Traction battery system for a motor vehicle

Abstract

The invention relates to a traction battery system (1) of a motor vehicle, comprising at least two battery modules (2), each battery module comprising a plurality of batteries, the battery module (2) comprising a module housing (3) comprising a housing container (11) and at least one housing cover (7), the battery module (2) comprising a gas venting unit (9) having a gas venting opening (10) and having a bursting element (12), via which gas is discharged from the module housing, the traction battery system comprising a first longitudinal support (4) and a second longitudinal support (5), the battery modules (2) being arranged between the first and the second longitudinal support, the longitudinal supports having a gas venting chamber (13) configured to receive and to conduct the gas flowing via the gas venting unit (9). A cooling chamber (14) extending along the gas venting chamber (13) is arranged separately from the gas venting chamber for cooling the gas flowing in the longitudinal supports (4; 5).

Description

Technical Field

[0001] This invention relates to a traction battery system for motor vehicles. Background Technology

[0002] Motor vehicles incorporating traction battery systems are well-known. A traction battery system comprises multiple battery modules consisting of multiple battery cells configured for electrically driving the motor vehicle. The multiple battery cells are bundled together to form a battery module, which is then housed within the battery casing of the traction battery. The traction battery system is housed within a receiving space of the main body of the motor vehicle.

[0003] During operation of the traction battery system, such as due to a so-called thermal event, degassing of the battery cells may occur, and the resulting gas is discharged from the traction battery system in a controlled manner. To discharge the gas, a venting unit is provided, which includes a bursting element that can yield when the internal pressure in the battery module increases due to the gas, and can open a venting opening associated with the venting unit, allowing the gas to escape from the battery module.

[0004] Patent application DE 10 2018 210 307 A1 discloses an electric vehicle with a traction battery system comprising a plurality of battery cells, each battery cell having a housing and an exhaust unit, wherein the traction battery system is fastened to the body of the electric vehicle by a support structure, and wherein the support structure includes a cavity fluidly connected to the exhaust unit, such that fluid exiting the housing via the exhaust unit can be discharged via the cavity of the support structure.

[0005] Patent application WO 2021 / 053133 A1 discloses a traction battery system for a motor vehicle, comprising a housing, a plurality of battery cells disposed within the housing, and a substrate, wherein the battery cells are disposed on the substrate. The substrate includes cavities, wherein the cavities are fluidly connected to the housing via venting openings.

[0006] A motor vehicle having a traction battery system is known from patent application CN 112531246 A, wherein the traction battery system is configured with a frame for securing the traction battery system to the body of the motor vehicle and a plurality of battery modules secured to the frame, wherein the frame includes cavities that are fluidly connected to the battery modules via corresponding openings and for venting gases generated during thermal events.

[0007] Patent application DE 10 2011 100 626 A1 discloses a traction battery system for a motor vehicle, wherein the traction battery system includes an exhaust opening that is fluidly connected to a cavity of a support member of a support structure of the motor vehicle.

[0008] A traction battery system for a motor vehicle is known from patent applications DE 10 2019 100 955 A1 and DE 10 2017 117 354 A1, wherein the traction battery system includes a plurality of battery cells, each battery cell including an exhaust element, wherein the exhaust element is fluidly connected to an exhaust manifold. Summary of the Invention

[0009] The purpose of this invention is to provide an improved traction battery system for motor vehicles.

[0010] According to the invention, this objective is achieved by a motor vehicle comprising a traction battery system including the features described below. Advantageous embodiments with useful and important further developments of the invention are described accordingly below.

[0011] The traction battery system for a motor vehicle according to the present invention includes at least two battery modules, each battery module including a plurality of batteries, wherein the battery module has a module housing, the module housing including a housing container and at least one housing cover. The battery module includes an exhaust unit having an exhaust opening and a bursting element, wherein gas can be discharged from the module housing via the exhaust opening. The traction battery system includes a first longitudinal support and a second longitudinal support, the battery module being disposed between the first longitudinal support and the second longitudinal support. The longitudinal support includes an exhaust chamber configured to receive and convey gas flowing through the exhaust unit. According to the present invention, a cooling chamber extending along the exhaust chamber is separately configured from the exhaust chamber for cooling gas flowing in the longitudinal support. An advantage of the present invention is the reduction of the temperature of the hot gas flowing in the exhaust chamber, thus significantly reducing, for example, damage to another battery module or at least one other battery module due to hot gas.

