WO2024223229A1 - Device for connecting terminals of elementary cells - Google Patents

Abstract

The invention relates to a connection device (100) comprising: - a coupling element provided with a contact plate (300) and with a spring element (400), the coupling element being configured to be slidingly coupled with the terminals between an insertion position and a coupling position, the coupling position being a position in which the contact plate (300) bears, by the action of the spring element (400), via its first face, on the two contact faces, while the insertion position is a position that corresponds to the sliding engagement of the coupling element (200), by its engagement face, with the terminals; and - spacing means configured to keep the first face at a distance from the contact faces from the insertion position and over a main run when the coupling element (200) is coupled with the terminals.

Description

device for connecting terminals of elementary cells FIELD OF THE INVENTION

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 elementary cells of a battery block.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

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.

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.

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 connected to other elementary cells without having to also replace these other cells.

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 considered. However, this modular approach is not optimal and leaves vacant volumes, in particular between the modules. 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.

Thus, another approach can include the consideration of removable connection devices. This approach, which opens the way to the individual disassembly of each elementary cell, makes it possible to improve the compactness of battery blocks. However, the implementation of removable connection devices remains problematic. Indeed, the latter must be able to ensure sufficient electrical contact without their assembly and/or disassembly degrading the surface condition of the terminals.

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.

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

The aims of the invention are, at least in part, achieved by a connection device for connecting two adjacent elementary cells, each provided with an upper face on which a terminal rests, the two terminals being symmetrical with respect to a plane P, and each comprising a contact face defining a plane C perpendicular to the plane P, the connection device comprising:

- a coupling element provided with a contact plate and a spring element, the coupling element being configured to be coupled in sliding connection with the terminals, according to a coupling direction defined by the intersection of plane C with plane P, between an insertion position and a coupling position, the coupling position being a position for which the contact plate is supported under the action of the spring element, by one of its faces, called the first face, with the two contact faces, while the insertion position is a position which corresponds to the engagement of said coupling element, by one of its faces, called the engagement face, in sliding connection with the terminals;

- spacing means configured to, when coupling the coupling element with the terminals, maintain the first face at a distance from the contact faces from the insertion position and over a main stroke, and to allow contact between the first face and the contact faces as soon as the coupling element adopts the coupling position.

According to one embodiment, said connection device also comprises an insulating housing, said insulating housing comprising a main part and two side walls, each side wall extending laterally to the main part and ending with a contact edge, the side walls being intended to laterally frame the two terminals when coupling the coupling element with said terminals.

According to one embodiment, said connection device also comprises two bases each provided with a sliding section, each of the sliding sections being intended to be arranged, respectively, on one and the other of the upper faces, symmetrically with respect to the plane P and so as to laterally frame the two terminals, each sliding section comprising a face called a sliding face against which a contact edge is intended to slide during the coupling of the coupling element to the terminals.

According to one embodiment, the contact edges and the sliding faces are shaped to form the spacing means.

According to one embodiment, the spacing means comprise bumps and depressions formed, respectively, on the contact edges and on the sliding faces, the bumps and depressions being configured so that each bump is housed in a depression when the coupling element is in the coupling position.

According to one embodiment, each contact edge comprises two of the bumps, while each sliding face comprises two of the depressions.

According to one embodiment, the sliding connection between the coupling element and the terminals is ensured by the spring element.

According to one embodiment, the spring element, formed from a sheet metal, comprises a main section linked to the contact plate by a face, called the second face, of said contact plate and opposite the first face, the spring element also comprises two lateral sections arranged laterally to the main section and curved in a convergent manner in order to cooperate in sliding connection with recesses formed on the sides of the terminals.

According to one embodiment, each lateral section is discontinuous in a direction parallel to the edge of the main section from which the lateral section considered extends.

According to one embodiment, each side section comprises at least one divergent tab configured to allow the separation of the side section considered during engagement of the coupling element.

According to one embodiment, the contact plate comprises bosses projecting relative to the first face.

Other characteristics and advantages of the invention will emerge from the detailed description which follows with reference to the appended figures in which:

There 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;

There is a schematic representation of two adjacent elementary cells of a battery pack, the two cells being represented in a perspective view;

There is a schematic representation of a connection device in accordance with the principles set out in the present invention and according to a perspective view allowing the first face of the contact plate to be observed, in particular the connection device illustrated in comprises, in addition to the coupling element, an insulating housing allowing the handling of the connection device;

There is a schematic representation of the coupling element of the connection device of the according to a perspective view and allowing the first face of the contact plate to be observed;

There is a schematic representation of the contact plate of the coupling element of the , the contact plate is notably represented according to a perspective view allowing the first face to be observed;

There is a schematic representation of the spring element of the coupling element of the , the spring element is notably represented in a perspective view by a face of the main section intended to be opposite a second face of the contact plate and opposite the first face;

There is a schematic representation of two terminals of two adjacent elementary cells, in particular the terminals are represented in a perspective view by their contact face;

There is a representation of a terminal of the in isolation;

There is a schematic representation of an insulation housing capable of being implemented within the framework of the present invention, in particular, the insulation housing is shown in a perspective view;

There is a schematic representation of a connecting device connected, in its coupling position, with the two terminals of two adjacent elementary cells.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a connection device for connecting two adjacent cells, each provided with an upper face on which a terminal rests, the two terminals being symmetrical with respect to a plane P, and each comprising a contact face defining a plane C perpendicular to the plane P.

