiment, the base comprises a slot allowing the insertion of the coupling member.

[0021] According to one embodiment, the coupling member comprises an overmolded gripping means.

[0022] According to one embodiment, the coupling member is flat and essentially rectangular in shape.

[0023] The invention also relates to a battery block provided with at least two elementary cells, adjacent by a plane P, and each provided with a terminal, the two terminals being arranged symmetrically to each other with respect to the plane P and electrically connected to at least one of the connection device according to the present invention.

[0024] Other characteristics and advantages of the invention will emerge from the detailed description of a device for connecting two elementary cells of a battery block which will follow with reference to the appended figures in which:

[0025] Illustrates the implementation of a connection device, known from the state of the art, for the electrical connection of two elementary cells of a battery block;

[0026] This is a schematic representation of two adjacent elementary cells of a battery pack, the two cells being represented in a perspective view;

[0027] This is a schematic representation according to an exploded view of all the elements forming the connection device according to the present invention, the figure also represents the terminals of two adjacent elementary cells;

[0028] This is a schematic representation of a flat, rectangular-shaped coupling member capable of being implemented within the framework of the present invention, in particular, this is a representation of the coupling member according to a perspective view making it possible to observe the upper face of said coupling member;

[0029] This is a schematic representation of two connection clips that can be implemented within the framework of the present invention, the two connection clips being shown facing each other and in a perspective view;

[0030] This is a schematic representation of two spring clips that can be implemented within the framework of the present invention, the two spring clips being shown facing each other and in a perspective view;

[0031] This is a schematic representation of a main assembly formed of a connecting clip and a spring clip, in particular the main assembly is shown in perspective view;

[0032] This is a representation of a battery pack which comprises a plurality of elementary cells 101 arranged against each other, the elementary cells being connected two-by-two by means of connection devices according to the present invention;

[0033] This is a schematic representation of an insulation box consisting of an insulation base and a cover. DETAILED DESCRIPTION OF THE INVENTION

[0034] The present invention relates to a connection device for connecting two elementary cells of a battery pack, adjacent by a plane P, and each provided with a terminal. The two terminals are in particular arranged symmetrically with respect to the plane P.

[0035] The connecting device comprises a coupling member made of a conductive material.

[0036] The connection device also includes two main assemblies.

[0037] In particular, each main assembly comprises at least one clip. The at least one clip of each main assembly comprises two wings and a base from which each wing extends towards a so-called free side opposite the base. Furthermore, the two main assemblies are each intended to be fixed to a terminal by placing the free sides of their respective clips opposite each other and symmetrically with respect to the plane P.

[0038] The two main assemblies, when each is fixed to a terminal, are also arranged to allow the insertion of the coupling member between one and the other of the at least one clips in a direction, called the coupling direction, defined by the direction of extension of the bases of said clips, the at least one clip being further configured to ensure the clamping, by spring effect, of the wings of the at least one clips against the coupling member.

[0039] This is an illustration of two elementary cells 10a and 10b of a battery pack 10. Each elementary cell 10a and 10b is prismatic in shape and more particularly parallelepipedal in shape. In particular, the two elementary cells 10a and 10b are part of a set of elementary cells stacked against each other in a Y direction, and forming a battery pack capable of being used for powering a motor vehicle. The two elementary cells 10a and 10b are in particular adjacent to each other. More particularly, a lateral face of the elementary cell 10a is opposite a lateral face of the elementary cell 10b. It is understood that these two lateral faces are perpendicular to the Y direction.By convention, two elementary cells adjacent along a plane P means that one of the elementary cells has a lateral face opposite a lateral face of the other elementary cell, the two lateral faces opposite each other having the plane P as a median plane.

[0040] Each elementary cell 10a and 10b comprises two terminals. More particularly, the elementary cell 10a comprises a positive terminal 11a and a negative terminal 12a. Equivalently, the elementary cell 10b also comprises a positive terminal 11b and a negative terminal 12b. The two terminals of an elementary cell may each be arranged on the same face or on two opposite faces of said elementary cell. It is understood, without it being necessary to specify it, that the two terminals of two elementary cells to be connected are each arranged on a face of the elementary cell to which they belong, the two faces considered being coplanar.

[0041] The connection device according to the present invention is configured to electrically connect a terminal of the elementary cell 10a with a terminal of the elementary cell 10b. In this respect, it may be an electrical connection in parallel or in series. The remainder of the description will be limited to a series connection without, however, limiting the scope of the present invention to this aspect alone.

