Cover for connecting energy storage assemblies

Abstract

The invention relates to a cover for covering a tubular element of a first electrical energy storage assembly (20), said cover comprising a covering wall (50). The cover is characterized in that it comprises a radially extending electroconductive tongue (60, 70) comprising a contact face (71) intended to come into contact with a second adjacent storage assembly in order to electrically connect the two storage assemblies.

Claims

1. A cover intended to cap a tubular element of a first electrical energy storage assembly, the cover comprising a covering wall and at least one side wall essentially normal to the covering wall, wherein the cover comprises an electrically conductive radial tongue arranged on said at least one side wall, said tongue extending radially on its entire length from said side wall, said radial tongue having a contact face located at a free end of the radial tongue, essentially normal to the covering wall and of a concave shape, said contact face being intended to come into contact and to match with the cover or a tubular element of a second adjacent storage assembly to connect the two storage assemblies electrically together.

2. The cover according to claim 1 also comprising a peripheral skirt extending over the periphery of the covering wall, the radial tongue being arranged on the peripheral skirt.

3. The cover according to claim 1 forming a disc comprising the covering wall, the radial tongue being arranged on a side wall of the disc.

4. The cover according to claim 1, wherein the ends of the radial tongue in a direction normal to the covering wall are located between the ends of the remainder of the cover in this direction.

5. The cover according to claim 4, wherein the ends of the radial tongue in at least one other direction along the plane of the covering wall are located between the ends of the covering wall in this direction.

6. An energy storage assembly comprising a tubular element having a side face and at least one cover intended to cap one of the ends of the tubular element, the cover comprising a covering wall intended to cover said end of the tubular element and at least one side wall essentially normal to the covering wall, the cover comprising an electrically conductive radial tongue arranged on said at least one side wall, said tongue extending radially on its entire length from said side wall, said radial tongue having a contact face located at a free end of the radial tongue, essentially normal to the covering wall and of a concave shape, said contact face being intended to come into contact and to match with the cover or a tubular element of a second adjacent storage assembly to connect the two storage assemblies electrically together.

7. The assembly according to claim 6, wherein the cover forms a disc comprising the covering wall, the radial tongue being arranged on a side wall of the disc, and is intended to be inserted in the tubular element, the tubular element comprising a cut-out whose shape matches the shape of the cross-section of the radial tongue in its side wall to allow the radial tongue to pass.

8. The assembly according to claim 6 wherein the cover comprises a peripheral skirt extending over the periphery of the covering wall, the radial tongue being arranged on the peripheral skirt, the peripheral skirt being intended to surround the side face of the tubular element.

9. A module comprising at least two electrical energy storage assemblies, wherein at least one of the assemblies is an assembly comprising a tubular element having a side face and at least one cover intended to cap one of the ends of the tubular element, the cover comprising a covering wall intended to cover said end of the tubular element and at least one side wall essentially normal to the covering wall, the cover comprising an electrically conductive radial tongue arranged on said at least one side wall, said tongue extending radially on its entire length from said side wall, said radial tongue having a contact face located at a free end of the radial tongue, essentially normal to the covering wall and of a concave shape, said contact face coming into contact, matching with and being secured with the cover or with the tubular element of a second adjacent storage assembly to connect the two storage assemblies electrically together, the or at least one of the radial tongues of said cover or covers forming a connecting body allowing the electrical connection of the two assemblies.

10. The module according to claim 9, wherein the storage assembly or assemblies are configured so that the connecting body extends between the two storage assemblies so that the height of each storage assembly connected to the connecting body is equal to the height of a storage assembly not connected to a connecting body.

11. The module according to claim 9 wherein the two storage assemblies comprise a tubular element having a side face and at least one cover intended to cap one of the ends of the tubular element, the cover comprising a covering wall intended to cover said end of the tubular element and at least one side wall essentially normal to the covering wall, the cover comprising an electrically conductive radial tongue arranged on said at least one side wall, said tongue extending radially on its entire length from said side wall, said radial tongue having a contact face located at a free end of the radial tongue, essentially normal to the covering wall and of a concave shape, said contact face coming into contact, matching with and being secured with the cover or with the tubular element of a second adjacent storage assembly to connect the two storage assemblies electrically together, and wherein the connecting body comprises two radial tongues each forming a portion of the connecting body, each radial tongue being in a single piece with a cover of each respective assembly, said radial tongues being positioned on the assemblies so that they are superimposed during the electrical connecting of said assemblies.

