Support structure for a motor vehicle battery assembly

Abstract

NOT VISIBLE DUE TO STATUS OF PATENT

Description

[0001] Support structure of a motor vehicle battery assembly

[0002] The present invention relates to the field of motor vehicle battery assemblies, and in particular to a support structure for a motor vehicle battery assembly.

[0003] An electric or hybrid drive motor vehicle has a battery pack assembly (or "battery pack"), comprising a battery and a support structure defining a battery receiving housing and configured to secure the battery pack to the motor vehicle.

[0004] The battery comprises a plurality of battery elements (or "battery cells" or "battery accumulators") supported by the support structure. Each battery element is a device, for example electrochemical, capable of storing electrical energy and then releasing the electrical energy. Several battery elements can be grouped together to form a battery module, i.e. a group of several battery elements attached together so that they can be handled as a single unit.

[0005] The electrical energy stored and released by the battery is used to supply electricity to the electrical components of the motor vehicle, in particular one or more electric motors driving the electric vehicle.

[0006] A battery has a high weight. In order to lower the center of gravity of a motor vehicle equipped with the battery, the battery support structure is, for example, configured to secure the battery under a floor of the motor vehicle.

[0007] The space available under the floor of a motor vehicle is limited. This space is also exposed when the vehicle is moving, particularly to impacts from objects passing under the vehicle. It is desirable that the support structure protects the battery from such attacks.

[0008] The battery mounted under the floor of the motor vehicle may also be exposed in the event of an impact to the vehicle. The battery must be protected to avoid damage in the event of an impact to the motor vehicle.

[0009] One of the aims of the invention is to propose a support structure for a motor vehicle battery assembly that can receive battery elements while forming a compact, lightweight and strong assembly. To this end, the invention proposes a support structure for a motor vehicle battery assembly comprising battery elements supported by the support structure, the support structure comprising two side walls defining transversely between them a receiving housing for receiving the battery elements, and a protective panel arranged under the housing, the protective panel comprising a protective plate or several superimposed protective plates, at least one protective plate comprising a central region extending under the housing and two lateral regions projecting laterally relative to the side walls of the housing, at least one of the lateral regions being provided with ribs.

[0010] The central region of each skid plate extending under the housing helps protect the battery cells from impacts from objects passing under the vehicle.

[0011] Each ribbed lateral region of a protective plate projecting laterally relative to a side wall of the housing forms an energy absorption zone of the protective plate, in particular in the event of a side impact suffered by the motor vehicle.

[0012] Indeed, an object impacting the motor vehicle laterally on the side of the ribbed lateral region encounters this ribbed lateral region before reaching the adjacent side wall of the housing, and the ribbed lateral region deforms by absorbing at least part of the energy of the impact before the object can reach the side wall of the housing.

[0013] The presence of ribs in the ribbed side region increases the deformation resistance of the ribbed side region and thus dissipates much of the impact energy before the object can reach the side wall of the housing.

[0014] The protective panel formed by the protective plate(s) thus provides protection under the housing and on the sides of the housing, which provides effective protection while preserving the compactness and lightness of the support structure, and those of the battery assembly formed by the battery and its support structure.

[0015] In particular embodiments, the support structure comprises one or more of the following optional features, taken individually or in any technically possible combination:

[0016] - the ribs of each ribbed lateral region are transversely elongated;

[0017] - the ribs of each ribbed lateral region are distributed longitudinally along the ribbed lateral region; - the ribs of at least one ribbed lateral region include ribs extending to a lateral edge of the lateral region;

[0018] - the ribs of at least one ribbed side region include one or more ribs having a variable height along the rib;

[0019] - the ribs of at least one ribbed side region include one or more ribs having a height increasing towards a side edge bordering the ribbed side region;

[0020] - the ribs of at least one ribbed side region include at least one rib extending into the central region of the protective plate to which said ribbed side region belongs;

[0021] - the ribs of at least one ribbed lateral region include one or more through ribs extending into the other lateral region of the protective plate to which said ribbed lateral region belongs, passing through the central region of said protective plate;

[0022] - the ribs of at least one ribbed lateral region include at least one rib extending into the other lateral region through the central region and having a height increasing in each lateral region towards the lateral edge bordering this lateral region;

[0023] - the ribs of at least one ribbed side region include at least one rib extending only in the ribbed side region;

[0024] - the protective panel comprises several superimposed protective plates including a first protective plate and a second protective plate, the lateral regions of the first protective plate being ribbed lateral regions and / or the lateral regions of the second protective plate being ribbed lateral regions;

[0025] - the structure comprises stiffening boxes delimited between the first protective plate and the second protective plate, in particular between the lateral regions of the first protective plate and the lateral regions of the second protective plate;

[0026] - each stiffening box is delimited by a rib of the first protective plate and / or a rib of the second protective plate;

[0027] - at least one stiffening box extends transversely over the entire width of the first protective plate and the second protective plate;

[0028] - each protective plate is made of metal, plastic material or composite material comprising a matrix reinforced by reinforcing elements, for example reinforcing fibers; - at least one or each protective plate is made of steel, in particular stainless steel or coated steel, or aluminum;

[0029] - the support structure comprises at least one reinforcing beam arranged on the protective panel, between the protective panel and the housing.

[0030] The invention also relates to a battery assembly comprising a support structure as defined above and battery cells received in the housing.

[0031] The invention also relates to an assembly comprising two side members of a vehicle chassis and a support structure as defined above, the housing being located between the two side members, the lateral regions of the protective plate(s) preferably being fixed to the side members, in particular under the side members.

