Assembly for a rechargeable electric cell

Abstract

Assembly for a rechargeable electric cell. The assembly (100) for a rechargeable electric cell comprises: a cover (101); a terminal (102); a current collector (103), the cover (101) being arranged between the current collector (103) and the terminal (102); an electrically conductive rivet (104) passing through the cover (101) and providing: electrical continuity between the terminal (102) and the current collector (103); a riveted assembly of the terminal (102) and the current collector (103) with respect to the cover (101); said rivet (104) comprising a head (105) and a fastening end (106) housed within the terminal (102) below the surface of a face (107) of the terminal (102) opposite the cover (101).

Description

Assembly for rechargeable electric cell Technical field of the invention

[0001] The technical field of the invention relates to rechargeable electric cells, more particularly the invention relates to an assembly for a rechargeable electric cell, in particular prismatic. Prior art

[0002] A prismatic rechargeable electric cell is classically closed by an assembly comprising terminals, a cover on which the terminals are assembled, typically a positive terminal and a negative terminal, and current collectors each electrically connected to one of the terminals by riveting.

[0003] More specifically, for each terminal and current collector pair to be assembled to the cover, a rivet is inserted through the current collector of that pair and the cover. During riveting, this rivet passes completely through the terminal of said pair before pushing one of its ends against an external face of the terminal to ensure a tightening force that pulls the terminal and current collector of the corresponding pair towards each other between a flange of the rivet and the pushed-out end of the rivet.

[0004] Although this solution is functional, it has a major drawback related to thermal expansion between the rivet material and the terminal material, for example respectively copper or aluminium when the terminal is aluminium.

[0005] Thermal expansion can occur during the operation of the rechargeable prismatic electrical cell contained within a battery, and under certain conditions the airtight seal of the rechargeable prismatic electrical cell may be temporarily breached at the interface between the rivet and the connection terminal to which the rivet is riveted. If the airtight seal is breached, this can: • cause a leakage of electrolyte contained in the prismatic rechargeable electric cell from the inside of the prismatic rechargeable electric cell to the outside of the prismatic rechargeable electric cell; • cause contamination of the prismatic rechargeable electric cell via an exchange from outside the prismatic rechargeable electric cell to inside the prismatic rechargeable electric cell; • induce instability of electrical connections, i.e. a loss of electrical connection between the terminal with one or more electrodes of the prismatic rechargeable electrical cell connected to the current collector itself electrically connected to the terminal by the rivet.

[0006] Therefore, there is a need to make the assembly of a terminal and current collector to the cover more robust. Object of the invention

[0007] The invention relates to a robust assembly for a rechargeable electric cell.

[0008] For this purpose, it relates to a rechargeable electric cell assembly, said rechargeable electric cell assembly comprising: • a cover intended to be mounted on an opening of a rechargeable electric cell casing; • a terminal; • a current collector, the cover being arranged between the current collector and the terminal; • an electrically conductive rivet passing through the lid and ensuring: o electrical continuity between the terminal and the current collector; o assembly by riveting the terminal and the current collector to the cover; said rivet comprising a head and a fixing end housed in the terminal under the surface of a face of the terminal opposite the cover, the head and the fixing end ensuring a clamping force so as to stress the terminal and the current collector towards the cover.

[0009] The rechargeable electric cell assembly may also include one or more of the following features.

[0010] According to a feature of the assembly for rechargeable electric cell, the rivet includes a body extending from the head and comprising, at a distance from the head, the fixing end, the head being arranged on a first side of the cover, the fixing end being arranged on a second side of the cover opposite to the first side and adopting the form of a collar.

[0011] According to a characteristic of the assembly for rechargeable electric cell, the rivet is configured so that, before riveting, the body has a length strictly less than a separation distance separating, before riveting, at least a part of the terminal face opposite the cover and a current collector face opposite the cover against which the rivet head is in contact after riveting of the rivet.

[0012] According to a feature of the assembly for rechargeable electric cell, the rivet body is configured so that, before riveting, the body has, opposite the head, a cavity delimiting a deformable end of the rivet.

[0013] According to a characteristic of the assembly for rechargeable electric cell, the cavity includes a bottom and a wall extending from this bottom at an angle between 91 degrees and 150 degrees.

[0014] According to a characteristic of the assembly for rechargeable electric cell, the rivet body is configured so that, before riveting, the body includes, opposite the head, a top formed by a circular edge or by a ring having an internal diameter and an external diameter, the internal diameter being strictly less than the external diameter.

[0015] According to a characteristic of the assembly for rechargeable electric cell, the cavity comprises a bottom, a wall extending from this bottom and a flank extending from the wall, the wall being vertical with respect to the bottom and the flank being diverging from the wall so that the flank and the wall form an angle with each other, strictly greater than 180 degrees and less than or equal to 269 degrees and preferably less than or equal to 240 degrees.

[0016] According to a characteristic of the assembly for rechargeable electric cell, the cavity has a depth of between 30% and 75% of a terminal height directly below a rivet penetration region in the terminal.

[0017] According to a characteristic of the rechargeable electric cell assembly, the charging station includes: • a recess opposite the lid; • at least one projection extending from the bottom of the recess and having a top arranged in the recess; said at least one projection being obtained by local deformation of the terminal during the formation of the fixing end.

