Energy storage unit

Abstract

The present invention relates to an energy storage unit (10), wherein the energy storage unit (10) comprises: a battery unit (12) and an insulation unit (14), wherein the battery unit (12) is configured to store, receive, and / or release electrical energy, and the energy storage unit (10) may be placed in a limiting element (16) to apply a predetermined force to the battery unit (12), and the insulation unit (14) is placed between the battery unit (12) and the limiting element (16), and the insulation unit (14) is configured to reduce heat flow between the battery unit (12) and the limiting element (16).

Description

Technology Field

[0001] The present invention relates to an energy storage unit, a method for producing an energy storage unit, and a vehicle. Background Technology

[0002] Currently, numerous different solutions exist for configuring battery systems in the automotive sector. Driven by the mobility transition, the increasing number of battery systems and heightened performance requirements are continuously increasing the need for innovative and robust battery systems.

[0003] Continuous lightweighting in vehicle configurations to reduce consumption and increasing competition are causing cost pressures, leading to a growing demand for more affordable and efficient components for vehicles.

[0004] By embodiments of the present invention, an improved energy storage unit may be advantageously provided. The present invention is defined in independent claims. Advantageous further developments of the present invention are derived from dependent claims and the following description.

[0005] One advantage of an energy storage unit having the features of claim 1 is that the thermal conductivity of the outer surface of the battery unit can be significantly reduced by the insulating unit, so that the temperature distribution within the battery unit can be as uniform as possible. Preferably, the battery unit has a plurality of cells, wherein in particular, the cells have insulating units in contact with the frame and / or limiting element of the battery unit, so that heat flow between the battery unit having the insulating unit and adjacent non-cell components is reduced. An additional advantage is that the cells in the edge region of the battery unit preferably have insulating units, so that the internal cells of the battery unit may be substantially free of insulating units, which can have an advantageous effect on the production cost of the battery units. Preferably, the cells may be in a swollen state due to aging and / or charging, and the contact area between the battery unit and the frame element is reduced by the resulting bulging. Preferably, high mechanical rigidity of the energy storage unit can be achieved, as the limiting element in contact with the frame element can provide the necessary rigidity, while the insulating unit can block heat flow. More preferably, the insulation unit can be made particularly thin, requiring almost no additional installation space. An additional advantage is that electrical insulation between the battery unit and the limiting element or similar components can also be achieved by the insulation unit. Another advantage is that the external temperature influence on the battery unit is minimal due to the insulation unit. Furthermore, it is advantageous that thermal energy from the battery unit cannot be substantially transferred to the limiting element.

[0006] This is achieved according to the present invention, wherein an energy storage unit comprises a battery unit and an insulating unit, wherein the battery unit is configured to store, receive (charge), and / or release (discharge) electrical energy, wherein the energy storage unit may be placed on a limiting element to apply a predetermined force to the battery unit, wherein the insulating unit is placed between the battery unit and the limiting element, and wherein the insulating unit is configured to reduce heat flow between the battery unit and the limiting element.

[0007] In other words, both the heat inflow into the battery unit through the limiting element contacted by the energy storage unit and the heat outflow from the battery unit can be reduced or minimized by the insulating unit, thereby maintaining the temperature of the battery unit, particularly the individual cells of the battery unit, as uniformly as possible. Preferably, the battery unit comprises at least three electrochemical cells arranged substantially in parallel, wherein the insulating unit is preferably placed on the first and third cells. Preferably, the first and third cells may be in contact with the limiting element. Preferably, the limiting element is a housing wall or part of a module housing and / or an outer wall of the battery system. Preferably, energy storage units within vehicles are mechanically connected, for example, particularly on their sides. To ensure that the temperature within the battery unit of the energy storage unit is substantially constant, the insulating unit is preferably placed between the battery unit and the frame element or between the battery unit and the limiting element. Thus, heat flow between the battery unit and the surrounding environment of the battery unit can be reduced, and particularly minimized. For example, heat flow between the battery unit and the limiting element can be reduced, or the thermal conductivity at the limiting element is 0.1 W m⁻² -1 K -1 It can be reduced to less than

[0008] Dependent claims represent desirable further developments of the present invention.

