End arrangement for mobility device battery - mobility device battery comprising such an end arrangement

Abstract

The invention relates to an end arrangement (100) for a mobility device battery comprising at least one outer element (10) and one inner element (20), arranged to form in the assembled state a honeycomb structure (150), the inner element comprising a wall (1, 21) arranged to be in contact with a cell (300) of the battery (500). The invention also relates to a battery comprising at least one such end arrangement. FIGURE 4a

Description

Title of the invention: End arrangement for a mobility device battery - mobility device battery comprising such an end arrangement

[0001] The present application relates to the field of mobility device batteries, in particular batteries used in an electric vehicle, a hybrid electric vehicle or a plug-in hybrid electric vehicle.

[0002] Following the popularization of electric or hybrid mobility, notably combining electric and thermal propulsion, it is necessary to control the capacity, efficiency and lifespan of the batteries used.

[0003] In a known manner, a battery used for an electric or hybrid mobility device comprises a plurality of cells.

[0004] The curve below shows the temperature of the 72 cells of a battery in cold weather. We can see that the end cells are about 10°C cooler than the central cells. However, it is known that the performance of a battery is linked to the temperature homogeneity of the cells. It is the cell with the most divergent temperature that will have the greatest impact on the performance of the battery.

[0005] There is a need to reduce the temperature difference between the different cells of a battery.

[0006] Utility model CN216529114U discloses a battery module comprising a battery end plate having a contact area with the battery cells which is flexible to resist the expansion force generated by the charging and discharging cycles of the battery. After a few cycles the thermal performance of the end plate will degrade due to axial contact.

[0007] There is a need to improve existing end plates, particularly to improve the thermal insulation they provide.

[0008] To meet all or part of these needs, the invention according to a first aspect relates to an end arrangement for a mobility device battery comprising at least one external element and one internal element, arranged to form in the assembled state a honeycomb structure, the internal element comprising a wall arranged to be in contact with a battery cell.

[0009] The outer and inner elements are distinct, that is to say, within the meaning of the present invention, they are manufactured separately, in particular by molding, extrusion, or any other appropriate method known to those skilled in the art.

[0010] Each exterior and interior element is manufactured in one or more pieces, advantageously manufactured in a single piece.

[0011] According to different variants of the invention, the outer and inner elements are assembled by gluing, force fitting, hot riveting, clipping, fitting, pinching by an enveloping structure, or any other suitable method known to those skilled in the art.

[0012] Advantageously, the wall of the inner element is weakly conductive.

[0013] In the following description, - the terms horizontal, vertical and lateral relate to the orientation of a battery placed on a flat surface. - the axial term corresponds to a direction along the axis of the battery.

[0014] Advantageously, the outer element comprises a wall and, in the assembled state, the honeycomb structure is located between the wall of the outer element and the wall of the inner element.

[0015] According to variants of the invention, the honeycomb structure may be part of the external element, in particular of a single-piece external element, the honeycomb structure being in particular integral with the wall of the external element.

[0016] Alternatively, the honeycomb structure may be part of the interior element, in particular of a single-piece interior element, the honeycomb structure being in particular integral with the wall of the interior element.

[0017] According to yet another variant, the outer element cooperates with the inner element to form the honeycomb structure in the assembled state.

[0018] The end arrangement may comprise a frame.

[0019] The outer element may comprise a frame, for example forming the frame of the end arrangement.

[0020] The inner element may comprise a frame, for example forming the frame of the end arrangement.

[0021] The outer member and the inner member may each comprise a frame forming in the assembled state the frame of the end arrangement.