12. The module according to claim 11, wherein one of the radial tongues forming the connecting body is thicker than the other of the radial tongues forming the connecting body.

13. The module according to claim 11 wherein each portion of the connecting body is connected to the assembly from which it is separate, via welding.

14. The module according to claim 11, wherein each cover of each assembly forms a disc comprising the covering wall, the radial tongue being arranged on a side wall of the disc, and is intended to be inserted in the tubular element, the tubular element comprising a cut-out whose shape matches the shape of the cross-section of the radial tongue in its side wall to allows the radial tongue to pass.

15. The module according to claim 11, wherein each cover of each assembly comprises a peripheral skirt extending over the periphery of the covering wall, the radial tongue being arranged on the peripheral skirt, the peripheral skirt being intended to surround the side face of the tubular element.

16. The module according to claim 9, wherein the at least one cover of the assembly forms a disc comprising the covering wall, the radial tongue being arranged on a side wall of the disc, and is intended to be inserted in the tubular element, the tubular element comprising a cut-out whose shape matches the shape of the cross-section of the radial tongue in its side wall to allows the radial tongue to pass.

17. The module according to claim 9, wherein the at least one cover of the assembly comprises a peripheral skirt extending over the periphery of the covering wall, the radial tongue being arranged on the peripheral skirt, the peripheral skirt being intended to surround the side face of the tubular element.

18. A method for assembling a module comprising at least two electrical energy storage assemblies wherein at least one assembly comprises a tubular element having a side face and at least one cover intended to cap one of the ends of the tubular element, the cover comprising a covering wall intended to cover said end of the tubular element and at least one side wall essentially normal to the covering wall, the cover comprising an electrically conductive radial tongue arranged on said at least one side wall, said tongue extending radially on its entire length from said side wall, said radial tongue having a contact face located at a free end of the radial tongue, essentially normal to the covering wall and of a concave shape, said contact face being intended to come into contact and to match with the cover or with a tubular element of a second adjacent storage assembly to connect the two storage assemblies electrically together, the radial tongue such that its contact face comes into contact, matches with the cover or with the tubular element of the second adjacent storage assembly of a cover of the assembly forming the or one portion of a connecting body, wherein the method comprises positioning the radial tongue so as to join the two storage assemblies for the electrical connection thereof, and then a securing step of each contact face for the connecting thereof with the storage assembly from which it is separate.

19. The method according to claim 18, wherein the securing step is a welding step.

Description

PRESENTATION OF THE FIGURES

(1) Other characteristics, objects and advantages of the present invention will become further apparent from the following description which is solely illustrative and non-limiting and is to be read in connection with the appended drawings in which:

(2) FIG. 1 illustrates one embodiment of a prior art module;

(3) FIG. 2 illustrates an example of a module according to the invention;

(4) FIGS. 3 and 4 illustrate different examples of the positioning of a connecting body according to the invention;

(5) FIGS. 5 to 7 illustrate different embodiments of the connecting body according to the invention.

DESCRIPTION OF THE INVENTION

(6) A description will now be given of different embodiments of the module according to the invention with reference to the Figures. In these different Figures equivalent elements of the module carry the same reference numbers.

(7) As illustrated in FIG. 2, the module 1 comprises a casing 10 in which there are arranged at least two electrical energy storage assemblies 20. More specifically, the module comprises three storage assemblies arranged on several levels.

(8) The storage assemblies 20 are of globally cylindrical shape. In other variants not illustrated herein the storage assemblies may be of parallelepiped, cubic, oval, hexagonal shape without affecting the general principles of the invention.

(9) A first level 30 of the module comprises two storage assemblies 20 arranged side by side in a casing 10. A second level 40 of the module comprises a third energy storage assembly 20.

(10) The axes of revolution A-A of the storage assemblies 20 are parallel. In the embodiment illustrated in FIG. 2, the storage assemblies 20 are arranged so that their axes of revolution A-A are perpendicular to the lower wall 11 of the casing 10.

(11) Each storage assembly 20 comprises a tubular element 21 and a capacitor element (not illustrated) in the tubular element 21.

(12) The constituent material of the tubular element 21 may be electrically insulatinge.g. a plastican electrically conductive e.g. a metal such as aluminium, stainless steel etc.