[0032] The invention also relates to a motor vehicle comprising a chassis having two side members and a support structure as defined above or a battery assembly as defined above, the housing being located between the two side members, the lateral regions of the protective plate(s) preferably being fixed to the side members, in particular under the side members.

[0033] The invention and its advantages will be better understood upon reading the following description, given solely as a non-limiting example, and made with reference to the appended drawings, in which:

[0034] - Figure 1 is a cross-sectional view of a battery assembly installed under a chassis of a motor vehicle;

[0035] - Figure 2 is an assembled perspective view of a support structure of the battery assembly of Figure 1;

[0036] - Figure 3 is an exploded perspective view of the support structure of the battery assembly of Figure 1;

[0037] - Figure 4 is a perspective view of a detail of the support structure of the battery assembly of Figure 1;

[0038] - Figure 5 is a perspective view of a protective panel of the support structure;

[0039] - Figure 6 is a perspective view of a first protection plate of the protection panel of Figure 5;

[0040] - Figure 7 is a perspective view of a second protection plate of the protection panel of Figure 5;

[0041] - Figure 8 is a sectional view of a detail of the protection panel, the first protection plate and the second protection plate being assembled.

[0042] As illustrated in Figure 1, a motor vehicle 10 is equipped with a battery assembly 12 fixed under a floor 14 of a chassis 16 of the motor vehicle 10. In the remainder of the description, unless otherwise stipulated, the terms “longitudinal”, “transverse”, “horizontal”, “vertical”, “top” and “bottom” are used with reference to the usual orthogonal reference system for motor vehicles comprising a longitudinal axis X directed horizontally from rear to front, a transverse axis Y directed horizontally from right to left and a vertical axis Z directed from bottom to top.

[0043] The chassis 16 comprises two longitudinally extending side members 18 spaced transversely from each other. The two side members 18 define the lateral limits of the lower part of the chassis 16 of the motor vehicle 10.

[0044] The floor 14 extends transversely between the two side members 18. The passenger compartment (not shown) of the motor vehicle 10 is located above the floor 14.

[0045] The battery assembly 12 comprises battery cells 20 supported by a support structure 22 defining a housing 24 for receiving the battery cells 20.

[0046] Each battery element (or "battery cell" or "battery accumulator") is capable of storing electrical energy and restoring the stored electrical energy. Each battery element is, for example, an electrochemical battery element, i.e. capable of storing the electrical energy received in the form of chemical energy and then restoring electrical energy from the chemical energy.

[0047] The battery elements 20 are for example arranged in the housing 24 by being grouped into battery modules 26, each battery module 26 grouping several battery elements 20 attached together and possibly electrically connected to each other.

[0048] The battery modules 26 are for example arranged in the housing 24 in a plurality of rows distributed longitudinally in the housing 24. Each row comprises for example two battery modules 26. A row of battery modules 26 is visible in Figure 1.

[0049] Preferably, the battery assembly 12 comprises a cooling system (not shown) configured to cool the battery elements 20, comprising for example heat exchange plates and / or conduits for the circulation of a cooling fluid, and / or electrical wiring (not shown) for the electrical connection of the battery elements 20 to each other and to a battery management system (or BMS) configured to control the battery.

[0050] As seen in Figures 2 and 3, the support structure 22 comprises a peripheral wall 28 delimiting the housing 24. The peripheral wall 28 comprises two side walls 30 delimiting the housing 24 transversely between them. Each side wall 30 extends longitudinally.

[0051] Preferably, the support structure 22 comprises two transverse walls 32 extending transversely between the two side walls 30, delimiting the housing 24 longitudinally therebetween. The two transverse walls 32 are spaced apart longitudinally.

[0052] The peripheral wall 28 defines, for example, a peripheral frame framing the housing 24.

[0053] The peripheral wall 28 has, for example, a generally rectangular shape when viewed from above, two opposite parallel sides being defined by the side walls 30 and two other opposite parallel sides being defined by the transverse walls 32.

[0054] The support structure 22 optionally includes a bottom wall or lower wall 34, the peripheral wall 28 extending upwardly from edges of the lower wall 34. The side walls 30 extend upwardly from opposite longitudinal edges of the lower wall 34 and the transverse walls 32 extend upwardly from opposite transverse edges of the lower wall 34. The lower wall 34 delimits the housing 24 below.

[0055] The bottom wall 34 and the peripheral wall 28 together form a tray 36 whose bottom is formed by the bottom wall 34, the peripheral wall 28 extending upwards from the bottom wall 34.

[0056] The tray 36 is for example made from a single piece of material, for example metal, plastic material or composite material comprising a plastic matrix reinforced with reinforcing elements, in particular reinforcing fibers.

[0057] In examples, the tray 36 is made in a single piece by shaping a metal sheet, for example by folding and / or stamping.

[0058] The upper edge of the peripheral wall 28 defines an upper opening 38 of the tray 36. The upper opening 38 allows the insertion of the battery elements 20 or the battery modules 26 into the housing 24.

[0059] The support structure 22 optionally comprises one or more transverse reinforcements 40. Each transverse reinforcement 40 extends transversely between the two side walls 30. Each transverse reinforcement 40 is transversely elongated. Each transverse reinforcement 40 extends from one side wall 30 to the other while being fixed to the side walls 30. Each end 40A of the transverse reinforcement 40 is fixed to a respective side wall 30. Each transverse reinforcement 40 is for example obtained by shaping a metal sheet, in particular a steel sheet, preferably stainless steel or coated steel, or aluminum.