The connection device comprises, in this regard, a coupling element provided with a contact plate and a spring element. The coupling element is in particular configured to be coupled in sliding connection with the two terminals, according to a coupling direction defined by the intersection of the plane C with the plane P, between an insertion position and a coupling position. In particular, the coupling position is a position for which the contact plate is supported under the action of the spring element, by one of its faces, called the first face, with the two contact faces, while the insertion position is a position which corresponds to the engagement of said coupling element, by one of its faces, called the engagement face, in sliding connection with the terminals.

The connection device further comprises spacing means configured to, when coupling the coupling element with the terminals, maintain the first face at a distance from the contact faces from the insertion position and over a main stroke, and to allow contact between the first face and the contact faces as soon as the coupling element adopts the coupling position.

Thus, the connection device as previously described does not involve any welding or other means of permanent fixing which would prevent its disassembly.

Furthermore, the spring element, by exerting a bearing force against the contact plate, ensures sufficient electrical contact between said contact plate and the contact faces.

Finally, the coupling mode between the coupling element and the terminals, insofar as the first face remains at a distance on the main stroke of the contact faces, makes it possible to preserve the surface condition of said contact faces and thus ensure good quality of the electrical contact.

There is an illustration of two elementary cells 10a and 10b of a battery pack 10. Each elementary cell 10a and 10b is of prismatic shape and more particularly of rectangular parallelepiped 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 implemented 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 adjacent elementary cells 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.

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 can 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.

In the remainder of this statement, reference will be made to the connection of two terminals 11a and 12b of two adjacent elementary cells. Each of the terminals 11a and 12b considered is in particular formed on a face, called the upper face, of an elementary cell. It is understood that the upper faces of two adjacent elementary cells are coplanar. It is also understood that the two terminals 11a and 12b are also symmetrical to each other with respect to the plane P. More particularly, the two terminals intended to be electrically connected each comprise a contact face 13a and 13b. In this regard, the two contact faces 13a and 13b are coplanar and define a plane C perpendicular to the plane P.

To the , an example of a connection device 100 in accordance with the present invention can be seen.

In particular, the connection device 100 is intended to connect the two terminals 11a and 12b of the two adjacent elementary cells 10a and 10b.

In particular, the connection device 100 comprises a coupling element 200 (illustrated in ).

The coupling element 200 (illustrated in ) comprises in particular a contact plate 300 and a spring element 400.

The coupling element 200 is notably configured to be coupled in sliding connection with the two terminals 11a and 12b according to a coupling direction defined by the intersection of the plane C and the plane P.

More particularly, the coupling element 200 is configured to adopt, by sliding along the slide connection, one or the other of an insertion position and a coupling position.

In this regard, the coupling position is a position for which the contact plate 300 is in contact by one of its faces, called first face 301, against the two contact faces 13a and 13b.

Furthermore, the insertion position is a position which corresponds to the engagement of said coupling element, by one of its faces, called insertion face 210, in sliding connection with the two terminals 11a and 12b.

Furthermore, the spring element 400 is configured to exert a force against the contact plate 300 when the coupling element 200 is in the coupling position.

In particular, this force is exerted so as to impose a support of the contact plate 300, by its first face 301, against the contact faces 13a and 13b.

It is understood that the sliding connection considered in the present statement is of the maintained type. In other words, the sliding connection considered in the present invention can withstand forces in directions other than the coupling direction without risk of disengagement.

Contact plate 300 ( ), generally flat, can be formed from a sheet metal plate for example by stamping, and comprise two essentially parallel faces called, respectively, first face 301 and second face 302.

Furthermore, and as illustrated in the and to the , the contact plate 300 is perpendicular to the insertion face 210.

According to an advantageous embodiment, the contact plate 300 may have an imprint inscribed in a rectangle. More particularly, the contact plate 300 may comprise a central section 303, of generally rectangular shape, and lateral tabs 304 which extend on either side of the central section 303. The present invention is however not limited to a contact plate as described in relation to the .