[0018] The invention also relates to a method of manufacturing an assembly for a rechargeable electric cell as described, the manufacturing method comprising at least the following steps: a) placing the terminal on the side of a first face of the cover; b) placing the current collector on the side of a second face of the cover opposite to the first face of the cover; c) providing the rivet comprising a deformable end intended to form the fixing end; d) assemble the terminal and current collector to the cover by riveting using the rivet; step d) comprising successively: • a step of inserting the deformable end of the rivet through the current collector; • a step of inserting the deformable end of the rivet through the cover; • a rivet penetration step into the terminal causing deformation of the deformable end of the rivet to form the rivet fixing end.

[0019] The manufacturing process may also include one or more of the following features.

[0020] According to a feature of the manufacturing process, step d) includes a cooperation step of a support element with the terminal allowing to constrain, during the rivet penetration step in the terminal, the deformation of the deformable end of the rivet.

[0021] According to a feature of the manufacturing process, step c) is such that the rivet comprises a head and a body extending from the head, the body comprising the distal deformable end of the head, and step d) comprises, during the rivet penetration step into the terminal, a relative approach between the rivet head and the bearing element.

[0022] According to a feature of the manufacturing process, the support element is a punch comprising a cavity and the rivet penetration step into the terminal induces a displacement of material from the terminal into the cavity of the punch configured to limit said displacement of material from the terminal in order to constrain the deformation of the deformable end according to a predetermined displacement without causing penetration of the terminal.

[0023] According to a feature of the manufacturing process, the punch comprises a first punching part and a second punching part surrounding the first punching part, the first and second punching parts being connected to each other by a surface of the support element delimiting the cavity of the punch so that said cavity of the punch has an annular shape.

[0024] According to a feature of the manufacturing process, the bollard includes a recess with a bottom and the bearing element includes at least a portion inserted into the recess throughout the rivet penetration step into the bollard.

[0025] According to a feature of the manufacturing process, throughout the rivet penetration stage in the terminal, the punch cavity is included in the recess.

[0026] The invention also relates to a rechargeable electric cell comprising: • a case; • electrodes arranged in the housing; • an electrolyte arranged in the casing; • a rechargeable electric cell assembly as described, mounted in the housing, whose current collector is electrically connected to at least one of the electrodes.

[0027] Other features and benefits may emerge from the detailed description that follows. Brief description of the drawings

[0028] The invention will be better understood upon reading the detailed description that follows, given only as a non-limiting example and made with reference to the attached drawings listed below.

[0029] Figure 1 schematically represents a cross-sectional view of an assembly for a rechargeable electric cell according to a particular embodiment of the invention.

[0030] Figure 2 schematically represents a cross-sectional view of an embodiment of a rechargeable electric cell comprising said assembly for rechargeable electric cell.

[0031] Figure 3 schematically represents a cross-sectional view of a rivet according to one embodiment of the invention.

[0032] Figure 4 schematically represents a cross-sectional view of the rivet according to another embodiment of the invention.

[0033] Figure 5 schematically represents a cross-sectional view of the rivet according to another embodiment of the invention.

[0034] Figure 6 schematically represents a cross-sectional view of the rivet according to another embodiment of the invention.

[0035] Figure 7 shows a partial cross-sectional view of a step in a manufacturing process for the assembly for a rechargeable electric cell.

[0036] Figure 8 shows a partial cross-sectional view of another stage in the manufacturing process of the assembly for a rechargeable electric cell.

[0037] Figure 9 shows a partial cross-sectional view of another stage in the manufacturing process of the rechargeable electric cell assembly.

[0038] Figure 10 schematically represents a cross-sectional view of a variant of a support element used during the manufacturing process.

[0039] In these figures, the same references are used to designate the same elements. The elements represented in the different figures are not necessarily drawn to scale in order to facilitate understanding of the figures. Detailed description

[0040] In this description, "between two values" means a range of values ​​including said two values.

[0041] The invention relates to an assembly 100 for a 1000 rechargeable electric cell. In particular, Figure 1 shows a specific embodiment of this assembly 100 for a 1000 rechargeable electric cell, and Figure 2 shows this assembly 100 within the 1000 rechargeable electric cell.

[0042] According to the invention, said assembly 100 for a 1000 rechargeable electric cell comprises: • a cover 101 intended to be mounted to an opening 1001 of a housing 1002 of the rechargeable electric cell 1000, for example by welding; • a terminal 102; • a current collector 103, the cover 101 being arranged between the current collector 103 and the terminal 102; • an electrically conductive rivet 104 passing through the cover 101 and ensuring: o electrical continuity between terminal 102 and current collector 103; o an assembly by riveting the terminal 102 and the current collector 103 relative to the cover 101.

[0043] In other words, terminal 102, cover 101 and current collector 103 are riveted / assembled by riveting using rivet 104.

