Traction battery vehicle floor

Abstract

Traction battery vehicle floor (20) with a plurality of self-supporting battery modules (25, 251, 252) arranged in a horizontal plane (X, Y), wherein the battery modules (25, 251, 252) are load-bearingly attached directly to two lateral longitudinal beams (21, 22) of the vehicle floor, wherein an electrical battery control module (32) with a self-supporting battery control module housing (33; 33') is arranged adjacent to the foremost and / or rearmost battery module (251, 252) in the horizontal plane (X, Y) of the battery module, and wherein the two transverse ends (37R, 37L) of the battery control module housing (33; 33') are each load-bearingly structurally connected to the corresponding longitudinal beam (21, 22), characterized in that at the two transverse ends (37R, 37L) of the Battery control module housing (33) each a transverse console (341,342;341', 342') is connected, each forming the structural connection between the respective vehicle floor longitudinal member (21,22) and the battery control module housing (33), so that the two transverse consoles (341, 342; 341', 342') close the two gaps between the centrally placed battery control housing (33) and the respective longitudinal member (21,22);

Description

The invention relates to a vehicle floor having a traction battery integrated into the vehicle floor.Because of the low center of gravity, the relatively good crash safety and the relatively good accessibility for maintenance, repair and replacement, traction batteries of battery-electric vehicles are frequently accommodated in a plate-like form in the vehicle floor. A traction battery is composed of a plurality of identical block-like battery modules, which can each have a module voltage of 20 to more than 200 V. All battery modules can be arranged in a horizontal plane and combined and accommodated in a single overall housing.Alternatively, the battery modules can be combined in a horizontal plane by a suitable frame structure and linked to the vehicle frame. EP 3 345 779 B1 discloses a crash-resistant frame structure with a rectangular closed frame, in which a plurality of battery modules and the electronic battery controller are surrounded and structurally combined in a crash-proof manner.Other structural concepts for ground-side traction batteries are known from DE 10 2015 216 225 A1, EP 3267508 B1, US 10811 645 B2, CN 20 674 989 and CN 10 3 538 457 A.DE 10 2020 117 832 A1 and DE 10 2020 112 656 A1 each disclose a traction battery vehicle floor and a self-supporting electric battery control module which is structurally connected to vehicle floor longitudinal members.It is an object of the invention to provide a traction battery vehicle floor of simple construction with good crash properties.This object is achieved according to the invention by a traction battery vehicle floor having the features of claim 1.The traction battery vehicle floor according to the invention has a multiplicity of self-supporting battery modules arranged in a single horizontal plane. The battery modules each have a crash-stable battery module housing which can be designed to be substantially fluid-tight. The module housing can be formed through which a cooling liquid can flow and in this way can be part of an active cooling circuit. Alternatively or additionally, the battery modules can also be cooled by an actively cooled cooling plate below and / or above the battery modules. In any case, the battery module housing has a rigidity and strength which protects the battery module housing against relevant deformations in the vehicle longitudinal direction and in particular in the vehicle transverse direction in the event of a vehicle crash.The battery modules are directly and load-bearingly fastened to two lateral longitudinal vehicle floor beams, which form a structural part of the self-supporting body structure. No battery module is directly attached to a cross member. In particular, no cross member is provided in the middle of the longitudinal extension of the traction battery. The required crash resistance of the traction battery in the transverse direction is produced substantially or approximately exclusively by the battery modules themselves or the battery module housings.Furthermore, a latch-shaped electric battery control module is provided, which is arranged adjacent to the frontmost and / or the rearmost battery module / s in the battery module horizontal plane. The battery control module likewise has a self-supporting and crash-stable battery control module housing which is structurally connected with its two transverse ends in each case to the corresponding longitudinal member in a supporting manner. The battery control module housing therefore contributes to the structural strengthening of the overall traction battery assembly, which consists of the battery modules, the battery control module and the two longitudinal supports.A cross console is connected to each of the two transverse ends of the battery control module housing, which cross console respectively establishes the structural connection between the respective vehicle floor longitudinal member and the battery control module housing. As a rule, the entire traction battery transverse extension is not required for accommodating the battery controller. The battery control module housing can therefore be substantially smaller in the transverse extent than the entire transverse extent of the traction battery. The resulting gaps between the respective longitudinal member and the centrally located battery control module housing are structurally closed by the two transverse brackets.Preferably, the battery modules or their housings are each formed as identical elongate cuboids, which are aligned with their longitudinal extent in the vehicle transverse direction and which are arranged in two rows extending in the vehicle longitudinal direction, each having at least three battery modules. The smallest side walls of a battery module housing are thus each located in vertical longitudinal planes, such that the entire battery module assembly has, as viewed in the vehicle longitudinal direction, a relatively large number of vertical housing side walls, which are all located in vertical transverse planes and, together with the battery control module housing, lead to a high structural transverse rigidity of the traction battery assembly.An intermediate space can be formed between the vehicle-central and mutually facing end faces of the battery modules, such that the two battery modules of a battery module gap can move towards one another in the event of a lateral vehicle crash without immediately colliding directly with one another in the process.The module housing and the two transverse brackets can be formed substantially integrally with one