Storage cell arrangement, electrical energy storage and at least partially electrically powered vehicle

Abstract

A storage cell arrangement for an electrical energy storage device of a vehicle is provided, the storage cell arrangement comprising: several matrix-like arranged storage cells, a two-part frame for receiving and fixing the storage cells, the frame comprising a lower frame part with a base and side walls surrounding the base, and an upper frame part formed as a cover, which is placed on the storage cells after the storage cells have been inserted into the lower frame part, the base and cover having corresponding receptacles for receiving one storage cell each, the receptacles being formed by continuous longitudinal ribs running parallel to each other in the base and cover, which are arranged at a distance from each other.that storage cells inserted into the frame rest on the bearing surfaces of the longitudinal webs with opposing edge regions of one end face, and transverse webs running parallel to opposing second side walls of the frame and resting on the longitudinal webs, which are arranged at a distance from each other, such that storage cells inserted into the frame are held by the transverse webs on opposite sides, and - wherein the transverse webs rest on the longitudinal webs in such a way that they leave a straight and continuous path over the length of the first side walls free in a central area of ​​the longitudinal web, wherein an adhesive bead is provided on each path which mechanically connects the edge regions of the end faces with the bearing surfaces of the longitudinal webs.

Description

[0001] The invention relates to the field of electromobility and in particular to the optimization of the design of the electrical energy storage system of a vehicle that is at least partially electrically powered.

[0002] In electromobility, electrical energy storage systems are used to provide the necessary energy for electric propulsion. As is well known, an electrical energy storage system comprises several stacked storage cell assemblies, also referred to as a stack. Storage cell assemblies are formed as frames equipped with multiple storage cells. One or more storage cell assemblies are arranged in a housing and electrically connected to each other and to the outside, thus forming the electrical energy storage system. During the manufacturing of electrical energy storage systems, it is important that the storage cells are held mechanically stable within the storage cell assemblies without touching each other, and that the individual cells are cooled as effectively as possible. Weight reduction is also a goal. There is always room for improvement in these areas.

[0003] For example, GB2612085 A describes a battery module with a multitude of battery cells, where the battery cells are axially and radially fixed at their opposite ends in a cell carrier. The cell carriers for the individual cells each include grooves into which adhesive beads are applied. However, the process for applying the adhesive beads is very complex.

[0004] Therefore, one objective of the invention is to provide a method for the mechanical fastening of memory cells in a frame, which is as easy as possible to implement in process engineering.

[0005] This task is solved by the features of independent claims. Advantageous embodiments are the subject of dependent claims.

[0006] A storage cell arrangement for an electrical energy storage device of a vehicle is provided, the storage cell arrangement comprising: several matrix-like arranged storage cells, a two-part frame for receiving and fixing the storage cells, the frame comprising a lower frame part with a base and side walls surrounding the base, and an upper frame part formed as a cover, which is placed on the storage cells after the storage cells have been inserted into the lower frame part, the base and cover having corresponding receptacles for receiving one storage cell each, the receptacles being formed by continuous longitudinal ribs running parallel to each other in the base and cover, which are arranged at a distance from each other.that storage cells inserted into the frame rest on the bearing surfaces of the longitudinal webs with opposing edge regions of one end face, and transverse webs running parallel to opposing second side walls of the frame and resting on the longitudinal webs, which are arranged at a distance from each other, such that storage cells inserted into the frame are held by the transverse webs on opposite sides, and - wherein the transverse webs rest on the longitudinal webs in such a way that they leave a straight and continuous path over the length of the first side walls free in a central area of ​​the longitudinal web, wherein a bead of adhesive is provided on each path which mechanically connects the edge regions of the end faces with the bearing surfaces of the longitudinal webs.

[0007] The design of the base and lid simplifies assembly, as mechanical fastening can be achieved using an adhesive bead that can be easily applied to all layers during production. Furthermore, the minimal overlap of the storage cells' surface area by the ribs allows for improved cooling.

[0008] In one embodiment, the memory cells are designed as cylindrical cells. This is a preferred embodiment because it allows for better cooling.

[0009] In one embodiment, the crossbars of adjacent rows formed by the longitudinal bars are arranged offset from one another in such a way that the storage cells are arranged in a honeycomb configuration. This allows for a higher packing density.

[0010] In one design, the frame is rectangular, with the longer side walls being the first. The frame shape depends on the available space. Placing the bearing surfaces on the longer sides allows for material savings.

