Battery of an electric vehicle

Abstract

Battery of an electric vehicle, comprising a battery cell pack (20) with a plurality of battery cells (22), a battery housing (12) which delimits a housing interior (121), wherein the housing interior (121) is at least partially filled with a potting compound (V1, V2), wherein a separate partition wall element (30) is arranged in the housing interior (121), which is designed in the manner of a plate and has a transverse web (34), wherein a first space (40) is arranged on a first side of the partition wall element (30) and a second space (42) and a third space (44) are arranged on a second side of the partition wall element (30) opposite to the first side, and wherein the second space (42) is separated from the third space by the transverse web (34), wherein between the transverse web (34) and a further battery component (261, 262) running transversely to the transverse web, a (42) there is a gap (46) connecting the third space (44),wherein a casting compound (V2) is arranged at least in the second space (42), and wherein a sealing element (501, 502) is arranged at an end of the transverse web (34) facing the gap (46), which sealing element has a sealing lip (511, 512) angled transversely to the transverse web (34), which rests against the further battery component (261, 262) in such a way that the gap (46) is sealed.

Description

[0001] The invention relates to a battery of an electric vehicle, comprising a battery cell pack with a plurality of battery cells, a battery housing which delimits a housing interior, wherein the housing interior is at least partially filled with a potting compound.

[0002] Such batteries with a battery housing filled with a potting compound are generally known from the prior art. The potting compound is usually used to fix the battery cells in the battery housing, as a heat conductor for heat transfer between the battery cells and the battery housing and / or as a flame retardant to prevent a flame if hot gases escape from at least one of the battery cells in the event of thermal runaway of the battery cell. The battery housing can be filled with a potting compound completely or only in sections, i.e. predefined cavities. If the battery housing is only partially filled with the potting compound, there are also cavities which are left out of the potting compound, i.e. which are not filled with the potting compound.The cavities filled with the potting compound and those left open by the potting compound are typically defined by the same battery components, which are adjacent to one another. For example, DE 10 2023 133 374 B3 discloses a battery with a partition element arranged on an end face of a battery cell stack, wherein the partition element separates at least one cavity to be filled with a fire protection foam and a cavity not to be filled with the fire protection foam. Furthermore, DE 10 2021 103 866 A1 discloses a battery with a partition element arranged on an end face of a battery cell stack, wherein the partition element has a gas-permeable seal, wherein when a higher-viscosity fluid is poured into a space between the battery cell stack and the partition element, the air displaced thereby can escape through the seal.

[0003] Due to assembly and manufacturing tolerances and to ensure the simplest possible assembly, there are gaps between the battery components that delimit the cavities. This creates the risk that the liquid potting compound will flow into the cavity to be filled with the potting compound during the filling process, into the cavity that is specifically not intended to be filled with the potting compound.

[0004] The object of the invention is to provide a battery of an electric vehicle in which the different spaces, ie the cavities filled with the potting compound and those left open by the potting compound, can be separated from one another in a simple manner and an overflow of the potting compound into the space in which no potting compound is to be present can be avoided in a simple and reliable manner.

[0005] The problem is solved by the features of claim 1.

[0006] According to the invention, a separate partition wall element is arranged in the housing interior, separating three compartments from one another. A first compartment is arranged on a first side of the partition wall element, and a second compartment and a third compartment are arranged on a second side of the partition wall element opposite the first side. To separate the second compartment from the third compartment, the generally plate-shaped partition wall element has a transverse web oriented perpendicular to the base extension of the partition wall element, which extends over the entire length of the partition wall element and thereby separates the two compartments arranged on the second side of the partition wall element from one another.

[0007] A casting compound is arranged in the second chamber. The third chamber does not contain any casting compound, i.e., it is not filled with a casting compound. Thus, the partition wall element separates three chambers from each other, with at least one of the three chambers being filled with a casting compound.

[0008] Between the crosspiece and another battery component, which runs perpendicular to the crosspiece, there is a gap connecting the second chamber to the third chamber, for example due to assembly and manufacturing tolerances. This gap creates the risk that the potting compound, which is in a liquid state during the filling process into the second chamber, could flow through the gap into the third chamber, which should be free of potting compound.

