BATTERY COMPRISING A MODULE AND A FIXING MEANS

Abstract

Electrical energy storage battery comprising: - a casing (1) having an internal face (Fi) for supporting a module (2), - the electrical energy storage module (2), comprising a sleeve (3) for fixing the module (2) to the internal face (Fi), - a means (5, 6) for fixing the module (2) to the internal face (Fi), comprising on the one hand a protrusion (5) of the internal support face (Fi) extending partly into the bore (A) of the sleeve (3), this protrusion (5) comprising a first thread, and on the other hand a clamping device (6) comprising a clamping head (7) extended by a threaded body (8) cooperating by screwing with the first thread, this sleeve (3) comprising a first end (E1) bearing on the internal face (Fi), and in contact with the internal face (Fi), and a second end (E2), opposite, receiving the support of the clamping head (7), the threaded body (8) penetrating the sleeve (3) through the second end (E2). Figure 1.

Description

Title of the invention: BATTERY COMPRISING A MODULE AND A FIXING MEANS

[0001] The present invention relates to a battery, and more particularly to a battery of an electrically powered vehicle powering an electric motor.

[0002] Throughout the text of this document, the term “battery” will be understood to mean an assembly comprising battery modules containing electrochemical energy storage cells. These modules comprise, for example, a strap holding the stacked cells in compression against each other, and each have an outer casing comprising interfaces for fixing this module in a casing, this casing possibly including at least part of the strapping. This battery possibly comprises electrical or electronic means for managing the electrical energy of these modules. These modules are grouped together in the casing or tray and form a battery block, called a battery, this battery block often being designated by the English expression “battery pack”, this casing generally containing a mounting interface, and connection terminals.

[0003] Furthermore, the term electrochemical energy storage cell will be understood throughout the text of this document to mean cells generating current by chemical reaction, for example of the lithium-ion (or Li-ion) type, of the Ni-Mh, or Ni-Cd or even lead type.

[0004] In this field, it is known to cool or heat the battery modules by a plate traversed by a heat transfer fluid. This plate is in contact by thermal conduction with the modules through a heat exchange surface. This plate must also be positioned and fixed in the casing.

[0005] In general, the module fixing interface comprises a screw whose free end passes through a nut welded under a sheet of the casing, the screw head bearing on the module. The free end of the screw has an elongated, non-threaded shape, for example in the form of a cone, so as to guide the screw during the screwing operation, this free end extending beyond the nut. This interface, although simple, has a drawback due to its height requirement, the height being for example along the axis of the screw: Not only does the nut extend beyond the sheet of the casing, but the free end extending beyond the nut further increases the total height of this interface.

[0006] Thus such a battery has: - either a reduced internal space and therefore a reduced energy density, - either a larger external footprint, and in particular a reduced ground clearance if this battery is fixed under a vehicle floor, which is the vast majority of situations.

[0007] The aim of the invention is to remedy this problem. To this end, the invention relates to an electrical energy storage battery comprising: - a casing having an internal face for supporting a module, - the electrical energy storage module, comprising a sleeve for fixing the module to the internal face, - a means for fixing the module to the internal face, comprising on the one hand a protrusion of the internal support face extending partly into the bore of the sleeve, this protrusion comprising a first thread, and on the other hand a clamping device comprising a clamping head extended by a threaded body cooperating by screwing with the first thread, this sleeve comprising a first end bearing on the internal face, and in contact with the internal face, and a second, opposite end, receiving the support of the clamping head, the threaded body penetrating the sleeve through the second end.

[0008] Thus the protrusion makes it possible to center the module relative to the casing by penetrating the fixing sleeve. In addition, the clamping head of the clamping device makes it possible to press the fixing sleeve against the casing. But above all, this protrusion extends into the sleeve and cooperates by threading with the clamping device, so that the first thread and the threaded body cooperate in an area located in an internal space delimited by the casing. In other words, the internal face being for example the bottom of the casing, this fixing means not only may not protrude outside this bottom, and therefore has a reduced external size, but also does not reduce the useful internal space of the casing (i.e. the space available for housing the modules) since it is integrated into the sleeve itself of the module.

[0009] According to one embodiment of the invention, the protrusion is a second sleeve whose bore comprises the first thread. This second sleeve is for example a smooth nut with a flange, this flange bearing and / or welded on a face of the casing opposite the internal support face. The smooth part of the nut is configured so as to center the module relative to the casing.

[0010] According to one embodiment of the invention, the clamping device is a screw. Thus the clamping head is the screw head, and the threaded body of this screw is screwed into the thread of the smooth nut with collar according to the previous example.

