DE102020106780A1 - Battery with module holder for receiving hot gas and motor vehicle - Google Patents

Abstract

The invention relates to a battery (1) for a motor vehicle, having at least one battery module (2) with a cell pack (4) composed of a plurality of battery cells (5) stacked one on top of the other along a stacking direction (S) and with a cell module frame (9) for Holding the cell pack (4), the battery cells (5) having degassing elements (7) arranged on at least one side area (6) of the cell pack (4) for discharging a hot gas (8), a battery housing for accommodating the at least one battery module (2) ); and- at least one module holder (11) extending in the stacking direction (S), which is fastened to the battery housing, to which the cell module frame (9) is fastened and which has at least one receiving chamber (16) for hot gas extending along the stacking direction (S) (8), wherein a wall area (17) of the receiving chamber (16) faces the side area (6) of the cell pack (4) with the degassing elements (7) and is designed to discharge the hot gas (8) of at least one battery cell (5) to let into the receiving chamber (16).

Description

The invention relates to a battery for a motor vehicle having at least one battery module with a cell pack composed of a plurality of battery cells stacked one on top of the other along a stacking direction and with a cell module frame for holding the cell pack. The invention also relates to a motor vehicle.

In the present case, the interest is directed towards batteries for motor vehicles, in particular traction batteries for electrically driven motor vehicles, that is to say hybrid or electric vehicles. Such batteries usually have a plurality of battery modules which are interconnected with one another and are arranged in a battery housing. The battery modules have an interconnection made up of a plurality of battery cells, which are stacked, for example, along a stacking direction to form a cell pack. The battery cells usually have a degassing element, for example a bursting membrane, via which a hot gas that occurs in a cell housing of the battery cell in the event of a thermal event can escape from the cell housing.

This hot gas transports heat and hot particles from the cell housing of the battery cell into an interior of the battery housing. The particles can cause short circuits in other parts of the battery module or the battery. These electrical short circuits near or far from the degassing battery cell can result in further thermal events, i.e. thermal propagation. For example, from the DE 10 2018 206 793 A1 a cover for a battery housing of a motor vehicle high-voltage battery is known, which has a perforated plate with a plurality of passage openings. The perforated plate is covered by a film that seals the passage openings. The film is designed in such a way that it is at least partially destroyed at a predetermined temperature acting on the film, thereby exposing the passage openings. However, the perforated plate with the film is an additional component which undesirably increases the cost and weight of the battery.

It is the object of the present invention to provide a cost-effective and weight-saving solution for taking up hot gas from a battery cell of a battery of a motor vehicle.

According to the invention, this object is achieved by a battery and a motor vehicle having the features according to the respective independent claims. Advantageous embodiments of the invention are the subject matter of the dependent claims, the description and the figures.

A battery according to the invention for a motor vehicle has at least one battery module. The at least one battery module has a cell pack made up of a plurality of battery cells stacked one on top of the other along a stacking direction and a cell module frame for holding the cell pack, the battery cells having degassing elements arranged on at least one side area of the cell pack for discharging a hot gas. In addition, the battery has a battery housing for receiving the at least one battery module and at least one module holder extending in the stacking direction, which is fastened to the battery housing, to which the cell module frame for holding the at least one battery module is fastened and which at least one extending along the stacking direction Has receiving chamber for hot gas. When the at least one battery module is attached to the at least one module holder, a wall area of the receiving chamber faces the side area of the cell pack with the degassing elements and is designed to let the hot gas of at least one battery cell of the cell pack into the receiving chamber.

The battery is designed in particular as a traction battery for an electrically drivable motor vehicle. In particular, the battery is designed as a high-voltage battery or a high-voltage accumulator. The battery cells are designed in particular as prismatic battery cells with a flat, cuboid cell housing and are stacked in the stacking direction to form the cell pack or cell stack. The cell housings have a housing base, a housing cover, a housing front wall, a housing rear wall and two housing side walls. The housing covers form an upper side of the cell stack, the housing bottoms form an underside of the cell stack and the housing side walls form the side areas of the cell stack. The housing front wall of a battery cell arranged on the front side in the cell packet forms a front side of the cell packet and the rear housing wall of a battery cell arranged on the rear side in the cell packet forms a rear side of the cell packet. The battery cells have degassing elements, for example bursting membranes, which are arranged here in particular on at least one of the housing side walls. The degassing elements are used to discharge a hot gas from the cell housing in the event of a thermal event in a battery cell. The degassing elements are thus arranged on at least one side area of the cell stack. It can also be that a degassing element is arranged on each housing side wall of a battery cell or that the degassing elements of the battery cells are arranged alternately on a first and a second housing side wall in the cell stack, so that degassing elements are arranged on both side areas of the cell stack.