[0022] Depending on the embodiments, the end arrangement according to the invention may alternatively or additionally have one of the following characteristics: - the outer element and / or the inner element comprises a series of vertical stiffeners, i.e. at least one vertical stiffener, preferably several. Said vertical stiffeners are spaced regularly or not over a horizontal dimension of said element. the outer element and / or the inner element comprises a series of horizontal stiffeners, i.e. at least one horizontal stiffener, preferably several. Said horizontal stiffeners are spaced regularly or not over a vertical dimension of said element. the outer element and the inner element each comprise stiffeners, the stiffeners of the outer element and the stiffeners of the inner element being arranged to cooperate with each other. The stiffeners of the outer and inner elements thus form the honeycomb structure. at least one of the stiffeners has a thickness less than a gap between the wall of the inner element and the wall of the outer element. For the purposes of the invention, the thickness of a stiffener means its maximum dimension measured perpendicularly from the wall of the corresponding element. For the purposes of the invention, the thickness of an element means its maximum dimension measured perpendicularly from its wall. at least one height of one of the vertical stiffeners is less than a height of the end arrangement. For the purposes of the invention, the height of a stiffener means its maximum vertical dimension measured parallel to the wall of the corresponding element. In the context of the invention, when the end arrangement comprises a frame, the height of the end arrangement is measured inside this frame. at least one width of one of the horizontal stiffeners is less than a width of the end arrangement. For the purposes of the invention, the width of a stiffener means its maximum horizontal dimension measured parallel to the wall of the corresponding element. In the context of the invention, when the end arrangement comprises a frame, the width of the end arrangement is measured inside this frame. the end arrangement comprises, once assembled, at least one passage for circulating a cooling fluid, in particular a gas or a liquid. Said passage is in particular arranged to circulate from at least one inlet a cooling fluid coming from or going to cells of the battery. The passage can be located between two parallel, vertical or horizontal stiffeners. The circulation of the fluid can be vertical or horizontal. The cooling fluid is for example a gas such as air or water in particular with a dielectric additive. the external element, in particular its wall, and / or the internal element, in particular its wall, comprises at least one orifice connected to the circulation passage of fluid. - the wall of the outer element and the wall of the inner element cover at least half, or even three-quarters of the surface of the end element. - the end arrangement, in particular the inner element, comprises at least one cooling fluid inlet. - the end arrangement, in particular the outer element, comprises at least one cooling fluid outlet, in particular an air or liquid outlet. - the outer element and the inner element are identical, in particular arranged to be assembled in a mirror image or head to tail. For the purposes of the invention, identical means that they are manufactured using the same manufacturing process, in particular from the same mold. The outer element and the inner element thus have the same dimensions. They may be made of the same material or different materials; for example, the inner element may be made of a more insulating material than the outer element.

[0023] Alternatively or additionally, the outer element may be made of a more rigid material than the inner element; for example, the outer element is injected with a fiber-reinforced material while the inner element is not. In this example, they may be of a different color to differentiate them. Identical outer and inner elements are, for example, assembled in a mirror image or head to tail.

[0024] Within the meaning of the invention, identical exterior and interior elements may have a structural difference corresponding to an additional manufacturing step. For example, an orifice may be added to create an inlet or outlet for the cooling fluid.

[0025] According to another aspect, the invention relates to a mobility device battery comprising a plurality of cells, a first end arrangement and a second end arrangement, at least one of the first and second end arrangements being an end arrangement as described above. Preferably, both end arrangements, the first and the second, are end arrangements according to the first aspect of the invention.

[0026] The battery is not limited to a particular voltage. It can be "high voltage" or "low voltage".

[0027] The battery can be air-cooled or water-cooled, in particular with a dielectric fluid.

[0028] Depending on the embodiments, the battery according to the invention may alternatively or additionally have one of the following characteristics: - the first and second end arrangements are attached to the plurality of cells by at least one retaining bar. Said retaining bar has preferably at least one oblong hole. This shape allows axial loads to be taken from the end arrangements. It facilitates axial play or axial compression of the cells. It allows clamping for a range of relative positions. - The support bar(s) are preferably metal. - the mobility device battery comprises a channel for circulating cooling fluid in the end arrangement, in particular air or liquid, from or to the cells. The channel is in particular arranged to cooperate with at least one orifice of an end element. Said orifice can be arranged to serve as an inlet and / or outlet. Advantageously, the flow of cooling fluid in the end arrangement is in the opposite direction to the flow which passes between the cells. Thus, the thermal insulation is notably improved. The flow in the end arrangement makes it possible to thermally insulate the end cell in contact with the wall of the inner element.

[0029] According to yet another aspect, the invention relates to a mobility device battery comprising a plurality of cells, a first end arrangement and a second end arrangement, a cooling fluid circulation system cooperating with at least one of the first and second end arrangements, the flow of cooling fluid in the at least one of the end arrangements being in the opposite direction to the flow which passes between the cells.