[0009] Preferably, the battery unit has a separator layer, wherein the first elastic modulus of the separator layer is smaller than the second elastic modulus of the insulation unit.

[0010] One advantage of this embodiment is that the separator layer is softer than the insulating unit, so while the insulating unit simultaneously possesses rigidity and is very resistant to pressure, the separator layer can follow the volume change of the battery unit.

[0011] More preferably, the battery unit has an outer surface, wherein the insulating unit is disposed on the outer surface of the battery unit.

[0012] One advantage of this embodiment is that the outer surface of the energy storage unit can provide high mechanical stiffness, such as compression of < 10% at a load of 1 MPa, so the energy storage unit has increased stiffness.

[0013] More preferably, the insulating unit is placed on the battery unit by a material bonding connection.

[0014] One advantage of this embodiment is that the insulating unit can be formed separately to be connected to the battery unit. Preferably, the insulating unit can be injection molded onto the battery unit.

[0015] Preferably, the insulation unit is configured to substantially electrically insulate the battery unit from the limiting element.

[0016] One advantage is that by integrating the electrical insulation function into the insulation unit, additional components for insulation can be saved or insulation performance can be improved.

[0017] More preferably, the insulating unit forms at least one insulating structure, in particular noppen, on the battery unit.

[0018] One advantage of this embodiment is that insulating structures such as protrusions, hemispherical shapes, cylinders, truncated cones, hyperbolic surfaces, or similar structures can be applied to the battery unit by a plastic injection molding process or a similar method, so that the production cost of the energy storage unit can be further reduced.

[0019] Preferably, the insulating unit has a plurality of strands, wherein the plurality of strands form a grid structure.

[0020] One advantage of this embodiment is that the grid structure, composed of multiple strands, can exist as a semi-finished product and only needs to be cut to size, so that the grid structure can be easily fitted to the individual dimensions of the energy storage units. For example, the grid structure may be a net, an open fabric or nonwoven, a grid having a honeycomb structure, a grid having an intersecting arrangement, or something similar. In the case of fiber-based sheet materials such as fabrics, knitted fabrics, or nonwoven fabrics, it may be advantageous if the number of layers of fibers does not exceed the thickness of the limiting factor. With a larger number of layers, increased compressibility may occur.

[0021] When using materials equipped with fibers, the anisotropic properties of the fibers must be taken into account, and accordingly, the fibers must always be laid along the layer planes.

[0022] More preferably, the lattice density of the lattice structure is 10% to 50%, preferably 10% to 30%.

[0023] One advantage of this embodiment is that certain forces or fastening forces can be accommodated by a plurality of strands, while at the same time, a thermal insulation effect can be provided by the lattice structure. The strands can be designed with circular and / or elliptical profiles so that the contact area between the battery unit and the lattice structure is limited to a few narrow lines, which may imply high thermal contact resistance. If the intersections of the lattice are spatially prominent (atomic lattice model: atoms as large spheres are connected to each other by thin rods), the contact resistance between the insulation unit and the battery unit or the limiting element can be further reduced.

[0024] More preferably, a plurality of strands form a first layer and a second layer, wherein the insulating unit has a first carrier film, wherein the first carrier film is disposed between the first layer and the second layer.

[0025] One advantage of this embodiment is that the first carrier film can further reduce heat flow between the battery unit and the frame element or ambient air. In the circular or elliptical profile of the strands, there may only be point contacts between the first layer and the second layer. Additionally, it may be considered to produce two honeycomb structure layers that are not jointly overlapped (arranged apart from each other), for example, a sandwich structure of two insulating structures that contact each other only at a few intersection points.

[0026] Preferably, the insulating unit has a second carrier film and a third carrier film, wherein the second carrier film is disposed on the first side of a plurality of strands and the third carrier film is disposed on the second side of a plurality of strands.

[0027] One advantage of this embodiment is that the production process of the insulation unit can be further simplified, as a grid structure having multiple strands can be formed first and then a carrier film can be applied to both sides.

[0028] More preferably, the second carrier film is configured to form a material bonding connection with the limiting element.

[0029] One advantage of this embodiment is that the second carrier film may have an adhesive layer to secure the insulating unit to the limiting element. In particular, in this case, it may be advantageous that the insulating unit can be delivered to a production line as a complete unit and connected to the limiting element there.