[0012] By means of an exhaust chamber configured in the longitudinal support and typically extending in the direction of the longitudinal axis of the vehicle body, gases generated, for example, during thermal events such as degassing of one or more batteries, can be released in a controlled manner. The gases are discharged from the system in such a way that they are cooled during discharge, preventing further, particularly sensitive components such as other intact batteries, from being damaged by the hot gases. The cooling of the discharged gases results in a significant temperature reduction, so components adjacent to the longitudinal support are not heated, for example, by heat transfer, or are heated to a lesser extent.

[0013] The separate construction of the cooling chamber and the exhaust chamber results in preferred cooling because a cooling medium that is not guided to the outside and thus discharged along with the gas in the exhaust chamber can be used. Simple air cooling can also be achieved because air flows through the cooling chamber.

[0014] Cooling also reduces the reactivity of the gas with oxygen in the fresh air, thereby further limiting damage.

[0015] Implementing an exhaust chamber in the longitudinal support has the further advantage of preventing flame formation because the gas flowing out of the module housing can flow along the longest possible path in a channel of limited size, thus allowing for additional cooling before it can react with the large amount of oxygen in the surrounding air.

[0016] The longitudinal support advantageously includes a cooling chamber. Therefore, a cooling chamber can be easily configured adjacent to the exhaust chamber. Due to wall heat transfer, the cooling chamber adjacent to the exhaust chamber results in particularly effective cooling.

[0017] The longitudinal support is advantageously and cost-effectively produced using extrusion molding or in an extrusion process. Therefore, different chamber profiles can be easily achieved, whereby the chamber can be realized according to the extension of the longitudinal support and then extends through the longitudinal support.

[0018] In a further advantageous configuration, in addition to the exhaust chamber, the exhaust unit includes an auxiliary channel disposed between the exhaust opening and the exhaust chamber. For example, if the exhaust chamber, or in other words, the longitudinal support, is not implemented at the same height as the exhaust opening, the auxiliary channel can therefore serve as a deflection channel. Even in complex designs, the auxiliary channel can provide a reliable exhaust unit. The auxiliary channel is advantageously disposed within the housing cover or in a tubular element configured adjacent to the housing cover.

[0019] In another configuration, a sealing element is positioned between the auxiliary passage and the exhaust chamber to prevent overflow from the auxiliary passage through the exhaust passage.

[0020] The valve is advantageously positioned in the auxiliary channel. This prevents gas from the exhaust chamber from entering the module housing. This is particularly advantageous because during degassing, the entry of fresh oxygen-containing air into the module housing through the exhaust opening caused by the destruction or opening of the rupture element can lead to a significant increase in the rate of the chemical reaction between the gas and the oxygen in the fresh air.

[0021] In another configuration of the traction battery system according to the invention, battery modules are arranged in series between longitudinal supports transverse to the direction of travel of the motor vehicle, wherein in each case only one battery module is housed between the longitudinal supports in the direction of the longitudinal axis of the traction battery system. In other words, in each case only one module housing is housed between the longitudinal supports in the direction of travel or when viewed along the longitudinal axis, wherein multiple module housings are arranged one after another between the longitudinal supports. This allows for improved stability of the traction battery system.

[0022] The longitudinal support is preferably located in the area of ​​the foot pedal of the main body of the motor vehicle.

[0023] In another configuration, the housing is produced at low cost in the form of a hollow profile during extrusion and can be closed by means of a housing cover on at least one of its open ends. In this way, a cost-effective modular housing that at least partially includes an exhaust unit can be provided.

[0024] Connecting elements can also be located in the exhaust chamber, for example, for securing the substrate covering the traction battery system.

[0025] The exhaust chamber is advantageously completely closed at the end configured to face the front of the vehicle body, so that the gas flowing in the exhaust chamber is guided toward the rear of the vehicle body.

[0026] If the rupture element has a higher pressure resistance relative to the pressure applied to the side of the rupture element configured away from the module housing than to the pressure applied to the side of the rupture element configured to face the module housing, it is advantageous to prevent gas from flowing into the module housing via the exhaust chamber.

