High-voltage battery for a vehicle

Abstract

High-voltage battery for an at least partially electrically powered vehicle, the battery housing (1) of which has a housing upper part (3) and a housing base (5) with an integrated cooling system (19), wherein at least one battery module (11) is arranged in the battery housing (1), wherein an air gap (15) is present between the battery module (11) and the housing base (5) due to tolerances, which is filled with thermally conductive material (17), and wherein the housing base (5) is a component separate from the housing upper part (3), which is connected to the housing upper part (3) at a joint (F), characterized in that the battery module (11) is fixedly connected to the housing upper part (3), and that a housing base lifting system (21) is assigned to the joint (F), in which the housing base (5) is guided in the upward direction of the battery (z) over an adjustment range (Δz).so that the housing base (5) can be adjusted to any stroke position (M) within the adjustment range (Δz) and fixed there.

Description

[0001] The invention relates to a high-voltage battery for a vehicle that is at least partially electrically powered according to the preamble of claim 1 and to a method for mounting such a high-voltage battery according to claim 9.

[0002] In such a high-voltage battery, battery cells are grouped into cuboid-shaped battery modules. A number of these battery modules are installed in the battery housing of the high-voltage battery. The battery modules are each clamped to fixed module screw points within the housing.

[0003] In an example high-voltage battery, the battery housing comprises an upper housing section and a lower housing section with an integrated cooling system. At least one battery module is arranged within the battery housing and is rigidly connected to the upper housing section. Due to manufacturing tolerances, an air gap exists between the battery module and the lower housing section, which is filled with thermally conductive material. The lower housing section is a separate component from the upper housing section and is connected to it at a joint.

[0004] In the prior art, the high-voltage battery is assembled as follows: First, in a module placement process, the still empty housing top is fitted with at least one battery module. The battery module is clamped to the housing top at fixed module screw points. Subsequently, a joining process takes place in which the housing bottom (for example, by means of a screw connection) is attached to the housing top. In the prior art, the housing bottom with its joining flange is brought into contact with a corresponding joining flange on the housing top and screwed together. Due to component tolerances in the housing bottom and the housing top, as well as manufacturing tolerances, an air gap remains between the battery module and the housing bottom, which can be filled with flowable thermal paste after battery assembly. A thermally conductive mat can also be used instead of thermal paste.In this case, the bottom of the housing is attached to the top of the housing with the thermally conductive mat in between.

[0005] Filling the air gap with the thermal conductivity material requires a lot of material and leads to an increased component weight of the high-voltage battery.

[0006] A battery assembly is known from DE 10 2016 216 050 A1. A battery with a thermal interface for a motor vehicle is known from DE 20 2019 101 971 U1. A method for cooling a traction battery is known from DE 10 2015 214 652 A1.

[0007] From DE 10 2017 111 315 A1, generic, sealed battery pack designs are known. DE 10 2014 226 260 A1 discloses a battery cell, a battery module, and a use thereof. From DE 10 2016 222 094 A1, a battery housing for a traction battery of an electrically powered vehicle is known. US 2012 / 0164500 A1 discloses a vehicle battery housing. From US 2014 / 0287289 A1, electrified battery assemblies are known.

[0008] The object of the invention is to provide a high-voltage battery for a vehicle and a method for assembling such a high-voltage battery, in which, compared to the prior art, the material expenditure for the thermal conductivity material and the component weight of the high-voltage battery can be reduced in a simple manner.

[0009] The problem is solved by the features of claim 1 or 9. Preferred embodiments are disclosed in the dependent claims.

[0010] The invention is based on the fact that, in the prior art joining process, the housing base is attached to the housing upper part without height adjustment, so that a reduction of the air gap due to displacement of the housing base in the vertical direction of the battery is not possible. Against this background, the joining point according to the invention between the housing upper part and the housing base according to claim 1 has a housing base lifting system in which the housing base is guided in the vertical direction of the battery over a predefined adjustment range. In this way, the housing base can be adjusted to any lifting position within the adjustment range and fixed there.

[0011] For example, during the battery assembly process, the housing base can be adjusted by means of the housing base lifting system over a stroke range to a specific assembly lifting position. In this position, the housing base, possibly with thermal interface material inserted, can be brought flush with the battery module. The remaining air gap results from unevenness in the housing base and / or height tolerances between the battery modules. This residual air gap is reduced to a minimum, thereby also minimizing the amount of thermal interface material required.

[0012] In a simple technical implementation, the housing base lifting system can have a guide channel with a hollow profile open in the vertical direction of the battery on a first joining partner, in particular the housing top part. On a second joining partner, in particular the housing base, a guide web can be formed that is adjustable in its stroke within the guide channel. In a simple technical implementation, the guide channel can be formed on an edge of the housing top part facing the housing base. The guide web, on the other hand, can be formed on a side wall that extends upwards from the edge of the flat housing base.

