Battery cell

Abstract

The invention relates to a battery cell (1), at least comprising: • a housing (3) which encloses a volume (2); and, arranged in the volume (2): • at least one cathode, one anode and one separator as first components (4) of a first subcell (5); • at least one cathode, one anode and one separator as second components (6) of a second subcell (7); and • at least one spacer (8) between the subcells (5, 7); wherein the first subcell (5) is adjacent to a first side wall (9) of the housing (3) and the second subcell (7) is adjacent to a second side wall (10) of the housing (3) opposite the first side wall (9), wherein an intermediate space (12) through which a gas (11) can flow is formed between the subcells (5, 7) by the spacer (8).

Description

[0001] Description

[0002] Battery cell

[0003] The invention relates to a battery cell.

[0004] A battery cell comprises a housing enclosing a volume and, arranged within that volume, at least one subcell formed by at least one cathode, one anode, and one separator. The subcell may be formed by a stack of these components. This stack, or the components themselves, may optionally be wound or coiled.

[0005] The components of the stack, i.e., the at least one cathode, the at least one anode, and the separator that distances the cathode and the anode from each other, can be arranged either stacked on top of each other or additionally wound or twisted together.

[0006] The stack can be arranged alone or together with at least one other stack in a housing to form the battery cell.

[0007] An electrolyte can, for example, be in liquid form and then be applied to the stack(s) arranged in the housing. Alternatively, an electrolyte can be in solid form and then be integrated into the stack or separator.

[0008] However, a stack does not have a housing that completely encloses the stack, but may only have retaining means that fix the shape of the stack at least temporarily (e.g. before the stack is arranged in the housing).

[0009] Accordingly, the battery cell is the smallest component with its own housing that completely encloses the volume it contains (and is designed to be liquid-tight and / or gas-tight).

[0010] A battery cell is an energy storage device used, for example, in a motor vehicle to store electrical energy. In particular, a motor vehicle has a traction drive (electric machine) to propel the vehicle, and this electric machine can be driven by the electrical energy stored in the battery cell.

[0011] A battery module comprises, in particular, a plurality of battery cells that are electrically connected in series or parallel. Individual battery modules can also be electrically connected in series or parallel.

[0012] A battery assembly comprises at least one battery module or possibly several battery modules.

[0013] A primary goal in the development of battery arrays is to ensure that all mechanical load cases can be withstood without fire or electrical short circuit. Especially with lithium-ion battery cells, mechanical damage, high temperatures, and / or excessive electrical currents can lead to thermal runaway.

[0014] During thermal runaway, the temperature of a battery cell increases continuously and sometimes exponentially due to the exothermic reactions of the battery cell's components. Temperatures of up to 1,000 °C and higher can be reached, and potentially hazardous and / or flammable gases may also be released.

[0015] The parameters influencing thermal runaway include, on the one hand, the components of the battery cell (e.g., cathode, anode, separator, electrolyte) and, on the other hand, can relate to the chemical, electrochemical, technical, and powder metallurgical properties of these components. The powder metallurgical components (electrode coatings), in particular, can contain oxygen, which can be released in large quantities during thermal runaway.

[0016] Thermal runaway must be avoided at all costs because a single such incident in just one battery cell can destroy an entire battery module, battery array, or even a vehicle containing that battery array. During thermal runaway, large quantities of gases are generated, a (liquid) electrolyte can ignite, and materials located near the battery cell can burn and / or be destroyed. Immediately prior to thermal runaway, a highly explosive and reactive mixture of various gases, such as hydrogen, carbon dioxide, carbon monoxide, ethane, methane, etc., can be generated. This mixture is surrounded by powder particles and located in a gaseous and / or liquid environment. After the gas mixture escapes from the battery cell, it reacts with any air surrounding the cell, causing the exothermic reaction to accelerate exponentially.

[0017] Such an explosive reaction can affect and damage the components surrounding the battery cell, potentially triggering a chain reaction.

[0018] The extremely hot gas generated during thermal runaway spreads within the battery cell casing. It accumulates particularly in the available spaces within the casing, especially the area between the stack of electrodes and the casing, meaning that the casing itself can be damaged by the hot gases.