[0027] Therefore, a traction battery system for motor vehicles is provided, which optimizes the use of installation space in the motor vehicle for maximum customer benefit. Overall, the traction battery system features a simple and therefore cost-effective design, and can reduce the rate of thermal events.

[0028] In general, the present invention provides the following technical solution 1, and the following 2-14 are preferred technical solutions:

[0029] 1. A traction battery system (1) for a motor vehicle, comprising at least two battery modules.

[0030] (2) Each battery module includes multiple batteries, wherein the battery module (2) includes a module housing (3), the module housing includes a housing container (11) and at least one housing cover (7), and wherein the battery module (2) includes an exhaust unit (9) having an exhaust opening (10) and an explosion element (12), wherein gas can be discharged from the module housing (3) through the exhaust opening (10), and wherein the traction battery system (1) includes a first longitudinal support (4) and a second longitudinal support (5), the battery module (2) is disposed between the first longitudinal support and the second longitudinal support, and wherein the longitudinal support (4; 5) has an exhaust chamber (13) configured to receive and convey gas flowing through the exhaust unit (9).

[0031] Its features are,

[0032] A cooling chamber (14) extending along the exhaust chamber (13) is configured separately from the exhaust chamber for cooling the gas flowing in the longitudinal support (4; 5).

[0033] 2. The traction battery system (1) described in 1 above,

[0034] Its features are,

[0035] The longitudinal support members (4; 5) include the cooling chamber (14).

[0036] 3. The traction battery system (1) according to 1 or 2 above,

[0037] Its features are,

[0038] The cooling chamber (14) is configured to be adjacent to the exhaust chamber (13).

[0039] 4. The traction battery system (1) according to any one of 1 to 3 above,

[0040] Its features are,

[0041] The cooling chamber (14) includes a cooling medium.

[0042] 5. The traction battery system (1) according to any one of 1-4 above,

[0043] Its features are,

[0044] The longitudinal support members (4; 5) are produced using an extrusion molding method or in an extrusion process.

[0045] 6. The traction battery system (1) according to any one of 1-5 above,

[0046] Its features are,

[0047] In addition to the exhaust chamber (13), the exhaust unit (9) also includes an auxiliary channel (15) disposed between the exhaust opening (10) and the exhaust chamber (13).

[0048] 7. The traction battery system (1) described in 6 above,

[0049] Its features are,

[0050] The auxiliary channel (15) is disposed in the housing cover (7) or in a tube element (19) disposed adjacent to the housing cover (7).

[0051] 8. The traction battery system (1) according to any one of 6 or 7 above,

[0052] Its features are,

[0053] A sealing element (18) is disposed between the auxiliary channel (15) and the exhaust chamber (13).

[0054] 9. The traction battery system (1) according to any one of 6 to 8 above,

[0055] Its features are,

[0056] The valve is located in the auxiliary channel (15).

[0057] 10. The traction battery system (1) according to any one of 1-9 above,

[0058] Its features are,

[0059] The battery modules (2) are arranged in series between the longitudinal supports (4, 5) transversely to the direction of travel (F) of the motor vehicle, wherein in each case only one battery module (2) is arranged in series between the longitudinal supports (4, 5) along the longitudinal axis (23) of the traction battery system (1).

[0060] 11. The traction battery system (1) according to any one of the preceding 1-10,

[0061] Its features are,

[0062] The shell container (11) is produced in the form of a hollow profile in an extrusion process and can be closed on at least one of the open ends of the shell container by means of the shell cover (7).

[0063] 12. The traction battery system (1) according to any one of 1-11 above,

[0064] Its features are,

[0065] The connecting element (24) is disposed in the exhaust chamber (13).

[0066] 13. The traction battery system (1) according to any one of 1-12 above,

[0067] Its features are,

[0068] The exhaust chamber (13) is completely closed at its end, which is configured to face the front of the main body of the motor vehicle.