[0013] To fix the housing base in its mounting position, the high-voltage battery can have at least one preload spring. Using the preload spring, the housing base can be pressed against a predefined height stop, in particular against the battery module. For example, the preload spring can be mounted at one spring base point on the upper part of the housing, while the other spring base point presses against the housing base.

[0014] Alternatively, an auxiliary joining element can be provided to fix the housing base in its assembly stroke position. With its aid, the housing base, in the assembly stroke position, can be brought into a force-fit and / or positive-locking connection with the housing upper part.

[0015] In a preferred embodiment, the auxiliary joining element can be a screw bolt by means of which the housing base, adjusted in its mounting stroke position, can be screwed to the housing upper part. Preferably, the screw axis of the screw bolt can be aligned perpendicular to the vertical direction of the battery.

[0016] In a space-saving design variant, the auxiliary joining element can be a fastening clip arranged in the guide channel, into which the guide bar can be inserted, thereby creating a positive locking connection.

[0017] A sealant can also be positioned in the guide channel to ensure a liquid-tight seal of the battery interior.

[0018] In a battery assembly process according to the invention, the first step is module placement, in which the battery module is inserted into the still empty housing upper part and screwed there at housing-fixed module screw points. Subsequently, optionally with the insertion of thermally conductive material, the housing base with its guide rib is inserted into the guide channel of the housing upper part and adjusted via a stroke to a mounting position. By way of example, in the mounting position, the housing base can be brought up to a stop against the battery module, optionally with the insertion of thermally conductive material.

[0019] Exemplary embodiments of the invention are described below with reference to the accompanying figures.

[0020] They show: Fig. 1 in a roughly schematic partial sectional view of a high-voltage battery in its assembled state; Fig. 2, Fig. 3 to Fig. 4 views each, illustrating a battery assembly process; Fig. 5 a joint according to a first embodiment variant; and Fig. 6 a joint according to a second design variant.

[0021] In the Fig. Figure 1 shows a high-voltage battery in its assembled state. The high-voltage battery has a battery housing 1 with a housing top 3 and a housing bottom 5. In the Fig. Figure 1 shows the housing upper part 3 as an example of a shell-shaped design, with a housing cover 7 on the upper side from which a circumferential side wall 9 projects. A joint F is formed at the lower edge of the side wall 9 of the housing upper part 3, at which the housing base 5 is attached to the housing upper part 3. Battery modules 11 are inserted inside the battery, of which only one battery module 11 is indicated in the figures. The battery module 11 is in the Fig. 1 is screwed to the housing top 3 at a housing-fixed module screw point 13. Due to tolerances, an air gap 15 exists between the battery module 11 and the housing base 5, which is filled with a thermally conductive material 17. A cooling system 19 is also integrated into the housing base 5, which is in thermal contact with the battery module 11 via the thermally conductive material 17 in the air gap 15.

[0022] As from the Fig. As can be seen further in Figure 1, a housing base lifting system 21 is assigned to the joint F. The housing base lifting system 21 has a guide channel 23 formed at the lower edge of the side wall 9 of the housing upper part 3, the hollow profile of which is open in the vertical direction z towards the bottom of the battery. The guide channel 23 has an approximately groove-shaped cross-section with an outer channel wall 25 ( Fig. 2) and an inner channel wall 27 ( Fig. 2) realized. In addition, the housing base lifting system 21 has a guide web 29 which extends upwards from the edge of the flat housing base 5 in the battery vertical direction z. The guide web 29 of the housing base 5 is mounted in the guide channel 23 of the housing upper part 3 so as to be adjustable in stroke. In the Fig. Figure 2 shows that the joining point F is implemented as an example of a screw connection, where a screw bolt clamps the guide web 29 on the bottom of the housing to the guide channel 23 of the upper part of the housing 3. The screw axis of the screw connection is oriented transversely to the vertical direction z of the battery.

[0023] The following will be based on the Fig. 2, Fig. 3, Fig. 4 to Fig. 5. A battery assembly process is described: Accordingly, in the Fig. 2. First, the still empty housing upper part 3 is provided with the housing opening facing upwards. In a module placement process, the battery module 11 is inserted into the housing upper part 3 in a placement direction I and clamped in a screw operation with the housing-fixed module screw point 13.

[0024] Then, according to the Fig. 3 the thermal conductivity mat 17 is placed on the battery module 11 and a joining process takes place in which the housing base 5 is in the joining direction II ( Fig. 3) is attached to the housing upper part 3, with the thermally conductive mat 17 interposed. During the joining process, the housing base guide rib 29 is inserted into the guide channel 23 of the housing upper part 3 in the battery vertical direction z, so that the guide rib 29 of the housing base 5 moves in the guide channel 23 of the housing base lifting system 21 over a predefined adjustment range Δz ( Fig. 4) is guided in a stroke-adjustable manner. In this way, the housing base 5 can be moved into a mounting stroke position M ( Fig. 4) stroke adjustment, in which the housing base 5 is pressed against the battery module 11 with the thermal conductivity mat 7 (alternatively also without thermal conductivity mat 7) in place.

