Traction battery for a vehicle

Abstract

The present disclosure relates to a traction battery (100) for a vehicle (10), comprising: - several battery cells; and - a first cooling arrangement (110) for the multiple battery cells, wherein the first cooling arrangement (110) is arranged adjacent to the multiple battery cells and comprises multiple cooling levels (112) for a first coolant, wherein the first cooling arrangement (110) comprises at least one first inlet (114A) and at least one first outlet (116A) at a first end region of the multiple cooling levels (112) as well as at least one second inlet (114B) and at least one second outlet (116B) at a second end region of the multiple cooling levels (112), such that at least one first cooling level of the multiple cooling levels (112) is supplied with coolant in a first flow direction (SR1) and at least one second cooling level of the multiple cooling levels (112) is supplied with coolant in a second flow direction (SR2) opposite to the first flow direction (SR1).

Description

[0001] The present disclosure relates to a traction battery for a vehicle and a vehicle with such a traction battery. The present disclosure relates in particular to an alternating flow concept for a heat exchanger or a radiator with a double-sided inlet and return for a coolant. State of the art

[0002] A high-voltage battery in a hybrid or electric vehicle is an energy storage system that stores electrical energy in the form of high-voltage direct current. This stored energy is used to power at least one of the vehicle's electric motors. Typically, these high-voltage batteries are composed of lithium-ion storage cells or modules configured in a battery pack.

[0003] During operation, such high-voltage storage systems often require temperature control (i.e., cooling and / or heating) to ensure battery performance and lifespan. It is crucial that heat dissipation and heat input occur as uniformly as possible across the entire surface of the high-voltage storage system. However, with a uniform flow direction in all cooling loops, an undesirable temperature gradient can develop along the flow direction. This temperature gradient can amount to several Kelvin in long cooling loops, depending on the volumetric flow rate. One solution to this problem is the so-called U-flow with inflection points, which reduces the temperature gradient. However, this method is difficult to implement due to limited installation space, especially with low z-dimensions of the system.The U-flow requires a stacked inlet and outlet, which in such compact systems can lead to increased pressure losses that negatively affect the overall system. Disclosure of the invention

[0004] It is an objective of the present disclosure to specify a traction battery for a vehicle and a vehicle with such a traction battery, which enables efficient cooling of the battery cells. Furthermore, it is an objective of the present disclosure to improve the performance and service life of the traction battery.

[0005] This problem is solved by the subject matter of the independent claims. Advantageous embodiments are specified in the dependent claims.

[0006] According to an independent aspect of the present disclosure, a traction battery for a vehicle, in particular a motor vehicle, is specified. The traction battery comprises several battery cells; and a first cooling arrangement for the several battery cells, wherein the first cooling arrangement is arranged adjacent to the several battery cells (e.g. below and / or above and / or beside and / or in front of and / or behind the several battery cells) and comprises several cooling levels for a first coolant (orwith a first coolant) comprising, wherein the first cooling arrangement comprises at least a first inlet and at least a first outlet at a first end region of the multiple cooling levels, as well as at least a second inlet and at least a second outlet at a second end region of the multiple cooling levels, such that at least one first cooling level of the multiple cooling levels is traversed by the first coolant in a first flow direction, and at least one second cooling level of the multiple cooling levels is traversed by the first coolant in a second flow direction opposite to the first flow direction.

[0007] According to the invention, at least one inlet and one outlet are arranged on opposite sides of the cooling levels, allowing flow to pass through the cooling levels in opposite directions without any turning points. In other words, there is no U-flow with turning points, yet the temperature gradient can still be reduced, resulting in uniform temperature control across the entire surface of the traction battery. Furthermore, pressure losses, such as those occurring in a U-flow or in an alternating flow (I-flow), can be reduced. Consequently, the efficiency of the temperature control mechanism can be improved, which in turn ensures the performance and service life of the traction battery. Additionally, the diameter of the inlet and outlet lines can be smaller due to the doubling of the arrangement on both sides, thus allowing for better utilization of installation space, particularly with small z-dimensions.

[0008] Although the present disclosure refers to “cooling levels” and “coolant”, it should be understood that the coolant flowing through the cooling levels can also provide heating for the battery cells, e.g. at low outside temperatures.