[0009] To prevent the potting compound from flowing into the third space, a sealing element is arranged at the end of the crosspiece facing the gap. The sealing element has an elastically deformable sealing lip angled transversely to the crosspiece, which rests against the other battery component in such a way that the gap is sealed.

[0010] During the filling process, the second chamber is completely filled with the potting compound, whereby the potting compound preferably acts on the sealing element in such a way that the sealing lip is loaded, thereby deforming it and pressing it against the other battery component. Thus, filling the second chamber with the potting compound automatically seals the gap between the crosspiece and the other battery component.

[0011] This provides a simple and cost-effective way to prevent the casting compound from flowing from the second room into the third room.

[0012] In a preferred embodiment, the first chamber is filled with a first potting compound, and the second chamber is filled with a second potting compound. Preferably, each potting compound is a flame-retardant material. This reduces the risk of ignition of a gas escaping from one of the battery cells due to thermal runaway, thereby preventing a fire in the battery. Furthermore, the potting compound can reduce the risk of contaminating other battery cells in the battery pack by preventing the hot gases from overflowing to the other battery cells through the potting compound.

[0013] Preferably, the first and second casting compounds are identical. Alternatively, the casting compounds can differ from each other, allowing the use of casting compounds with different material properties, thus allowing the casting compounds to be optimally tailored to the application.

[0014] Preferably, the partition element is made in one piece. In a preferred embodiment, the partition element is made of plastic. In particular, the partition element is made of a thermoplastic material and is manufactured by injection molding. This allows the partition element to be manufactured in a simple and cost-effective manner.

[0015] Preferably, the sealing element is manufactured in one piece with the partition element. The sealing element is manufactured during the manufacturing process of the partition element, thereby reducing the manufacturing and assembly costs of the battery.

[0016] The partition wall element is preferably arranged on an end face of the battery cell pack, the first space being delimited at least by the battery cells and the partition wall element. The first space is also delimited by further battery components. In particular, the first space is delimited, in addition to the partition wall element, by two plate-like insertion aid elements used to install the battery cell pack in the battery housing, by the battery housing and / or by a battery cell carrier. The insertion aid elements are arranged on the two outermost battery cells of the battery cell pack and project beyond the battery cell pack and the partition wall element transversely to the stacking direction. The second and third spaces are also delimited, in addition to the partition wall element, by the two insertion aid elements, i.e. by the sections of the insertion aid elements projecting beyond the battery cell pack, by the battery housing and / or by the battery cell carrier.

[0017] The battery housing comprises, in particular, a base body constructed as an extruded profile with two open sides and two covers that close the open sides of the base body. During the assembly process, the battery cell pack is inserted into the battery housing through one of the open sides, and the open sides are then closed with a cover.

[0018] In a preferred embodiment, a frame-like battery cell carrier is arranged on the battery cell pack, on which the partition element is arranged. The battery cell carrier is preferably arranged on both sides of the battery cell pack and serves in particular to hold the battery cell pack together. Additionally, an electrical connection unit is arranged on the battery cell carrier in the region of the second space. In a preferred embodiment, the partition element is locked to the battery cell carrier, which can simplify the assembly of the partition element.To lock the partition element to the battery cell carrier, the partition element preferably has a plurality of locking elements and at least one support element. During assembly of the partition element to the battery cell carrier, the partition element is moved translationally in the direction of the battery cell carrier until the support element rests against the battery cell carrier. Upon the support element resting against the battery cell carrier, the locking elements engage in the openings of the battery cell carrier. Alternatively, the partition element can also be connected to the battery cell carrier using other connection techniques, such as screwing or gluing.

[0019] Preferably, at two mutually opposite ends of the partition wall element there is a gap connecting the second space to the third space, wherein a sealing element is arranged at each of the two ends of the transverse web facing a further battery component.