[0069] 14. The traction battery system (1) according to any one of 1-13 above,

[0070] Its features are,

[0071] The blasting element (12) has higher pressure resistance relative to the pressure applied to the side of the blasting element (12) configured to face away from the module housing (3) than to the pressure applied to the side of the blasting element (12) configured to face the module housing (3). Attached Figure Description

[0072] Other advantages, features, and details of the invention will become apparent from the following description and drawings of preferred design examples. The features and combinations of features mentioned above in the specification, as well as the features and combinations of features mentioned below in the description of the drawings and / or shown separately in the drawings, can be used not only in the combinations specifically indicated, but also in other combinations or individually without departing from the scope of the invention. The drawings show:

[0073] Figure 1 A perspective view shows a traction battery system according to the invention in a first exemplary embodiment.

[0074] Figure 2 Section II-II, which runs along the plane of the YZ main axis, shows the... Figure 1 The traction battery system,

[0075] Figure 3 A traction battery system according to the invention in a second exemplary embodiment is shown in cross-section, and

[0076] Figure 4 Section IV-IV, along the plane of the YZ main axis, shows the... Figure 3 Traction battery system. Detailed Implementation

[0077] The traction battery system 1 of the present invention for electric motor vehicles, not shown in detail, is as follows: Figure 1 The configuration is shown in the diagram. In this exemplary embodiment, the traction battery system 1 has six battery modules 2, each battery module including a module housing 3 that houses multiple battery cells. It goes without saying that the number of battery modules 2 can be selected as needed, particularly taking into account the power output and installation space of the motor vehicle. The traction battery system 1 is fastened to a first longitudinal support 4 and a second longitudinal support 5, wherein the battery modules 2 are preferably oriented transversely to the direction of travel F of the motor vehicle. In other words, the battery modules 2 are housed in series transversely to the direction of travel F between the longitudinal supports 4 and 5, wherein in each case, viewed in series, only one battery module 2 is disposed between the longitudinal supports 4 and 5.

[0078] The two longitudinal supports 4 and 5 are configured as mounting supports, making it easier to install the traction battery system 1 onto the vehicle body (not shown in more detail). This is because the use of the two longitudinal supports 4 and 5, which are fastened to the vehicle body before connecting the traction battery system 1, forms a vehicle module 6 on the traction battery system 1, which can be easily connected to the main body in a simple manner. For example, the longitudinal supports 4 and 5 can be fastened to the vehicle body's foot pedals.

[0079] Facing the two longitudinal supports 4 and 5, each individual module housing 3 includes a housing cover 7, which is held on the housing container 11 of the module housing 3, for example by means of a latching connection 8, and is preferably produced in the form of a hollow profile in an extrusion molding or extrusion process.

[0080] To release gases that may occur during the operation of the traction battery system 1 when the battery cells degas, for example due to a so-called thermal event, the battery module 2 includes a venting unit 9 with a venting opening 10, wherein the venting opening 10 is advantageously disposed within the housing cover 7, as shown below. Figure 2 As shown in the diagram. Both housing covers 7 associated with the module housing 3 may include vent openings 10; alternatively, only one of the two housing covers 7 may include vent openings 10. Vent openings 10 may also be configured within the housing container 11 of the module housing 3.

[0081] An elastic bursting element 12, in the form of a disc and capable of rupturing above a specific pressure, is housed in the exhaust opening 10. The bursting element 12 can advantageously be configured as a membrane that ruptures under the dominant specific pressure within the module housing 3. This means that if a pressure exists within the module housing 3 that corresponds to or exceeds the specific pressure, the exhaust opening 10 is opened due to the rupture or, in other words, tearing of the bursting element 12, and gas escapes from the module housing 3.

[0082] For controlled gas emission, the exhaust unit 9 includes an exhaust chamber 13 in which gas flowing in via the exhaust opening 10 can be conveyed, preferably reaching the environment. In this design example, the exhaust chamber 13 is disposed within longitudinal supports 4 and 5. In other words, the exhaust opening 10 is connected to the exhaust chamber 13 for flow, allowing gas to flow from the exhaust opening 10 into the exhaust chamber 13 for conveyance therefrom.

[0083] The longitudinal supports 4 and 5 are configured in the form of longitudinal profiles and include at least one additional chamber, namely a cooling chamber 14, wherein chambers 13 and 14 extend in the direction of the longitudinal axis 23 of the traction battery system 1, which also corresponds to the longitudinal axis of the longitudinal supports 4 and 5. The longitudinal supports 4 and 5 are produced in an extrusion molding or extrusion process, wherein the cooling chamber 14 is configured to be directly adjacent to the exhaust chamber 13. The cooling chamber 14 is separated from the exhaust chamber 13 by means of a support connecting plate 27.