[0060] Shaping includes, for example, cutting, bending, and / or stamping the sheet metal. Other manufacturing techniques may be used depending on the desired shape for the transverse reinforcement 40.

[0061] As visible in Figure 3, each transverse reinforcement 40 has, for example, in section in a plane perpendicular to the direction of extension of the transverse reinforcement 40, a “U”-shaped section comprising two wings 42 connected by a central core 44.

[0062] Each transverse reinforcement 40 is for example provided, at each of its ends 40A, with one or more fixing lugs 46A for fixing said end 40A to a longitudinal wall 30, for example by screwing and / or welding.

[0063] In the case of a transverse reinforcement 40 with a “U” shaped section, each fixing lug 46A is obtained for example by folding the wing 42, preferably towards the outside of the transverse reinforcement 40, i.e. on the side opposite the other wing 42.

[0064] Each transverse reinforcement 40 is for example provided, on an edge of each wing 42 opposite the core 44, with one or more fixing edges 46B for fixing the transverse reinforcement 40 to the lower wall 34, for example by screwing and / or welding.

[0065] In the case of a transverse reinforcement 40 with a “U” shaped section, each fixing edge 46B is obtained for example by folding the wing 42, preferably towards the outside of the transverse reinforcement 40, i.e. on the side opposite the other wing 42.

[0066] Each transverse reinforcement 40 is for example obtained by cutting and bending a metal sheet. A transverse reinforcement 40 with a “U”-shaped section provides effective reinforcement while being easy and economical to manufacture, in particular by cutting and / or bending a metal sheet.

[0067] In other examples, a transverse reinforcement 40 comprises a different shape, for example with an “H” section.

[0068] The support structure 22 comprises a transverse reinforcement 40 or several transverse reinforcements 40 distributed longitudinally in the housing 24.

[0069] As illustrated in Figures 2 and 3, the support structure 22 comprises two transverse reinforcements 40. In variations, the support structure 22 comprises a single transverse reinforcement 40 or more than two transverse reinforcements 40.

[0070] In examples, the transverse reinforcement(s) 40 subdivide the housing 24 into compartments, each compartment receiving one or more battery elements 20 or one or more battery modules 26. As visible in Figure 1, the support structure 22 optionally comprises a cover 48 closing the upper opening 38 of the container 36. The cover 48 is for example in the form of a plate, preferably metallic.

[0071] Advantageously, the cover 48 closes the container 36 in a sealed manner. The support structure 22 comprises, for example, a peripheral seal (not shown) interposed between the upper edge of the peripheral wall 28 and the cover 48.

[0072] The support structure 22 comprises a protective panel 50 extending under the housing 24 and projecting laterally relative to the side walls 30 of the housing 24.

[0073] The protective panel 50 preferably extends along a horizontal plane, i.e. a plane defined by the longitudinal axis X and the transverse axis Y.

[0074] The protective panel 50 comprises a central zone 50A located under the housing 24 and two lateral zones 50B, each lateral zone 50B projecting laterally outwards relative to a respective lateral wall 30 of the housing 24.

[0075] The two lateral zones 50B of the protective panel 50 project laterally relative to the side walls 30 of the housing 24.

[0076] The protective panel 50 has the function of protecting the housing 24 against objects which could penetrate into the housing 24 from below and against the intrusion of objects laterally, in the event of a side impact suffered by the motor vehicle 2.

[0077] The lateral zones 50B projecting laterally relative to the side walls 30 define energy absorption zones in the event of a lateral impact suffered by the motor vehicle 10.

[0078] The protective panel 50 comprises a protective plate 52, 54 or several superimposed protective plates 52, 54, in particular two superimposed protective plates 52, 54.

[0079] Each protective plate 52, 54 comprises a central region 52A, 54A located under the housing 24 and two lateral regions 52B, 54B projecting laterally outwards relative to the side walls 30 of the housing 24.

[0080] The central region 52A, 54A of a protection plate 52, 54 is located in the central area 50A of the protection panel 50 and each lateral region 52A, 54A of a protection plate 52, 54 is located in a lateral area 50B of the protection panel 50. The central region 52A, 54A of each protection plate 52, 54 extends under the housing 24 between the two side walls 30 and each lateral region 52B, 54B of the protection plate 52, 54 extends transversely from the central region 52A, 54A beyond a side wall 30, each lateral region 52B, 54B extending laterally beyond a respective side wall 30.

[0081] Each lateral region 52B, 54B of each protection plate 52, 54 is bordered by a lateral edge 52C, 54C of the protection plate 52, 54.

[0082] Each lateral region 52B, 54B has, for example, a width equal to or greater than 30 mm, in particular equal to or greater than 40 mm, for example equal to or greater than 41 mm.

[0083] The width of each lateral region 52B, 54B of a protection plate 52, 54 is taken between the lower edge of the adjacent side wall 30 and the lateral edge 52C, 54C of the protection plate 54 bordering this lateral region 52B, 54B.

[0084] In examples, at least one or each protective plate 52, 54 is metallic. Each protective plate 52, 54 is made, for example, of steel, in particular stainless steel or coated steel, or aluminum.

[0085] Alternatively, at least one or each protective plate 52, 54 is made of a plastic material or of a composite material comprising a matrix made of plastic material reinforced with reinforcing elements, in particular reinforcing fibers.

[0086] In particular examples, the protective panel 50 comprises at least one metal protective plate 52, 54 and at least one protective plate 52, 54 made of a plastic material or of a composite material comprising a matrix made of plastic material reinforced with reinforcing elements, in particular reinforcing fibers.