[0030] Preferably, the insulation unit has at least one material selected from the group comprising: thermoplastic materials, thermosetting materials, polyphenylene sulfide, polyimide and / or polyester.

[0031] In addition, the material may include mechanical reinforcing fillers—for example, glass fibers. This allows thinner webs to be realized.

[0032] One advantage of this embodiment is that specific properties can be imparted to the insulation unit by selecting materials to suit possible usage scenarios of the energy storage unit.

[0033] More preferably, the insulation unit has at least one material selected from the group including natural building materials, wood and / or cork.

[0034] More preferably, the insulating unit has a predetermined geometric shape, wherein the predetermined geometric shape is configured to withstand a predetermined force.

[0035] One advantage of this embodiment is that fastening forces can be accommodated by the insulating unit, or the geometric shape of the insulating unit, such as a cross-section or similar, can be adjusted so that the resistance of the insulating unit corresponds to a predetermined force, thereby further reducing the required material.

[0036] Additionally, it is preferable that the insulating unit does not cover the entire surface of the battery unit and / or limiting element. Preferably, for example, are frames, wherein the frames are composed of the grid structure described above. Additionally, multilayer configurations in which the first layer and the second layer have different areas are also preferred. For example, the first layer can completely cover the surface of the cell, while the second layer covers a partial area of ​​the first layer.

[0037] A further aspect of the present invention relates to a battery system having an energy storage unit as described above and below, wherein the battery system further comprises a frame element, wherein the frame element is configured to provide at least one limiting element, wherein an insulating unit of the energy storage unit is disposed between the limiting element and the battery unit of the energy storage unit, so as to reduce heat flow between the battery unit and the limiting element.

[0038] More preferably, effective thermal management for battery systems comprising multiple cells or for battery systems may be important. To prevent individual cells within a battery system from aging at different rates, the temperature distribution between individual cells can generally be less than 4 Kelvin. Particularly for cells located outside the battery system, significantly lower temperatures may occur compared to cells inside the battery system due to heat dissipation to the surrounding environment, e.g., to the module or battery housing. Additionally, external cells are preferably more susceptible to external heat sources, such as radiation from a hot floor.

[0039] More preferably, the insulating unit is placed on the limiting element by means of a material bonding connection.

[0040] A further aspect of the present invention relates to a method for producing an energy storage unit, comprising the following steps:

[0041] - Step of providing a battery unit,

[0042] - Step of placing an insulating unit between the battery unit and the limiting element.

[0043] One advantage of this embodiment is that the energy storage unit can be configured modularly, which can increase both the production cost and adaptability of the energy storage unit.

[0044] More preferably, the placement of the insulation unit further includes the following steps:

[0045] - A step of forming an insulating structure on a battery unit to provide at least a portion of the insulating unit.

[0046] One advantage of this embodiment is that the production of the energy storage unit can be further simplified because the limiting element having an insulating structure can be formed substantially simultaneously.

[0047] A further aspect of the present invention relates to a vehicle having an energy storage unit as described above and below.

[0048] In addition, the term "unit" here should be understood broadly and includes both integrated designs of individual units and designs composed of multiple parts; it should be noted that each unit does not necessarily need to be provided in a single location within the vehicle but may be distributed throughout the entire vehicle.

[0049] All disclosures described above and below with respect to one aspect of the present invention apply equally to all additional aspects of the present invention.

[0050] Hereinafter, exemplary embodiments of the invention are described in detail with reference to the accompanying drawings. Brief explanation of the drawing

[0051] FIGS. 1 to 3f are energy storage units according to one embodiment. FIGS. 4 and 5 are flowcharts for illustrating the steps of a method according to one embodiment. FIG. 6 is a vehicle according to one embodiment. FIG. 7 is a battery system according to one embodiment. Specific details for implementing the invention

[0052] The drawings are merely schematic and not to scale. In the drawings, the same reference numerals may be provided for identical, functioning identically, or similar elements.

