AUTOMOBILE BATTERY WITH FLOOR MOUNTING POINTS LOCATED BETWEEN THE INTERNAL CROSS BEAMS OF THE BOX

Abstract

A motor vehicle traction battery comprising, within a casing, internal cross members (12) arranged along the transverse direction of the vehicle, which separate spaces receiving electrochemical cells (14), and comprising on a casing cover, battery (24) attachment points under a vehicle floor, this battery comprising at least one reinforcing plate (20) elongated along the longitudinal direction, fixed under the cover, and fixed at its ends above two nearby cross members (12), and comprising on the cover a connecting bridge (22) comprising an attachment point (24), which is fixed to the reinforcing plate (20) by passing through this cover. Figure 2

Description

Title of the invention: AUTOMOBILE BATTERY WITH FLOOR MOUNTING PLACED BETWEEN THE INTERNAL CROSS BEAMS OF THE CAISSON

[0001] The present invention relates to a motor vehicle traction battery comprising fixings to the vehicle floor arranged between the internal cross members of the battery box, as well as to a motor vehicle equipped with such a traction battery.

[0002] A known type of electric motor vehicle, presented in particular by document CN-A-112757885, includes a passenger compartment floor comprising above the crossbeams for supporting the passenger seats, and next to these crossbeams, fixings for a battery box forming a flat assembly fixed under the floor.

[0003] Reinforcing plates arranged on the floor constitute localized reinforcements of this floor, which cover both the fixings of the box and the support cross members of the seats in order to reinforce these fixings receiving the weight of the battery.

[0004] Each battery box fastener has a screw that passes through the reinforcement plate and then the floor to screw into a spacer fixed above the box, along the median axis of an internal cross member of the box separating areas housing the electrochemical electricity storage elements. The internal cross member is fixed to a lower plate closing the bottom of the box, to form a rigid assembly with the lid.

[0005] In this way, a direct and resistant connection is obtained along a vertical axis between the floor with its reinforcement plate, which is stiffened by the proximity of the seat support crossbeams, and the crossbeam in the box aligned below this fixing.

[0006] For this type of vehicle, depending on its longitudinal direction, the positioning of the internal battery cross members is imposed by the position of the fixings formed on the floor with its reinforcement plate, in connection with the seat support cross members which stiffen this area, to obtain their alignments in order to support the weight of the battery which is high.

[0007] Furthermore, since the battery box forms a rigid assembly, the mounting points of this box, located next to a floor crossmember, provide rigidity to the floor and crossmember assembly. In particular, during a significant lateral impact that deforms the side sill rail and applies pressure to the floor, which tends to tilt with its center rising, the highly rigid mounting points of the battery box maintain the floor at the level of these mountings. limiting its upward movement. In this way, the outward tilt of the seat above is reduced, which ensures better safety for the passenger in that seat.

[0008] However, this type of battery box fixing poses problems in the case of a requested evolution of the battery, including a new arrangement of the areas receiving the electrochemical cells resulting in displacements of the internal cross members, because of the necessary alignment of the fixings on these cross members.

[0009] One solution involves modifying the vehicle floor to relocate the mounting points so they align with the internal crossmembers, which can be costly. This results in two different floors to accommodate batteries depending on the old and new models, whereas the same type of floor can be used with various body styles, leading to destandardization issues that increase the complexity of the design and raise costs.

[0010] The present invention is specifically intended to avoid these problems of the prior art.

[0011] To this end, it proposes a motor vehicle traction battery comprising in a box of internal cross members arranged along the transverse direction of the vehicle, which separate spaces receiving electrochemical cells, and comprising on a box cover battery attachment points under a floor of the vehicle, this battery being notable in that it includes at least one elongated reinforcement plate along the longitudinal direction, fixed under the cover, and fixed at its ends above two nearby cross members, and in that it includes on the cover a connecting bridge comprising a fixing point, which is fixed to the reinforcement plate by passing through this cover.

[0012] One advantage of this traction battery is that each reinforcement plate connecting two parallel cross members allows the fixing points between these cross members to be offset along the plate, which gives wide possibilities for the placement of these points along the longitudinal direction of the vehicle.

[0013] In particular, it is possible to modify the arrangement of the electrochemical cells and the internal crossbeams in the battery box, while keeping the fixing points in the same locations on the floor.