[0087] Each protective plate 52, 54 is obtained for example by shaping a metal sheet, for example by stamping and / or folding.

[0088] At least one protection plate 52, 54 is ribbed, each ribbed protection plate 52, 54 being provided with ribs.

[0089] Each ribbed protective plate 52, 54 is for example provided with transverse ribs, i.e. elongated transversely.

[0090] Each rib of a ribbed protective plate 52, 54 is formed for example by a fold formed in the protective plate 52, 54, for example by folding and / or stamping and / or profiling the protective plate 52, 54.

[0091] At least one lateral region 52B, 54B is ribbed. Each ribbed lateral region 52B, 54B is provided with a plurality of ribs formed in the protective plate 52, 54, the ribs preferably being transverse, i.e. transversely elongated.

[0092] Transverse ribs in a lateral region 52B, 54B increase its resistance to crushing in the transverse direction, and allow significant energy absorption when such crushing occurs.

[0093] Preferably, each ribbed lateral region 52B, 54C comprises a plurality of ribs distributed longitudinally along the lateral region 52B, 54C.

[0094] This makes it possible to increase the energy absorption capacities of the ribbed lateral region 52B, 52C over a significant longitudinal extent, preferably equal to the length of the housing 24, taken for example between transverse walls 32 delimiting the housing 24 longitudinally.

[0095] Preferably, at least one ribbed lateral region 52B, 54B comprises at least one rib extending to a lateral edge 52C, 54C bordering said lateral region 52B, 54B.

[0096] The extension of a rib to the lateral edge 52C, 54C of the lateral region 52B, 54B makes it possible to maximize the energy absorption capacity of the lateral region 52B, 52C in the event of deformation.

[0097] Advantageously, at least one rib extending in a ribbed lateral region 52B, 54B has a height increasing towards the lateral edge 52C, 54C bordering this lateral region 52C, 54C.

[0098] In exemplary embodiments, at least one rib of a ribbed lateral region 52B, 54B of a protective plate 52, 54 extends only in said lateral region 52B, 54B. Such a rib does not extend into the central region 52A, 54A of the protective plate 52, 54.

[0099] Preferably, at least one rib of a ribbed lateral region 52B, 54B of a protective plate 52, 54 is a through rib, each through rib extending transversely in the two lateral regions 52B, 54B of the protective plate 52, 54 passing through the central region 52A, 54A of the protective plate 52, 54. This makes it possible to increase the resistance of the protective plate 52 and its capacity to dissipate energy in the event of an impact.

[0100] At least one or each through rib of a protective plate 52, 54 extends for example from one lateral edge 52C, 54C to the other of the protective plate 52, 54.

[0101] In examples, the height of at least one through rib of a protection plate 52, 54 varies along the through rib, the through rib preferably having in each lateral region 52, B, 54B a height greater than the height of the through rib in the central region 52A, 54A.

[0102] A variation in the height of a through rib makes it possible to provide a rib of great length with a reduction in the thickness of the protection panel 50 in a central zone 50A located under the housing 24 to limit the overall vertical size of the support structure 22 and an increase in the thickness of the protection panel 50 in lateral zones 50B of the protection panel 50 to increase the strength and the energy dissipation capacity of these lateral zones 50B.

[0103] In exemplary embodiments, the central region 52A, 54A of at least one protective plate 52, 54 comprises at least one flat area, i.e. devoid of ribs.

[0104] In exemplary embodiments, the lateral regions 52B, 54B of at least one or each protective plate 52, 54 are at least partially raised relative to the central region 52A, 54B of the protective plate 52, 54.

[0105] Advantageously, the lateral regions 52B, 54B of at least one or each protective plate 52, 54 extend laterally from the central region 52A, 54A of the protective plate 52, 54, rising progressively, so that the lateral edges 52C, 54C of the protective plate 52, 54 are raised relative to the central region 52A, 54A of the protective plate 52, 54.

[0106] Raising the lateral regions 52B, 54B relative to the central region 52A, 54A makes it possible to lower the central region 52A, 54A to increase the height of the housing 24 while positioning the lateral regions 52B, 54B higher or increasing the height of the lateral zones 50B of the protective panel 50 formed by superimposing protective plates 52, 54, for better absorption of lateral impacts.

[0107] Advantageously, as in the example illustrated, the protection panel 50 comprises a first protection plate 52 and a second protection plate 54 superimposed.

[0108] The second protective plate 54 is for example arranged on the first protective plate 52.

[0109] The first protection plate 52 and the second protection plate 54 are preferably fixed together, for example by screwing, bolting, riveting, welding and / or gluing.

[0110] The first protective plate 52 and the second protective plate 54 have, for example, different thicknesses. The first protective plate 52 is in particular thicker than the second protective plate 54. Alternatively, the first protective plate 52 is thinner than the second protective plate 54. In other examples, the first protective plate 52 and the second plate have the same thickness.

[0111] As seen in Figure 4, the protective panel 50 advantageously comprises stiffening boxes 60 defined between the first protective plate 52 and the second protective plate 54.

[0112] Each stiffening box 60 (or stiffening chamber) is in the form of a cavity defined between the first protective plate 52 and the second protective plate 54.

[0113] Each stiffening box 60 is delimited for example by a transverse rib of the first protective plate 52 and / or a transverse rib of the second protective plate 54.

[0114] Each stiffening box 60 is, for example, elongated transversely.

[0115] Each stiffening box 60 has a lower box wall 62 defined by the first protective plate 52 and an upper box wall 64 defined by the second protective wall 54.

[0116] The height of each stiffening box 60 is the vertical distance between the lower box wall 62 and the upper box wall 64.

