Battery mold frame of a traction battery of a motor vehicle and corresponding traction battery

Abstract

A battery mold frame of a traction battery is described for receiving a plurality of battery cells which have a non-planar outer surface, wherein the battery mold frame has at least one frame profile, wherein the frame profile has a frame side aligned with the battery cells, wherein formations are formed on this frame side.

Description

A battery form frame of a traction battery of a motor vehicle and a corresponding traction battery are described.Battery frames of a traction battery of a motor vehicle and corresponding traction batteries of the type mentioned at the beginning are known in the prior art.Battery cells must be interconnected and assembled in large numbers in a traction battery of a motor vehicle. Such a traction battery is generally surrounded by structural parts which, in the event of a crash, provide protection against intrusion and other, severe damage and thus protect the battery cells.In the prior art, such structural parts are regularly frames made of linearly shaped profiles, e.g. extruded profiles.DE 10 2022 000 360 A1 discloses a multi-cell housing for an electrical energy store having a plurality of electrochemical individual cells having a plurality of receptacles, each receptacle being configured to form a separate receptacle of in each case one individual cell. According to the invention, it is provided that a housing body is produced from an extruded profile, into which side plates and end plates laterally enclosing the housing body are integrated, a base element closing at least one receptacle on the base side is weldable or welded to an edge region delimiting the at least one receptacle, a cover element closing at least one receptacle on the head side in a fluid-tight manner is provided, wherein adjacent receptacles are in sections adjacent to one another and a wall in an adjacent region is assigned to both adjacent receptacles and separates them from one another.In particular in the construction of round cells, linearly shaped profiles such as extruded profiles, as are currently used, have considerable disadvantages on account of their geometry and arrangement. Inhomogeneous spaces are inevitably produced between the round cells and the profiles. It follows from this that a casting compound used for fastening the round cells to the profiles is likewise distributed with unequal thickness. This results in an uneven temperature transmission behavior, which can cause mechanical stresses and damage. Furthermore, large masses of casting compound are required to fill up the large spaces between the profiles and the round cells, so that the weight of corresponding traction batteries increases.The object is therefore to further develop a battery form frame of a traction battery of a motor vehicle and corresponding traction batteries of the type mentioned at the beginning to the effect that a higher structural strength and higher crash safety with a saving in weight and space with better thermal properties are provided.The object is achieved by a battery form frame of a traction battery of a motor vehicle according to Claim 1 and a traction battery according to Claim 8 which is subordinate to the invention.A battery shaped frame of a traction battery for receiving a plurality of battery cells which have a non-planar outer surface is described, wherein the battery shaped frame has at least one frame profile, wherein the frame profile has a frame side aligned with the battery cells, wherein formations are formed on the frame side.The battery shaped frame can have a plurality of correspondingly configured frame profiles. The frame profiles can have a straight extension direction, be angled or bent. The frame profiles can form a rectangle or another geometry individually or in conjunction with other, in particular similar, frame profiles. The frame profiles can be connected to one another, for example adhesively bonded, screwed, riveted, welded, latched or the like.The frame side aligned with the battery cells is usually an inner side of the frame profiles. However, it is also conceivable in some configurations for a battery shaped frame to have intermediate struts which likewise have other frame sides aligned with the battery cells, in particular opposite frame sides, which can be provided with formations in each case.The corresponding frame profile essentially forms a slightly enlarged negative of the external geometry of the battery cells used.The formations on the frame sides of the battery shaped frame aligned with the battery cells each bring about a uniform gap between frame profile and battery cells, which gap can be filled with a uniformly thick layer of potting material.By means of the battery mold frame described here, uniform heat transport can be achieved, voltage and / or temperature peaks due to uneven heat transport can be avoided.Furthermore, on the one hand, a higher structural strength and stability result from better force transmission between the battery shaped frame and the battery cells and thus increased crash safety. On the other hand, the formations of the battery forming frame also result in a higher structural rigidity of the internal component.Space can also be saved since the battery cells can be arranged closer to the battery shape frame than in the case of straight battery shape frames without protrusions.Because the potting compound layers can be thinner than in conventional battery mold frames, weight is furthermore saved.In a first further embodiment, it is provided that the formations are at least sectionally congruent with the battery cells or these at least sectionally represent an enlarged contour of the battery cells.In this way, a gap between the battery mold frame and the battery cells can be accurately adjusted.In a further, further embodiment, it is provided that the formations are cylinder sections.This embodiment is particularly suitable for round cells.In a further refinement, it is provided that the formations have, in plan view, a formation radius which is greater than a battery cell radius of the battery cells.Thus, there remains sufficient space for introducing the potting compound.The forming radius can be selected in particular such that the battery cells are arranged in a uniform grid up to the edge, that is to say up to the battery forming frame.In a further, further embodiment, it is provided that the formations are arranged next to one another and merge into one another without edges.Owing to the edge-free transitions, potting compound or adhesive can flow and distribute without a barrier without undesired cavities or bubbles occurring.In a further, further embodiment, it is provided that the frame profile is a hollow profile, wherein the formations are produced by high-pressure forming.A suitable high-pressure