[0025] The remaining air gap 15, resulting from unevenness in the housing base or height tolerances between battery modules 11, is therefore reduced to a minimum. Accordingly, the amount of thermal conductivity material 17 is also reduced to a minimum.

[0026] After positioning the housing base 5 in its mounting stroke position M ( Fig. 4) A screwing process takes place in which the guide channel 23 of the housing upper part 3 is screwed to the guide web 29 of the housing base 5.

[0027] In the preceding embodiment, a screw bolt is used as an auxiliary joining element. Instead, in the Fig. 5 The auxiliary joining element is, for example, a space-saving fastening clip 31 (for example, a scraper clip) arranged in the guide channel 23. The fastening clip 31 is in the Fig. 5 is shown in its undeformed state. In the joining process, the fastening clip 31 is brought into a positive-locking connection with the guide rib 29 of the housing base 5. As can be seen from the Fig. As further shown in Figure 5, a sealant 33 is additionally arranged in the guide channel 23, which separates the battery interior from the environment in a liquid-tight manner.

[0028] In the Fig.6 The auxiliary joining element is designed as a spring clip 35, which acts as a preload spring, biasing the housing base 5 into its assembly stroke position M. The spring clip 35 is mounted to the housing upper part 3 with a spring base 37, while the opposite spring base 39 presses the housing base 5 against a height stop, in particular against the battery module 11. Reference symbol list 1 battery case 3 Housing top 5 Case bottom 7 Case Cover 9 Case side panel 11 Battery module 13 Module screw point 15 air gap 17 Thermal conductivity material 19 Cooling system 21 Housing base lifting system 23 Guide channel 25 outer channel wall 27 inner channel wall 29 Guide bridge 31 fastening clips 33 Sealant 35 spring clip 37, 39 Spring base I Setting direction II Leading direction Δz adjustment range M Mounting lift position

Claims

High-voltage battery for an at least partially electrically powered vehicle, the battery housing (1) of which has a housing upper part (3) and a housing base (5) with an integrated cooling system (19), wherein at least one battery module (11) is arranged in the battery housing (1), wherein an air gap (15) is present between the battery module (11) and the housing base (5) due to tolerances, which is filled with thermally conductive material (17), and wherein the housing base (5) is a component separate from the housing upper part (3), which is connected to the housing upper part (3) at a joint (F), characterized in that the battery module (11) is fixedly connected to the housing upper part (3), and that a housing base lifting system (21) is assigned to the joint (F), in which the housing base (5) is guided in the vertical direction (z) of the battery over an adjustment range (Δz).so that the housing base (5) can be adjusted to any stroke position (M) within the adjustment range (Δz) and fixed there. High-voltage battery according to claim 1, characterized in that in a battery assembly process the housing base (5) in the housing base lifting system (21) is adjustable over a lifting path to an assembly lifting position (M), and that in the assembly lifting position (M) the housing base (5) is brought into contact with the battery module (11) or with another height stop under the interposition of the heat conducting material (17). High-voltage battery according to claim 1 or 2, characterized in that the housing bottom lifting system (21) has a guide channel (23) with a hollow profile open in the battery vertical direction (z) and a guide web (29) guided in the guide channel (23) in a stroke-adjustable manner, and that the guide channel (23) is formed on the housing upper part (3) and the guide web (29) is formed on the housing bottom (5). High-voltage battery according to claim 3, characterized in that the guide channel (23) is formed on an edge of the housing upper part (3) facing the housing base (5), and that the guide web (29) is formed on a side wall raised at the edge of the housing base (5). High-voltage battery according to one of the preceding claims, characterized in that an auxiliary joining element (31; 35) is provided to fix the housing base (5) in its mounting stroke position (M), by means of which the housing base (5) is secured in its mounting stroke position (M), and that the auxiliary joining element is a preload spring (35) by means of which the housing base (5) is pressed against the battery module (11), and that the preload spring (35) can be supported between the housing upper part (3) and the housing base (5). High-voltage battery according to claim 5, characterized in that the auxiliary joining element is a screw bolt by means of which the housing base (5) located in its assembly stroke position (M) can be screwed to the housing top part (3). High-voltage battery according to claim 5, characterized in that the auxiliary joining element is a fastening clip (31) arranged in the guide channel (23), which can be brought into a positive locking connection with the guide web (29). High-voltage battery according to one of the preceding claims, characterized in that in the battery assembly process, the battery module (11) is first inserted into the housing upper part (3) in a module setting process step in a setting direction (I), and is subsequently connected to the housing upper part (3) at module screw points (13), and that in a subsequent joining process step, the housing bottom (5) is joined to the housing upper part (3) in a joining direction (II) and with the thermal conductivity material (17) interposed. Method for assembling a high-voltage battery according to one of the preceding claims.

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