[0117] In exemplary embodiments, at least one stiffening box 60 has a height which varies along the stiffening box 60, in particular in the lateral zones 50B of the protective plate 50.

[0118] In exemplary embodiments, at least one stiffening box 60 has a height which varies along the stiffening box 60, being constant in the central zone 50A and variable in each lateral zone 50B of the protective plate 50, the height increasing in each lateral zone 50B or decreasing in each lateral zone 50B.

[0119] In exemplary embodiments, at least one stiffening box 60 has, in one or each lateral zone 50B, a horizontal lower box wall 62 and an upper box wall 64 varying progressively towards the adjacent lateral edge of the protective panel 50 so that the height of the stiffening box 60 varies progressively towards the lateral edge 58.

[0120] In examples, at least one stiffening box 60 extends in the central zone 50A and one or each lateral zone 50B with a horizontal lower box wall 62 and a horizontal upper box wall 64 in the central zone 50A and extending, in each lateral zone 50B, gradually rising, such that the height of the stiffening box 60 gradually increases towards a lateral edge bordering the lateral zone 50B.

[0121] In examples, one or each of the first protection plate 52 and the second protection plate 54 is provided with transverse ribs, particularly in at least one lateral region 52B, 54B, preferably in each lateral region 52B, 54B.

[0122] As illustrated in Figures 3 and 6, the first protective plate 52 comprises for example lateral ribs 76 extending transversely in the lateral regions 52B (without extending into the central region 52A) and / or through ribs 78 extending transversely in the two lateral regions 52B passing through the central region 52A.

[0123] One or more lateral ribs 76 of the first protection plate 52 have a constant height along the lateral rib 76 and / or one or more lateral ribs 76 of the first protection plate 52 have a variable height along the lateral rib 76, preferably an increasing height towards the lateral edge 52C bordering the corresponding lateral region 52B.

[0124] One or more through ribs 78 of the first protective plate 52 have a constant height along the through rib 78 and / or one or more through ribs 78 of the first protective plate 52 have a variable height along the through rib 78, preferably a height that increases in each lateral region 52B towards the adjacent lateral edge 52C. The height of each through rib 78 is preferably constant in the central region 54.

[0125] As illustrated in Figures 3, 5 and 7, the second protection plate 54 comprises through ribs 84 extending transversely in the two lateral regions 54B of the second protection plate 54 passing through the central region 54A of the second protection plate 54, preferably from one lateral edge 54C to the other of the second protection plate 54.

[0126] The second protective plate 54 has a longitudinally corrugated or crenellated shape with alternating ribs 84 and hollows defined between the ribs 84.

[0127] Ribs of a protective plate 52, 54 may have varying widths. As illustrated in Figures 3 and 6, the through ribs 78 of the first protective plate 54 have an alternation of wide through ribs 78 and narrow through ribs 78. Ribs of a protective plate 52, 54 may be formed at the tops of other ribs. As illustrated in Figures 3 and 6, the lateral ribs 76 are formed at the tops of through ribs 78, in particular wide through ribs.

[0128] The ribs of the first protective plate 52 and / or of the second protective plate 54 are positioned relative to each other in such a way that each stiffening box 60 is for example delimited vertically between a rib of the first protective plate 52 and a hollow delimited between two ribs of the second protective plate 54 or between a hollow delimited between two ribs of the first protective plate 52 and a rib of the second protective plate 54 or between a hollow delimited between two ribs of the first protective plate 52 and a hollow delimited between two ribs of the second protective plate 54 or between a rib of the first protective plate 52 and a rib of the second protective plate 54.

[0129] As visible in Figure 4, in exemplary embodiments, ribs of the first protective plate 52 are opposite and in contact with the bottom of hollows defined between ribs of the second protective plate 54.

[0130] Each stiffening box 60 is defined between a hollow defined between two ribs 78 of the first protective plate 52, the bottom of which defines the lower box wall 62, and a rib 84 of the second protective plate 54, the top of which forms the upper box wall 64.

[0131] This arrangement makes it possible to form 60 stiffening boxes with a significant height.

[0132] Advantageously, in each lateral zone 50B of the protection panel 50, at least one or each contact zone 88 between the first protection plate 52 and the second protection plate 54 rises progressively towards the lateral edge 56C of the lateral region 56.

[0133] In particular, in each lateral zone 50B, at least one or each contact zone 88 between the top of a rib 78 of the first protective plate 52 and a hollow defined between two ribs 84 of the second protective plate 54 rises progressively towards the lateral edges 52C, 54C of the first protective plate 52 and of the second protective plate 54.

[0134] The elevation of the contact zones 88 in the direction of the lateral edges 52C, 54C makes it possible to increase the height of the stiffening boxes 60 in each lateral zone 50B by distributing the variation in height between the first protection plate 52 and the second protection plate 54, which limits the necessary deformations of the first protection plate 52 and of the second protection plate 54 in the case where these are obtained by deformations of flat sheets, for example by stamping and / or flat sheets.

[0135] Advantageously, the protective panel 50 is provided with fixing orifices 90 for fixing the protective panel to the side members 18 and / or to the side walls 30 and / or to the transverse walls 32 and / or, when present, to the lower wall 34, for example using fixing members 92 such as screws, bolts or rivets.

[0136] Preferably, each fastening hole 90 extends through a contact area between the first protective plate 52 and the second protective plate 54. This makes it possible to avoid vertical crushing of the protective panel 50 during assembly, as could happen if the fastening member 90 passed through a hollow area of ​​the protective panel 50.