[0014] It is possible to develop a traction battery of the vehicle while retaining a standard floor which is not modified, which simplifies the development of this vehicle and reduces costs.

[0015] The traction battery according to the invention may further comprise one or more of the following characteristics, which may be combined with each other.

[0016] Advantageously, the reinforcing plate has a constant cross-section comprising ribs arranged along its length.

[0017] In this case, advantageously the reinforcement plate comprises in its cross-section a central lower part having on each side a wing arranged at a higher level.

[0018] Advantageously, the reinforcement plate is fixed along its length under the cover.

[0019] Advantageously, the traction battery includes screws for fixing the cover to the internal cross members which pass through the ends of the reinforcement plate.

[0020] Advantageously, the connecting bridge has an upper face comprising a fixing point, having on two opposite sides a downward vertical face for connecting with a tab fixed above the cover.

[0021] In this case, advantageously the legs of the connecting bridge are fixed by screws to the reinforcement plate by passing through the cover.

[0022] Moreover, advantageously the downward vertical faces of the bridge are arranged along the longitudinal direction of the vehicle.

[0023] The invention also relates to an electric or hybrid motor vehicle, remarkable in that it includes a traction battery comprising any one of the preceding characteristics which is fixed under the floor of the passenger compartment.

[0024] Advantageously, the fixing point is framed on each side by a seat support cross member fixed to the top of the floor.

[0025] The invention will be better understood and other features and advantages will become more apparent upon reading the following description given by way of example, with reference to the accompanying drawings in which:

[0026] [Fig-1] is a top view of a motor vehicle traction battery according to the invention presented with the seat crossbars and without the floor;

[0027] [Fig.2] is a top view of one side of the traction battery shown without the box lid;

[0028] [Fig.3] is a cross-sectional view of the battery along a vertical plane, passing through a point of attachment; and

[0029] [Fig.4] is a perspective view showing a connecting sheet metal with its plate of reinforcement coming above the lid which is not shown.

[0030] Throughout the document the upper or top direction is relative to a vehicle placed on a horizontal ground, and the transverse direction Y is perpendicular to the longitudinal axis X of the vehicle.

[0031] Figures 1, 2, 3 and 4 show a motor vehicle traction battery comprising a lower base 18 formed by a sheet comprising a front edge 2, a rear edge 4, and a side 6 having a series of holes 8 provided for fixing under a side member 42 of the vehicle body.

[0032] The interior of the battery box has a central longitudinal passage 10, and cross members 12 following the transverse direction Y which delimit between each other on each side of the battery five equal rectangular zones containing electrochemical elements 14. An electronic control box 16 is fixed on one side of the battery above the cells 14.

[0033] On each side of the housing, an elongated reinforcement plate 20, extending along the longitudinal direction X and having ribs, is fixed above two closely spaced cross members 12 to form a bridge rigidly connected to these cross members below the cover 30. A connecting plate forming a bridge 22, positioned above the cover 30 and extending along the transverse direction Y, has ends fixed to the sides of the reinforcement plate 20 by passing through this cover. The center of the bridge 22 has a fixing point 24 under the floor of the vehicle's passenger compartment, which is aligned along the transverse fixing axis A.

[0034] The floor of the vehicle 40 is fixed on each side to a longitudinal member 42 to form a rigid assembly.

[0035] The vehicle floor 40 has, on each side of the transverse axis A, a seat crossmember 44 that receives the vehicle seats. In this way, each fixing point 24 of the box is reinforced by the proximity of the two seat crossmembers 44 to form a rigid assembly; these crossmembers also conversely provide support for the floor panel 40 next to the fixings 24.

[0036] The traction battery shown [Fig.2] replaces on the vehicle an old battery which had along the longitudinal direction X six receiving zones for the electrochemical cells 14, and had an intermediate cross member 12 arranged along the transverse fixing axis A, the fixing point 24 being directly connected to this cross member by passing through the cover of the box 30.

[0037] The reinforcement plate 20 has a constant cross-section comprising a central lower part 50 placed flat on the cross member 12, having on each side a raised wing 52 forming a Q which gives this elongated plate a strong resistance to bending between its end supports fixed on two cross members which are close together.