forming process is in particular hydroforming.Hollow profiles have the advantage that they are stable and light and that the cavities can be used for further purposes, for example for the integration of a cooling system.Metallic materials, in particular aluminum and / or aluminum alloys, are particularly suitable for production by internal high-pressure forming.In a further, further embodiment, it is provided that the frame profile has at least one tapered or tapered end section which is or can be connected to a further frame profile.Plug connections can thereby be integrated into the frame profile. Such integrated plug connections make it possible to produce the frame from individual parts, so that the size of a battery mold frame can be varied as desired, as a result of which different vehicle types and battery dimensions can be equipped with a large number of identical parts.Corresponding tapers can be introduced directly during the forming process.A first independent subject matter relates to a traction battery having at least one battery form frame of the type described above and a plurality of battery cells held in the battery form frame.In some configurations, the battery forming frame can be surrounded by a further frame made of linear profiles, for example extruded profiles, in order to further increase the strength.In a first, further embodiment, it is provided that the battery cells are round cells each having a battery cell radius, wherein the formations are cylinder sections having a formation radius, wherein the formation radius is between 0.1 mm and 15 mm larger than the battery cell radius.In a further, further embodiment, it is provided that the battery cells are glued to the battery mold frame by means of a potting material.Further advantages, features and details are evident from the following description, in which--possibly with reference to the drawing--at least one exemplary embodiment is described in detail. Identical, similar and / or functionally identical parts are provided with the same reference numerals.They show schematically: FIG. 1 shows a perspective view of a detail of a traction battery with a battery form frame and an arrangement of round cells; FIG. 2 shows a top view of the traction battery from FIG. 1 ; FIG. 3 shows an enlarged detail from FIG. 2 ; FIG. 4 shows a sectional view of an end section of a frame profile which is inserted into an end section of a further frame profile; FIG. 5 shows a perspective view of a detail of a traction battery with a battery shaped frame and an arrangement of round cells according to the prior art, and FIG. 6 shows a plan view of the traction battery from the prior art from FIG. 5.FIG. 1 shows a perspective view of a detail of a traction battery 2.The traction battery 2 has a battery shape frame 4, of which a frame profile 6 can be seen in FIG. 1, and an arrangement of battery cells 8, in the present case round cells. The battery cells 8 are arranged in a uniform matrix.The frame profile 6 has a frame side 10 which is aligned with the battery cells 8 and in which formations 12 are formed. The shapes 12 are matched in their geometry to outer surfaces 14 of the battery cells 8.The frame profile 6 is designed as a hollow profile, wherein the formations 12 are formed by means of hydroforming methods.FIG. 2 shows a top view of the traction battery of FIG. 1.The frame profile 6 borders at right angles on a frame profile 6' which are connected to one another.Battery molded frames 4 and battery cells 8 are encapsulated with the aid of an encapsulation material 16 and thus form a unit. Due to the formations 12, the potting material 16 has a comparatively homogeneous thickness, which has a positive effect on the heat transport.FIG. 3 shows an enlarged detail from FIG. 2.The formations 12 form, in plan view, circular sections of circles which have a common center with the battery cells 8 which are circular in plan view. A center Z of the forming radius D therefore coincides with the center Z of the battery cell 8 provided with reference numerals in FIG. 3. The battery cells 8 have a battery cell radius R. A minimum distance A between adjacent battery cells 8 corresponds to a difference between forming radius D and battery cell radius R, whereby a potting material thickness that is as uniform as possible is achieved.FIG. 4 shows a sectional view of an end section 18 of a further frame profile 6'' which is inserted into an end section 20 of the frame profile 6.In the hydroforming process, the end portion 18 is formed with a taper 22 to allow it to be inserted into the end portion 20, or vice versa.The frame profiles 6, 6" are bonded in a fluid-tight manner by means of an adhesive layer 24, whereby it becomes possible to use an inner region 26 for fluid guidance, for example in order to conduct a coolant through the frame profiles 6, 6". The adhesive layer 24 also structurally connects the frame profiles 6, 6'' to one another, so that the overall connection has a high structural strength.FIG. 5 shows a perspective view of a detail of a traction battery 102 having a battery frame 106 and an arrangement of round battery cells 108 according to the prior art.FIG. 6 shows a plan view of the traction battery 102 from the prior art from FIG. 5.The battery frame 106 is flat, such that the battery cells 108 have non-uniform distances from the battery frame 106 and in particular larger gaps 111 are formed, which would have to be filled with potting material.Although the invention has been illustrated and explained in more detail by preferred exemplary embodiments, the invention is not restricted by the disclosed examples and other variations can be derived therefrom by the person skilled in the art without departing from the scope of protection of the invention. It is therefore clear that a large number of possible variations exist. It is also clear that embodiments mentioned by way of example represent only examples which are not to be understood in any way as limiting, for example, the scope of protection, the possible applications or the configuration of the invention. Rather, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete terms, wherein the person skilled in the art, having knowledge of the disclosed inventive idea, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without departing from the scope of protection defined by the claims and their legal equivalents, such as a further explanation in the description.List of reference characters2 Traction battery 4 Battery shaped frame 6, 6', 6" Frame profile 8 Battery cells 10 Frame side 12 Formations 14 Outer surface 16 Potting material 18, 20 End section 22 Taper 24 Adhesive layer 26 Inner region 102 Traction battery 106 Battery frame 108 Battery cells 111 Gap A Distance D Formation radius R Battery cell radius Z CenterReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2022 000 360 A1