[0084] The separate configuration of cooling chamber 14 and exhaust chamber 13 can be a completely independent configuration, or it can be a configuration of chambers 13 and 14 separated by a wall (e.g., in the form of a support connecting plate 27) as in this design example.

[0085] Cooling chamber 14 includes a coolant that is advantageously liquid or gaseous. Gas flowing in exhaust chamber 13 is cooled by means of the coolant.

[0086] In this exemplary embodiment, the housing cover 7 includes an auxiliary channel 15 for the exhaust unit 9, the auxiliary channel being configured to connect the exhaust opening 10 to the exhaust chamber 13, allowing gas to flow through it. The auxiliary channel 15 also serves to deflect the flow because the exhaust opening 10 is nearly perpendicular to the inflow opening 17 of the exhaust chamber 13. To prevent gas from escaping upstream of the exhaust chamber 13 and downstream of the exhaust opening 10, a sealing element 18 is provided between the auxiliary channel opening 16 and the inflow opening 17 of the auxiliary channel 15, which is configured to face the exhaust chamber 13.

[0087] The blasting element 12 is disposed on the side of the housing cover 7 facing the housing container 11, so that in the direction of gas flow, in other words, from the inside 22 of the container into the auxiliary channel 15, it is installed at the front of the auxiliary channel 15.

[0088] Figure 3 and 4 A second exemplary embodiment illustrates a traction battery system 1 according to the invention. The venting unit 9 includes a hollow tube element 19 with a flange 20 configured to face an vent opening 10 for securing the tube element 19, wherein the tube element 19 is configured to create an auxiliary passage 15. The tube element 19 has a funnel-shaped element section 21 configured to face the vent opening 10, by means of which advantageous rapid gas discharge can be achieved. A sealing element 18 may also be provided here between the tube element 19 and the inflow opening 15. The tube element 19 may also be configured as a flexible hose and is therefore resilient.

[0089] Similar to the cooling chamber 14, the exhaust chamber 13, extending in the direction of the longitudinal axis 23 of the longitudinal supports 4; 5, is configured to accommodate the connecting element 24 for holding the substrate 25, which covers the traction battery system 1 relative to the drive surface. In other words, the exhaust chamber 13 includes a connecting surface.

[0090] At this point, it should be noted that the longitudinal axis 23 extends along the longitudinal axis X of the main body, and the longitudinal axis of the main body is configured to be orthogonal to the transverse axis Y and the vertical axis Z of the main body, such as... Figure 1 As shown in the Cartesian coordinate system. Figure 2 and 4 The cross-section shown is along the YZ main axis plane, which is crossed by the main body's transverse axis Y and the main body's vertical axis Z. The cross-section lines drawn should be interpreted according to this YZ main axis plane.

[0091] In an exemplary embodiment not shown in more detail, at one of its two ends 26, the longitudinal support 4;5 includes a cover element that completely closes end 26 and another cover element that closes at least the cooling chamber 14, allowing gas to flow directionally through end 26, which at least releases exhaust chamber 13 and is preferably configured to be opposite to the direction of travel. Alternatively, in other words, the cover element is provided on the end of the longitudinal support 4;5 facing the front of the vehicle body for completely closing the end.

[0092] In another exemplary embodiment, not shown in more detail, a valve (preferably a check valve) is configured between the exhaust port 10 and the inflow port 17, such that gas flowing through the exhaust chamber 13 can be prevented from flowing into one of the module housings 3.

[0093] The rupture element 12 has an advantageously higher pressure resistance relative to the pressure applied to the side of the rupture element 12 configured away from the module housing 3 than relative to the pressure applied to the side of the rupture element 12 configured to face the module housing 3, thereby preventing gas from flowing from the exhaust chamber 13 into another module housing 3. In other words, if one of the rupture elements 12 ruptures, the gas leaving the module housing 3 associated with that rupture element 12 cannot flow into one of the other module housings 3.