[0044] The rivet 104 includes a head 105 and a fixing end 106 housed in the terminal 102 under the surface of a face 107 of the terminal 102 opposite the cover 101, i.e. so as to ensure a fixing of the rivet 104 to the terminal 102, without passing through / piercing the terminal 102, and so as to ensure their electrical connection. By "fixing end 106 housed under the surface of the face 107 of the terminal 102 opposite the cover 101", it is understood that the fixing end 106 is arranged in the terminal 102 between the cover 101 and the face 107 of the terminal 102 opposite the cover 101 such that the rivet 104 does not pass through the terminal 102. In other words, the fixing end 106 is housed in the thickness of the terminal 102 so that the terminal 102 is fixed to the rivet 104 without this rivet 104 passing through the terminal 102.

[0045] As illustrated in figures 1 and 2, the fixing end 106 is arranged opposite the head 105.

[0046] The head 105 and the fixing end 106 ensure a clamping force so as to stress the terminal 102 and the current collector 103 towards the cover 101, this making it possible in particular to maintain, on the one hand, the terminal 102 with respect to the cover 101 and, on the other hand, to maintain the current collector 103 with respect to the cover 101, preferably so that the terminal 102 and the current collector 103 each have no degree of freedom with respect to the cover 101.

[0047] Thus, there is preferentially, within the assembly 100 for rechargeable electric cell 1000, a clamping force between the terminal 102 and the current collector 103 which are stressed towards each other by the rivet 104.

[0048] As illustrated in figures 1 and 2, rivet 104 is a separate part from current collector 103.

[0049] The fact that the fastening end 106, typically a recessed end of the rivet 104, is housed within the thickness of the terminal 102, i.e., beneath the surface of the face 107 of the terminal 102 opposite the cover 101, avoids the presence of a hole opening into the terminal 102 through which the rivet would pass. This improves the airtight seal at the point of interaction between the terminal 102 and the rivet 104, since the latter does not pass through the terminal 102. Consequently, this allows: • to tend to avoid, at this level, a leakage of an electrolyte 1003 from inside the rechargeable electric cell 1000 to outside the rechargeable electric cell 1000; • to tend to avoid, at this level, contamination of the 1000 rechargeable electric cell via an exchange from outside the 1000 rechargeable electric cell to inside the 1000 rechargeable electric cell; • to tend to avoid, at this level, inducing instability of electrical connections between terminal 102 and rivet 104, i.e. inducing a loss of electrical connection of the terminal with one or more electrodes of the rechargeable electrical cell 1000 electrically connected to the current collector 103.

[0050] Terminal 102, also known as the connection terminal, is designed to form either a positive or negative terminal of the 1000 rechargeable battery cell. Terminal 102 is made of an electrically conductive material.

[0051] The current collector 103 is specifically designed to form a cathode collector or an anode collector. The current collector 103 is typically made of an electrically conductive material.

[0052] The 1000 rechargeable electric cell can store energy or release it depending on its state chosen from a state of charge (energy storage) or discharge (energy release).

[0053] Preferably, the rivet 104 comprises a body 108 extending from the head 105. The body 108 includes, at a distance from the head 105 and in particular distal to the head 105, the fastening end 106. The head 105 is arranged on a first side Cl of the cover 101. The fastening end 107 is arranged on a second side C2 of the cover 101 opposite the first side Cl of the cover 101. The fastening end 107 takes the form of a collar, in particular obtained by pushing out a deformable end 109 of the body 108 arranged opposite the head 105 (see in particular Figures 3 to 6 showing this deformable end 109). In other words, the collar is engaged in the material of the terminal 102.

[0054] With this particular arrangement, efficient retention of terminal 102 relative to cover 101 is ensured. Furthermore, rivet 104 does not require any additional welding to ensure a suitable electrical connection at terminal 102, which is achieved through the close contact between the flange and terminal 102. In fact, welding is undesirable because it represents an additional cost in the manufacturing of the rechargeable 1000 electric cell, it slows down the production rate due to an extra operation, and it can create a risk of leakage at the weld.

[0055] In particular, the collar is such that it adopts the shape of a hemmed outwards, i.e. whose end opposite to the rest of the body 108 is turned outwards from the rivet 104.

[0056] Body 108 is notably cylindrical.

[0057] In particular, the first side Cl of the cover 101 is turned / is intended to be turned outwards from the rechargeable electric cell 1000, i.e. in the opposite direction to the housing 1002.

[0058] In particular, the second side C2 of the cover 101 is turned / is intended to be turned towards the housing 1002, and more specifically towards the inside of the rechargeable electric cell 1000.

[0059] In particular, the end of the body 108, before riveting, adopts the shape of the deformable end 109 as illustrated for example in figures 3 to 6.

[0060] Various realizations of the rivet 104 before riveting are now described, for example in its configurations as seen in figures 3 to 6. Each of these configurations has an impact on how the fixing end 106 is formed. In other words, by "before riveting", reference is made to the shape of the rivet 104 before a riveting operation which allows the terminal 102 and the current collector 103 to be assembled with respect to the cover 101 by implementing in particular a deformation of the deformable end 109.

[0061] According to one embodiment, the rivet 104 can be configured so that, before riveting, the body 108 has a length Ll, also called height, strictly less than a separation distance DI separating, before riveting, at least a part of the face 107 of the terminal 102 opposite the cover 101 and a face 110 of the current collector 103 opposite the cover 101 against which the head 105 of the rivet 104 is in contact after riveting of the rivet 104.