[0019] Furthermore, the formation of gases initially leads to a pressure increase within the battery cell housing. This pressure increase can be reduced in a controlled manner when a certain pressure threshold is reached, using known pressure relief devices (valve, shear pin, etc.), allowing the gas to be vented from the housing. However, the pressure increase can also lead to an expansion of the volume enclosed by the housing, which can damage adjacent battery cells or other components of a battery module.

[0020] A degassing device for battery cells is known from KR 102022 0131113 A.

[0021] A degassing device for battery cells is also known from US patent 2023 / 0207953 A1.

[0022] From DE 102021 122 984 B3, a battery with a battery housing is known. Several battery cells, each with its own battery cell housing, are arranged inside the battery housing. A cooling plate is arranged on one wall of the battery housing.

[0023] The object of the present invention is to at least partially solve the problems mentioned with reference to the prior art. In particular, a battery cell is to be proposed in which the gas produced in the event of damage can be selectively discharged from the battery cell housing. Specifically, a controlled passage of the gas within the housing is to be enabled. In doing so, deformation and thermally induced damage to the housing should be prevented as far as possible.

[0024] A battery cell with the features according to claim 1 contributes to solving these problems. Advantageous further developments are the subject of the dependent claims. The features listed individually in the claims can be combined in a technologically meaningful way and can be supplemented by explanatory details from the description and / or details from the figures, thereby showing further embodiments of the invention.

[0025] A battery cell is proposed, at least comprehensively.

[0026] • a housing enclosing a volume and arranged within the volume

[0027] • at least one (first) cathode, one (first) anode and one (first) separator as the first components of a first subcell;

[0028] • at least one (second) cathode, one (second) anode, and one (second) separator as the second components of a second subcell; and

[0029] • at least one spacer between the sub-cells.

[0030] The first subcell is adjacent to a first side wall of the housing, and the second subcell is adjacent to a second side wall of the housing opposite the first. The spacer creates a gap between the subcells through which gas generated within the volume can flow.

[0031] Reference is made to the preceding statements in the introduction.

[0032] Each subcell can be formed by a stack of components. This stack, or the components themselves, can optionally be arranged in a coiled or twisted manner.

[0033] The components of the stack—that is, the at least one cathode, the at least one anode, and the separator between the cathode and the anode—can be arranged either stacked on top of each other or additionally wound or twisted together. The components can be arranged, for example, as single-sheet stacks, laminates, Z-folds, or jelly rolls, in any number. Such components and their arrangement into a stack are generally known.

[0034] The stack can be arranged alone or together with at least one other stack in a housing to form the battery cell. An electrolyte can, for example, be liquid and then circulate over the stack(s) arranged in the housing. Alternatively, an electrolyte can be solid and then integrated into the stack or the separator.

[0035] However, a stack does not have a housing that completely encloses the stack, but may only have retaining means that fix the shape of the stack at least temporarily (e.g. before the stack is arranged in the housing).

[0036] The cathode and anode (electrode) are designed in a foil-like manner, meaning they have a large surface area and a small thickness. A coating of active material is applied to the surface, or each surface, of the electrode. The separator is positioned between the surfaces of adjacent, different electrodes. Uncoated portions of the electrodes extend from the stack to act as conductors.

[0037] In particular, the anodes and cathodes within the stack of a subcell are connected in parallel, so that the current collectors of a plurality of anodes are electrically connected to each other and the current collectors of a plurality of cathodes are electrically connected to each other. The current collectors of the subcells are then connected to at least one contact.

[0038] The battery cell is in particular a lithium-containing battery cell, especially a secondary cell, i.e. a rechargeable battery cell.

[0039] Accordingly, the battery cell is the smallest component with its own housing that completely encloses the volume it contains (and is designed to be liquid-tight and / or gas-tight).

[0040] The subcells can be connected to each other, in particular via at least one of their components. For example, at least one component of one subcell can simultaneously form a component of the other subcell. For example, the components can extend around the spacer, i.e., be wound around it.