[0042] The connection device 1 according to the present invention is configured to connect the positive terminal 11a with the negative terminal 12b. The positive terminal 11a and the negative terminal 12b are arranged symmetrically with respect to the plane P.

[0043] The connection device 1 according to the present invention is shown in an exploded view at. This figure also shows the two terminals of two adjacent elementary cells. In particular, each of these two terminals may comprise a through hole 14 (the latter may possibly be tapped). This hole 14 may in particular make it possible to fix, for example by means of a screw, said terminal on an elementary cell. Alternatively, each terminal may be without a hole. According to this latter alternative, the elementary cell may be fixed to a terminal by crimping. Furthermore, each terminal 11a and 12b may comprise one or more pedestals 13a projecting relative to its free face.

[0044] The connection device according to the present invention comprises a coupling member 20 made of a conductive material. In particular, without necessarily limiting the scope of the present invention to these aspects alone, the coupling member 20 may be flat and generally rectangular in shape.

[0045] In this regard, the is a schematic representation of a flat and rectangular coupling member 20. In particular, the coupling member 20 comprises two parallel faces called respectively, upper face 20a and lower face 20b, and connected by a contour 20c.

[0046] Furthermore, the coupling member 20 may comprise bosses 21, in particular obtained by stamping, projecting relative to the upper face 20a.

[0047] The coupling member 20 may also comprise an overmolded gripping means 26. In particular, the gripping means 26 may be made of an electrically insulating material, for example plastic.

[0048] The connection device comprises two main assemblies 22. In particular, each main assembly 22 comprises at least one clip 30. More particularly, the at least one clip 30 of each main assembly comprises two wings and a base from which each wing extends towards a so-called free side opposite the base. The two main assemblies are each intended to be fixed to a terminal by placing the free sides of their respective clips opposite each other and symmetrically with respect to the plane P.

[0049] The two main assemblies 22, when each is fixed to a terminal, are also arranged to allow the insertion of the coupling member between one and the other of the at least one clips in a direction, called the coupling direction, defined by the direction of extension of the bases of said clips 30, the at least one clip being further configured to ensure the clamping, by spring effect, of the wings of the at least one clips against the coupling member.

[0050] According to a particularly advantageous embodiment, the at least one clip 30 of each main assembly 20 comprises a connection clip 30a and a spring clip 30b.

[0051] In particular, the represents two connection clips 30a capable of being implemented within the framework of the present invention. In particular, the connection clip 30a comprises two wings, called connection wings 31a and 32a, connected to each other by a base, called connection base 33a and which extend from said connection base 33a each towards their free edge, called connection edge 35a.

[0052] Equivalently, the represents two spring clips 30b capable of being implemented within the framework of the present invention. In particular, the spring clip 30b comprises two wings, called spring wings 31b, 32b, connected to each other by a base, called spring base 33b and which extend from said spring base 33b each towards their free edge, called spring edge 35b.

[0053] As illustrated in , the spring clip 30b and the connection clip 30a of a main assembly 22 are arranged so that the two spring wings 31b and 32b are arranged on either side of the connection clip 30a. More particularly, the spring wings 31b and 32b each bear against one of the connection wings 31a and 31b and exert a spring force on each of said connection wings 31, 32 tending to tighten them against each other.

[0054] Furthermore, each main assembly is configured to be attached to a terminal via a wing of its at least one clip, called an attachment wing. In particular, the attachment wing is configured to be attached to the at least one pedestal of the terminal in question.

[0055] Thus, since the main assembly is formed of the spring clip and the connecting clip, the attachment wing corresponds to the connecting wing 32a.

[0056] Furthermore, the spring wing 32b, called the lower wing, and covering the attachment wing, is perforated to allow direct contact and fixing of said attachment wing on a section of a terminal forming a pedestal 13a.

[0057] Advantageously, the connection wing 31a, opposite the attachment wing and called the contact wing, comprises tabs, called connection tabs 34a, capable of forming as many points of contact with the coupling member 20. In this respect, the bosses 21 are arranged so that each one is in contact with a connection tab 34a when the coupling member 20 is inserted between one and the other of the connection clips of the two main assemblies.

[0058] Still advantageously, the spring wing 31b, opposite the lower wing and called the upper wing, covering the contact wing, comprises tabs, called spring tabs 34b, and intended to cooperate with the connection tabs 34a in order to exert contact with the coupling member.

[0059] Consideration of the spring tabs 34b and the connection tabs 34a makes it possible to decouple the contact points between the coupling member and the connection clip from each other. This configuration makes it possible to compensate for any misalignment of the coupling member when it is inserted between the connection clips.

[0060] This configuration also makes it possible to compensate for a slight displacement of the elementary cells.