[0062] This prevents any risk of puncturing terminal 102 during the riveting operation via rivet 104.

[0063] The length Ll is notably measured along an axis Al of extension of the body 108 from the head 105, this axis Al of extension being notably orthogonal with respect to the plane of the head 105.

[0064] At least a portion of the face 107 of the terminal 102 opposite the cover 101 is, in particular, aligned with a region of the terminal 102 from which the body 108 of the rivet 104 enters via its deformable end 109 during the riveting operation. Specifically, the cover 101 may include an opening 111 through which the body 108 of the rivet 104 passes; at least a portion of the face 107 of the terminal 102 opposite the cover 101 may then be aligned with this opening 111.

[0065] The separation distance DI corresponds to a distance measured before riveting when the current collector 103 and the terminal 102 are positioned relative to the cover 101 in the position they will occupy after riveting.

[0066] Advantageously, the body 108 of the rivet 104 can be configured so that, before riveting, the body 108 has / includes, opposite the head 105, a cavity 112 delimiting the deformable end 109 of the rivet 104.

[0067] The cavity 112 allows a preferred shape to be given to the body 108 to promote the penetration of the rivet 104 into the terminal 102 without this penetration being through and to facilitate the desired deformation of the deformable end 109.

[0068] The cavity 112 is in particular a bore made in the body 108 along the axis Al of extension.

[0069] According to a particular embodiment, the cavity 112 may include a bottom 113 and a wall 114 extending from this bottom 113 at an angle al between 91 degrees and 150 degrees, for example as can be seen in figures 4 and 5.

[0070] With such an angle al, the wall 114 diverges from the bottom 113, which allows it to deform in a desired way to obtain the fixing end 106.

[0071] In particular, in this case, cavity 112 can adopt a truncated conical shape, specifically a truncated conical imprint.

[0072] The angle al is of course measured on the side of the surface of rivet 104.

[0073] The body 108 of the rivet 104 can be configured so that, before riveting, the body 108 comprises / presents, opposite the head 105, a vertex 115 formed by an annular, and more particularly circular, edge (Figures 5 and 6) or by a ring (Figures 3 and 4) having an internal and an external diameter, the internal diameter being strictly smaller than the external diameter. The ring may have a flat surface, in particular orthogonal to the extension axis Al.

[0074] With such a summit 115, the fixing end 106 ensures, at the end of the riveting operation, its function efficiently and makes it possible in particular to obtain the aforementioned hemmed edge.

[0075] According to one embodiment, the cavity 112 may comprise the bottom 113, the wall 114 extending from this bottom 113, and a flank 116 extending from the wall 114, and in particular this flank 116 is connected to the apex 115. The wall 114 may be vertical with respect to the bottom 113 (i.e., the wall 114 may be at a right angle to the bottom 113), and the flank 116 may diverge from the wall 114 such that the flank 116 and the wall 114 form an angle α2 with each other, strictly greater than 180 degrees and less than or equal to 269 degrees, and preferably less than or equal to 240 degrees. Here, the apex 115 is preferably formed by an annular or circular edge. In particular, with respect to the verticality of the wall 114, the side 116 forms an angle with this verticality strictly greater than 0 degrees and less than or equal to 89 degrees and preferably strictly greater than 0 degrees and less than or equal to 60 degrees.

[0076] This ensures that the collar will form appropriately, particularly radially from the rest of the body 108 arranged between the collar and the head 105. According to this embodiment, the rivet 104 has a satisfactory penetration capacity into the terminal.

[0077] The angle a2 is of course measured between the side 116 and the wall 114 on the side of the surface of the rivet 104.

[0078] The wall 113 can here be defined according to a right circular cylinder and the flank 116 can be defined by a truncated cone shape in particular of a truncated cone imprint.

[0079] The cavity 112 can have a depth PI between 30% and 75% of the height H1 of the terminal 102 at the level of a region of penetration of the rivet 104 into the terminal 102. This height H1 is in particular measured before penetration of the rivet 104 into the terminal 102 which can induce a deformation involving a modification of this height H1 as described below.

[0080] This depth for cavity 112 avoids drilling through the terminal (and therefore eliminates the need for additional welding to improve the seal). To enhance airtightness at the point where terminal 102 and rivet 104 interact, this results in: • to tend to avoid, at this level, the leakage of electrolyte 1003 from inside the rechargeable electric cell 1000 to outside the rechargeable electric cell 1000; • to tend to avoid, at this level, the contamination of the 1000 rechargeable electric cell via an exchange from outside the 1000 rechargeable electric cell to inside the 1000 rechargeable electric cell; • to tend to avoid, at this level, inducing instability in electrical connections as mentioned above.

[0081] According to one implementation, terminal 102 may include: • a recess 117 opposite the cover 101; • at least one projection 118 extending from a bottom 119 of the recess 117 and having a top 120 arranged in the recess 117, i.e. said at least one projection 118 does not protrude out of the recess 117. Said at least one projection 118 is obtained by local deformation of the terminal 102 during the formation of the fixing end 106, i.e. caused by the riveting operation of the rivet 104.