[0041] Preferably, the subcells are designed independently of one another, so that the individual components of each subcell are assigned to only one subcell. The spacer creates a gap between the subcells through which gas generated within the volume can flow. Gas generated within the volume, e.g., from the components, can thus enter the space formed by this gap. In particular, this prevents the gas from flowing along the first or second side wall, i.e., between the respective subcell and the respective side wall of the housing.

[0042] The gas is only formed in the event of damage to the battery cell, for example, in the case of thermal runaway. The gas then forms in at least one of the components of the sub-cell, causing the pressure within the entire volume of the casing to increase.

[0043] In conventional battery cells, the gas spreads evenly within the casing and, in particular, comes into contact with the casing's side walls. This can lead to damage to the side walls from the hot gas. The spacer proposed here allows the hot gas to be directed into the space between the cells and a pressure relief device located on the casing. This prevents damage to the side walls.

[0044] In particular, the housing features a pressure relief device through which any overpressure within the volume, when a limit value (the pressure) is exceeded, can be released to the surrounding environment of the battery cell. The at least one spacer creates a flow path for the gas between the sub-cells and towards the pressure relief device.

[0045] The pressure relief device comprises, for example, a valve or a predetermined breaking point in the housing, such as a diaphragm. Such pressure relief devices for battery cells are known. The pressure limit at which the pressure relief device establishes a fluid connection between the volume and the environment is, in particular, between 0.2 and 1.0 bar, preferably between 0.4 and 0.8 bar (as the pressure difference between the pressure inside the volume and the environment).

[0046] In particular, at least one, and possibly several, pressure relief devices are provided on the battery cell housing. The spacer forms, in particular, one or more flow paths within the space between the cells, which guide the gas generated from the edges of the respective sub-cell towards the at least one pressure relief device.

[0047] In particular, the gas generated within the volume of the battery cell in the event of damage (i.e., in a non-operational state) is at least partially directed away from the side walls and into the space between the cells, and then specifically directed through this space to the at least one pressure relief device. Specifically, the space between the cells provides an area into which the generated gas can spread. This prevents the gas from accumulating between the individual cells and the side walls of the housing, which could potentially deform or thermally damage the housing.

[0048] Structures formed by the spacer are provided in the intermediate space to guide the gas. These structures include, for example, internal components, embossings, or other types of flow resistance that direct the gas from the edges of the intermediate space or the sub-cells towards the at least one pressure relief device.

[0049] In particular, the housing has side walls oriented differently from one another and at least one electrical contact, wherein an electrical connection of the subcells to a circuit located outside the housing can be established or is established via the electrical contact. The pressure relief device is located, in particular, on a third side wall and the at least one electrical contact on another fourth side wall.

[0050] The housing is constructed in a known manner, specifically having at least one electrical contact (pole) through which an electrical connection between the subcells and a circuit located outside the housing can be established or is established. In particular, the housing has two electrical contacts, or possibly more than two. The second electrical contact can also be formed by the housing itself. However, a second electrical contact is specifically provided. This can be located on the same side wall as the first electrical contact or on a different, particularly opposite, side wall.

[0051] It is of course also possible to arrange the pressure relief device and the electrical contact on the same side wall. However, arranging them on different side walls allows the hot gas to be vented to the environment via the pressure relief device without damaging the electrical circuit or other components.

[0052] In particular, the housing is (essentially) cuboid in shape and has six side walls (chamfers on the housing or similar features are specifically disregarded). Specifically, the third side wall (and the fifth side wall) has a smaller area than the first and second side walls, and the fourth and sixth side walls have a smaller area than the third side wall.

[0053] In particular, each electrical contact is located on the fourth (or sixth) side wall.

[0054] In particular, each pressure relief device is located on the third (or fifth) side wall.

[0055] In particular, the first and second side walls form the largest side walls of the battery cell in terms of surface area.

[0056] In particular, the first subcell is arranged directly adjacent to the first side wall, and the second subcell is arranged directly adjacent to the second side wall. "Directly adjacent" means, in particular, that the subcell is in contact with the corresponding side wall, so that there is just no gap between the side wall and the subcell into which the gas could spread.