(13) The tubular element 21 may be open at its two ends or it may have a bottom. In the embodiment illustrated FIG. 2, each tubular element 21 has two openings on is upper and lower faces.

(14) Each open face of the tubular element 21 is capped by a cover 50 electrically connected to the energy storage assembly 20 along the weld generating lines. The cover 50 is electrically conductive. The constituent material of the cover 50 is a metal for example such as aluminium, stainless steel, etc.

(15) Each cover 50 is composed of: a covering wall 51, 52, intended to cover the upper face 24 (respectively lower face 22) of its associated storage element 20, and a peripheral skirt 53, 54 intended partly to surround the side face 23 of the tubular element 21.

(16) Each cover 50 may or may not comprise a peripheral edge (such as the peripheral edge 132 illustrated in FIG. 1) extending outwardly parallel to the axis of revolution A-A of the storage assembly on its face opposite the peripheral skirt.

(17) The module also comprises three connecting bodies 60 which will be described in more detail further on.

(18) One particular aspect of the module of the invention is that the connecting body 60 and the covers 50 are connected via welding at the skirt 53, 54 of each cover 50. The welding technique may be transparent laser or edge-to-edge laser or preferably friction stir welding (FSW).

(19) By transparent laser welding is meant the fact that two superimposed parts are welded with an energy beam passing through one of the parts to be weldedeither through a thinned portion thereof if the part is thick or through the entire thickness if the part is thin.

(20) By edge-to-edge laser welding is meant the fact that two parts positioned edge to edge are welded using an energy beam that is not a through beam but is adjusted to the shape of the edges to be welded and positioned with precision at the interface of the edges to be welded.

(21) The invention such as defined in the present application applies solely to the case in which the connecting bodies are in a single piece with one of the covers and are welded to the other cover.

(22) With reference to FIGS. 3 and 4 different examples of are given of the connecting of two adjacent storage assemblies 20 using a connecting body 60. In these embodiments, the connecting body 60 is advantageously positioned between the storage assemblies 20 so that the height of the storage assembly connected to the connecting body is equal to the height of a storage assembly not connected to a connecting body.

(23) The connecting body 60 is electrically conductive. The constituent material of the connecting body 60 is a metal for example such as aluminium, copper etc.

(24) In the embodiment illustrated in FIG. 3, the connecting body 60 is in contact with the upper covers 50 of the storage assemblies 20 to be electrically connected. More specifically the connecting body 60 is in contact with the covers 50 at their respective skirts 53, 54. In the present invention the connecting body is in one piece with the skirt 53, 54 of one of the covers and connected by welding to the other of the covers.

(25) Therefore contrary to the prior art modules, two adjacent storage assemblies 20 are not connected using a connector strip 131 arranged ON the covers 50 but using a connecting body 60 arranged BETWEEN the covers.

(26) More specifically, the connecting body 60 is in contact: with the covers at their peripheral skirt; and/or with the tubular elements of the storage assemblies at their side wall 23.

(27) In the present invention the connecting body is in a single piece with a cover of an assembly and is secured so as to be in contact with the cover or tubular element of the other assembly.

(28) This makes it possible to minimize the height of two adjacent electrically connected storage assemblies and hence to maximize the compactness of the module thus obtained.

(29) If the body allows the connecting of two identical ends (upper or lower of the same assembly, as is the case for the two assemblies in FIG. 3, located on the same stage 30 of the module, the height of the two joined assemblies is equal to the height of each assembly (in the ideal case in which the assemblies have the same dimensions).

(30) In the embodiment illustrated in FIG. 4, the tubular element 21 of each storage assembly 20 comprises a bottom 25. Each storage assembly 20 comprises a single cover 50 intended to cap the upper open face of the tubular element 21. The connecting body 60 is firstly in contact (in the invention being in a single piece) with the upper cover 50 of a storage assembly 20 and secondly with the lower part of the tubular element 21 of an adjacent storage assembly.

(31) If the body allows the connecting of an upper end of one assembly and the lower end of another assembly as is the case in FIG. 4, for assemblies belonging to two different levels 30; 40 of the module, the height of the two joined assemblies is shorter than the sum of the heights of the assemblies.

(32) Other configurations could also be envisaged for example in which the body connects one end of one assembly with a median part of another assembly.