[0082] Thus, the bulk of the terminal 102 is controlled because said at least one projection 118 remains contained within the recess 117. This presents an advantage in terms of cost because it is not necessary to machine, for example by milling, the terminal 102 after the riveting operation to reduce its overall bulk.

[0083] The number of projections 118 can depend on the shape of the deformable end 109 of the rivet 104. For example, according to figures 3 to 6, the riveting operation leads to the formation of a single projection 118 at the bottom of the recess 117, this projection 118 being annular.

[0084] The height H1 is measured in particular between a face of the terminal 102 turned towards the cover 101 and the bottom 119 of the recess 117 without taking into account said at least one projection 118.

[0085] The assembly 100 for a 1000 rechargeable electric cell may include a sealing gasket 121 comprising at least one portion clamped between the cover 101 and the current collector 103, said sealing gasket 121 being able to be configured to: • electrically isolate rivet 104 from cover 101; and / or • seal the passage of rivet 104 through opening 111 in cover 101.

[0086] This allows for a satisfactory seal by preventing air from passing through opening 111.

[0087] Thus, the length of the body 108 will be adjusted in particular to take into account the different elements called the set of parts (in particular chosen from: the cover, the current collector and the sealing gasket 121) which the body 108 passes through before the body 108 enters the terminal 102 to ensure that the body 108 does not pass through the terminal 102.

[0088] As shown in Figures 1 and 2, the assembly 100 for the 1000 rechargeable electric cell can include two terminals attached to the cover 101 and each electrically connected by a rivet corresponding to a corresponding current collector.

[0089] Thus, in one embodiment, terminal 102 can be a positive terminal, the current collector 103 is then a cathode collector, and the rivet 104 securing their assembly by riveting forms a first rivet 104. The assembly 100 for a rechargeable electric cell 1000 can then include an anode collector 123, a negative terminal 124, with the cover 101 arranged between the negative terminal 124 and the anode collector 123. The assembly 100 then includes a second electrically conductive rivet 125 as described above. Everything that applies to the first rivet 104 in relation to the cathode collector 103 and the positive terminal 102 can be applied in the same way to the second rivet 125 in relation to the negative terminal 124 and the anode collector 123.

[0090] Thus, the second rivet 125 passes through the cover 101 and ensures: • electrical continuity between the negative terminal 124 and the anode collector 123; • an assembly by riveting the negative terminal 124 and the anode collector 123 relative to the cover 101; said second rivet 125 comprising a head 126 and a fixing end 127 housed in the negative terminal 124 under the surface of a face 128 of the negative terminal 124 opposite the cover 101, the head 126 and the fixing end 127 ensuring a clamping force so as to stress the negative terminal 124 and the anode collector 123 in the direction of the cover 101.

[0091] Thus, there is preferentially, within the assembly 100 for rechargeable electric cell 1000, a clamping force between the negative terminal 124 and the anode collector 123 which are stressed towards each other by the second rivet 125.

[0092] As illustrated in figures 1 and 2, the second rivet 125 is a separate part from the anode manifold 123.

[0093] Within the assembly 100 for a 1000 rechargeable electric cell, the fastening end 127 and the head 126 of the second rivet 125 can rivet a group of parts comprising successively the anode collector 123, the cover 101, and the negative terminal 124. Thus, a body 129 of the second rivet 125 can pass through at least the anode collector 123 and the cover 101 before its fastening end 127 engages with the negative terminal 124.

[0094] The group of parts may also include a seal 122 to contribute to the sealing of the rechargeable electric cell 1000. The seal 122 can then be mounted on the body 129 of the second rivet 125 and be in contact with the anode collector 123 on one side, and on the other side with a through hole 130 formed through the cover 101 and through which the body 129 of the second rivet 125 passes, as shown for example in Figure 2.

[0095] A manufacturing process for the assembly 100 for a rechargeable electric cell 1000 is now described, the various steps of which are illustrated by way of example in Figures 7 to 9. This manufacturing process includes at least the following steps: a) positioning the terminal 102 on the side of a first face 101a of the cover 101 (Figure 8); b) positioning the current collector 103 on the side of a second face 101b of the cover 101 opposite the first face of the cover 101 (Figure 8); c) providing the rivet 104 including the deformable end 109 intended to form the fixing end 106 (Figure 8); d) assembling the terminal 102 and the current collector 103 to the cover 101 by riveting using the rivet 104 (Figures 8 and 9).Of course the process can include a step of supplying a riveting station consisting of providing the terminal 102, the current collector 103 and the rivet 104 at the level of this riveting station to allow the implementation of steps a) to d) within this riveting station.

[0096] Step d) comprises successively (see in particular the arrow Fl in figure 7): • a step of inserting the deformable end 109 of the rivet 104 through the current collector 103, preferably through a through hole 131 formed beforehand in the current collector 103; • a step of inserting the deformable end 109 of the rivet 104 through the cover 101, preferably through the opening 111 previously formed in the cover 101; • a step of penetration of the rivet 104 into the terminal 102 causing a deformation of the deformable end 109 of the rivet 104 to form the fixing end 106 of the rivet 104.