[0057] In particular, the casing is rigid and only plastically deformable, while the individual cells are casing-free. A rigid casing is generally referred to as a hard case, and the battery cell is then called a prismatic battery cell, in contrast to a so-called pouch cell, where the casing is formed by a pouch film.

[0058] A pouch cell comprises a deformable housing made of a pouch film and is therefore not a prismatic cell (with a rigid housing). A pouch film is a known deformable housing component used as a housing for so-called pouch cells. It is a composite material, for example, comprising a plastic and aluminum. In particular, the housing is made of a metallic material, wherein the metallic material, unlike a thin film, has a thickness of at least 0.3 millimeters, preferably at least 0.5 millimeters, and most preferably at least 0.7 millimeters.

[0059] The housing can also be designed as a pouch cell or made from a pouch film, however, the possible deformation caused by the gas produced is difficult to avoid.

[0060] Housing-free means, in particular, that the subcell consists only of the components anode, cathode, separator, and, if applicable, electrolyte. A retaining element may be provided to fix the shape of the component stack, at least temporarily (e.g., before the stack is placed in the housing), but not a housing that completely encloses the stack (and is liquid-tight or gas-tight from the environment).

[0061] In particular, the at least one spacer comprises at least one plate extending in a plane parallel to the subcells and featuring a plurality of embossings extending transversely to this plane, the embossings forming the space between the plates. The embossings can be, for example, point-shaped, circular, or elongated. The embossings form raised areas on one side of the plate and depressions on the other. Optionally, a second plate can be completely flat or also provided with embossings. The embossings of the two plates can contact each other, thus creating a larger space between the plates, or be arranged side by side, for example, to form a flow path.

[0062] The plates ensure, in particular, that the sub-cells do not transmit locally increased compressive forces (e.g., via the point-like indentations) to each other. The plates can distribute the resulting compressive forces over a large area, so that the sub-cells are subjected to a uniform compressive force across the surface where the spacer is located.

[0063] In particular, the spacer extends over the entire surface of the subcell facing the other subcell.

[0064] The spacer can be made of, for example, a plastic material, a ceramic material, an organic or inorganic composite material, or a metallic material. In particular, the spacer should withstand the temperature stress caused by the hot gas in order to maintain the gap and, especially, the flow path to the pressure relief device, at least for a certain period of time.

[0065] In particular, the spacer comprises an extruded profile, with flow paths for the gas being provided via the cavities of the extruded profile.

[0066] In particular, the at least one spacer comprises a first plate and a second plate, each extending in a plane parallel to the subcells, the plates being spaced apart from each other by at least one spacer element and thus forming the gap. The spacer element can be connected to at least one of the plates (or possibly both plates), in particular by a material bond.

[0067] The at least one spacer element has, in particular, a corrugated structure (e.g., like a corrugated sheet) or extends essentially transversely to the plane through the gap (e.g., like a wall). The spacer element itself can, for example, be...

[0068] have openings or penetrations so that the resulting gas can also flow through the spacer elements.

[0069] In particular, the spacer forms a thermally conductive connection with at least one side wall, preferably at least with the third and fifth, or alternatively or additionally with the fourth and sixth side wall, for the purpose of dissipating heat from the volume to the side wall.

[0070] Especially in the case of a prismatic battery cell with a dimensionally stable housing, the spacer can, for example, be materially bonded to at least one side wall, whereby this materially bonded connection forms a particularly suitable thermally conductive connection, especially in the case of metallic materials.

[0071] A battery arrangement is proposed, comprising at least a plurality of battery cells electrically connected in series or parallel.

[0072] A motor vehicle is further proposed, comprising at least a traction unit for propelling the motor vehicle and the described battery cell or battery arrangement for storing a predetermined or required amount of energy for propelling the traction unit. The descriptions of the battery cell are particularly applicable to the battery arrangement and the motor vehicle, and vice versa.

[0073] The use of indefinite articles (“a”, “an”, “one”, and “ones”), particularly in the patent claims and the description reproducing them, is to be understood as such and not as a numeral. Accordingly, terms or components introduced by these articles are to be understood as occurring at least once and, in particular, may also occur multiple times.