[0011] According to one embodiment of the invention, this screw has a free end opposite the tightening head, the length of the threaded body being configured so that the free end occupies a position between a position protruding from the second sleeve by a value at most equal to 1.5 times the diameter of the screw, and a non-emerging position of the second sleeve.

[0012] According to one embodiment of the invention, this free end forms a cone engagement of the screw in the second sleeve.

[0013] According to one embodiment of the invention, the protrusion is an added element fixed to the casing. For example, the added element is welded to the casing.

[0014] According to one embodiment of the invention, the internal face is a double bottom of the casing, or alternatively a boss of the casing on which the first end rests and is in contact.

[0015] This double bottom is not necessarily over the entire surface of the bottom of the casing. This double bottom is for example located around the protrusion, in particular this double bottom is a stiffening crosspiece of the internal support face, in particular a casing bottom crosspiece.

[0016] According to one embodiment of the invention, this double bottom of the casing or this boss of the casing having respectively: a void of a height, and a variation in height of the internal face, of 16 mm maximum each.

[0017] According to one embodiment of the invention, the module comprises: - a first and second end of the module, - two sides connecting the two ends together, the fixing sleeve being secured to an outer face of one of the sides.

[0018] This arrangement makes it possible to have a fixing sleeve on one side of the module, and in particular on each side of the module, i.e. on two opposite sides. The positioning of the fixing sleeves can therefore be chosen at any location depending on the length of the module, i.e. between its two ends.

[0019] This sleeve has for example an axis orthogonal to the internal face. This sleeve is for example coaxial with the protrusion. This sleeve is for example integral with the module by assembly, hooping, or made from the material on the side of the module.

[0020] Other features and advantages will appear on reading the following description of a particular, non-limiting embodiment of the invention, made with reference to the single [Fig.l] in which:

[0021] [Fig.l]: represents a schematic sectional view of an electrical energy storage battery according to an embodiment of the invention.

[0022] [Fig.l] discloses an electrical energy storage battery comprising, according to the invention: - a casing 1 having an internal face Fi for supporting a module 2, - the electrical energy storage module 2, comprising a fixing sleeve 3 of the module 2 to the internal face Fi, - a means 5, 6 for fixing the module 2 to the internal face Fi, comprising on the one hand a protrusion 5 of the internal support face Fi extending partly into the bore A of the sleeve 3, this protrusion 5 comprising a first thread, and on the other hand a clamping device 6 comprising a clamping head 7 extended by a threaded body 8 cooperating by screwing with the first thread, this sleeve 3 comprising a first end El bearing on the internal face Fi, and in contact with the internal face Fi, and a second end E2, opposite, receiving the support of the clamping head 7, the threaded body 8 penetrating the sleeve 3 through the second end E2.

[0023] For example, the electrical energy storage module 2 comprises a heat exchange surface S.

[0024] For example and in a manner not illustrated, this battery comprises a plate for heat exchange by conduction with the heat exchange surface S, inserted between this heat exchange surface S and the internal support face Fi, this plate comprising in its thickness a hollow part intended to receive a heat transfer fluid, and a solid part crossed by a hole over its entire thickness.

[0025] In a manner not illustrated, this casing is closed by a cover so as to form a hermetic internal space containing the modules. This cover is for example formed by a part of the floor of a motor vehicle but not necessarily. For example this battery, that is to say a battery according to the preceding definition, can be assembled outside the vehicle (casing, module, cover) then fixed, once assembled, to the motor vehicle and in particular under the floor of this motor vehicle. This vehicle is for example electrically powered, the battery powering an electric motor. For example this vehicle is a so-called hybrid vehicle, or with fully electric propulsion. An application is also possible outside the automotive field, for example for construction site stations such as generator sets, or electrical energy storage plants.

[0026] This battery possibly includes electrical or electronic means for managing the electrical energy of these modules, for example and in a non-exhaustive manner: a charger, a current converter, a battery pack control computer, an inverter, charge and discharge control cards for each module and / or each cell, a junction box including contactors for electrical isolation of the battery pack or for cutting off and energizing external circuits connected to the battery pack. All these electrical or electronic means can be integrated at the level of each cell, and / or each module.

[0027] The internal support face Fi of the module 2 is in this example the bottom of the casing 1, this casing 1 forming a container closed by a cover not shown. [Fig.l] illustrates a partial view of this bottom in section.

[0028] It will be noted that in [Fig.l], for simplicity, only the sections of module 2, fixing sleeve 3, and protrusion 5 are hatched, according to the practice of industrial drawings. In particular, the hatching of module 2 is purely for the purpose of legibility of the figure, it is clearly implicit that this module 2 is not a block of solid material but as previously described contains, among other things, cells.