[0097] Step d) is illustrated in particular by the transition from figure 7 to figure 8 and then to figure 9.

[0098] With such a deformation of rivet 104, its fixing end 106 remains contained within the thickness of terminal 102, thus improving the airtightness at the cooperation between terminal 102 and rivet 104, since the latter does not pass through terminal 102.

[0099] Of course, at the end of step d) the tightening force described above is ensured.

[0100] For example, the planned rivet 108 is of the type illustrated in figures 3 to 7 in its state before riveting.

[0101] Advantageously, step d) can include a cooperation step of a support element 200 with the terminal 102 allowing to constrain, during the penetration step of the rivet 104 into the terminal 102, the deformation of the deformable end 109 of the rivet 104, i.e. in order to form the fixing end 106 of the rivet 104.

[0102] The support element 200 is an appropriate solution to prevent rivet 104 from piercing terminal 102 and in particular to promote the formation of the collar adopting the hemmed shape.

[0103] This cooperation step can consist of a stress on the support element 200 according to a support force F2 of the support element 200 against the terminal 102 as for example visible in figure 8 where the rivet 104 penetrates the terminal 102.

[0104] In particular, the support element 200 belongs to the aforementioned riveting station.

[0105] In particular, the support element 200 applies a bearing force on the terminal 102 throughout the penetration step of the rivet 104 into the terminal 102.

[0106] Step c) may be such that the rivet 104 comprises the head 105 and the body 108 extending from the head 101, the body 108 comprising the deformable end 109 arranged opposite the head 105, and step d) comprises, during the penetration step of the rivet 104 into the terminal 102, a relative approach between the head 105 of the rivet 104 and the support element 200.

[0107] Thus, the head 105 of the rivet 104 can approach the cover 101 as the penetration step of the rivet 104 into the terminal 102 progresses until the assembly of the terminal 102 to the cover 101 is locked, in particular via the appropriate clamping force between the head 105 and the fixing end 106 resulting from the deformation of the deformable end 109.

[0108] Advantageously, the support element 200 can be a punch comprising a cavity 204 and the penetration step of the rivet 104 into the terminal 102 induces a displacement of material of the terminal 102 in said cavity 204 configured to limit said displacement of material of the terminal 102 in order to constrain the deformation of the deformable end 109 according to a predetermined displacement without causing penetration of the terminal 102.

[0109] The displacement of the deformable end 109 is then constrained in an appropriate manner, in particular so as to limit the shape of the projection 118 (figure 9), in figure 8 the penetration of the rivet 104 begins to form what will become the projection 118.

[0110] The punch may be such that it comprises a first punching portion 201 and a second punching portion 202, in particular annular, surrounding the first punching portion 201. The first and second punching portions 201, 203 are connected by a surface 203 of the support element 200, which defines the cavity 204 of the punch, such that said cavity 204, referred to as the annular cavity 204, has an annular shape. In this case, the manufacturing process may be such that the step of driving the rivet 104 into the terminal 102 induces a displacement of material from the terminal 102 into the annular cavity 204. This annular cavity 204 is then configured to limit said displacement of material from the terminal 102 in order to constrain the deformation of the deformable end 109 according to a predetermined displacement without causing penetration of the terminal 102. [yes] The displacement of the deformable end 109 is then constrained appropriately in particular because the first part 201 of punching tends to oppose a deformation of the rivet towards the inside of its cavity 112: the formation of the hem towards the outside is thus favoured.

[0112] The first part 201 of punching may include a punching end in the form of a point or a flat surface.

[0113] The second part 202 of punching may include an annular edge or an annular surface having an internal diameter and an external diameter strictly greater than the internal diameter.

[0114] In particular, figures 7 to 9 show one punching end in the form of a point and the second part 202 of the punching end with an annular edge.

[0115] Alternatively, as shown in Figure 10, the punch can be such that its cavity 204 is delimited by an imprint of a portion of a sphere, for example, a spherical cap.

[0116] According to a particular implementation of the manufacturing process, the terminal 102 may include the recess 117 equipped with the bottom 119 and the support element 200 includes at least a portion inserted into the recess 117, and in particular bearing on the terminal 102 at the bottom of the recess 117, throughout the penetration step of the rivet 104 into the terminal 102.

[0117] The recess 117 serves in particular as a keying feature for the positioning of the support element 200, thus allowing repeatability of riveting for the mass production of assemblies for rechargeable electric cells.

[0118] According to one implementation of the manufacturing process, throughout the step of penetration of the rivet 104 into the terminal 102, the cavity 204 of the punch is included in the recess 117.

[0119] This makes it possible to constrain the displacement of material from the terminal 102 to the volume of the recess 117, thus avoiding an increase in the overall bulk volume of the terminal 102 defined as the volume of the terminal 102 plus the volume of the recess 117 before implementation of the rivet penetration step 104 into the terminal 102.

[0120] Advantageously, the 1000 rechargeable electric cell is a prismatic rechargeable electric cell.

[0121] The invention also relates to the 1000 rechargeable electric cell comprising: • the 1002 case; • electrodes 1004 arranged in housing 1002; • the electrolyte 1003 arranged in the casing 1002; • the assembly 100 for rechargeable electric cell 1000 mounted to the case 1002, for example by welding to the opening 1001 of the case 1002. The current collector 103 of the assembly 100 for rechargeable electric cell 1000 is electrically connected to at least one of the electrodes 1002.