[0137] Advantageously, the protective panel 50 is provided with fixing orifices 90, in each lateral zone 50, for fixing the lateral zone 50 to a spar 18. The lateral zone 50 is preferably applied against a lower surface of the spar 18 and fixed thereto using one or more fixing members 92.

[0138] In exemplary embodiments, as illustrated in Figure 4, the first protective plate 52 has, for example, along the lateral edge 52C of each lateral region 52B, contact zones with the second protective plate 54, in particular with the top of a rib 84 of the second protective plate 54, a fixing orifice 90 passing through the protective panel 50 by passing through the contact zone.

[0139] In examples, as illustrated in Figure 4, the top of at least one rib of the first cover plate 52 is in contact with the top of a rib of the second cover plate 54, a fixing hole 90 being provided in this contact area, through the rib of the first cover plate 52 and the rib 84 of the second cover plate 54.

[0140] In examples, as illustrated in Figure 4, the top of at least one rib 76 overlying another rib 78 of the first protective plate 52 is in contact with the top of a rib of the second protective plate 54, a fixing hole 90 being provided in this contact area, through the rib of the first protective plate 52 and the rib 84 of the second protective plate 54.

[0141] In particular examples, as illustrated in Figure 4, the top of at least one lateral rib 76 surmounting a through rib 78 of the first protective plate 52 is in contact with the top of a rib of the second protective plate 54, in particular a through rib 84 of the second protective plate 54, a fixing orifice 90 being provided in this contact zone, through the rib of the first protective plate 52 and the rib 84 of the second protective plate 54.

[0142] As visible in Figure 3, the support structure 22 optionally comprises a reinforcing spar 96 attached to the central region 50A of the protective panel 50, between the two lateral zones 50C.

[0143] The reinforcing spar 96 is for example arranged on an upper surface of the protection panel 750, in particular between the protection panel 50 and a lower wall 34 extending transversely between lower edges of the two side walls 30 of the housing 24.

[0144] The reinforcing beam 96 makes it possible to stiffen the support structure 22 between the two lateral zones 50 which are fixed to the beams 18 of the chassis 16 of the motor vehicle 10.

[0145] As illustrated in Figure 8 which represents a partial section of the protection panel 50, in examples, at least one stiffening box 60 is delimited between a hollow between ribs 78 of the first protection plate 52 and a through rib 84 of the second protection plate 54.

[0146] The stiffening box 60 has, for example, a constant height in the central zone 50B and an increasing height in each lateral zone 50B due to the fact that the rib 84 of the second plate 52 has an increasing height in the lateral region 52B, while the bottom of the hollow of the first protective plate is horizontal.

[0147] In operation, the battery assembly 12 is mounted under the floor 14 of the motor vehicle 10. The housing 24 is received between the side members 18 of the chassis 16, the lateral zones of the protection panel 52 projecting laterally relative to the side walls 30 of the housing 24 and being fixed to the side members 18, each lateral zone 50B being fixed to a respective side member 18, preferably under it.

[0148] The protective panel 50 protects the housing 24 and the battery elements 20 received therein from the intrusion of any object from below the motor vehicle 10. Such objects could be stones present on the road or road development elements, such as fixed or retractable bollards, for example in the event of a false maneuver by the driver.

[0149] Furthermore, the lateral regions 52B, 54B of each protective plate 52, 54 form energy absorption zones located transversely between the side members 18 and the housing 24. The lateral regions 52B, 54B protect the housing 24 and the battery elements 20 that it contains in the event of a lateral impact suffered by the motor vehicle 10. Indeed, in the event of a lateral impact of an object against a side member 18 causing the side member 18 to be pushed towards the inside of the vehicle, the deformation of the side member 18 is accompanied by a deformation of the corresponding lateral region 52B, 54B of each protective plate 52, 54 which dissipates energy and participates in absorbing the energy of the impact. The presence of ribs in one or more lateral regions 52B, 54B of one or more protective plates 52, 54 makes it possible to increase the energy absorption capacity.

[0150] The provision of lateral regions 52B, 54B of one or more protective plates 52, 54 projecting laterally, preferably extending to the side members 18, makes it possible to form energy absorption zones integrated into the protective panel 50 without having to add energy absorption devices. This makes it possible to limit the manufacturing cost of the support structure 22 and to preserve the compactness and lightness of the support structure 22 compared to a support structure which would include added energy absorption devices in addition to a protective plate.

[0151] The provision, in a ribbed lateral region 52B, 54B of a protective plate 52, 54, of ribs of increasing height towards a lateral edge 52C, 54C bordering the lateral region 52B, 54B, makes it possible to increase the energy absorption capacity of the lateral region 52B, 54B in the areas mainly impacted by a lateral impact, while limiting the height of the support structure 22 in the area of ​​the housing 24 receiving the battery elements 20.

[0152] This facilitates the integration of the battery assembly 12 into a motor vehicle 10, in particular under the floor 14 of the motor vehicle 10.

[0153] The invention is not limited to the exemplary embodiments and variants described above with reference to Figures 1 to 8. Other exemplary embodiments and other variants are conceivable.

[0154] In particular, the cover 48 is optional. In exemplary embodiments, the peripheral wall 28 is fixed directly under the floor 14 of the chassis of the motor vehicle 10, without the interposition of a cover 48. If necessary, a seal is created between the upper edge of the peripheral wall 28 and the floor 14, for example by interposing a seal between them.

[0155] Furthermore, when the protection panel 50 comprises a first protection plate 52 and a second protection plate 54, the lateral regions 52B, 54B of the two protection plates 52, 54 are not necessarily ribbed.