another, and can particularly preferably be formed together from a single die-cast aluminum part.Alternatively, the two cross brackets and the battery control module housing may be formed in multiple pieces and have been assembled together only after their manufacture. The battery control module housing may be, for example, substantially an aluminum die casting. Particularly preferably, the two transverse brackets are each formed from a chip-machined extruded profile body which can be produced economically. The two transverse brackets are preferably substantially mirror-symmetrical to one another.Preferably, the two transverse brackets each have a framework structure which provides a high structural rigidity with a low weight.Preferably, the front or rear battery control module housing vertical wall and the adjacently opposite rear or front battery module vertical wall are shaped complementarily to one another, so that when the two mentioned vertical walls meet in contact in the event of a crash, the two mentioned vertical walls lie one on the other over a large area or approximately over the full area, without particular pressure points forming in this case. In the event of a crash, a defined and uniform contact of the two mentioned vertical walls with one another therefore takes place, so that a deformation of the housings of the battery modules and of the battery control module is generally largely prevented.Particularly preferably, the two mentioned vertical walls are substantially planar. Particularly preferably, the two mutually opposing vertical walls are spaced apart from one another at a distance of at least 10 mm in the event of a non-crash, such that the vertical walls do not touch one another in the event of a slight crash.Two exemplary embodiments of the invention are explained in more detail below with reference to the drawings. The following are shown: FIG. 1 is a schematic top view of a traction battery vehicle floor including a first embodiment of a battery control module, FIG. 2 shows a vehicle-central longitudinal section II-II of the battery control module of the traction battery vehicle floor of FIG. 1 , FIG. 3 is a perspective view of the battery control module of FIG. 2 ; and FIG. 4 shows a second embodiment of a battery control module.FIG. 1 schematically shows a top view of a traction battery vehicle floor 20 with a traction battery 250 of a battery-electric passenger motor vehicle 10. The motor vehicle 10 has an electric traction motor 12 and a motor controller 14, which is supplied with electrical energy by the traction battery 250. The traction battery vehicle floor 20 is designed to lie in a horizontal plane in the manner of a plate and is arranged in the longitudinal direction X of the vehicle between a front axle and a rear axle of the motor vehicle 10.The traction battery vehicle floor 20 in the present case has two rows 23, 24 each having six identical battery modules 25, 251, 252, so that in this way six columns each having two identical battery modules 25, 251, 252 are formed. All battery modules 25, 251, 252 are arranged lying in a single horizontal plane X-Y. All battery modules 25, 251, 252 are connected electrically in series with one another in the present case. Each battery module 25, 251, 252 has a module voltage of 70 V, for example. Alternatively, however, the battery modules can also be connected electrically in parallel to one another in two electrical strings and have a module voltage of 150 V, for example.The battery modules 25, 251, 252 are each embodied in a rectangular parallelepipedal elongated fashion and are arranged with their longitudinal extent oriented in the vehicle transverse direction Y. The battery modules 25, 251, 252 are each directly fastened, for example screwed, with their distal end sides or ends of small area to a lateral longitudinal vehicle floor member 21, 22 in a supporting manner. The battery modules 25, 251, 252 each have a fluid-tight and crash-resistant battery module housing 25'. The proximal end sides or ends of the elongated battery modules 25, 251, 252 are spaced apart from one another by a few centimeters in the transverse direction Y and are mechanically connected to one another by longitudinal sheets (not illustrated). The two rearmost battery modules 251, 252 which form a rearmost battery module column are adjoined in the same horizontal plane X, Y by a battery control latch 30 having a vehicle-central battery control module 32; 32', which encloses a battery control electronics 35 for monitoring and controlling the battery modules 25, 251, 252 in a self-supporting and crash-stable battery control module housing 33; 33'.In the first embodiment shown in FIGS. 1-3, the battery control module housing 33 is a separate aluminum die casting formed from a tray and a threaded lid. Adjoining the two transverse ends 37R, 37L of the housing 33 is a respective transverse bracket 341, 342, which has a framework structure. The two transverse brackets 341, 342 are each formed from a chip-machined extruded profile body 34.Each transverse bracket 341, 342 is connected in each case by its one transverse end in a structurally fixed manner to the battery control module housing 33 and by its other transverse end in each case to the relevant vehicle floor longitudinal member 21, 22, for example screwed, or alternatively welded, by means of screw bolts 401, 402. In this way, the battery control latch 30 forms a transverse reinforcement of the traction battery vehicle floor 20, so that in this region additional reinforcement on the vehicle body side in the transverse direction is largely unnecessary.As can be seen in FIG. 2, the front vertical wall 39 of the battery control module housing 33 and the adjacently opposite rear battery module vertical wall 29 of the adjoining battery module 251, 252 are each completely planar and are spaced apart from one another by a distance A of approximately 15 mm. In the case of a severe rear crash event, therefore, a smaller deformation of the battery control latch 30 does not cause a deformation of the adjacent battery modules 251, 252. Even in the case of a strong deformation of the battery control latch 30, no force is applied at points into the battery module vertical wall 29 because of the smoothness of the two mutually opposite vertical walls 29, 39.As indicated in FIG. 2, an actively liquid-cooled cooling plate 21 is arranged on the underside of the battery modules 25, 251, 252 and of the battery control module 32.In FIG. 4, a second exemplary embodiment of the battery control latch 30' is shown, wherein here the battery control module housing 33' and the two transverse brackets 341', 342' are formed substantially integrally with one another and are formed by aluminum die-cast parts 33', 34' which are connected integrally with one another.