[0038] The reinforcement plate 20 is fixed along its full length under the cover 30 by any means, including in particular spot or continuous welding, or gluing, to form a rigid connection along the length of this plate.

[0039] After the cover 30 is placed on the battery to assemble it, at each end of the reinforcement plate 20 two screws 54 are engaged through the cover 30 and then through the two wings 52 of this plate, in order to screw each one into a wedge 56 fixed above the cross member 12 which compensates for the height of the wings.

[0040] The thickness of the reinforcement plate 20 with its ribs is included in the height of the electrical connecting bars arranged above the cells 14, which does not increase the overall size of the battery.

[0041] The bridge 22 has a constant section arranged along the transverse direction, comprising a raised central part 60 having a central boss receiving in the middle the fixing point 24, extending on each side by a substantially vertical downward face arranged along the longitudinal direction X, then by a horizontal tab 58 turned outwards from the bridge which is fixed on a wing 52 of the reinforcement plate 20 by passing through the cover 30.

[0042] In this way, a vertical connection is obtained between the battery box cross members 12 and the vehicle floor 40 via the reinforcement plate 20 and the bridge 22, which is highly rigid in the vertical direction. During a side impact, the rigid battery box retains the floor 40 at the attachment points 24, which in particular limits the upward movement of this floor that would cause the seats fixed to the seat cross members 44 located next to these points to tilt.

[0043] Furthermore, since the vertical faces of the bridge 22 are arranged along the longitudinal direction of the vehicle X, during a side impact, along the transverse direction Y, these faces can bend between their base and apex, resulting in an inclination of the bridge that prevents significant lateral energy transmission between the floor 40 and the battery compartment, and dampens part of the impact. The battery is less deformed, which protects the internal electrochemical cells 14.

[0044] Thanks to the combination of the elongated reinforcement plate 20 which connects two battery crossbars 12, fixed under the cover 30, and the bridge 22 fixed above this cover between two crossbars, a fixing point 24 can be arranged in any longitudinal position, independently of that of these crossbars.

[0045] This allows modification of the areas receiving the cells 14 with a longitudinal displacement of the cross members 12, without modifying the floor of the vehicle, which makes it possible to optimize the battery to improve in particular its mass and its energy storage capacity.

Claims

Demands

1. A motor vehicle traction battery comprising in a casing internal cross members (12) arranged along the transverse direction of the vehicle, which separate spaces receiving electrochemical cells (14), and comprising on a casing cover (30) battery attachment points (24) under a vehicle floor (40), characterized in that it comprises at least one reinforcement plate (20) elongated along the longitudinal direction, fixed under the cover (30), and fixed at its ends above two nearby cross members (12), and in that it comprises on the cover (30) a connecting bridge (22) comprising an attachment point (24), which is fixed to the reinforcement plate (20) by passing through this cover (30).

2. Traction battery according to claim 1, characterized in that the reinforcement plate (20) has a constant cross-section comprising ribs arranged along its length.

3. Traction battery according to claim 2, characterized in that the reinforcement plate (20) has in its cross-section a central lower part (50) having on each side a wing (52) arranged at a higher level.

4. Traction battery according to any one of the preceding claims, characterized in that the reinforcement plate (20) is fixed along its length under the cover (30).

5. Traction battery according to any one of the preceding claims, characterized in that it comprises screws (54) for fixing the cover (30) to the inner cross members (12) which pass through the ends of the reinforcement plate (20).

6. Traction battery according to any one of the preceding claims, characterized in that the connecting bridge (22) has an upper face (60) comprising a fixing point (24), having on two opposite sides a downward vertical face for connecting with a tab (58) fixed above the cover (30).

7. Traction battery according to claim 6, characterized in that the legs (58) of the connecting bridge (22) are fixed by screws to the reinforcement plate (20) by passing through the cover (30).

8. Traction battery according to claim 6 or 7, characterized in that the downward vertical faces of the bridge (22) are arranged along the longitudinal direction of the vehicle.

9. Electric or hybrid motor vehicle, characterized in that it comprises a traction battery according to any one of the preceding claims which is fixed under the floor of the passenger compartment (40).

10. Motor vehicle according to claim 9, characterized in that the attachment point (24) is framed on each side by a seat support cross member fixed on top of the floor (30).

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