[0074] It should be noted as a precaution that the numerical terms used here ("first", "second", etc.) primarily serve (only) to distinguish between several similar objects, quantities, or processes, and thus do not necessarily dictate any dependency and / or sequence between these objects, quantities, or processes. Should a dependency and / or sequence be required, this is explicitly stated here, or it will be obvious to a person skilled in the art upon studying the specific configuration described. Where a component can occur multiple times ("at least one"), the description for one of these components may apply equally to all or some of the multiple components, but this is not mandatory.

[0075] The invention and its technical context are explained in more detail below with reference to the accompanying figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the situations described in the figures and combine them with other components and findings from the present description. It should be emphasized that the figures, and especially the depicted dimensions, are only schematic. They show:

[0076] Fig. 1: a battery cell in a perspective view;

[0077] Fig. 2: a known battery cell in a side view in section;

[0078] Fig. 3: the battery cell according to Fig. 2 in a different side view in section;

[0079] Fig. 4: the battery cell according to Fig. 1 in a side view in section; Fig. 5: the battery cell according to Fig. 4 in a perspective view;

[0080] Fig. 6: a first embodiment of a spacer in a side view;

[0081] Fig. 7: the spacer according to Fig. 6 in a different side view;

[0082] Fig. 8: a spacer element of a spacer in a perspective view;

[0083] Fig. 9: a second embodiment of a spacer with a spacer element according to Fig. 8;

[0084] Fig. 10: a third embodiment of a spacer in a side view;

[0085] Fig. 11: the spacer according to Fig. 10 in a different side view;

[0086] Fig. 12: a fourth embodiment of a spacer in a side view;

[0087] Fig. 13: the spacer according to Fig. 12 in another side view; and

[0088] Fig. 14: a fifth embodiment of a spacer in a perspective view

[0089] Opinion.

[0090] Fig. 1 shows a battery cell 1 in a perspective view. The battery cell 1 comprises a housing 3 enclosing a volume 2 and two subcells 5, 7 arranged in the volume 2.

[0091] The housing 3 has two electrical contacts 20, via which an electrical connection between the subcells 5, 7 and a circuit 21 located outside the housing 3 can be established or is established. The contacts 20 are arranged on opposite side walls 17, 19.

[0092] The housing 3 has a pressure relief device 13, through which any overpressure existing in the volume 2 can be released to the surrounding environment 14 of the battery cell 1 when a limit value (of the pressure) is exceeded. The housing 3 has side walls 9, 10, 16, 17, 18, 19 oriented differently from one another. The housing 3 is cuboid in shape and has six side walls 9, 10, 16, 17, 18, 19. The third side wall 16 and the fifth side wall 18 have a smaller area than the first side wall 9 and the second side wall 10, and the fourth side wall 17 and the sixth side wall 19 have a smaller area than the third side wall 16 and the fifth side wall 18. The pressure relief device 13 is located on the third side wall 16, and the electrical contacts 20 are located on the fourth side wall 17 and the sixth side wall 19.

[0093] The housing 3 is dimensionally stable and only plastically deformable, with the subcells 5, 7 (see Fig. 2 to 4) being housing-free.

[0094] Fig. 2 shows a known battery cell 1 in a side view in section. Fig. 3 shows the battery cell 1 from Fig. 2 in another side view in section. Figs. 2 and 3 are described together below. Reference is made to the description of Fig. 1.

[0095] The battery cell 1 comprises a housing 3 enclosing a volume 2 and a first subcell 5 arranged within the volume 2. The first subcell 5 is formed by at least one cathode, one anode, and one separator (components 4) stacked on top of each other. An electrolyte can, for example, be liquid and thus present in the stack arranged within the housing 3. Alternatively, an electrolyte can be solid and thus integrated within the stack or the separator.

[0096] However, the subcell 5, 7 or the stack itself does not have a housing 3 that completely encloses the stack, but possibly only retaining means that fix the shape of the stack at least temporarily (e.g. before the stack or the subcell 5 is arranged in the housing 3).