[0029] The heat exchange surface S is here a bottom of the module 2, opposite the bottom of the casing 1 and therefore the internal face Fi, but this arrangement is not obligatory: the internal face Fi may for example not be the bottom of the casing 1, but another part of the casing 1 such as the cover or any face of the casing 1 opposite the heat exchange surface S, thus the heat exchange surface S is not necessarily the bottom of the module 2 but may be a top or side Cl of the module 2, which is why the bottom, like the top of the module 2 is also called “side” (S) in this example.

[0030] The heat exchange plate, not illustrated, is a plate well known to those skilled in the art, and which is produced by assembling two sheets one on top of the other, a first of the two sheets having a stamped depression covered by the second sheet and thus forming a hollow part. This assembly is produced for example by electric welding and / or by gluing for good sealing. These sheets can be metallic or made of plastic. This hollow part forms for example a channel running through the heat exchange plate along a surface corresponding to the heat exchange surface S. The heat transfer fluid is circulated in this channel by a circulation pump, integrated or not in the hermetic internal space of the battery. The solid part is formed by the junction between the first and the second sheet.

[0031] Other cooling plate technologies are known and applicable to this invention, for example plates resulting from a foundry or machining process with more or less complex assemblies, or by large plastic deformation of a single sheet by blowing. The channel can be a narrow channel winding through the plate, or a blade-shaped channel crossing the cooling plate in only one direction, this is not important for the invention presented.

[0032] The clamping device 6, thanks to its clamping head 7, will clamp the sleeve 3 against the internal face Fi. The clamping head 7 illustrated is only one example among others, and is in [Fig.l] a screw head with a wide head, that is to say wider than the bore of the sleeve 3 and therefore covering the second end E2. The sleeve 3 takes up the entire clamping force of the clamping device 6.

[0033] The protrusion 5 is a second sleeve 5 whose bore comprises the first thread. This second sleeve 5 is for example a socket, just like the sleeve 3.

[0034] The clamping device 6 is illustrated as a large-headed screw, but alternatively could be a smooth, shouldered nut.

[0035] In [Fig.l] a significant clearance is shown between the sleeve 3 and the second sleeve 5. This clearance will, for example, be slippery if precise positioning is required. relative between the module 2, and the internal face Fi. This clearance will be wider if there are several sleeves 3 for the same module 2 so as to absorb manufacturing dispersions. This clearance may be further increased, for example 3 to 6 mm at the radius, for reasons of hyperstaticity. Similarly, the person skilled in the art will know how to adapt the shape of the sleeve 3 and the second sleeve 5 according to the degrees of freedom to be immobilized.

[0036] This screw 6 has a free end EL opposite the clamping head 7, the length of the threaded body 8 being configured so that the free end EL occupies a position between a position projecting from the second sleeve 5 by a value at most equal to 1.5 times the diameter of the screw, and a non-emerging position of the second sleeve 5.

[0037] For example, this position is flush with the second sleeve 5.

[0038] For example, this position exceeds by a maximum of 16 mm, for example between 16mm and 0mm.

[0039] This free end EL forms for example a cone for engaging the screw 6 in the second sleeve 5 but this is not obligatory, this shape can be for example cylindrical, or simply not present. This free end EL will for example be locally devoid of thread.

[0040] It will of course be noted that the position is measured relative to the most extreme part of the free end EL, for example the top of the cone shape.

[0041] the protrusion 5, and therefore the second sleeve 5, is an element added and fixed to the casing 1, like a shouldered socket or a stamped bridge, but in a variant, not illustrated, this protrusion 5 can be a deep boss of the internal face Fi comprising a threaded nut at its bottom to receive the clamping device 6.

[0042] For example, the added element 5 is welded to the casing 1 on its shoulder, or screwed, or glued.

[0043] As a variant, the added element 5 is a stud, in particular a stud welded to the internal face Fi.

[0044] The internal face Fi is a double bottom 9 of the casing 1, as illustrated in [Fig. 1], and alternatively a boss of the casing 1. In [Fig.l], the double bottom is in fact a sheet metal crosspiece in the shape of an inverted U, the ends of the U of which are welded to the bottom of the casing 1. This U then forms with the bottom of the casing 1 a hollow body that is out of line with the bottom of the casing, this U being located under the sleeve 3. The second sleeve 5 will for example be assembled on this crosspiece before welding this crosspiece to the bottom of the casing.

[0045] This double bottom 9 of the casing 1 or this boss of the casing 1 presents respectively: a void of a height, and a variation in height of the internal face Fi, of 16 mm maximum each, but this can be much less. In fact this arrangement allows precisely that, whatever the height of the void, or the variation in height of the face internal Fi, the free end EL does not protrude from the bottom of the casing.