[0053] FIG. 1 illustrates an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes a battery unit (12) and an insulation unit (14). The battery unit (12) is preferably configured to store, receive, and / or release electrical energy, wherein the energy storage unit (10) may be placed in a limiting element (16) to apply a predetermined force to the battery unit (12), wherein the insulation unit (14) is placed between the battery unit (12) and the limiting element (16), wherein the insulation unit (14) is configured to reduce heat flow between the battery unit (12) and the limiting element (16). As can be seen in FIG. 1, the insulation unit (14) of the energy storage unit (10) is preferably in contact with the limiting element (16), particularly the limiting element (16) of the vehicle (200), so that a predetermined force (13) acts on the insulation unit (14) or the energy storage unit (10). An insulating unit (14) is preferably disposed between the battery unit (12) and the limiting element (16). As can be seen in FIG. 1, the limiting element (16) may be formed particularly on both sides of the battery unit (12), with the insulating unit (14) in contact with each limiting element (16), and the insulating units (14) in contact with the battery unit (12). More preferably, the battery unit (12) includes a separating layer (15), and the separating layer (15) may be disposed particularly between two cells of the battery unit (12).

[0054] FIG. 2a shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14). The insulating unit (14) preferably includes a plurality of strands (18) to form a grid structure.

[0055] FIG. 2b shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14) having a plurality of strands (18). As shown in FIG. 2b, the insulating unit (14) preferably has a grid structure by cross-stacking of a plurality of strands (18).

[0056] FIG. 2c shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating layer having a plurality of strands (18). The plurality of strands (18) preferably form a first layer (20) and a second layer (22), wherein a first carrier film (24) is disposed between the first layer (20) and the second layer (22).

[0057] FIG. 2d shows an energy storage unit (10) according to an embodiment. The energy storage unit (10) preferably includes a limiting element (16) on which an insulating unit (14) is disposed, and the insulating unit (14) is disposed particularly by a material bonding connection. As shown in FIG. 2d, the insulating unit (14) preferably forms an insulating structure (17) on a battery unit (12), and is formed, for example, by injection molding protrusions or similar things on the battery unit (12).

[0058] FIG. 2e shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) includes an insulating unit (14), wherein an insulating structure (17) is preferably formed on a battery unit (12). In this case, a first carrier film (24) may be disposed between the insulating structure (17) and the battery unit (12).

[0059] FIG. 2f illustrates an embodiment of an energy storage unit (10). The energy storage unit (10) preferably includes an insulating unit (14) having a plurality of strands (18). Preferably, a second carrier film (26) is disposed on the first side of the plurality of strands (18) and a third carrier film (28) is disposed on the second side of the plurality of strands (18). Preferably, the second carrier film (26) can form a material bonding connection, for example, an adhesive connection, with the battery unit (12).

[0060] FIG. 3a illustrates an embodiment of an energy storage unit (10). The energy storage unit (10) preferably includes an insulating unit (14), and the insulating unit (14) includes a plurality of strands (18) to form a grid structure, for example, having a honeycomb.

[0061] FIG. 3b shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14), and the insulating unit (14) includes a plurality of strands (18) that can form a grid structure by cross-stacking.

[0062] FIG. 3c illustrates an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14) having a plurality of strands (18). As can be seen in FIG. 3c, the plurality of strands (18) preferably form a first layer (20) and a second layer (22). More preferably, a first carrier film (24) is disposed between the first layer (20) and the second layer (22).

[0063] FIG. 3d shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14), and the insulating unit (14) may preferably be placed on a battery unit (12). In this case, the insulating unit (14) may form an insulating structure (17), and the insulating structure (17) may be, for example, protrusions or similar.

[0064] FIG. 3e shows an energy storage unit (10) according to one embodiment. The energy storage unit (10) preferably includes an insulating unit (14), and the insulating unit (14) is disposed on a first carrier film (24) applied to a battery unit (12).

[0065] FIG. 3f illustrates an embodiment of an energy storage unit (10). The energy storage unit (10) preferably includes an insulating unit (14) comprising a plurality of strands (18). Preferably, a second carrier film (26) is disposed on the first side of the plurality of strands (18) and a third carrier film (28) is disposed on the second side of the plurality of strands (18).