(33) It will be noted that the connecting body is configured in each of the cases illustrated herein so that the bulk of the two joined assemblies joined via this body is minimal, both in height and in width (namely in a direction perpendicular to the axis of the assemblies and to the direction connecting these axes). The body is effectively configured so that in this direction the dimension of the two joined assemblies is equal to the dimension of one assembly if the ideal case is considered in which all the assemblies have the same dimensions. In other words, the dimension of the connecting body does not exceed the diameter of the assembly.

(34) With reference to FIG. 5 one embodiment is illustrated of a connecting body 60. In this embodiment the connecting body 60 and a cover 50 are a single unit i.e. the cover 50 and the connecting body 60 are made in a single piece.

(35) The cover 50 comprises an annular peripheral skirt 53 and a radial tongue 70 protruding radially on the annular peripheral skirt 53 forming the connecting body. The radial tongue 70 comprises four substantially planar faces and a contact face 71 opposite the cover 50.

(36) The contact face 71 is intended to come into contact with the cover 50 or tubular element 21 of an adjacent storage assembly 20.

(37) The contact face 71 may have shape matching the shape of the cover 50 or of the tubular element 21 with which it is intended to come into contact, e.g. a concave shape.

(38) It has a profile substantially in an arc of a circle along a cross-section parallel to the upper face 61 of the connecting body 60. Therefore the shape of the contact face matches the shape of the skirt of the cover or of the tubular element on which it is intended to be secured, and the contact surface between the assembly and the connecting body is maximized. This makes it possible to increase the contact surface between the connecting body 60 and the storage assemblies 20 and hence to reduce the electrical resistance of the module.

(39) To maximize this contact surface between the connecting body 60 and the storage assemblies 20 whilst minimizing the bulk of the module: the height of each contact face 71 can be chosen to be equal to the height h of the skirt 53, 54 of a cover 50, and/or the width w of the connecting body 60 can be chosen to be equal to the diameter of the tubular element 21 or of the cover 50 with which said body is intended to come into contact.

(40) The reader will appreciate that the contact face(s) of the connecting body 60 may have profiles other than a profile in an arc of a circle.

(41) For example each contact face of the connecting body 60 may have a dove-tailed or serrated profile etc.

(42) In addition, each contact face of the connecting body may comprise a male-shaped (respectively female-shaped) cradle intended to be secured onto a support of female (respectively male) shape of the storage assembly.

(43) It is thereby mechanically possible to secure the connecting body onto the storage assembly either by interlocking or by press-fit or any other type of mechanical fastening known to persons skilled in the art. For example the cradle of the contact face may comprise a tenon (respectively a mortise) and the support of the storage assembly may comprise a mortise (respectively a tenon).

(44) With reference to FIG. 6 an illustration is given of another embodiment of the connecting body. In this embodiment each cover 50 comprises a radial tongue 64, 65 extending outwardly from the annular peripheral skirt 53 parallel to the upper face of the cover. The radial tongue of each cover forms a portion of the connecting body. Each of the tongues 64, 65 comprises a concave contact face 66, 67 opposite the cover 50. Each contact face 66, 67 is intended to come into contact with the cover of an adjacent storage assembly. The height of the radial tongue is equal to or shorter than one half of the height of the skirt.

(45) One first type of cover comprises a flush radial tongue 64 (i.e. extending in the continuation of the covering wall of the cover 50).

(46) A second type of cover comprises a radial tongue 65 extending at the free end of the annular peripheral skirt 53, parallel to the covering wall 51, 52 of the cover 50. Therefore the shapes of the two types of covers are matching shapes. To connect two adjacent storage assemblies electrically, a cover of the first type is used on one of the two storage assemblies, and a cover of the second type on the other storage assembly. These covers are positioned so that the radial tongues of the covers of the first and second type are superimposed, the lower surface 69 of the upper tongue 64 resting on the upper surface 68 of the lower tongue 65.

(47) By superimposing the radial tongues it is possible to facilitate the welding operation. Advantageously, the radial tongues 64, 65 can be welded together at the surfaces 68, 69.

(48) It will be noted that the thickness of the lower tongue 65 is preferably greater than the thickness of the upper tongue 64. In this case it may form a support allowing the welding of the tongues 64, 65 without damaging the connecting body.

(49) It is thereby possible to maximize the exchange surface between the radial tongues 64, 65 and hence to minimize the electrical resistance of the connecting body.