[0011] In one embodiment, the shape of the crossbars is adapted to the shape of the memory cell. This provides better support for the memory cell.

[0012] In one embodiment, the height of the crossbars is chosen such that they provide a mechanical support for the memory cell while minimally covering the cell's surface. This allows for optimized cooling.

[0013] In one embodiment, the electrical energy storage device further comprises a media-tight housing into which the frame containing the storage cells is inserted, and a cooling fluid is circulated between the storage cells. This allows for optimized cooling.

[0014] Furthermore, an electrical energy storage device is provided, comprising a media-tight housing in which at least one of the storage cell arrangements is arranged, wherein the storage cells are electrically contacted to each other and to the outside of the housing. By using the storage cell arrangement, a more efficient electrical energy storage device can be provided.

[0015] One design incorporates a coolant within the housing and between the memory cells. This allows for optimized cooling.

[0016] Furthermore, a vehicle that is at least partially electrically powered and includes an electrical energy storage system will be provided. This will result in a more efficient vehicle.

[0017] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments of the invention, with reference to the figures in the drawing, which shows details of the invention, and from the claims. The individual features can be implemented individually or in any combination in a variant of the invention.

[0018] Preferred embodiments of the invention are explained in more detail below with reference to the accompanying figures. Fig. Figure 1 shows a lower frame part of a frame for receiving memory cells of a memory cell arrangement according to an embodiment of the present invention. Fig. 2 shows the one in Fig. 1. Lower frame section shown with applied bead of glue. Fig. 3 shows the one in Fig. 2 lower frame section shown with integrated memory cells. Fig. Figure 4 shows a memory cell arrangement with a frame and memory cells inserted therein according to an embodiment of the present invention. Fig. 5 shows a sectional view AA of the in Fig. 4 memory cell arrangement shown.

[0019] In the following figure descriptions, identical elements or functions are marked with the same reference symbols.

[0020] It is known that memory cells of a memory cell array in an electrical energy storage device are fixed to mounting plates of the memory cell array. The type of fixation depends on the type of memory cell and the position of the contacts.

[0021] In Fig. Figures 1 to 5 illustrate an embodiment in which a memory cell arrangement 100 is provided with a two-part frame 1 and several memory cells 2 arranged therein in a matrix-like manner, i.e., in rows and columns, and designed as cylindrical cells. According to the invention, the memory cells 2 of the memory cell arrangement 100 are electrically contacted at their end faces 20, i.e., at their upper and / or lower surfaces. Furthermore, the memory cells 2 are axially held by the longitudinal webs 13 of the base 10 of the frame 1 described below at both end faces 20, so that they cannot move upwards or downwards (inwards). Fig. 4 and Fig. 5 in the Z-direction). However, they are also held laterally, i.e. in the X and Y directions, by the crossbars 14 of the base 10 of the frame 1 described below (round cells are thus held radially).

[0022] In Fig. Figure 1 shows the basic structure of the lower frame section of frame 1, into which the storage cells 2 are inserted during assembly. This lower frame section has a base 10 with receptacles 15 for each receiving a storage cell 2, as well as side walls 11 adjoining the outer edges of the base 10, which frame the base 10. The side walls 11 are the same height or slightly higher (in the Z-direction) than the storage cells 2. After the storage cells 2 have been inserted, an upper frame section, formed as a cover 12, is placed on top of the storage cells 2, creating a storage cell arrangement 100, as shown in Figure 1. Fig. 4 shown. This lid 12, like the base 10, has recesses 15 for each receiving a memory cell 2, and is thus formed correspondingly to the base 10, as shown in the sectional view in Fig. 5 (Cut AA from Fig. 4) can be seen. The receptacles 15 provided in base 10 and lid 12 are formed in a frame-like manner in the embodiment shown, so that the memory cells 2 contained therein can be contacted at their end faces 20.

[0023] The structure of the base 10 is described in more detail below. The base 10 consists of several parallel longitudinal ribs 13, which serve as support ribs for an edge region of the end face 20 of the storage cells 2. The lid 12 also has several parallel longitudinal ribs 13, on each of which an edge region of the other end face 20 of the storage cells 2 rests. This means that two opposing edge regions of each end face 20 of each storage cell 2 rest on adjacent longitudinal ribs 13. These thus serve as axial support surfaces 21, i.e., they prevent the storage cells 2 from moving in the axial direction (both directions), i.e., in their longitudinal direction (Z-direction). The longitudinal ribs 13 are arranged parallel to each other and parallel to opposing first side walls 11a. Advantageously, these side walls 11a are the longer side walls 11a when the frame 1 is formed as a rectangle.