[0009] A traction battery for a vehicle, also called a drive battery or high-voltage storage device, generally consists of a large number of individual cells connected together to provide the total energy and voltage required for the electric drive. These battery cells can be, for example, rechargeable lithium-ion cells, but the present disclosure is not limited to this.

[0010] Preferably, the battery cells are configured in one or more battery modules. A battery module is an assembly consisting of a plurality of interconnected battery cells. Each cell in a module is an independent unit that stores and releases electrical energy. The cells are joined together in a specific arrangement (series, parallel, or a combination of both) to achieve a higher overall voltage, capacity, and power than a single cell could provide. However, the present disclosure is not limited to this, and in other embodiments, for example, a cell-to-pack approach is conceivable, in which the individual battery cells are integrated directly into the storage housing without being configured in battery modules.

[0011] The first cooling arrangement is located adjacent to, specifically below and / or above, the multiple battery cells. The terms "below" and "above" refer to the vertical orientation and / or height of the traction battery, particularly when it is installed in the vehicle. This means that the first cooling arrangement can be positioned either below or above the battery cells, or in both positions, with the vertical positioning being relevant in relation to the overall height of the traction battery. This arrangement ensures optimal cooling of the battery cells, especially in the confined space of a vehicle.

[0012] The first flow direction corresponds to, or is parallel to, a first direction. The second flow direction corresponds to, or is parallel to, the first direction and opposite to the first flow direction. For example, the first direction may be an x-direction, particularly in a top view of the propulsion battery. In this case, the first flow direction may be a positive x-direction, and the second flow direction may be a negative x-direction. Alternatively, the first flow direction may be a negative x-direction, and the second flow direction may be a positive x-direction.

[0013] Preferably, the multiple battery cells are arranged essentially parallel to each other, in particular above and / or below the first cooling arrangement.

[0014] Preferably, the multiple cooling levels are arranged essentially parallel to each other.

[0015] Preferably, the multiple cooling levels are plate-shaped and / or planar. A plate-shaped cooling level has the form of a plate, meaning that the cooling level has a comparatively small thickness in relation to its length and width (or height).

[0016] In some embodiments, the thickness of a cooling plane can be defined in the second direction, which is essentially perpendicular to the first and / or second flow direction. For example, the second direction can be perpendicular to the x-direction and can be, for instance, the y-direction, particularly in a top view of the traction battery. The length of a cooling plane can be defined in the first direction. The height of a cooling plane can be defined in the third direction, which is perpendicular to the first and second directions and can be, for example, the z-direction.

[0017] Preferably, the first cooling layer is alternately traversed by the first coolant in the first flow direction and the second flow direction. In particular, adjacent cooling layers can be traversed in opposite flow directions. For example, a first cooling layer can be traversed in the first flow direction, a second cooling layer can be traversed in the second flow direction, a third cooling layer can be traversed in the first flow direction, a fourth cooling layer can be traversed in the second flow direction, and so on.

[0018] Preferably, the first flow direction and the second flow direction lie in the same plane. This plane can, for example, be an xy-plane.

[0019] Preferably, the at least one first inlet and the at least one first outlet are arranged essentially perpendicular to the plane (e.g. in the z-direction) one above the other and / or the at least one second inlet and the at least one second outlet are arranged essentially perpendicular to the plane (e.g. in the z-direction) one above the other.

[0020] Alternatively, the at least one first inlet and the at least one first outlet can be arranged next to each other in the plane (e.g. in the x or y direction) and / or the at least one second inlet and the at least one second outlet can be arranged next to each other in the plane (e.g. in the x or y direction).

[0021] Preferably, the traction battery further comprises a second cooling arrangement, which is provided for a second coolant that flows around the plurality of battery cells.

[0022] Preferably, a (third) flow direction of the second coolant is substantially perpendicular to the first flow direction and / or substantially perpendicular to the second flow direction of the first coolant. For example, the (third) flow direction of the second coolant can be substantially parallel to the third direction, such as the z-direction, and can in particular be a vertical flow direction.

[0023] Preferably, the second cooling arrangement is configured for direct immersion temperature control (e.g., immersion cooling) of battery cells. Direct immersion temperature control of battery cells is a temperature control technique in which the battery cells are completely immersed in a medium to transfer heat directly and efficiently.

[0024] Preferably, the second coolant is a dielectric. Typical dielectric fluids include special cooling oils, fluorocarbons, esters, or other insulating fluids.