In a particularly advantageous manner, the contact plate 300 may comprise bosses 305 projecting relative to the first face 301. More particularly, these bosses 305 may be formed on the lateral tabs 304. The bosses 305 formed on tabs independent of each other make it possible to ensure better electrical contact with the contact faces 13a and 13b.

Still advantageously, and without limiting the invention to this single aspect, the sliding connection between the coupling element 200 and the terminals 11a and 12b can be ensured by the spring element 400.

Thus, and still by way of example, the spring element 400 can be formed from a sheet metal (illustrated in ). More particularly, the spring element 400 may comprise a main section 401, for example of rectangular shape. The main section 401 comprises two essentially parallel faces and called, respectively, support face 402 and mounting face 403. In particular, and as illustrated in , the spring element 400 is mechanically secured to the contact plate 300. In this regard, the spring element 400 can be in contact with the second face of the contact plate 300 via its support face 402.

According to this example, the spring element 400 also comprises two side sections 404. More particularly, one and the other of the two side sections 404 extend from, respectively, a first side edge and a second side edge of the main section 401 and opposite one another.

The two side sections 404 are in particular curved inwardly towards each other on the side of the support face 401.

In particular, the side sections 404 may be configured to cooperate in a maintained sliding connection mode with recesses or grooves formed on a first lateral flank and a second lateral flank, respectively, of the terminal 11a and the terminal 12b.

It is understood that the first lateral flank and the second lateral flank are opposite and symmetrical to each other with respect to the plane P. It is further understood that the first lateral flank and the second lateral flank do not face each other.

So, the represents the two terminals 11a and 12b according to a perspective view by their contact face 13a and 13b. In particular, and without this having a limiting character, each terminal 11a and 12b comprises, according to the coupling direction, a first pad 11a1, 12b1 and a second pad 11a2 and 12b2. In particular, each first pad and each second pad comprises a pedestal 14, an intermediate section 15 and an upper plate 16 ( ). Advantageously, the first pad and the second pad of a given terminal may comprise a common pedestal 14.

Furthermore, the intermediate section 15 may have, in a direction normal to the plane P, a dimension smaller than that of the upper plate 16 in the same direction so as to form a recess on at least one of the lateral flanks of the first pad and the second pad.

This arrangement in particular allows the spring element 400 to be engaged via its lateral sections 404 with the upper plate(s) of each of the terminals 11a and 12b.

According to a particular embodiment, the lateral sections 404 may be discontinuous in a direction parallel to the edge of the main section from which the lateral section considered extends. In particular, each lateral section may comprise a plurality of curved spring tabs 404a (figures 6). This latter configuration is all the more advantageous since it makes it possible to separate the points of force exerted by the spring element engaged with the upper plates.

Advantageously, each lateral section comprises at least one divergent tab 405. The at least one divergent lateral tab is in particular configured to allow the spacing of the lateral section during engagement of the coupling element configured to allow the spacing of the lateral section considered during engagement of the coupling element in sliding connection with the terminals.

The connection device 100 may comprise an insulation housing 500 ( ). In particular, the insulation housing may be configured to allow manipulation of the coupling element 200. In this regard, the insulation housing 500 may comprise an electrically insulating material, for example a plastic material.

Thus, the insulation housing 500 may comprise a main part 501 and two side walls 502. More particularly, each side wall 502 extends laterally to the main part 501 and ends with a contact edge 503. In particular, the side walls 502 are intended to laterally frame the two terminals when coupling the coupling element 200 with said terminals 11a and 12b.

The insulation housing 500 may also comprise a bottom 505 opposite the insertion face 210, and connecting the main part 501 and the two side walls 502.

The assembly of the insulation housing 500 with the coupling element 200 is performed so that the spring element is interposed between the contact plate and the main part of the spring element. It is further understood that according to this configuration the side walls 502 frame the coupling element 200. The insulation housing 500 may also comprise means for holding the coupling element allowing the mechanical assembly between said insulation housing and said coupling element 200. In particular, the holding means may comprise snap-fastening means.

The connection device may also comprise two bases 600 each provided with a sliding section 601 ( ). In particular, each of the sliding sections 601 may be intended to be arranged, respectively, on one and the other of the upper faces, symmetrically with respect to the plane P and so as to laterally frame the two terminals 11a and 12b.

Each sliding section 601 comprises a face called sliding face 601a against which a contact edge 503 of the insulation housing 500 is intended to slide during the coupling of the coupling element to the terminals 11a and 12b.

The sliding faces 601 are advantageously flat and parallel to plane C.

Advantageously, each base can form a frame surrounding the terminal with which it is associated.

The connection device 100 according to the present invention also comprises spacing means configured to, when coupling the coupling element 200 with the terminals, keep the first face 301 at a distance from the contact faces from the insertion position and on a main stroke, and to allow contact between the first face 301 and the contact faces as soon as the coupling element adopts the coupling position. It is understood that the main stroke corresponds to the sliding of the coupling element from the insertion position and towards the coupling position.