[0046] This module 2 includes: - a first and second module end, - two sides S, Cl connecting the two ends together, the fixing sleeve 3 being integral with an outer face of one of the sides Cl.

[0047] For example, this module 2 further comprises: - a stack of electrochemical cells compressed between the two module ends, the two sides S, Cl being joined, the heat exchange surface S being an outer face of one side S, the fixing sleeve 3 being integral with an outer face of the other side Cl.

[0048] This first and second end are part, for example, of a strapping maintaining the stacked cells in compression against each other, and the sides S, Cl can be part of the strapping but also be independent of it, that is to say not participating in maintaining the compression of the cells. In all cases, these sides, for example four in number to form with the two ends a rectangular parallelepiped, form an outer envelope of the module 2 comprising fixing interfaces (subject of the invention) of this module 2 in the casing 1, this envelope can therefore include part of the strapping. Thus the side Cl carrying the fixing sleeve 3 is for example made of metallic material, in particular aluminum, a tab made of this material or added extending orthogonally to the side Cl and this tab comprising the fixing sleeve 3. For example, this tab and the fixing sleeve 3 form only one piece.For example, this side Cl, the tab, and the fixing sleeve 3 form a single piece. For example, this jaw 3 is shrunk or force-fitted into the tab. Of course, this tab is not essential; the fixing sleeve 3 can, for example, be attached to the side Cl.

[0049] This same side 1 may further comprise several fixing sleeves 3, aligned and extending along the length of the side 1. The battery pack containing several modules, a first module 2 adjacent to a second module 2 may for example have the fixing sleeves 3 staggered relative to each other.

[0050] The axis of the fixing sleeve 3 is for example parallel to the side Cl and orthogonal to the internal face Fi, the protrusion 5 being concentric to the fixing sleeve 3.

[0051] Electrochemical cells are, for example, parallelepiped or prismatic, and their chemistry is enclosed in a rigid envelope.

[0052] Alternatively, the cells are in the form of pockets.

[0053] These cells are alternatively cylindrical, but in this case the person skilled in the art knows that they do not need to be compressed between them because the cylinder, rigid, and by its shape, prevents the cells from swelling. The strapping then no longer has the function of compressing the cells but of positioning them. However, we will find a envelope containing all of these cells, forming a module, this envelope also being parallelepiped and having two ends and four sides, these sides being equivalent to the sides S, Cl of the present description and the fixing sleeve 3 being integral with an external face of the other side Cl.

[0054] For example, these cells are of the lithium-ion (or Li-ion) type.

Claims

Claims

1. Electrical energy storage battery comprising: - a casing (1) having an internal face (Fi) for supporting a module (2), - the electrical energy storage module (2), comprising a sleeve (3) for fixing the module (2) to the internal face (Fi), - a means (5, 6) for fixing the module (2) to the internal face (Fi), comprising on the one hand a protrusion (5) of the internal support face (Fi) extending partly into the bore (A) of the sleeve (3), this protrusion (5) comprising a first thread, and on the other hand a clamping device (6) comprising a clamping head (7) extended by a threaded body (8) cooperating by screwing with the first thread, this sleeve (3) comprising a first end (El) bearing on the internal face (Fi), and in contact with the internal face (Fi), and a second end (E2), opposite, receiving the support of the clamping head (7), the threaded body (8) penetrating the sleeve (3) through the second end (E2).

2. Battery according to claim 1, the protrusion (5) being a second sleeve (5) whose bore comprises the first thread.

3. Battery according to one of the preceding claims, the clamping device (6) being a screw (6).

4. Battery according to claim 3 in combination with claim 2, this screw (6) having a free end (EL) opposite the tightening head (7), the length of the threaded body (8) being configured so that the free end (EL) occupies a position between a position protruding from the second sleeve (5) by a value at most equal to 1.5 times the diameter of the screw, and a non-emerging position of the second sleeve (5).

5. Battery according to claim 4 or 3, this free end (EL) forming a cone for engaging the screw (6) in the second sleeve (5).

6. Battery according to one of the preceding claims, the protrusion (5) being an added element and fixed to the casing (1).

7. Battery according to claim 6, the insert (5) being welded to the casing (1).

8. Battery according to one of the preceding claims, the internal face (Fi) comprising a double bottom (9) of the casing (1) or a boss of the casing (1) on which the first end (El) is supported and in contact.

9. Battery according to claim 8, this double bottom (9) of the casing (1) or this boss of the casing (1) having respectively: a void of a height, and a variation in height of the internal face (Fi), of 16 mm maximum each.

10. Battery according to one of the preceding claims, the module (2) comprising: - a first and second module end, - two sides (S, Cl) connecting the two ends together, the fixing sleeve (3) being integral with an outer face of one of the sides (Cl).

Images