[0122] Of course, if collector 103 is the cathode collector, then at least one of its electrodes is a cathode, for example, electrically connected to the cathode collector 103 via an electrically conductive tab 1005 of the rechargeable cell 1000. If the negative terminal 124 is present, the anode collector 123 is connected to at least one anode of the electrodes 1004, for example, via an electrically conductive tab 1006 of the rechargeable cell 1000.

[0123] The housing 1002 can be made of a hard and rigid material, for example a metallic material, the purpose of which is to protect the electrodes 1004.

[0124] In particular, the electrodes 1004 comprise at least one anode and at least one cathode. In this case, said at least one cathode is electrically connected to the cathode collector 103 and said at least one anode is electrically connected to the anode collector 123, notably via respective tabs 1005, 1006.

[0125] In fact, the 1004 electrodes can be integrated within a multilayer winding comprising successively a cathode, a first separator, an anode, and a second separator. This winding can be positioned in the casing of the rechargeable 1000 electric cell where the anode is electrically connected to the anode collector 123 and the cathode is electrically connected to the cathode collector 103. This is called electrode winding technology.

[0126] As an alternative to winding technology, a stacking technology can be used, for example, implemented by a stacking process consisting of cutting cathode and anode foils to the required size from a roll, then stacking them in layers, each consisting of a cathode foil, a separator, and an anode foil, with two adjacent stacked layers separated by a separator. The stacked layers can then be introduced into the housing 1002, and the cathode foils can be electrically connected to the cathode collector 103 and the anode foils to the anode collector 123.

[0127] Thus, in the context of the rechargeable electric cell 1000, the current collector 103 of the assembly 100 for rechargeable electric cell 1000 can be electrically connected on the one hand to the terminal 102 via the rivet 104 and, on the other hand, to said at least one of the electrodes 1002, i.e. to the winding or the superposition of stacks.

[0128] The electrodes and separators are immersed in electrolyte 1003 which allows the passage of ions from one electrode to the other (anode and cathode pair) in both directions, depending on whether it is a matter of storing or transferring energy.

[0129] For example, rivet 104 can be made of / from aluminum, particularly in the ALI 0XX series and especially in AL1050. In this case, terminal 102 can be a positive terminal made of / from aluminum, for example in the AL30XX series and especially in AL3003. In this case, current collector 103 can be a cathode collector made of / from aluminum, for example in AL1050.

[0130] For example, rivet 104 can be copper-based, specifically in the C11XX copper series, for example Cl 100, or in nickel-plated CuOL (Copper Oxygen Light). In this case, terminal 102 can be a negative terminal made of aluminum, for example in the AL30XX aluminum series, particularly AL 3003. In this case, the current collector 103 can be an anode collector made of copper, for example Cl 100 or CuOL. This can also apply to the aforementioned second rivet 125, negative terminal 124, and anode collector 123.

[0131] The lid 101 can be made of / based on aluminium, for example in AL3003.

[0132] Of course, a person skilled in the art can add to the set 100 for cell 1000 of battery any part as needed to allow, for example, if necessary, electrical isolation between the terminal(s) (if necessary positive and / or negative) and the cover 101.

[0133] The present invention finds industrial application in the field of batteries, particularly for electric vehicles. A battery can comprise a plurality of 1000 rechargeable electrical cells.

[0134] An electric vehicle is defined as a vehicle comprising at least one motor to drive one or more of the wheels of the electric vehicle using a battery comprising 1000 rechargeable electric cells as described. Such a vehicle may be 100% electric or a hybrid vehicle also equipped with an internal combustion engine.

Claims

Demands 1. Assembly (100) for rechargeable electric cell (1000), said assembly (100) for rechargeable electric cell (1000) comprising: • a cover (101) intended to be mounted to an opening (1001) of a housing (1002) of the rechargeable electrical cell (1000); • a terminal (102); • a current collector (103), the cover (101) being arranged between the current collector (103) and the terminal (102); • an electrically conductive rivet (104) passing through the cover (101) and ensuring: o electrical continuity between the terminal (102) and the current collector (103); o an assembly by riveting the terminal (102) and the current collector (103) relative to the cover (101); said rivet (104) comprising a head (105) and a fixing end (106) housed in the terminal (102) under the surface of a face (107) of the terminal (102) opposite the cover (101), the head (105) and the fixing end (106) ensuring a clamping force so as to stress the terminal (102) and the current collector (103) in the direction of the cover (101).

2. Assembly (100) for rechargeable electric cell (1000) according to claim 1, in which the rivet (104) comprises a body (108) extending from the head (105) and comprising, at a distance from the head (105), the fixing end (106), the head (105) being arranged on a first side (Cl) of the cover (101), the fixing end (107) being arranged on a second side (C2) of the cover (101) opposite (Cl) to the first side and adopting the form of a collar.