The battery also has the battery housing, which can be formed from aluminum, for example. The battery housing has, for example, a trough-like lower housing part and an upper housing part or a housing cover, which enclose an interior space for receiving the at least one battery module. The lower housing part can, for example, have a base area and a wall surrounding the base area. To hold the at least one battery module, the at least one module holder is fastened to the battery housing, in particular to the housing lower part. The module holder is in particular strut-like, for example designed as a cross strut, which extends in a transverse direction (parallel to the stacking direction) between two areas of the wall of the lower housing part that are opposite one another in the transverse direction. For example, the at least one module holder can be welded to the battery housing.

The at least one battery module is fastened to at least one module holder. The module holder can also hold several battery modules arranged one behind the other in the stacking direction. In particular, the at least one battery module is fastened to two module holders which are arranged parallel and spaced apart from one another and which extend along the stacking direction along the two opposite side regions of the cell package. A plurality of battery modules can be arranged next to one another perpendicular to the stacking direction or transverse direction, in a longitudinal direction, wherein two adjacent battery modules can share the module holder located in between. In addition to holding the at least one battery module, the module holder is preferably designed to receive an accident-related application of force to the battery.

In addition, the at least one module holder functions as a hot gas sensor in the event that a battery cell is degassed. For this purpose, the at least one module holder extends along the side area of the cell stack with the degassing elements. The degassing elements therefore face the at least one module holder, so that the at least one module holder lies in a flow path of a hot gas emerging from the battery cells. The at least one module holder has the at least one receiving chamber, which extends along the side area with the degassing elements, to receive the hot gas, in particular hot particles, which are transported out of the cell housings by the hot gas. The receiving chamber has the wall area which is arranged so as to overlap with the side area with the degassing elements. The hot gas with the hot particles of a battery cell can penetrate into the receiving chamber via this wall area and be collected there and / or discharged from there.

By introducing the hot gas into the receiving chamber, it can be achieved that the particles are specifically collected at a point at which they cannot cause any damage, for example an undesired short circuit, in the battery. By using the module holder for receiving the hot gas, which is required anyway, it is also advantageously possible to dispense with space-consuming and expensive additional components.

It can be provided that the at least one module holder is designed as a tube which has a cavity extending in the stacking direction as the receiving chamber. The tube can have any cross-section, for example a rectangular or trapezoidal cross-section. A pipe wall facing the side area of the cell stack and adjoining the cavity forms the wall area via which the hot gas can penetrate into the receiving chamber. Such a module holder designed as a tube is particularly easy to manufacture.

The at least one module holder is particularly preferably designed as a double tube, which has two receiving chambers in the form of cavities extending in the stacking direction, an intermediate wall between the receiving chambers being designed as a double-T-beam extending in the stacking direction, which is designed to to absorb an accident-related application of force to the battery housing. Such a module holder can be designed, for example, as an extruded extruded profile. The module holder is used in particular to hold at least two battery modules, the module holder being arranged between the at least two battery modules. A receiving chamber is assigned to each battery module, a first receiving chamber being arranged adjacent to a first side of the double T-beam and a second receiving chamber being arranged adjacent to a second side of the double T-beam. A first lateral tube wall facing the side area of a first battery module forms a first wall area of the first receiving chamber and a second lateral tube wall facing the side area of a second battery module forms a second wall area of the second receiving chamber. Because the double T-beam serves as a crash element, which is designed to absorb a force on the battery as a result of an accident in the motor vehicle and thus to prevent destruction of the battery cells, the pipe walls can be particularly thin be formed so that the module holder is designed to be particularly weight-saving.

It proves to be advantageous if the at least one wall area has a perforation for admitting the hot gas into the receiving chamber. The wall area can therefore have a multiplicity of openings through which the hot gas and the particles can penetrate into the receiving chamber. The at least one wall area can also have at least one predetermined breaking point, which can be destroyed when the hot gas is applied in order to let the hot gas into the receiving chamber. For example, the predetermined breaking point can be produced by designing the wall area with such a small thickness that it can be melted at least in certain areas by the hot gas impinging on it.

In one embodiment of the invention, the module frame has at least one wing-like holding element protruding from the side area of the cell packet, which is placed on an upper side of the module holder and is fastened to the module holder. In particular, the battery has a terminal strip which is arranged on the at least one wing-like holding element and is mechanically connected to the top of the module holder, so that the at least one wing-like holding element is clamped between the upper side of the module holder and the terminal strip. The battery module can therefore be attached to the module holder while hanging. The upper side can be formed, for example, by a horizontally extending flange of the double T-beam. The top can have screw holes into which screws of the terminal strip can be screwed.