[0025] Preferably, the first cooling arrangement is configured to temper, and in particular cool, the second coolant of the second cooling arrangement. In other words, the first cooling arrangement can serve as a heat exchanger for the second coolant.

[0026] Preferably, several heat exchanger sections of the second cooling arrangement are arranged between the cooling levels of the first cooling arrangement, so that the second coolant can be tempered by the first cooling arrangement.

[0027] Preferably, the multiple heat exchanger sections comprise fins that are surrounded by the second coolant, which comes from the battery cells. This increases the efficiency of the heat exchange.

[0028] Preferably, the multiple heat exchanger sections and the multiple cooling levels are arranged alternately. In particular, each heat exchanger section can be arranged between two adjacent cooling levels or be enclosed on both sides by the adjacent cooling levels.

[0029] Preferably, the multiple heat exchanger sections and the multiple cooling levels are arranged alternately along the second direction, such as the y-direction.

[0030] Preferably, each battery cell module and / or the drive energy storage system, such as a high-voltage storage system, comprises a plurality of battery cells.

[0031] Preferably, the multitude of battery cells are cylindrical cells. However, the present disclosure is not limited to this and the battery cells can have other geometric shapes.

[0032] Preferably, the multitude of battery cells are arranged next to each other.

[0033] Preferably, the plurality of battery cells are arranged substantially parallel to the first flow direction and / or substantially parallel to the second flow direction. For example, the battery cells can be arranged along the first direction, such as the x-direction.

[0034] The term "parallel," as used in this disclosure, refers to an substantially parallel alignment of, for example, surfaces, axes, or directions of extension, whereby a deviation of a few degrees, for example, up to 5° or even up to 10°, from an exact parallel alignment is still considered an "essentially parallel alignment." Similarly, the term "perpendicular," as used in this disclosure, refers to an substantially perpendicular alignment of, for example, surfaces, axes, or directions of extension, whereby a deviation of a few degrees, for example, up to 5° or even up to 10°, from an exact perpendicular alignment is still considered an "essentially perpendicular alignment."

[0035] According to another independent aspect of the present disclosure, a vehicle, in particular a motor vehicle, is specified. The vehicle comprises the traction battery according to the embodiments of the present disclosure.

[0036] The term "vehicle" includes cars, trucks, vans, buses, motorhomes, motorcycles, etc., used for the transport of people, goods, etc. In particular, the term includes motor vehicles for passenger transport.

[0037] Preferably, the vehicle is a hybrid or electric vehicle.

[0038] Depending on the embodiment, the hybrid or electric vehicle can be a pure electric vehicle (BEV) or a plug-in hybrid vehicle (PHEV). Brief description of the drawings

[0039] Examples of the manifestation of the revelation are shown in the figures and are described in more detail below. They show: Fig. 1 schematically a vehicle with a traction battery according to embodiments of the present disclosure, Fig. 2 schematically a top view of a traction battery for a vehicle according to embodiments of the present disclosure, Fig. 3 schematically a side view of a traction battery for a vehicle according to embodiments of the present disclosure, and Fig. 4 schematically a side view of a traction battery for a vehicle according to further embodiments of the present disclosure. Implementations of the revelation

[0040] Unless otherwise noted, the same reference symbols are used for identical and equivalent elements in the following.

[0041] Fig. Figure 1 schematically shows a vehicle 10 with a traction battery 100 according to embodiments of the present disclosure.

[0042] Preferably, the vehicle 10 is a hybrid or electric vehicle. According to the embodiments, the hybrid or electric vehicle can be a battery electric vehicle (BEV) or a plug-in hybrid electric vehicle (PHEV).

[0043] The drive battery 100, also called traction battery or high-voltage storage, comprises a large number of battery cells 102. The large number of battery cells 102 can be connected together to provide the total energy and voltage required for an electric drive of the vehicle 10.

[0044] In some embodiments, the plurality of battery cells can be 102 rechargeable lithium-ion cells, but the present disclosure is not limited to this.

[0045] Fig. Figure 2 schematically shows a top view of a traction battery 100 for a vehicle according to embodiments of the present disclosure.

[0046] In the Fig. Figure 2 represents a first direction 1, a second direction 2, and a third direction 3, which can be perpendicular to each other. The first direction 1 can be an x-direction, the second direction 2 can be a y-direction, and the third direction 3 can be a z-direction.