[0097] Accordingly, the battery cell 1 is the smallest component with its own housing 3, which completely encloses the volume 2 it contains (and is designed to be liquid-tight and / or gas-tight).

[0098] During thermal runaway, the temperature of a battery cell 1 increases continuously and partially exponentially due to the exothermic reactions of components 4, 6 of the battery cell 1. Temperatures of up to 1,000 °C [degree Celsius] and higher can be reached, and potentially hazardous and / or flammable gases 11 may also be released.

[0099] During thermal runaway, large quantities of gases 11 are generated. Immediately prior to thermal runaway, a highly explosive and reactive mixture of various gases 11 can be generated, e.g., comprising hydrogen, carbon dioxide, carbon monoxide, ethane, methane, etc., surrounded by powder particles and arranged in a gaseous and / or liquid environment. After the gas mixture breaks through the battery cell 1, it reacts with the ambient air 14 that may be surrounding the battery cell 1, causing the exothermic reaction to accelerate exponentially.

[0100] Such an explosive reaction can affect and damage the components 4, 6 surrounding battery cell 1, potentially triggering a chain reaction.

[0101] The very hot gas 11 generated during thermal runaway spreads within the housing 3 of the battery cell 1 as shown (see arrows). The gas 11 settles particularly in the available spaces within the housing 3. These spaces include, in particular, the area between the stack of components 4, 6 and the housing 4 (gap 30), so that the housing 3 is especially vulnerable to damage from the hot gases 11.

[0102] Furthermore, the formation of gases 11 leads to a pressure increase in the housing 3 of the battery cell 1. This pressure increase can be reduced in a controlled manner via a pressure relief device 13 when a pressure limit is reached, and the gas 11 can be directed out of the housing 3. However, the pressure increase can also lead to an increase in the volume 2 enclosed by the housing 3 (see Fig. 3), which can damage adjacent battery cells 1 or other components 4, 6 of a battery module.

[0103] Fig. 4 shows the battery cell 1 according to Fig. 1 in a side view in section. Fig. 5 shows the battery cell 1 according to Fig. 4 in a perspective view. Figs. 4 and 5 are described together below. Reference is made to the descriptions of Figs. 1 to 3.

[0104] The battery cell 1 comprises a first subcell 5 with at least one cathode, one anode, and one separator as first components 4, and a second subcell 7 with at least one cathode, one anode, and one separator as second components 6. The battery cell further comprises at least one spacer 8 between the subcells 5 and 7. The first subcell 5 is arranged directly adjacent to a first side wall 9 of the housing 3, and the second subcell 7 is arranged directly adjacent to a second side wall 10 of the housing 3, opposite the first side wall 9. The spacers 8 form a space 12 between the subcells 5 and 7, through which a gas 11 generated within the volume 2 can flow.

[0105] The spacers 8 form a flow path 15 for the gas 11 between the subcells 5, 7 and towards the pressure relief device 13. The spacers 8 thus form one or more flow paths 15 within the space 12, which guide the gas 11 from the edges of the respective subcells 5, 7 towards the at least one pressure relief device 13.

[0106] The gas 11 that arises within volume 2 in the event of damage (i.e., in a non-operational state) of battery cell 1 is at least partially removed by the side walls.

[0107] 9, 10, 16, 17, 18, 19 away from and towards the space 12 and via the space 12 specifically towards the at least one pressure relief device 13. The space 12 provides an area in which the resulting gas 11 can spread. This prevents the gas 11 from spreading between the sub-cells 5, 7 and the side walls 9,

[0108] 10, 16, 17, 18, 19 of the housing 3 and may deform or thermally damage it.

[0109] Structures formed by the at least one spacer 8 can be provided in the space 12 to guide the gas 11. These structures include, for example, internal components, embossings 25, or other types of flow resistances that guide the gas 11 from the edges of the space 12 or the sub-cells 5, 7 towards the at least one pressure relief device 13.

[0110] Fig. 6 shows a first embodiment of a spacer 8 in a side view. Fig. 7 shows the spacer 8 according to Fig. 6 in another side view. Figs. 6 and 7 are described together below. Reference is made to the descriptions of Figs. 1 to 5.