(50) Another variant of embodiment of the invention is also illustrated in FIG. 7. In this Figure, the cover 80 has a shape that differs from everything described previously. The cover is formed of an essentially planar disc 82 and does not comprise a peripheral skirt. The dimensions of the disc 82 are smaller than the dimensions of the end of the tubular elements 90, and it is therefore inserted into the tubular element so that the upper surface of the cover 80 lies flush with the end of the tubular element.

(51) The cover also comprises a radial tongue 84 whose height is equal to the height of the disc 82. The tongue 84 comprises a contact face 86 intended to be connected to a second assembly as described previously.

(52) It is also noted that the tubular element 90 comprises a cut-out 92 in its side wall 94 allowing the radial tongue to project from the tubular element 90 and to connect the assembly to a second adjacent assembly.

(53) It will be noted that the shape of the cover described with reference to FIG. 7 can be adopted even if the tubular element does not comprise a cut-out. In this case the cover is placed on the end of the tubular element.

(54) To summarize and with reference to FIGS. 5 to 7, the connecting body can be made in one (FIG. 5 or 7) or two parts (FIG. 6) one and/or the other of these parts possibly being in a single piece with one of the covers.

(55) However, irrespective of the configuration of the connecting body, it is never in a single piece with two covers at the same time. This allows improved flexibility for assembling of the module.

(56) A more detailed description will now be given of an example of method.

(57) If the tubular element 21 does not comprise a bottom, a cover 50 is arranged on one of the faces of the tubular element.

(58) A capacitor element 80 is positioned inside the tubular element 21. A cover 50 is placed on the open end of the tubular element then, once the connection between the tubular element 21 and the cover 50 has been sealed, the electrolyte is placed in the tubular element.

(59) A first electrical energy storage assembly is thereby obtained. These steps are repeated to obtain the number of desired storage assemblies for the module. At least one of the covers of each assembly comprises a radial tongue forming a connecting body such as described in FIG. 5;

(60) At a step of the assembling method, two energy storage assemblies are positioned side by side.

(61) The connecting body 60 is placed in contact with the skirt of the energy storage assembly 20 from which it is separate to connect this assembly electrically with the assembly with which the body is in a single piece. Advantageously, the connecting body is positioned so that the height of the storage assembly connected to the connecting body is equal to the height of a storage assembly not connected to the connecting body.

(62) The connecting body is secured onto the two storage assemblies in the invention by connecting the cover tongue, which forms a connecting body, at its contact surface with the other storage assembly. This securing can be obtained by gluing, screwing, welding or interlocking of mating parts provided on the covers and on the connecting body. Welding and in particular friction stir welding is the preferred embodiment since it allows better passing of current.

(63) These different steps can be repeated to connect a plurality of storage assemblies electrically to form modules having different properties in relation to the intended application, such as illustrated in FIG. 2 for example.

(64) The assembling of a module using the connecting body described above has numerous advantages: the different configurations of the connecting body allow good flexibility of two joined adjacent storage assemblies, at different heights and at different angles, since the connecting body is not in a single piece with the covers of both storage assemblies; the joining of two storage assemblies can be obtained using standard parts irrespective of the assembled configuration of the adjacent storage assemblies (storage assemblies positioned on different levels and/or at different angles etc.); since the parts used for joining are of simple, standard shape the manufacturing costs thereof (and hence of the module) are low; the connecting bodies allow maximized compactness of the module. Since they are integrated in the cover it is possible to simplify the assembling method which only requires a single connecting step of the assemblies; the use of a connecting body also allows improved heat evacuation; in the prior art modules in which a strip is superimposed over the cover, heat is only evacuated via the weld beads connecting the strip to the cover; on the contrary, with the use of a connecting body, heat is evacuated through the entire upper surface of the cover which is directly in contact with surrounding air; finally, the use of a connecting body according to the invention allows a reduction in the resistance of the module, the distance covered by the electric current in a module according to the invention being shorter than the distance travelled by the electric current in a module whose assemblies are connected via a connector strip superimposed over the cover.

(65) The reader will have understood that numerous modifications can be made to the method and device described in the foregoing without departing in substance from the novel teachings and advantages described herein.

(66) In particular the tubular element, the cover or the connecting body can be of different shapes to those illustrated in the Figures. For example, the connecting body may be a rod or may comprise a contact face whose shape does not match the shapes of the assembly.

(67) Therefore, any modifications of this type come within the scope of the invention such as defined in the appended claims.