[0047] The length of the drive battery 100 can be defined in the first direction 1. The thickness of the drive battery 100 can be defined in the second direction 2. The height of the drive battery 100 can be defined in the third direction 3.

[0048] The traction battery 100 comprises several battery cells (not shown). The multiple battery cells can be arranged essentially parallel to each other, for example along the second direction 2.

[0049] The plurality of battery cells can be arranged side by side, for example along the first direction 1. The plurality of battery cells can be rechargeable lithium-ion cells, but the present disclosure is not limited to this.

[0050] The traction battery 100 comprises a first cooling arrangement 110 for the multiple battery cells, wherein the first cooling arrangement 110 is arranged above and / or below the multiple battery cells with respect to the third direction 3 and is supplied with a first coolant, such as water or another suitable medium.

[0051] In some embodiments, the traction battery 100 further comprises a second cooling arrangement 120, through which a second coolant flows, which also flows around the battery cells. The first cooling arrangement 110 can be configured to temper, and in particular cool, the second coolant of the second cooling arrangement 120. In other words, the first cooling arrangement 110 can serve as a heat exchanger for the second coolant of the second cooling arrangement 120.

[0052] The second cooling arrangement 130 can be configured for direct immersion temperature control (e.g., immersion cooling) of the battery cells. Direct immersion temperature control of battery cells is a temperature control technique in which the battery cells are completely immersed in a medium, such as a dielectric, to transfer heat directly and efficiently.

[0053] The first cooling arrangement 110 comprises several cooling levels 112, each through which the first coolant flows. The several cooling levels 112 can be arranged essentially parallel to each other, for example along the second direction 2.

[0054] In some embodiments, the multiple cooling levels 112 can be plate-shaped. The length of the cooling level 112 can be defined in the first direction 1. The thickness of the cooling level 112 can be defined in the second direction 2. The height of the cooling level 112 can be defined in the third direction 3.

[0055] In some embodiments, several heat exchanger sections of the second cooling arrangement 120 are arranged between the cooling levels 112 of the first cooling arrangement 110, so that the second coolant of the second cooling arrangement 120 can be tempered by the first cooling arrangement 110. For this purpose, the several heat exchanger sections can include fins 122 around which the second coolant, which comes from the battery cells or from the third direction 3, flows. This can increase the efficiency of the heat exchange.

[0056] In some embodiments, the multiple heat exchanger sections and the multiple cooling levels 112 are arranged alternately. In particular, each heat exchanger section can be arranged between two adjacent cooling levels 112 or be enclosed on both sides by the adjacent cooling levels 112. The multiple heat exchanger sections and the multiple cooling levels 112 can, for example, be arranged alternately along the second direction 2, such as the y-direction.

[0057] The first cooling arrangement 110 comprises at least one first inlet 114A and at least one first outlet 116A at a first end region of the multiple cooling levels 112, as well as at least one second inlet 114B and at least one second outlet 116B at a second end region of the multiple cooling levels 112. The first end region and the second end region are opposite end regions of the multiple cooling levels 112, such that at least one first cooling level of the multiple cooling levels 112 is traversed by the first coolant in a first flow direction SR1, and at least one second cooling level of the multiple cooling levels 112 is traversed by the first coolant in a second flow direction SR2 opposite to the first flow direction SR1.

[0058] This means that at least one inlet and one outlet are arranged on opposite sides of the cooling levels 112, allowing flow to pass through the cooling levels 112 in opposite directions without any reversals. In other words, there is no U-flow with reversals. This reduces the temperature gradient, ensuring uniform temperature control across the entire surface of the drive battery 100. Furthermore, pressure losses, which occur in a U-flow, are reduced. As a result, the efficiency of the temperature control mechanism is improved, which in turn ensures the performance and service life of the drive battery 100. Additionally, the diameter of the inlet and outlet lines can be smaller due to the doubling of the arrangement on both sides, allowing for better use of available space, especially with small z-dimensions.

[0059] The first flow direction SR1 is essentially parallel to the first direction 1. The second flow direction SR2 is essentially parallel to the first direction 1. For example, the first direction 1 may be an x-direction, particularly in a top view of the propulsion battery 100. In this case, the first flow direction SR1 may be a positive x-direction, and the second flow direction SR2 may be a negative x-direction.