In an advantageous development of the invention, the battery housing has a wall profile with a hollow channel, the at least one module holder being connected to the wall profile in such a way that the receiving chamber opens into the hollow channel and that the hot gas located in the receiving chamber comes from an interior space via the hollow channel of the battery housing can be derived. The wall profile can be formed, for example, by the walls of the lower housing part which extend in the longitudinal direction and to which the module holders, which are designed as transverse struts, are attached. The wall profile thus forms side sills of the battery housing that extend in the longitudinal direction. Openings can be arranged in the wall profile, which are arranged in alignment with openings in the receiving chambers of the module holder. The hollow channel is arranged in particular outside the battery housing. The hot gas introduced into the receiving chamber can thus be diverted to the outside from the interior of the battery housing via the hollow channel of the wall profile. This can prevent further components in the interior of the battery housing from overheating due to the hot gas of a battery cell.

The invention also relates to a motor vehicle with a battery according to the invention. The motor vehicle is designed in particular as an electrically drivable motor vehicle.

The embodiments presented with reference to the battery according to the invention and their advantages apply accordingly to the motor vehicle according to the invention.

Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respectively specified combination, but also in other combinations or on their own.

• 1 eine Explosionsdarstellung von Teilen einer Batterie;
• 2 eine schematische Darstellung eine Modulhalterung und ein Zellpaket der Batterie;
• 3 eine schematische Darstellung einer ersten Ausführungsform der Modulhalterung;
• 4 eine schematische Darstellung einer zweiten Ausführungsform der Modulhalterung; und
• 5 eine schematische Darstellung einer dritten Ausführungsform der Modulhalterung.

The invention will now be explained in more detail using a preferred exemplary embodiment and with reference to the drawings. Show it:

• 1 an exploded view of parts of a battery;
• 2 a schematic representation of a module holder and a cell pack of the battery;
• 3 a schematic representation of a first embodiment of the module holder;
• 4th a schematic representation of a second embodiment of the module holder; and
• 5 a schematic representation of a third embodiment of the module holder.

Identical and functionally identical elements are provided with the same reference symbols in the figures.

1 shows part of a battery 1 for a motor vehicle in an exploded view. The battery 1 has a large number of battery modules here 2 on which in a battery case the battery 1 to be ordered. Only a lower housing part of the battery housing is here 3 shown. The battery modules 2 each have a cell package 4th of prismatic battery cells stacked one behind the other in the stacking direction S 5 on. The cell package 4th is in a highly simplified representation in 2 shown. The cell package 4th has two opposite side areas 6th which extend along the stacking direction S and on which degassing elements 7th of the battery cells 5 are arranged. Through the degassing elements 7th can a faulty hot gas 8th a battery cell 5 from a cell housing of the battery cell 5 escape. The cell package 4th is in a cell module frame 9 arranged, which in 1 is shown and which is designed to the cell package 4th to brace. Via the cell module frame 9 can the battery module 2 can be fixed in the battery case. The cell module frame 9 has wing-like retaining elements 10 on which of the side areas 6th of the cell package 4th stick out.

Also, the battery has 1 Module brackets 11 on, which here as extending in the transverse direction Q over the lower housing part 3 extending cross struts are formed. The module brackets 11 are arranged at a distance from one another along a longitudinal direction L, so that between two module brackets 11 at least one battery module 2 , can be arranged. Here are two battery modules 2 in the transverse direction Q one behind the other between two module brackets 11 arranged. Two adjacent battery modules in the longitudinal direction L. 2 share an intermediate module bracket here 11 . The module brackets 11 are on the lower part of the housing 3 attached, for example welded. The module brackets 11 have a top 12th on which screw holes here 13th having. On the tops 12th two adjacent module brackets 11 are the wing-like retaining elements 10 a battery module 2 placed so that a battery module 2 of two module brackets 11 which is held along the side areas 6th and thus extend parallel to the stacking direction S. The battery module 2 is therefore in the area of the holding elements 10 on the module brackets 11 on. A terminal block 14th with screws 15th is on the retaining elements 10 hung up, and with the top 12th a module bracket 11 connected by the screws 15th in the screw holes 13th be screwed in. The holding elements 10 so be between the tops 12th of the module brackets 11 and the terminal strips 14th clamped, making the battery module 1 is held on both sides.