[0111] The spacer 8 comprises a first plate 22 and a second plate 23, each extending in a plane 24 parallel to the subcells 5, 7. Each plate 22, 23 has a plurality of indentations 25 extending transversely to the plane 24, the indentations 25 forming the space 12. The indentations 25 are point-shaped or circular. The indentations 25 form raised areas on one side of the plate 22, 23 and depressions on the other side. The indentations 25 of the two plates 22, 23 are arranged side by side and thus serve to form a flow path 15.

[0112] The plates 22, 23 ensure that the subcells 5, 7 do not transmit locally increased compressive forces (e.g., via the point-shaped indentations 25) to each other. The plates 22, 23 can distribute the resulting compressive forces over a large area, so that the subcells 5, 7 are subjected to a uniform compressive force across the area where the spacer 8 is located.

[0113] The spacer 8 extends over the entire surface of each subcell 5, 7 facing the other subcell 7, 5.

[0114] Fig. 8 shows a distance element 26 of a spacer 8 in a perspective view.

[0115] Fig. 9 shows a second embodiment of a spacer 8 with a spacer element 26 according to Fig. 8. Figs. 8 and 9 are described together below. Reference is made to the descriptions of Figs. 1 to 7.

[0116] The spacer 8 comprises a first plate 22 and a second plate 23, each extending in a plane 24 arranged parallel to the subcells 5, 7, the plates 22, 23 being spaced apart from each other by a spacer element 26 and thus forming the space 12. The spacer element 26 can be materially bonded to at least one of the plates 22, 23 (or optionally both plates 22, 23).

[0117] The spacer element 26 has a corrugated structure 27 (e.g., similar to a corrugated sheet). The spacer element 26 itself has openings 29, allowing the resulting gas 11 to flow through the spacer element 6. The flow paths 15 can run along the corrugated structure 27 (i.e., along the channels formed by the corrugated structure 27) or perpendicular to it through the openings 29.

[0118] The spacer element 26 can also be used without the plates 22, 23 as a spacer 8.

[0119] Fig. 10 shows a third embodiment of a spacer 8 in a side view.

[0120] Fig. 11 shows the spacer 8 from Fig. 10 in a different side view. Figs. 10 and 11 are described together below. Reference is made to the descriptions of Figs. 1 to 9. The spacer 8 comprises a first plate 22 and a second plate 23, each extending in a plane 24 arranged parallel to the subcells 5, 7, the plates 22, 23 being spaced apart from each other by spacer elements 26 and thus forming the space 12. The spacer elements 26 are formed by elongated structures that are arranged on at least one plate 22, 23 and thus form a plurality of flow paths 15 towards the pressure relief device 13.

[0121] The spacer 8 forms at least a thermally conductive connection 28 with the third side wall 16, on which the pressure relief device 13 is arranged, for the removal of heat from the volume 2 towards the third side wall 16 and thus towards the environment 14.

[0122] In the case of the prismatic battery cell 1 with the dimensionally stable housing 3, it is particularly advantageous if the spacer 8 is materially bonded to the third side wall 16, whereby this materially bonded connection 28 forms a particularly suitable thermally conductive connection 28, especially in the case of metallic materials (of spacer 8 and third side wall 16).

[0123] Fig. 12 shows a fourth embodiment of a spacer 8 in a side view.

[0124] Fig. 13 shows the spacer 8 from Fig. 12 in a different side view. Figs. 12 and 13 are described together below. Reference is made to the descriptions of Figs. 1 to 11.

[0125] The spacer 8 comprises a first plate 22 and a second plate 23, each extending in a plane 24 parallel to the subcells 5, 7, the plates 22, 23 being spaced apart from each other by spacer elements 26 and thus forming the space 12. The spacer elements 26 extend essentially transversely to the plane 24 through the space 12, like a wall. Here too, the spacer elements 26 can have openings 29, so that the resulting gas 11 can be guided through the spacer elements 6 along deliberately formed flow paths 15.