[0094] List of reference numerals in the attached figures

[0095] 1 Traction Battery System

[0096] 2 Battery Modules

[0097] 3. Module housing

[0098] 4 First longitudinal support member

[0099] 5 Second longitudinal support member

[0100] 6. Motor Vehicle Module

[0101] 7. Housing cover

[0102] 8. Latch connection

[0103] 9. Exhaust Unit

[0104] 10 Exhaust openings

[0105] 11 Shell Container

[0106] 12 Explosive Elements

[0107] 13 Exhaust Chamber

[0108] 14 Cooling Chamber

[0109] 15 Auxiliary Channels

[0110] 16 Auxiliary channel openings

[0111] 17. Inflow Opening

[0112] 18 Sealing elements

[0113] 19-tube components

[0114] 20 Flange

[0115] 21 Component Section

[0116] 22. The interior of the container

[0117] 23. Longitudinal axis

[0118] 24 Connecting elements

[0119] 25 substrate

[0120] 26 end

[0121] 27 Support connecting plate

[0122] F Direction of travel

[0123] X Main longitudinal axis

[0124] Y-axis of the main body

[0125] Z Main body vertical axis

Claims

1. A traction battery system (1) for a motor vehicle, comprising at least two battery modules (2), each battery module comprising a plurality of batteries, wherein the battery module (2) comprises a module housing (3), the module housing comprising a housing container (11) and at least one housing cover (7), and wherein the battery module (2) comprises an exhaust unit (9) having an exhaust opening (10) and having a bursting element (12), wherein gas is vented from the module housing (3) via the exhaust opening (10), and wherein the traction battery system (1) comprises a first longitudinal support (4) and a second longitudinal support (5) configured to mount supports, the battery module (2) being disposed between the first longitudinal support and the second longitudinal support, and wherein the longitudinal support (4; 5) has an exhaust chamber (13) and a cooling chamber (14), the exhaust chamber being configured to receive and convey gas flowing through the exhaust unit (9). Its features are, A cooling chamber (14) extending along the exhaust chamber (13) is configured separately from the exhaust chamber for cooling the gas flowing in the longitudinal support (4; 5), wherein the separate configuration of the exhaust chamber (13) and the cooling chamber (14) is either a completely independent configuration or a configuration separated by a wall.

2. The traction battery system (1) according to claim 1, Its features are, The cooling chamber (14) is configured to be adjacent to the exhaust chamber (13).

3. The traction battery system (1) according to claim 1 or 2, Its features are, The cooling chamber (14) includes a cooling medium.

4. The traction battery system (1) according to claim 1 or 2, Its features are, The longitudinal support members (4; 5) are produced using an extrusion molding method or in an extrusion process.

5. The traction battery system (1) according to claim 1 or 2, Its features are, In addition to the exhaust chamber (13), the exhaust unit (9) also includes an auxiliary channel (15) disposed between the exhaust opening (10) and the exhaust chamber (13).

6. The traction battery system (1) according to claim 5, Its features are, The auxiliary channel (15) is disposed in the housing cover (7) or in a tube element (19) disposed adjacent to the housing cover (7).

7. The traction battery system (1) according to claim 5, Its features are, A sealing element (18) is disposed between the auxiliary channel (15) and the exhaust chamber (13).

8. The traction battery system (1) according to claim 5, Its features are, The valve is located in the auxiliary channel (15).

9. The traction battery system (1) according to claim 1 or 2, Its features are, The battery modules (2) are arranged in series between the longitudinal supports (4, 5) transversely to the direction of travel (F) of the motor vehicle, wherein in each case only one battery module (2) is arranged in series between the longitudinal supports (4, 5) along the longitudinal axis (23) of the traction battery system (1).

10. The traction battery system (1) according to claim 1 or 2, Its features are, The shell container (11) is produced in the form of a hollow profile in an extrusion process and can be closed on at least one of the open ends of the shell container by means of the shell cover (7).

11. The traction battery system (1) according to claim 1 or 2, Its features are, The connecting element (24) is disposed in the exhaust chamber (13).

12. The traction battery system (1) according to claim 1 or 2, Its features are, The exhaust chamber (13) is completely closed at its end, which is configured to face the front of the main body of the motor vehicle.

13. The traction battery system (1) according to claim 1 or 2, Its features are, The blasting element (12) has higher pressure resistance relative to the pressure applied to the side of the blasting element (12) configured to face away from the module housing (3) than to the pressure applied to the side of the blasting element (12) configured to face the module housing (3).

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