[0030] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below for information purposes in relation to drawings in which:

[0031] - [Fig.l] illustrates an example of a battery according to the invention,

[0032] - [Fig.2] is an exploded view of detail II of [Fig.l],

[0033] - [Fig.3a] is a partial sectional view of an end arrangement according to the invention in a first embodiment,

[0034] - [Fig.3b] is a front view, interior side of the exterior element of the end arrangement of [Fig.3a],

[0035] - Figures 4a to 4c show in partial section details of the battery according to variants of the invention,

[0036] - Figures 5a to 5c show different views of end arrangements according to the invention,

[0037] - Figures 6a to 6c show different views of exterior and interior elements of a example of an end arrangement according to the invention,

[0038] - figures 7a to 7c are equivalent to figures 6a to 6c for the external elements and interior of another example of an end arrangement according to the invention,

[0039] - Figures 8a to 8c illustrate the exterior and interior elements of yet another example of an end arrangement according to the invention, and

[0040] - Figure 9a corresponds to [Fig.6a] for a variant of end arrangement according to the invention.

[0041] In these figures, similar elements bear the same references.

[0042] The following embodiments are examples. Although the description refers to a or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Single features of different embodiments may also be combined or interchanged to provide other embodiments.

[0043] In the description, certain objects may be indexed, such as, for example, first object or second object. In this case, it is a simple indexing to differentiate and name close but not identical objects. This indexing does not imply a priority of one object over another and such names can easily be reversed without departing from the scope of the present description. This indexing also does not imply an order in time.

[0044] The mobility device battery 500 illustrated in [Fig. 1] comprises a plurality of cells 300, in the example 72 in number, a first and a second end arrangement 100 and 200. Each end arrangement 100, 200 comprises a separate outer element 10 and an inner element 20. Each inner element 20 comprises a wall 1, 21, preferably weakly conductive, which is in contact with an end cell 300 of the battery 500. The first end arrangement 100 is thus in contact with a first end cell 301 of the battery 500, and the second end arrangement 200 is in contact with a second end cell 302 of the battery 500,

[0045] The end arrangements 100, 200 are here fixed to the plurality of cells 300 by four holding bars 900 located at the four peaks of the plurality of cells 300. Advantageously, the holding bars help both to maintain the end arrangements and to maintain the cells together, next to each other. The holding bars facilitate taking into account the expansion of the cells.

[0046] [Fig. 2] illustrates in perspective and in exploded view various components of the battery of [Fig. 1]. It shows the attachment of one of the retaining bars 900 on each first and second end arrangements 100 and 200 of the illustrated example. The retaining bar 900 is here in the form of a bracket formed of a lateral part at right angles to a horizontal part. The retaining bar 900 has a fixing hole 950, advantageously here an oblong hole. A screw 960, or a rivet, in particular a self-locking rivet, ensures the fixing through the oblong hole 950 and a cor corresponding 955 of the end arrangement. Said hole 950 is here located on the horizontal part of the holding bar 900. In a variant not illustrated it is located on the lateral part. According to yet another variant not illustrated the holding bar has a hole on a horizontal part and a hole on a lateral part.

[0047] [Fig.3a] illustrates in partial section an end arrangement 100, 200 according to a first embodiment. The end arrangement 100, 200 comprises a frame 2, two walls 12 and 11 and a honeycomb structure 150 formed by stiffeners 50.

[0048] While the inner element 20 is formed from the wall 21, the outer element 10 comprises the wall 11 and a frame 12 forming the frame 2 of the end arrangement as well as stiffeners 51.

[0049] The wall 11 further comprises fixing holes 990, for example to allow sheaths or other parts of the battery to be fixed to the wall 11.

[0050] As shown in [Fig.3b], the external element 10 also comprises stiffeners 51, more particularly here a series of vertical stiffeners 50v spaced regularly over a horizontal dimension 15 of the element 10 and a series of horizontal stiffeners 50h spaced regularly over a vertical dimension 16 of the element 10.

[0051] The batteries 500 partially illustrated in Figures 4a to 4c comprise a channel 700. The fluid thus evacuated, here air, comes from the cells 300 of the battery 500, it enters the end arrangement 100 through the inlet 40, passes through the passage 70, leaves through the outlet 80 and ends up in the channel 700. Advantageously here the cold fluid Ac, shown in dotted lines, passes through the cells 300. It is notably guided by grids 370 positioned between two adjacent cells 300. Its temperature increases on contact with the cells, the cooling fluid Ah thus heated is shown in solid lines. Such circulation of fluid in the cells then through the end arrangement improves the performance of the battery 500. Cooling of the battery is facilitated while allowing better homogeneity of the cell temperatures.