Claims

Traction battery vehicle floor (20) having a multiplicity of self-supporting battery modules (25, 251, 252) arranged in a horizontal plane (X, Y), wherein the battery modules (25, 251, 252) are directly fastened supportingly to two lateral vehicle floor longitudinal members (21, 22), wherein an electric battery control module (32) having a self-supporting battery control module housing (33; 33') is arranged adjacent to the foremost and / or rearmost battery module (251, 252) in the battery module horizontal plane (X, Y), and wherein the two transverse ends (37R, 37L) of the battery control module housing (33; 33') are each structurally connected supportingly to the corresponding longitudinal member (21, 22), characterized in that, that a transverse bracket (341, 342; 341', 342') is connected to each of the two transverse ends (37R, 37L) of the battery control module housing (33), said transverse bracket forming the structural connection between the relevant vehicle floor longitudinal member (21, 22) and the battery control module housing (33), so that the two transverse brackets (341, 342; 341', 342') close the two gaps between the centrally located battery control housing (33) and the respective longitudinal member (21, 22)The traction battery vehicle floor (20) of claim 1, wherein the two cross brackets (341,342;341',342') comprise a truss structure.The traction battery vehicle floor (20) according to claim 1 or 2, wherein the battery control module housing (33') and the two cross brackets (341', 342') are formed substantially integrally with each other, and more preferably, are formed from a single aluminum die casting.Traction battery vehicle floor (20) according to Claim 1 or 2, wherein the battery control module housing (33) and the two transverse brackets (341, 342) are formed in multiple pieces, wherein the transverse brackets (341, 342) particularly preferably each consist of a chip-machined extruded profile body (34).The traction battery vehicle floor (20) of any preceding claim, wherein the front or rear battery control module housing vertical wall (39) and the adjacently opposing rear or front battery module vertical wall (29) are shaped complementary to each other.Traction battery vehicle floor (20) according to Claim 5, wherein the two mutually opposite vertical walls (39, 29) are spaced apart from one another in the non-crash case by a distance (A) of at least 10 mm.Traction battery vehicle floor (20) according to one of the preceding claims, wherein the battery modules (25, 251, 252) are of elongate design, are aligned with their longitudinal extent in the vehicle transverse direction (Y) and are arranged in two rows (23, 24), which extend in the vehicle longitudinal direction (X), each having at least three battery modules (25, 251, 252).

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