[0126] Fig. 14 shows a fifth embodiment of a spacer 8 in a perspective view. Reference is made to the descriptions in Figs. 1 to 13. Here, the spacer 8 is designed as an extruded profile, with flow paths 15 for the gas 11 provided via the cavities of the extruded profile.

[0127] Reference symbol list

[0128] Battery cell

[0129] volume

[0130] Housing first component first sub-cell second component second sub-cell spacer first side wall second side wall

[0131] gas

[0132] space

[0133] Pressure relief device, surroundings, flow path, third side wall, fourth side wall, fifth side wall, sixth side wall, contact

[0134] Circuit first plate second plate

[0135] level

[0136] embossing

[0137] Spacer

[0138] Well structure

[0139] Connection Opening Gap

Claims

Patent claims 1. Battery cell (1), at least comprising • a housing (3) enclosing a volume (2) and arranged in the volume (2) • at least a cathode, an anode and a separator as first components (4) of a first subcell (5); • at least a cathode, an anode and a separator as the second components (6) of a second subcell (7); and • at least one spacer (8) between the subcells (5, 7); wherein the first subcell (5) is adjacent to a first side wall (9) of the housing (3) and the second subcell (7) is adjacent to a second side wall (10) of the housing (3) opposite the first side wall (9), wherein the spacer (8) forms an intermediate space (12) between the subcells (5, 7) through which a gas (11) formed within the volume (2) can flow.

2. Battery cell (1) according to claim 1, wherein the housing (3) has a pressure relief device (13) via which an overpressure existing in the volume (2) can be released to an environment (14) of the battery cell (1) when a limit value is exceeded; wherein a flow path (15) for the gas (11) is formed by the at least one spacer (8) between the subcells (5, 7) and towards the pressure relief device (13).

3. Battery cell (1) according to claim 2, wherein in the event of damage to the battery cell (1) the gas (11) arising within the volume (2) can be directed at least partially away from the side walls (9, 10, 16, 17, 18, 19) and towards the space (12) and via the space (12) specifically towards the pressure relief device (13).

4. Battery cell (1) according to one of the preceding claims 2 and 3, wherein the housing (3) has differently oriented side walls (9, 10, 16, 17, 18, 19) and at least one electrical contact (20), wherein an electrical connection of the subcells (5, 7) to a circuit (21) arranged outside the housing (3) can be established via the electrical contact (20); wherein the pressure relief device (13) on a third side wall (16) and at least one electrical contact is arranged on another fourth side wall (17).

5. Battery cell (1) according to one of the preceding claims, wherein the housing (3) is cuboid in shape and has six side walls (9, 10, 16, 17, 18, 19), wherein the first subcell (5) is arranged directly adjacent to the first side wall (9) and the second subcell (7) is arranged directly adjacent to the second side wall (10), wherein the first side wall (9) and the second side wall (10) are the side walls (9, 10) of the housing (3) with the largest surface area.

6. Battery cell (1) according to one of the preceding claims, wherein the housing (3) is dimensionally stable and only plastically deformable and the sub-cells (5, 7) are designed without a housing.

7. Battery cell (1) according to one of the preceding claims, wherein the at least one spacer (8) comprises at least one plate (22, 23) which extends in a plane (24) arranged parallel to the subcells (5, 7) and has a plurality of embossings (25) extending transversely to the plane, wherein the embossings (25) form the space (12).

8. Battery cell (1) according to one of the preceding claims, wherein the at least one spacer (8) comprises a first plate (22) and a second plate (23) which each extend in a plane (24) arranged parallel to the subcells (5, 7), wherein the plates (22, 23) are spaced apart from each other over at least one spacer element (26) and thus form the space (12).

9. Battery cell (1) according to claim 8, wherein the at least one spacer element (26) has a wave structure (27) or extends substantially transversely to the plane (24) through the space (12).

10. Battery cell (1) according to one of the preceding claims, wherein the spacer (8) with at least one side wall (9, 10, 16, 17, 18, 19) forms a thermally conductive connection (28) for the removal of heat from the volume (2) towards the side wall (9, 10, 16, 17, 18, 19).

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