[0024] The base 10 further comprises transverse webs 14, which are arranged parallel to each other and to the other two side walls 11b (which are arranged at 90 degrees to the first side walls 11a). These transverse webs 14 rest on the longitudinal webs 13 in such a way that a straight, continuous track 16 remains free in the central area of ​​the longitudinal webs 13, as shown in Fig. 2 indicated. The track 16 runs parallel to the side walls 11a, thus starting at one of the side walls 11b and ending at the opposite side wall 11b. The width of the track 16 is chosen so that a bead of adhesive 3 can be applied to it, which serves to attach the edge areas of the end faces 20 of the storage cells 2 to the bearing surfaces 21 of the longitudinal webs 13 when the storage cells 2 are inserted into the lower frame part during assembly. Fig. Figure 3 shows the assembly step after which the memory cells 2 are inserted into the lower frame part. Fig. Figure 4 shows the assembly step after the cover 12 has been placed on the memory cells 2.

[0025] The transverse webs 14 can be arranged in a line between the two side walls 11a, so that the longitudinal webs 13 and the transverse webs 14 form a grid pattern. Preferably, however, as indicated in the figures, they are arranged alternately in rows by half a distance, i.e., half the diameter of the storage cell 2, so that the recesses 15 formed by two transverse webs 14 and two longitudinal webs 13 for each storage cell 2 are arranged in a honeycomb pattern. This has the advantage that a very compact packing density is achieved, since the required distances between the storage cells 2 are achieved by the offset of the storage cells 2. This saves both weight and installation space.

[0026] The spacing between the transverse webs 14 and the spacing between the longitudinal webs 13 is chosen such that two transverse webs 14 and two longitudinal webs 13 form a receptacle 15 for a storage cell 2. The storage cell 2 rests on adjacent longitudinal webs 13 with an edge region of its end face 20 on both sides, thus holding it axially. Furthermore, two adjacent transverse webs 14 serve as a boundary or enclosure, preventing the storage cell 2 from moving laterally, i.e., in the XY plane. The transverse webs 14 advantageously have a shape that corresponds to the shape of the storage cell 2, so that its outer surface (its outline) is surrounded and mechanically held by the transverse webs 14. During the design process, care must be taken to ensure that the contact areas between the storage cell 2 and the longitudinal webs 13 and transverse webs 14 are as small as possible, while still achieving good mechanical stability.Furthermore, care must be taken to ensure that the electrical connections and the vent remain accessible and are not covered by the adhesive used to attach the edge areas of the end faces 20 of the memory cells 2 to the contact surfaces 21 of the longitudinal ribs 13. The width (in the Y-direction in the figures) of the contact surface 21 on the longitudinal rib 13 is chosen such that only an edge area of ​​the end face 20 of the memory cell 2 rests on the longitudinal rib 13. The height (in the Z-direction in the figures) of the transverse ribs 14 is chosen such that as little of the side surface (surface area for round memory cells 2) of the memory cell 2 as possible is covered by the transverse rib 14, while still providing lateral support for the memory cell 2. The minimal coverage of the outer surface of the memory cell 2 allows for improved cooling.

[0027] The crossbars 14 as well as the longitudinal bars 13 obviously also serve as spacers between two adjacent memory cells 2.

[0028] As already mentioned, the lid 12 is formed analogously to the base, i.e., it also has a track 16 provided centrally in the longitudinal webs 13, on which an adhesive bead 3 is applied. As with the base 10, the adhesive bead 3 is applied to the track 16 before assembly, so that when the lid 12 is placed on the storage cells 2 already inserted into the lower frame part, it can be bonded directly to the edge areas of the end faces 20 of these cells, e.g., by pressing the lid 12 onto the storage cells 2. Providing the adhesive bead 3 significantly simplifies assembly, since all tracks 16 of the base 10 and also of the lid 12 can be coated with the adhesive bead 3 simultaneously, and the storage cells 2 can be inserted into the lower frame part as a single unit (instead of each one individually).

[0029] The axial fixation of the storage cells 2 is achieved on both end faces 20 of the storage cells 2 at opposite areas by both the adhesive bead 3 and the longitudinal ribs 13. Lateral fixation is also achieved at two areas of the storage cell 2 that are as far apart as possible axially (just below the respective end face 20).