[0052] Whereas in the example of [Fig.4a] the cooling fluid discharged via the channel 700 from the cells 300 passes entirely through the end arrangement 100, in the variant of [Fig.4b], a portion of the fluid heated by the cells is discharged directly into the channel 700 and only a portion passes through the end arrangement 100.

[0053] In the variant of [Fig.4c], a part of the cooling fluid heated by the cells is discharged directly into the channel 700 and only a part passes through the end arrangement 100.

[0054] Similarly, the second end arrangement 200, not shown in FIGS. 4a to 4c, may comprise a channel 700.

[0055] In another variant, a portion of the cooling fluid heated by the cells passes through the end arrangement 200 before being discharged directly into the channel 700 located on the side of the first end arrangement 100.

[0056] In the following figures are illustrated different embodiments of the honeycomb structure 150 and the passage 70.

[0057] The end arrangement 100,200 illustrated in Figures 5a to 5c comprises, once assembled, a passage 70 for circulating cooling fluid from or to the cells of the battery between orifices 48. These orifices are arranged to serve as an inlet or outlet, depending on the battery. In the example described, the end arrangement 100,200 comprises two passages 70 as shown in [Fig.5b]. These passages are located between two vertical stiffeners 50v. The horizontal stiffeners 50h of the outer element 10 have a variable thickness e. At the passages 70 this thickness e is less than a gap e0 between the wall 21 of the inner element 20 and the wall 11 of the outer element 10 as shown in [Fig.5a] which illustrates the end arrangement 100,200 assembled in section along AA. Furthermore, Figures 5a and 5b show that the height ho of the outer element 10 is greater than the height h5 of the vertical stiffeners 50v.The outer element 10 comprises an orifice 48. The inner element 20 does not entirely cover the surface of the end arrangement 100,200, i.e. here the surface of the inner element 20 in order to create a second orifice 48 of the end arrangement 100,200. The wall of the inner element 20 here covers 4 / 5 of the surface of the end arrangement 100,200. More generally, advantageously the walls of the outer and inner elements cover at least half, or even ¾ of the surface of the end arrangement.

[0058] In the end arrangement examples 100, 200 described below, the outer element 10 and the inner element 20 each comprise stiffeners 50. The stiffeners 51 of the outer element 10 and the stiffeners 52 of the inner element 20 are arranged to cooperate with each other. They thus form the honeycomb structure 150.

[0059] In the examples illustrated in Figures 6a to 6c and 7a to 7c, the outer and inner elements 10 and 20 are identical. Here they are arranged to be assembled in a mirror image.

[0060] The outer and inner elements 10 and 20 of the end arrangement 100, 200 illustrated in FIGS. 6a to 6c comprise a series of vertical stiffeners 50v and a series of horizontal stiffeners 50h. The horizontal stiffeners are here spaced regularly over a vertical dimension 16, respectively 26, of the corresponding element.

[0061] [Fig.6c] illustrates the assembled end arrangement 100,200 in section along CC. Once assembled, the end arrangement 100,200 comprises, as illustrated in [Fig.6c] a passage 70 located between the outer and inner elements 10 and 20 to make circulate cooling fluid between two orifices 48. The orifices 48 are in particular arranged to be able to serve as an inlet or outlet for the cooling fluid. Depending on the battery, the cooling fluid can circulate in the end arrangement 100,200 from the battery cells. In a battery variant, the cooling fluid circulates from the outside in the end arrangement 100,200 and exits towards the battery cells. The passage 70 is located between two vertical stiffeners 50v. The horizontal stiffeners 50h of the outer and inner elements 10 and 20 have a variable thickness e. This thickness e is here equal to half of the gap e0 between the wall 21 of the inner element 20 and the wall 11 of the outer element 10 except at the level of the passage 70. To form the passage 70, the thickness e is then strictly less than half of the gap e0.

[0062] The outer and inner elements 10 and 20 of the end arrangement 100 illustrated in FIGS. 7a to 7c also comprise a series of vertical stiffeners 50v and a series of horizontal stiffeners 50h. The horizontal stiffeners are here irregularly spaced over a vertical dimension 16, respectively 26, of the corresponding element. In this example the outer and inner elements 10 and 20 are manufactured from a single mold and the orifices 48 are then cut out before assembly.

[0063] The outer and inner elements 10 and 20 of the end arrangement 100 illustrated in FIGS. 8a to 8c are also identical. They are here arranged to be assembled head to tail. [Fig. 8a] shows from the front one of the outer and inner elements 10 and 20. They are placed head to tail before assembly, as illustrated from the side in [Fig. 8b]. They are finally assembled as shown in [Fig. 8c]. The orifice 48 of each element is made at the time of manufacture of the outer and inner elements 10 and 20, directly at the time of molding or in a later step.