[0066] FIG. 4 shows a flowchart for explaining the steps of a method (100) for producing an energy storage unit (10). The method (100) preferably:

[0067] - Step (S1) of providing a battery unit (12),

[0068] - The method includes the step (S2) of placing an insulating unit (14) between the battery unit (12) and the limiting element (16).

[0069] FIG. 5 shows a flowchart for illustrating the steps of a method (100) according to one embodiment. The method (100) preferably includes the same steps S1 and S2 as already described in relation to FIG. 4. More preferably, the method (100) additionally:

[0070] - The method includes the step (S3) of forming an insulating structure (17) on the battery unit (12) to provide at least a portion of the insulating unit (14).

[0071] FIG. 6 shows a vehicle (300) according to one embodiment. The vehicle (300) preferably includes an energy storage unit (10) as described above and below.

[0072] FIG. 7 illustrates a battery system (200) according to one embodiment. The battery system (200) preferably includes an energy storage unit (10) as described above and below.

Claims

Claim 1 An energy storage unit (10) having: a battery unit (12) and an insulating unit (14), wherein the battery unit (12) is configured to store, receive, and / or release electrical energy, and the energy storage unit (10) may be placed in a limiting element (16) to apply a predetermined force to the battery unit (12), and the insulating unit (14) is placed between the battery unit (12) and the limiting element (16), and the insulating unit (14) is configured to reduce heat flow between the battery unit (12) and the limiting element (16). Claim 2 In claim 1, the battery unit (12) has a separating layer (15), and the first elastic modulus of the separating layer (15) is smaller than the second elastic modulus of the insulating unit (14), energy storage unit (10). Claim 3 In claim 1 or 2, the energy storage unit (10) is disposed on the battery unit (12) by a material bonding connection. Claim 4 In any one of claims 1 to 3, the energy storage unit (10) is configured such that the insulating unit (14) substantially electrically insulates the battery unit (12) from the limiting element (16). Claim 5 In any one of claims 1 to 4, the insulating unit (14) forms at least one insulating structure (17), particularly protrusions, on the battery unit (12), an energy storage unit (10). Claim 6 In any one of claims 1 to 5, the insulating unit (14) has a plurality of strands (18), and the plurality of strands (18) form a grid structure, an energy storage unit (10). Claim 7 An energy storage unit (10) according to claim 6, wherein the lattice density of the lattice structure is 10% to 50%, preferably 10% to 30%. Claim 8 In claim 6 or 7, the plurality of strands (18) form a first layer (20) and a second layer (22), the insulating unit (14) has a first carrier film (24), and the first carrier film (24) is disposed between the first layer (20) and the second layer (22), an energy storage unit (10). Claim 9 In claim 6 or 7, the insulating unit (14) has a second carrier film (26) and a third carrier film (28), the second carrier film (26) is disposed on the first side of the plurality of strands (18) and the third carrier film (28) is disposed on the second side of the plurality of strands (18), an energy storage unit (10). Claim 10 In any one of claims 1 to 9, the insulating unit (14) has at least one material selected from the group comprising: thermoplastic materials, thermosetting materials, polyphenylene sulfide, polyimide and / or polyester, an energy storage unit (10). Claim 11 In any one of claims 1 to 9, the insulating unit (14) is an energy storage unit (10) having at least one material selected from the group comprising natural building materials, wood and / or cork. Claim 12 A battery system (200) having an energy storage unit (10) according to any one of claims 1 to 11, wherein the battery system (200) further has a frame element (202), the frame element (202) is configured to provide at least one limiting element (16), and the insulation unit (16) of the energy storage unit (10) is disposed between the limiting element (16) and the battery unit (12) of the energy storage unit (10), so as to reduce heat flow between the battery unit (12) and the limiting element (16). Claim 13 A method (100) for producing an energy storage unit (10), comprising the steps of providing a battery unit (12) (S1) and placing an insulating unit (14) between the battery unit (12) and a limiting element (16) (S2). Claim 14 A method according to claim 13, wherein the step (S2) of placing the insulating unit (14) further comprises the step (S3) of forming an insulating structure (17) on the battery unit (12) to provide at least a portion of the insulating unit (14). Claim 15 A vehicle (300) having an energy storage unit (10) according to any one of claims 1 to 11 and / or a battery system (200) according to claim 12.

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