Consideration of the spacing means thus makes it possible to preserve the surface condition of the contact faces, and consequently, to limit the degradation of the electrical contact between the contact plate and the contact faces.

According to an advantageous embodiment, the contact edges 503 and the sliding faces 601a are shaped to form the spacing means.

In particular, and by way of example, the spacing means may comprise bumps and depressions formed, respectively, on the contact edges 503 and on the sliding faces 601a. In this regard, the bumps 504 and the depressions 602 are configured so that each bump is housed in a depression when the coupling element is in the coupling position ( ).

In operation, the coupling element is engaged by its insertion face against the terminals (as opposed to the upper plates). The divergent tabs allow during this engagement a separation of the lateral sections of the spring element so that the latter can be engaged in sliding connection with the terminals.

The engagement is then followed by a sliding of the coupling element 200 from the insertion position to the coupling position. On the first stroke, the bosses 504 slide on flat parts of the sliding faces, and thus keep the first face at a distance from the contact faces. At the end of the stroke, the bosses 504 encounter the recesses 602, and fit into said recesses, thus allowing a coming together, more particularly a contact, between the first face and the contact faces.

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 (11)

Connection device (100) for connecting two adjacent elementary cells, each provided with an upper face on which a terminal rests, the two terminals (11a, 12b) being symmetrical with respect to a plane P, and each comprising a contact face defining a plane C perpendicular to the plane P, the connection device (100) comprising:
- a coupling element (200) provided with a contact plate (300) and a spring element (400), the coupling element (200) being configured to be coupled in sliding connection with the terminals (11a, 12b), according to a coupling direction defined by the intersection of the plane C with the plane P, between an insertion position and a coupling position, the coupling position being a position for which the contact plate (300) is supported under the action of the spring element (400), by one of its faces, called the first face (301), with the two contact faces (13a, 13b), while the insertion position is a position which corresponds to the engagement of said coupling element (200), by one of its faces, called the engagement face, in sliding connection with the terminals (11a, 12b);
- spacing means configured to, when coupling the coupling element (200) with the terminals (11a, 12b), maintain the first face (301) at a distance from the contact faces (13a, 13b) from the insertion position and on a main stroke, and to allow contact between the first face (301) and the contact faces (13a, 13b) as soon as the coupling element (200) adopts the coupling position. A connection device (100) according to claim 1, wherein said connection device (100) also comprises an insulating housing (500), said insulating housing (500) comprising a main part (501) and two side walls, each side wall (502) extending laterally to the main part (501) and ending in a contact edge (503), the side walls being intended to laterally frame the two terminals (11a, 12b) when coupling the coupling element (200) with said terminals (11a, 12b). Connection device (100) according to claim 2, wherein said connection device (100) also comprises two bases (600) each provided with a sliding section (601), each of the sliding sections being intended to be arranged, respectively, on one and the other of the upper faces, symmetrically with respect to the plane P and so as to laterally frame the two terminals (11a, 12b), each sliding section (601) comprising a face called a sliding face against which a contact edge (503) is intended to slide during the coupling of the coupling element (200) the terminals (11a, 12b). A connection device (100) according to claim 3, wherein the contact edges and the sliding faces (601a) are shaped to form the spacing means. A connection device (100) according to claim 3 or 4, wherein the spacing means comprise bumps (504) and recesses (602) formed, respectively, on the contact edges and on the sliding faces (601a), the bumps (504) and recesses (602) being configured so that each bump is housed in a recess (602) when the coupling element (200) is in the coupling position. A connection device (100) according to claim 5, wherein each contact edge (503) comprises two of the bumps (504), while each sliding face comprises two of the recesses (602). Connection device (100) according to one of claims 1 to 6, in which the sliding connection between the coupling element (200) and the terminals (11a, 12b) is ensured by the spring element (400). Connection device (100) according to one of claims 1 to 7, in which the spring element (400), formed of a sheet metal, comprises a main section (401) linked to the contact plate (300) by a face, called the second face (302), of said contact plate (300) and opposite the first face (301), the spring element (400) also comprises two lateral sections arranged laterally to the main section (401) and curved in a convergent manner in order to cooperate in sliding connection with recesses formed on the sides of the terminals (11a, 12b). Connection device (100) according to claim 8, in which each lateral section is discontinuous in a direction parallel to the edge of the main section (401) from which the lateral section considered extends. A connection device (100) according to claim 8 or 9, wherein each side section comprises at least one divergent tab configured to allow the separation of the side section in question during engagement of the coupling element (200). Connection device (100) according to one of claims 1 to 10, in which the contact plate (300) comprises bosses (305) projecting relative to the first face (301).