[0064] In the example illustrated in [Fig.9a], the outer and inner elements 10 and 20 are identically arranged to be assembled in a mirror image. Once assembled, the end arrangement 100, 200 comprises a frame formed by the frame 21 of the outer element 10 and the frame 22 of the inner element 20. It also comprises a passage 70 located between the outer and inner elements 10 and 20 for circulating cooling fluid between two orifices 48. While the passage 70 is vertical in the example of FIGS. 6a to 6C, it is horizontal here. The passage 70 is located between two horizontal stiffeners 51, 50h of the outer element 10 and two horizontal stiffeners 52, 50h of the inner element 20. The vertical stiffeners 50v of the outer and inner elements 10 and 20 have a variable thickness e. At the level of the passage 70 this thickness e is less than half of the gap e0 between the wall 21 of the inner element 20 and the wall 11 of the outer element 10.In this example the horizontal stiffeners 50h have a width l5 equal to a width l0 of the end arrangement. In a variant not illustrated at least a width l5 of one of the ra- . horizontal disseurs is less than the width l0 of the end arrangement. This example of end arrangement is particularly used for a battery with fluid circulation on the side faces of the battery.

[0065] In the illustrated battery examples, the cooling fluid comes from the cells, passes through at least one passage of an end arrangement and exits into the channel. In a variant of the invention not shown, the cooling fluid comes from the channel of the battery, passes through at least one passage of an end arrangement and exits towards the cells, being guided in particular by grids between the cells. Thus the outer element may comprise at least one orifice to form a cooling fluid inlet. Similarly, the inner element may comprise at least one orifice to form a cooling fluid outlet.

Claims

Claims

1. Battery (500) for a mobility device comprising: a plurality of cells (300); a first end arrangement (100) and a second end arrangement (200), at least one of the first and second end arrangements, preferably both, comprising at least one outer element (10) and one inner element (20), arranged to form in the assembled state a honeycomb structure (150), the inner element comprising a wall (1, 21) arranged to be in contact with a cell of the battery; a channel (700) for circulating cooling fluid from or to the cells (300), the channel (700) cooperating with at least one passage (70) of one of the first or second end arrangements (100, 200), the flow of cooling fluid in the arrangement of one of the first or second end arrangements (100, 200) being in the opposite direction to the flow which passes between the cells (300).

2. Mobility device battery according to claim 1, the outer element (10) and / or the inner element (20) comprising a series of vertical stiffeners (50v), said vertical stiffeners being spaced regularly or not over a horizontal dimension (15, 25) of said element.

3. A mobility device battery according to any one of the preceding claims, the outer element (10) and / or the inner element (20) comprising a series of horizontal stiffeners (50h), said horizontal stiffeners being spaced regularly or not over a vertical dimension (16, 26) of said element.

4. A mobility device battery according to any one of the preceding claims, the outer element (10) and the inner element (20) each comprising stiffeners (50, 50v, 50h, 51, 52) and the stiffeners of the outer element (51) and the stiffeners of the inner element (52) being arranged to cooperate with each other.

5. Mobility device battery according to any one of claims 2 to 4, at least one of the stiffeners (50, 50v, 50h, 51, 52) having a thickness (e) less than a gap (e0) between the wall (21) of the inner element (20) and a wall (11) of the outer element (10).

6. Mobility device battery according to any one of claims 2 to 5, at least one height ( / z5) of one of the vertical stiffeners (50v) being less than a height (h0) of the end arrangement.

7. A mobility device battery according to any one of claims 2 to 6, at least one width (Z5) of one of the horizontal stiffeners (50h) being less than a width (l0) of the end arrangement.

8. A mobility device battery according to any preceding claim, said passage (70) being arranged to circulate cooling fluid from cells of the battery from at least one inlet (40).

9. Mobility vehicle battery according to the preceding claim, said passage (70) comprising at least one outlet (80) for evacuating the cooling fluid.

10. Mobility device battery according to any one of the preceding claims, the outer element (10) and the inner element (20) being identical and in particular arranged to be assembled in a mirror or head to tail manner.

11. A mobility device battery according to any preceding claim, the first and second end arrangements being secured to the plurality of cells (300) by at least one retaining bar (900) preferably having at least one oblong hole (950).

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