[0061] Advantageously, the connection device according to the present invention may comprise an insulating housing intended to cover, at least partially, the main assemblies when they are fixed to a terminal. In particular, the insulating housing 40 may comprise an insulating base 40 and a cover (). The insulating base laterally covers the two main assemblies, while the cover closes the insulating housing. The insulating base 40 may comprise two parts 40a each associated and fixed to a terminal.

[0062] The insulation base 40 advantageously comprises a slot allowing the insertion of the coupling member 20.

[0063] The implementation of the connection device according to the present invention is illustrated in.

[0064] In particular, it represents a battery pack 100 which comprises a plurality of elementary cells 101 arranged against each other.

[0065] In this figure, each terminal 11a, 12b is associated with a part 40a of the insulation base and is fixed to an elementary cell 101. A main assembly 22 is also fixed to each terminal 11a, 12b. The attachment of an assembly may involve, for example, the welding of the attachment wing 32a to a pedestal 14.

[0066] The arrangement of the elementary cells against each other, and the positioning of the main assemblies according to the terms previously described allows the insertion of the coupling member according to the coupling direction. It is understood that the coupling direction is included in the plane P and perpendicular to the direction Y of stacking of the elementary cells 101.

[0067] The invention also relates to a battery block provided with at least two elementary cells, adjacent by a plane P, and each provided with a terminal, the two terminals being arranged symmetrically to each other with respect to the plane P and electrically connected to at least one of the connection device according to the present invention.

[0068] Of course, the invention is not limited to the embodiments described and variant embodiments can be made without departing from the scope of the invention as defined by the claims.

Claims

Connection device (1) for two elementary cells of a battery block, adjacent by a plane P, and each provided with a terminal, the two terminals being arranged symmetrically to each other with respect to the plane P, the connection device (1) comprising: - a coupling member (20) made of a conductive material; - two main assemblies (22), each main assembly (22) comprising at least one clip, the at least one clip of each main assembly (22) comprising two wings and a base from which each wing extends towards a so-called free side and opposite the base, the two main assemblies are each intended to be fixed to a terminal by placing the free sides of their respective clips opposite each other and symmetrically with respect to the plane P, the two main assemblies, when they are each fixed to a terminal,are also arranged to allow the insertion of the coupling member (20) between one and the other of the at least one clips in a direction, called the coupling direction, defined by the direction of extension of the bases of said clips, the at least one clip being further configured to ensure the clamping, by spring effect, of the wings of the at least one clips against the coupling member (20), each main assembly (22) is configured to be fixed to a terminal via a wing of its at least one clip, called the attachment wing, the at least one clip of each main assembly (22) comprises a connection clip (30a) and a spring clip (30b), the spring clip (30b) being mounted to cover the connection clip (30a) and exerts a force, by spring effect, opposing the separation of the wings (31a, 32a) of the connection clip, the attachment wing being a wing of the connection clip (32a)., Connection device (1) according to claim 1, in which the wing of the spring clip, called the lower wing (32b), covering the attachment wing is perforated to allow direct contact and fixing of said attachment wing on a section of a terminal forming a pedestal (14). Connection device (1) according to claim 1 or 2, in which the other wing of the connection clip, called contact wing, comprises tabs, called connection tabs (34a), capable of forming as many points of contact with the coupling member (20). Connection device (1) according to claim 2 and claim 3, in which the other wing of the spring clip, called the upper wing, comprises tabs, called spring tabs (34b), and intended to cooperate with the connection tabs in order to exert contact with the coupling member (20). Connection device (1) according to claim 3 or 4, wherein the coupling member (20) comprises bosses (21) intended to be in contact with the connection tabs (34a). Connection device (1) according to one of claims 1 to 4, wherein said connection device (1) comprises an insulating housing intended to cover, at least partially, the main assemblies when they are fixed to a terminal. A connection device (1) according to claim 6, wherein the insulation housing comprises a two-part insulation base at least laterally covering the main assemblies when the latter are fixed to the terminals, and a cover. A connection device (1) according to claim 7, wherein the base comprises a slot allowing the insertion of the coupling member (20). Connection device (1) according to one of claims 1 to 8, in which the coupling member (20) comprises an overmolded gripping means. Connection device (1) according to one of claims 1 to 9, in which the coupling member (20) is flat and of essentially rectangular shape. Battery block provided with at least two elementary cells, adjacent by a plane P, and each provided with a terminal, the two terminals being arranged symmetrically to each other with respect to the plane P and electrically connected to at least the connection device (1) according to one of claims 1 to 10.

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