[0156] It is possible to provide one of the two protective plates 52, 54 with ribbed lateral regions 52B, 54B and the other with flat lateral regions 52B, 54B. Such a configuration also makes it possible to define stiffening boxes 60 in the lateral zones 50B of the protective panel 50.

[0157] In a particular example, one of the two protection plates 52, 54 is flat, the other being ribbed in one or each of its lateral regions 52B, 54B, and optionally also in its central region 52A, 54A.

[0158] As indicated previously, in examples, at least one or each protection plate 52, 54 is made of steel, in particular from a shaped steel sheet, in particular by stamping and / or profiling.

[0159] In examples, at least one or each protective plate 52, 54 made from a steel sheet is made from a steel having a composition having a chromium (Cr) content equal to or greater than 16.0% by weight and generally less than or equal to 20.0% by weight.

[0160] A steel having a composition having a chromium content equal to or greater than 16.0% by weight provides a skid plate 52, 54, and the support structure incorporating the skid plate 52, 54, with good corrosion resistance, which is important when the support structure is positioned under a vehicle chassis.

[0161] Generally speaking, the composition of the steel preferably includes, the contents being expressed in mass percentages:

[0162] C < 0.15%

[0163] Mn < 7.5%

[0164] P < 0.045%

[0165] S < 0.03%

[0166] If < 1%

[0167] 16.0% < Cr < 28.0%

[0168] 3.5% < Ni < 10.5%

[0169] N < 0.25%, the remainder being iron and unavoidable impurities.

[0170] In a particular embodiment, the steel of at least one or each protective plate 52, 54 formed from a steel sheet is a type 201 L steel according to the AISI standard, the composition of which generally contains, the contents being expressed as a mass percentage:

[0171] C < 0.03%

[0172] 5.5% < Mn <7.5%

[0173] P < 0.045%

[0174] S < 0.03% If < 0.75%

[0175] 16.0% < Cr < 18.0%

[0176] 3.5% < Ni < 5.5%

[0177] N < 0.25%, the remainder being iron and unavoidable impurities.

[0178] In another particular embodiment, the steel of at least one or each protective plate 52, 54 formed from a steel sheet is a type 301 steel according to the AISI standard, the composition of which generally contains, the contents being expressed as a mass percentage:

[0179] C < 0.15%

[0180] Mn < 2.0%

[0181] P < 0.045%

[0182] S < 0.03%

[0183] If < 1.0%

[0184] 16.0% < Cr < 18.0%

[0185] 6.0% < Ni < 8.0%

[0186] N < 0.1%, the remainder being iron and impurities.

[0187] In another particular embodiment, the steel of at least one or each protective plate 52, 54 formed from a steel sheet is a type 304 steel according to the AISI standard, the composition of which generally contains, the contents being expressed as a mass percentage:

[0188] C < 0.08%

[0189] Mn < 2.0%

[0190] P < 0.045%

[0191] S < 0.03%

[0192] If < 0.75%

[0193] 18.0% < Cr < 20.0%

[0194] 8.0% < Ni < 10.5%

[0195] N < 0.1%, the remainder being iron and unavoidable impurities.

[0196] Preferably, the steel of at least one or each protective plate 52, 54 formed from a steel sheet has, before shaping the protective plate 52, 54, a microstructure comprising, in volume fraction, more than 70% of austenitic phase and / or less than 30% of martensitic and / or ferritic phase. Preferably, the steel of at least one or each protective plate 52, 54 formed from a steel sheet has, before shaping the protective plate 52, 54, an elongation at break equal to or greater than 40%, a tensile strength (Rm) of at least 515 MPa and / or a conventional yield strength (Rp0.2) of at least 170 MPa.

[0197] According to one embodiment, the steel being a 201 L steel, the steel has, before shaping the protective plate 52, 54, an elongation at break equal to or greater than 40%, a tensile strength (Rm) of at least 655 MPa and / or a conventional elastic limit (Rp0.2) of at least 260 MPa.

[0198] According to another embodiment, the steel being a 301 steel, the steel has, before shaping the protective plate 52, 54, an elongation at break equal to or greater than 40%, a tensile strength (Rm) of at least 515 MPa and / or a conventional elastic limit (Rp0.2) of at least 205 MPa.

[0199] According to another embodiment, the steel being a 304 steel, the steel has, before shaping the protective plate 52, 54, an elongation at break equal to or greater than 40%, a tensile strength (Rm) of at least 515 MPa and / or a conventional elastic limit (Rp0.2) of at least 170 MPa.

[0200] Preferably, the steel of at least one or each protective plate 52, 54 formed from a steel sheet has, after shaping of the protective plate 52, 54 and, preferably, at any location of the protective plate 52, 54, a residual elongation at break equal to or greater than 10%.

[0201] The microstructure and mechanical characteristics of the steel sheet before and after forming the steel sheet (elongation at break, tensile strength and conventional yield strength) enable the support structure to support a battery assembly while being able to dissipate the energy of an impact, in particular by each ribbed lateral region of a protective plate projecting laterally relative to the side walls of the battery deception housing and enabling a shock absorption zone to be defined.

[0202] Steels 301, 304 and 201 L have a chromium content equal to or greater than 16.0% by weight and are particularly suitable for the production of protective plates 52, 54 by forming a sheet, with the microstructure and mechanical properties indicated above.