[0020] An embodiment of the invention is explained in more detail with reference to the drawing. Fig. 1 shows a section of a battery in perspective view, Fig. 2 shows a section of the battery from Fig. 1, Fig. 3a shows the battery from Fig. 1 and Fig. 2 during a filling process of a first casting compound into a first space, and Fig. 3b shows the battery from Fig. 1 and Fig. 2 during a filling process of a second casting compound into a second space.

[0021] Fig. Figure 1 shows a battery 10, in particular a traction battery of an electric vehicle. The battery 10 can also be merely a part of a traction battery of the electric vehicle, i.e., a battery module that, together with other battery modules, forms the traction battery.

[0022] The battery 10 has a battery housing 12 which is in the Fig. 1 is indicated by dashed lines so that the battery components arranged in the battery housing 12 are visible. The battery housing 12 has, for example, a base body designed as an extruded profile with two side walls 122, 125, a cover 124, and a base 123. The two open sides of the base body are each closed by a cover 126. The battery housing 12 defines a housing interior 121.

[0023] A battery cell pack 20 with a plurality of battery cells 22 stacked in the stacking direction is arranged in the housing interior 121. The battery cell pack 20 is held together by a frame-like battery cell carrier 24, which is permeable to fluids. An insertion aid element 261, 262 is arranged on each of the two outermost battery cells 22 of the battery cell pack 20. These insertion aid elements serve to simplify the insertion of the battery cell pack 20 through one of the two open sides of the main body of the battery housing 12 into the housing interior 121. An electrical connection element 28 is also arranged on the battery cell carrier 24 to electrically couple the battery 10 to another component, wherein all battery cells 22 are interconnected and electrically connected to the electrical connection element 28.

[0024] A partition element 30 is arranged on a side of the battery cell carrier 24 facing away from the battery cells 22. The partition element 30 is plate-shaped and connected to the battery cell carrier 24 via several snap-in connections. The partition element 30 is made of plastic and manufactured by injection molding.

[0025] The partition wall element 30 is designed such that a plurality of spaces 40, 42, 44 of the housing interior 121 are separated from one another, wherein a first space 40 is arranged on a side facing the battery cell pack 20, i.e., an end face 201 of the battery cell pack 20, and is delimited by the partition wall element 30, the battery cell pack 20, the two insertion aid elements 261, 262, and the battery housing 12. The partition wall element 30 has a plurality of predetermined failure regions 32. A second space 42 and a third space 44 are arranged on a side of the partition wall element 30 facing away from the battery cell pack 20, wherein the third space 44 is separated from the second space 42 by a transverse web 34. The cover 126 rests against the free end of the transverse web 34 facing away from the battery cell pack 20 and, together with the separating element 30, the insertion aid elements 261, 262 and the battery housing 12, delimits the second space 42 and the third space 44.The transverse web 24, with its two ends aligned in the stacking direction of the battery cell pack 20, adjoins an insertion aid element 261, 262, wherein, due to inevitable manufacturing and assembly tolerances, a gap 46 is present between the insertion elements 261, 262 and the transverse web 34 of the separating element 30. In . Fig. 2, the gap 46 with a gap width S is shown in an enlarged view.

[0026] In a fully assembled state of the battery 10, the first chamber 40 and the second chamber 42 are each filled with a potting compound V1, V2. The potting compounds V1, V2 are identical and made of a flame-retardant material, in particular a foam. Alternatively, the potting compounds V1, V2 can be designed differently from one another. The potting compounds V1, V2 serve to ensure that, in the event of a thermal runaway of one of the battery cells 22 and the resulting escape of hot, electrically conductive gases, other battery cells 22 of the battery cell pack 20 are not connected, and a short circuit on electrically conductive, exposed components, in particular on the electrical connection element 28, is prevented.

[0027] During the manufacture of the battery 10 or during the assembly of the battery 10, the two potting compounds V1, V2 are successively filled into the spaces 40, 42, whereby first the first space 40 is filled with the first potting compound V1 and then the second space 42 is filled with the second potting compound V2. Fig. 3a, the arrows indicate the filling of the first casting compound V1 into the first chamber. Fig. In Figure 3b, the arrows indicate the filling of the second casting compound V2 into the second chamber 42. The casting compounds V1 and V2 are poured into the chambers 40 and 42 in a liquid state and then solidify.