3. Assembly (100) for rechargeable electric cell (1000) according to claim 2, in which the rivet (104) is configured so that, before riveting, the body (108) has a length (Ll) strictly less than a separation distance (Dl) separating, before riveting, at least a part of the face (107) of the terminal (102) opposite the cover and a face (110) of the current collector (103) opposite the cover (101) against which the head (105) of the rivet (104) is in contact after riveting of the rivet (104).

4. Assembly (100) for rechargeable electric cell (1000) according to any one of claims 2 to 3, wherein the body (108) of the rivet (104) is configured such that, before riveting, the body (108) has, opposite the head (105), a cavity (112) delimiting a deformable end (109) of the rivet (104).

5. Assembly (100) for a rechargeable electric cell (1000) according to claim 4, wherein the cavity (112) comprises a bottom (113) and a wall (114) extending from this bottom (113) at an angle (al) between 91 degrees and 150 degrees.

6. Assembly (100) for a rechargeable electric cell (1000) according to any one of claims 2 to 5, wherein the body (108) of the rivet (104) is configured such that, before riveting, the body (108) comprises, opposite the head (105), a peak (115) formed by a circular edge or by a ring having an internal diameter and an external diameter, the internal diameter being strictly less than the external diameter.

7. Assembly (100) for rechargeable electric cell (1000) according to claim 4, in which the cavity (112) comprises a bottom (113), a wall (114) extending from this bottom (113) and a side (116) extending from the wall (114), the wall (114) being vertical with respect to the bottom (113) and the side (116) being diverging from the wall (114) such that the side (116) and the wall (114) form an angle (a2) between them, strictly greater than 180 degrees and less than or equal to 269 degrees and preferably less than or equal to 240 degrees.

8. Assembly (100) for rechargeable electric cell (1000) according to any one of claims 4 to 7, in which the cavity (112) has a depth (PI) between 30% and 75% of a height (Hl) of the terminal (102) directly below a penetration region of the rivet (104) in the terminal (102).

9. Assembly (100) for a rechargeable electric cell (1000) according to any one of claims 1 to 8, wherein the terminal (102) comprises: • a recess (117) opposite the cover (101); • at least one projection (118) extending from a bottom (119) of the recess (117) and having a top (120) arranged in the recess (117); said at least one projection (118) being obtained by local deformation of the terminal (102) during the formation of the end (106) of attachment.

10. A method for manufacturing an assembly (100) for a rechargeable electric cell (1000) according to any one of claims 1 to 9, the manufacturing method comprising at least the following steps: a) arrange the terminal (102) on the side of a first face (101a) of the cover (101); b) arrange the current collector (103) on the side of a second face (101b) of the cover (101) opposite to the first face of the cover (101); c) provide the rivet (104) comprising a deformable end (109) intended to form the fixing end (106); d) assemble by riveting the terminal (102) and the current collector (103) to the cover (101) using rivet (104); step d) comprising successively: a step of inserting the deformable end (109) of the rivet (104) through the current collector (103);• a step of inserting the deformable end (109) of the rivet (104) through the cover (101); • a rivet penetration step (104) into the terminal (102) causing a deformation of the deformable end (109) of the rivet (104) to form the rivet (104) fixing end (106).

11. Manufacturing method according to claim 10, wherein step d) includes a cooperation step of a support element (200) with the terminal (102) allowing to constrain, during the penetration step of the rivet (104) into the terminal (102), the deformation of the deformable end (109) of the rivet (104).

12. A manufacturing method according to claim 11, wherein step c) is such that the rivet (104) comprises a head (105) and a body (108) extending from the head (105), the body (108) comprising the distal deformable end (109) of the head (105), and wherein step d) comprises, during the penetration step of the rivet (104) into the terminal (102), a relative approach between the head (105) of the rivet (104) and the support element (200).

13. A manufacturing method according to any one of claims 11 to 12, wherein the support element (200) is a punch comprising a cavity (204) and wherein the step of penetration of the rivet (104) into the terminal (102) induces a displacement of material from the terminal (102) into the cavity (204) of the punch configured to limit said displacement of material from the terminal (102) in order to constrain the deformation of the deformable end (109) according to a predetermined displacement without causing penetration of the terminal (102).

14. Manufacturing method according to claim 13, wherein the punch comprises a first punching part (201) and a second punching part (202) surrounding the first punching part (201), the first and second punching parts (201, 202) being connected to each other by a surface (203) of the support element (200) delimiting the cavity (204) of the punch so that said cavity (204) of the punch has an annular shape.

15. A manufacturing method according to any one of claims 11 to 14 wherein the terminal (102) comprises a recess (117) provided with a bottom (119) and wherein the support element (200) comprises at least a portion inserted into the recess (117) throughout the rivet (104) penetration step into the terminal (102).

16. A manufacturing method according to any one of claims 13 to 14 and claim 15, wherein, throughout the rivet penetration step (104) into the terminal (102), the cavity (204) of the punch is included in the recess (117).

17. Rechargeable electric cell (1000) comprising: unboitier (1002); electrodes (1004) arranged in the housing (1002); • an electrolyte (1003) arranged in the housing (1002); • an assembly (100) for a rechargeable electric cell according to any one of claims 1 to 9, mounted in the housing (1002), the current collector (103) of which is electrically connected to at least one of the electrodes (1002).

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