[0005]

Claims

Battery shaped frame (4) of a traction battery (2) for receiving a plurality of battery cells (8) which have a non-planar outer surface (14), wherein the battery shaped frame (4) has at least one frame profile (6, 6', 6"), characterized in that the frame profile (6, 6', 6") has a frame side (10) aligned with the battery cells (8), wherein formations (12) are formed on the frame side (10).Battery shaped frame (4) according to Claim 1, characterized in that the formations (12) are at least in sections congruent with the battery cells (8) or these at least in sections represent an enlarged contour of the battery cells (8).Battery mould frame (4) according to Claim 1 or 2, characterized in that the formations (12) are cylinder sections.Battery shaped frame (4) according to one of the preceding claims, characterized in that the formations (12) have, in plan view, a formation radius (D) which is greater than a battery cell radius (R) of the battery cells (8).Battery shaped frame (4) according to one of the preceding claims, characterized in that the formations (12) are arranged next to one another and merge into one another without edges.Battery shaped frame (4) according to one of the preceding claims, characterized in that the frame profile (6, 6', 6") is a hollow profile, wherein the formations (12) are produced by high-pressure forming.Battery shaped frame (4) according to one of the preceding claims, characterized in that the frame profile (6, 6', 6") has at least one tapered or tapered end section (18) which is connected to a further frame profile (6, 6', 6").Traction battery (2) comprising at least one battery form frame (4) according to one of the preceding claims and a plurality of battery cells (8) which are held in the battery form frame (4).Traction battery (2) according to Claim 8, characterized in that the battery cells (8) are round cells each having a battery cell radius (R), wherein the formations (12) are cylinder sections having a formation radius (D), wherein the formation radius (D) is between 0.1 mm and 15 mm greater than the battery cell radius (R).Traction battery according to Claim 8 or 9, characterized in that the battery cells (8) are adhesively bonded to the battery shaped frame (4) by means of a potting material (16).

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