[0030] It is also known from the prior art to use spacer geometries to adjust the thickness of the adhesive. These serve to compensate for tolerances in the height of the memory cells 2 and are significantly thinner than the thickness of the adhesive bead 3 (e.g., by a factor of 10). Such spacer geometries can also be provided on the tracks 16 of base 10 and / or cover 12.

[0031] To manufacture the electrical energy storage device, one or more of the described storage cell arrangements 100, i.e., the frame 1 equipped with the storage cells 2, are placed in a media-tight housing (not shown) and electrically connected to each other and to the outside of the housing. If several storage cell arrangements 100 are provided, they are advantageously stacked on top of each other and placed in the housing.

[0032] Furthermore, the housing may contain a (non-electrically conductive) coolant. Due to the described design of the frame 1, this coolant can be routed between the memory cells 2. The very small coverage of the outer surface (cladding area) of the memory cells 2 by the longitudinal and transverse webs 13, 14 thus achieves optimized cooling without requiring additional installation space.

[0033] In the Fig.In the embodiments shown in Figures 1 to 5, the memory cells 2 are designed as cylindrical cells. This is the preferred embodiment. However, it is also possible to use other shapes for the memory cells 2 besides cylindrical cells, in which case the frame, in particular the crossbars 14, must be adapted to the shape of the memory cell 2.

[0034] The electrical energy storage system is used in vehicles that are at least partially electrically powered to supply energy to the electric machine (the electric drive).

Claims

[1] Storage cell arrangement (100) of an electrical energy storage device of a vehicle, wherein the storage cell arrangement (100) comprises: - several matrix-like arranged memory cells (2), - a two-part frame (1) for receiving and fixing the storage cells (2), wherein the frame (1) has a lower frame part with a base (10) and side walls (11a, 11b) surrounding the base (10), and an upper frame part formed as a cover (12), which is placed on top of the storage cells (2) after the storage cells (2) have been placed in the lower frame part, - wherein the base (10) and lid (12) each have corresponding receptacles (15) for receiving a storage cell (2), wherein the receptacles (15) are formed by continuous longitudinal webs (13) running parallel to opposite first side walls (11a) of the frame (1) in the base (10) and lid (12), which are arranged at a distance from each other such that storage cells (2) placed in the frame (1) rest with opposite edge regions of an end face (20) thereof on bearing surfaces (21) of the longitudinal webs (13), and transverse webs (14) running parallel to opposite second side walls (11b) of the frame (1) and resting on the longitudinal webs (13), which are arranged at a distance from each other such that storage cells (2) placed in the frame (1) are held on opposite sides by the transverse webs (14), and - wherein the transverse webs (14) rest on the longitudinal webs (13) in such a way that they leave a straight and continuous track (16) over the length of the first side walls (11a) in a central area of ​​the longitudinal web (13), - wherein on each track (16) a bead of adhesive (3) is provided which mechanically connects the edge areas of the end faces (20) with the bearing surfaces (21) of the longitudinal webs (13). [2] Memory cell arrangement (100) according to claim 1, wherein the memory cells (2) are formed as round cells. [3] Storage cell arrangement (100) according to claim 1 or 2, wherein transverse webs (14) of adjacent rows formed by the longitudinal webs (13) are arranged offset from each other such that the storage cells (2) are arranged in a honeycomb arrangement. [4] Memory cell arrangement (100) according to one of the preceding claims, wherein the frame (1) is rectangular and the first side walls (11a) are the longer side walls. [5] Memory cell arrangement (100) according to one of the preceding claims, wherein the shape of the crossbars (14) is adapted to the shape of the memory cell (2). [6] Memory cell arrangement (100) according to one of the preceding claims, wherein the height of the crossbars (14) is selected such that the crossbars (14) provide a mechanical support for the memory cell (2) with minimal coverage of the lateral surface of the memory cell (2). [7] Storage cell arrangement (100) according to one of the preceding claims, wherein the electrical energy storage device further comprises a media-tight housing into which the frame (1) with the storage cells (2) is inserted, and wherein a cooling liquid is guided between the storage cells (2). [8] Electrical energy storage device comprising a media-tight housing in which at least one of the storage cell arrangements (100) according to one of the preceding claims is arranged, wherein the storage cells (2) are electrically contacted to each other and to the outside of the housing. [9] Electrical energy storage device according to claim 8, wherein a cooling fluid is provided inside the housing and between the storage cells (2). [10] At least partially electrically powered vehicle comprising an electrical energy storage device according to claim 8 or 9.

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