Claims

CLAIMS 1. Support structure for a motor vehicle battery assembly comprising battery elements (20) supported by the support structure, the support structure comprising two side walls (30) delimiting transversely between them a housing (24) for receiving the battery elements, and a protective panel (50) arranged under the housing, the protective panel (50) comprising a protective plate or several superimposed protective plates (52, 54), at least one protective plate (52, 54) comprising a central region (52A, 54A) extending under the housing and two lateral regions (52B, 54B) projecting laterally relative to the side walls (30) of the housing (24), at least one of the lateral regions (52B, 54B) being provided with ribs (76, 78, 84).

2. Support structure according to claim 1, in which the ribs of each ribbed side region (52B, 54B) are transversely elongated.

3. A support structure according to claim 1 or claim 2, wherein the ribs of each ribbed side region (52B, 54B) are distributed longitudinally along the ribbed side region (52B, 54B).

4. A support structure according to any preceding claim, wherein the ribs of at least one ribbed side region (52B, 54B) include ribs extending to a side edge of the ribbed side region (52B, 54B).

5. A support structure according to any preceding claim, wherein the ribs of at least one ribbed side region (52B, 54B) include one or more ribs having a variable height along the rib.

6. A support structure according to any preceding claim, wherein the ribs of at least one ribbed side region (52B, 54B) include one or more ribs having a height increasing towards a side edge bordering the ribbed side region.

7. Support structure according to any one of the preceding claims, wherein the ribs of at least one ribbed lateral region (52B, 54B) include at least one rib extending into the central region (52A, 54A) of the protective plate to which said ribbed lateral region (52B, 54B) belongs.

8. Support structure according to any one of the preceding claims, in which the ribs of at least one ribbed lateral region (52B, 54B) include one or more through ribs (78, 84) extending into the other lateral region (52B, 54B) of the protection plate (52n 54) to which said region belongs ribbed side (52B, 54B), passing through the central region (52A, 54A) of said protective plate (52, 54).

9. A support structure according to any preceding claim, wherein the ribs of at least one ribbed side region (52B, 54B) include at least one rib extending into the other side region through the central region and having a height increasing in each ribbed side region (52B, 54B) towards the side edge bordering that ribbed side region (52B, 54B).

10. A support structure according to any preceding claim, wherein the ribs of at least one ribbed side region (52B, 54B) include at least one rib (76) extending only in the ribbed side region (52B, 54B).

11. Support structure according to any one of the preceding claims, wherein the protection panel (50) comprises a plurality of superimposed protection plates (52, 54) comprising a first protection plate (52) and a second protection plate (54), the lateral regions (52B) of the first protection plate (52) being ribbed lateral regions (52B) and / or the lateral regions (54B) of the second protection plate (54) being ribbed lateral regions (54B).

12. Support structure according to claim 11, comprising stiffening boxes (60) delimited between the first protective plate (52) and the second protective plate (54), in particular between the lateral regions (52B) of the first protective plate (52) and the lateral regions (54B) of the second protective plate (54).

13. Support structure according to claim 12, in which each stiffening box (60) is delimited by a rib of the first protective plate (52) and / or a rib of the second protective plate (54).

14. Support structure according to any one of claims 11 to 13, in which at least one stiffening box (60) extends transversely over the entire width of the first protective plate (52) and the second protective plate (54).

15. Support structure according to any one of the preceding claims, in which each protective plate (52, 54) is made of metal, plastic material or composite material comprising a matrix reinforced by reinforcing elements, for example reinforcing fibers.

16. Support structure according to any one of the preceding claims, wherein each protection plate (52, 54) is made 17. Support structure according to any one of the preceding claims, wherein at least one or each protective plate (52, 54) is made of steel, in particular stainless steel or coated steel, or aluminum.

18. Support structure according to claim 17, wherein the steel has a composition having a chromium content equal to or greater than 16.0% by weight, in particular a content between 16.0% and 20.0%.

19. A support structure according to claim 17 or 18, wherein the steel is a 301 or 304 or 201 L steel.

20. Support structure according to any one of the preceding claims, wherein at least one or each protective plate (52, 54) is formed from a shaped steel sheet, in particular by stamping and / or profiling.

21. Support structure according to any one of claims 17 to 20, in which, the steel has, before shaping of the protective plate (52, 54), a microstructure comprising, in volume fraction, more than 70% of austenitic phase and / or less than 30% of martensitic and / or ferritic phase.

22. Support structure according to any one of claims 17 to 21, in which, before shaping the protective plate (52, 54), the steel has an elongation at break equal to or greater than 40%, a tensile strength (Rm) of at least 515 MPa and / or a conventional elastic limit (Rp0.2) of at least 170 MPa.

23. Support structure according to any one of claims 17 to 22, in which, the steel has, after shaping of the protective plate (52, 54) and, preferably, at any location of the protective plate (52, 54), an elongation at break equal to or greater than 10%.

24. Support structure according to any one of the preceding claims, comprising at least one reinforcing spar (96) arranged on the protective panel (50), between the protective panel (50) and the housing (24).

25. A battery assembly comprising a support structure (22) according to any preceding claim and battery cells (20) received in the housing (24).

26. An assembly comprising two side members (18) of a chassis (16) of a vehicle and a support structure (22) according to any one of claims 1 to 23, the housing being located between the two side members (18), the lateral regions (52B, 54B) of the protective plate(s) (52, 54) preferably being fixed to the side members (18), in particular under the side members (18).

27. Motor vehicle comprising a chassis (16) having two side members (18) and a support structure according to any one of the Claims 1 to 23 or battery assembly according to claim 25, the housing (24) being located between the two side members (18), the lateral regions (52B, 54B) of the protective plate(s) (52, 54) preferably being fixed to the side members (18), in particular under the side members (18).