The module brackets 11 also serve to control the hot gas 8th a degassing battery cell 5 to record. The module bracket 11 , as in 2 shown, at least one receiving chamber 16 on which the hot gas 8th as well as by the hot gas 8th transported particles can be introduced. A wall area 17th the receiving chamber 16 extends along the side area 6th of the cell package 4th with the degassing elements 7th and is thus overlapping with the side area 6th arranged. About the wall area 17th can the hot gas 8th into the receiving chamber 16 are introduced and collected there or also derived. For example, as in 1 shown, a wall profile 18th of the battery housing a hollow channel 19th have, which is arranged outside of the battery housing. The receiving chambers 16 of the module brackets 11 can be attached to the hollow channel 19th be connected so that the hot gas 8th from the receiving chambers 16 into the hollow channel 19th and from there to an area around the battery 1 can be derived.

In 3 , 4th and 5 are different embodiments of a module holder 11 shown. For example, the module holder 11 , as in 3 and 4th shown, be designed as a double pipe with a double T-beam 20. The double-T-beam 20 forms an intermediate wall between two receiving chambers 16 . The double T-beam 20 is also used to accommodate an accident force on the battery 1 . The module bracket 11 according to 5 is as a tube with only one receiving chamber 16 educated. Here, however, are the wall areas 17th formed with a greater thickness, so that the module bracket 11 according to 5 can also accommodate an accident worker. With the module holder 11 according to 3 are the wall areas 17th the reception chambers 16 made so thin that they are affected by the impinging hot gas 8th are locally melted and the hot gas 8th into the respective receiving chamber 16 can penetrate. With the module brackets 11 according to 4th and 5 indicate the wall areas 17th a perforation 21 on over which the hot gas 8th into the respective receiving chamber 16 can penetrate.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102018206793 A1 [0003]

Claims (10)

Having a battery (1) for a motor vehicle - At least one battery module (2) with a cell pack (4) composed of a plurality of battery cells (5) stacked one on top of the other along a stacking direction (S) and with a cell module frame (9) for holding the cell pack (4), the battery cells (5) have degassing elements (7) arranged on at least one side area (6) of the cell stack (4) for discharging a hot gas (8), - A battery housing for accommodating the at least one battery module (2); and - At least one module holder (11) extending in the stacking direction (S), which is attached to the battery housing, to which the cell module frame (9) for holding the at least one battery module (2) is attached and which at least one extends along the stacking direction (S ) has extending receiving chamber (16) for hot gas (8), wherein in the attached state of the at least one battery module (2) on the at least one module holder (11) a wall area (17) of the receiving chamber (16) the side area (6) of the cell pack ( 4) facing with the degassing elements (7) and is designed to let the hot gas (8) of at least one battery cell (5) of the cell pack (4) into the receiving chamber (16). Battery (1) Claim 1 , characterized in that the at least one battery module (2) is attached to two parallel and spaced apart module holders (11) which extend along the stacking direction (S) along the two opposite side areas (6) of the cell pack (4). Battery (1) according to one of the preceding claims, characterized in that the at least one module holder (11) is designed as a tube which has a cavity extending in the stacking direction (S) as the receiving chamber (16). Battery (1) according to one of the preceding claims, characterized in that the at least one module holder (11) is designed as a double tube which has two receiving chambers (16) in the form of cavities extending in the stacking direction (S), with a partition between the receiving chambers (16) is designed as a double-T-beam (20) which extends in the stacking direction (S) and is designed to receive an accident-related application of force to the battery (1). Battery (1) according to one of the preceding claims, characterized in that the at least one wall area (17) has a perforation (21) for admitting the hot gas (8) into the receiving chamber (16). Battery (1) according to one of the preceding claims, characterized in that the at least one wall area (17) has at least one predetermined breaking point which, when exposed to the hot gas (8), allows the hot gas (8) to be admitted into the at least one receiving chamber (16). is destructible. Battery (1) according to one of the preceding claims, characterized in that the module frame (9) has at least one wing-like holding element (10) protruding from the side area (6) of the cell packet (4) and which is attached to an upper side (12) of the module holder (11) is placed and is attached to the module holder (11). Battery (1) Claim 7 , characterized in that the battery (1) has a terminal strip (14) which is arranged on the at least one wing-like holding element (10) and is mechanically connected to the top (12) of the module holder (11) so that the at least one wing-like Holding element (10) is clamped between the top (12) of the module holder (11) and the terminal strip (14). Battery (1) according to one of the preceding claims, characterized in that the battery housing has a wall profile (18) with a hollow channel (19), wherein the at least one module holder (11) is connected to the wall profile (18) in such a way that the at least a receiving chamber (16) opens into the hollow channel (19) and that the hot gas (8) located in the receiving chamber (16) can be discharged from an interior of the battery housing via the hollow channel (19). Motor vehicle with a battery (1) according to one of the preceding claims.

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