[0028] When pouring the second casting compound V2 into the second chamber 42, the problem arises that the liquid second casting compound V2 would flow through the gap 46 into the third chamber 44, in which no casting compound should be present. To prevent the second casting compound V2 from overflowing into the third chamber 44, the partition element 30 has a sealing element 501, 502 at each end of the transverse web 34 facing an insertion aid element 261, 262. The sealing elements 501, 502 are molded onto the partition element 30 and thus manufactured in one piece with the partition element 30. The sealing elements 501, 502 each have an elastically deformable sealing lip 511, 512, which extends at an angle to the crosspiece 34 and, in the final assembled state of the battery 10, rests against the respective insertion aid element 261, 262.

[0029] During the filling process, the second chamber 42 is completely filled with the second potting compound V2, whereby the second potting compound V2 acts on the sealing elements 501, 502 or on the sealing lips 511, 512 in such a way that the sealing lips 511, 512 are loaded and deformed and pressed against the insertion aid elements 261, 262. Thus, filling the second chamber 42 with the second potting compound V2 automatically seals the gap 46 present between the transverse web 34 and the insertion aid elements 261, 262. This prevents the second potting compound V2 from flowing into the third chamber 44.

Claims

[1] Battery of an electric vehicle, with a battery cell pack (20) with several battery cells (22), a battery housing (12) which delimits a housing interior (121), wherein the housing interior (121) is at least partially filled with a potting compound (V1, V2), characterized by , that a separate partition wall element (30) is arranged in the housing interior (121), which is designed in a plate-like manner and has a transverse web (34), wherein a first space (40) is arranged on a first side of the partition wall element (30) and a second space (42) and a third space (44) are arranged on a second side of the partition wall element (30) opposite the first side, and wherein the second space (42) is separated from the third space by the transverse web (34), wherein a gap (46) connecting the second space (42) to the third space (44) is present between the transverse web (34) and a further battery component (261, 262) running transversely to the transverse web, wherein a potting compound (V2) is arranged at least in the second space (42), and wherein a sealing element (501, 502) is arranged at an end of the transverse web (34) facing the gap (46), said sealing element having a sealing lip (511, 512) angled transversely to the transverse web (34) and resting against the further battery component (261, 262) in such a way that the gap (46) is sealed. [2] Battery according to claim 1, characterized by that the sealing lip (511, 512) is loaded by the casting compound (V2) in such a way that the sealing lip (511, 512) bears against the further battery component (261, 262). [3] Battery according to claim 1 or 2, characterized by that a first potting compound (V1) is arranged in the first space (40) and a second potting compound (V2) is arranged in the second space (42). [4] Battery according to claim 3, characterized by that the first casting compound (V1) and the second casting compound (V2) are the same or different from each other. [5] Battery according to one of the preceding claims, characterized bythat the partition wall element (30) is made in one piece. [6] Battery according to one of the preceding claims, characterized by that the partition element (30) is made of plastic. [7] Battery according to one of the preceding claims, characterized by that the sealing element (501, 502) is made in one piece with the partition wall element (30). [8] Battery according to one of the preceding claims, characterized by that the partition wall element (30) is arranged on an end face (201) of the battery cell pack (20), wherein the first space (40) is delimited at least by the battery cells (22) and the partition wall element (30). [9] Battery according to one of the preceding claims, characterized by that a frame-like battery cell carrier (24) is arranged on the battery cell pack (20), on which the partition wall element (30) is arranged. [10] Battery according to claim 9, characterized bythat the partition element (30) is locked to the battery cell carrier (24). [11] Battery according to one of the preceding claims, characterized by that at two mutually opposite ends of the partition wall element (30) there is a gap (46) connecting the second space (42) to the third space (44), wherein a sealing element (501, 502) is arranged at each of the two ends of the transverse web (34) facing a further battery component (261, 262).

Images