[0060] In some embodiments, the multiple cooling levels 112 are alternately traversed by the first coolant in the first flow direction SR1 and the second flow direction SR2. In particular, adjacent cooling levels 112 can be traversed in opposite flow directions. For example, a first cooling level can be traversed in the first flow direction SR1, a second cooling level can be traversed in the second flow direction SR2, a third cooling level can be traversed in the first flow direction SR1, a fourth cooling level can be traversed in the second flow direction SR2, and so on.

[0061] In some embodiments, a third flow direction SR3 of the second coolant of the second cooling arrangement 120 is essentially perpendicular to the first flow direction SR1 and / or essentially perpendicular to the second flow direction SR2 of the first coolant of the first cooling arrangement 110. For example, the third flow direction SR3 of the second coolant can be essentially parallel to the third direction 3. In other words, the second coolant can be introduced into the heat exchanger sections of the second cooling arrangement 120, i.e., the area between the cooling levels 112, from above and / or from below.

[0062] Fig. Figure 3 schematically shows a side view of a traction battery 100 for a vehicle according to embodiments of the present disclosure. At the top in the Fig. Figure 3 shows a cooling plane 112A in which the coolant flows in the second flow direction SR2, and below in the Fig. Figure 3 shows another cooling level 112B, in which the coolant flows in the first flow direction SR1.

[0063] In the example of the Fig. 3. The at least one first inlet 114A and the at least one first outlet 116A are arranged one above the other in the z-direction. Similarly, the at least one second inlet 114B and the at least one second outlet 116B are arranged one above the other in the z-direction.

[0064] Fig. Figure 4 schematically shows a side view of a traction battery 100 for a vehicle according to further embodiments of the present disclosure.

[0065] In the example of the Fig. In section 4, at least one first inlet 114A and at least one first outlet 116A are arranged side by side in the x-direction. Similarly, at least one second inlet 114B and at least one second outlet 116B are arranged side by side in the x-direction.

[0066] Although the invention has been further illustrated and explained in detail by means of preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived from them by a person skilled in the art without departing from the scope of protection of the invention. It is therefore clear that a multitude of possible variations exist. It is also clear that the embodiments mentioned as examples are truly only examples and 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, whereby the person skilled in the art, with knowledge of the disclosed inventive concept, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without leaving the scope of protection defined by the claims and their legal equivalents, such as further explanations in the description.

Claims

[1] Traction battery (100) for a vehicle (10), comprising: - several battery cells; and - a first cooling arrangement (110) for the multiple battery cells, wherein the first cooling arrangement (110) is arranged adjacent to the multiple battery cells and comprises multiple cooling levels (112) for a first coolant, wherein the first cooling arrangement (110) comprises at least one first inlet (114A) and at least one first outlet (116A) at a first end region of the multiple cooling levels (112) as well as at least one second inlet (114B) and at least one second outlet (116B) at a second end region of the multiple cooling levels (112), such that at least one first cooling level of the multiple cooling levels (112) is supplied with coolant in a first flow direction (SR1) and at least one second cooling level of the multiple cooling levels (112) is supplied with coolant in a second flow direction (SR2) opposite to the first flow direction (SR1). [2] Traction battery (100) according to claim 1, wherein the multiple cooling levels (112) are plate-shaped and / or planar. [3] Drive battery (100) according to claim 1 or 2, wherein the multiple cooling levels (112) are alternately supplied with coolant in the first flow direction (SR1) and the second flow direction (SR2), in particular wherein adjacent cooling levels (112) are supplied with coolant in opposite flow directions (SR1, SR2). [4] Drive battery (100) according to one of claims 1 to 3, wherein the first flow direction (SR1) and the second flow direction (SR2) lie in one plane, and wherein: - the at least one first inlet (114A) and the at least one first outlet (116A) are arranged essentially perpendicular to the plane above one another and / or the at least one second inlet (114B) and the at least one second outlet (116B) are arranged essentially perpendicular to the plane above one another; or - the at least one first inlet (114A) and the at least one first outlet (116A) are arranged next to each other in the plane and / or the at least one second inlet (114B) and the at least one second outlet (116B) are arranged next to each other in the plane. [5] Traction battery (100) according to one of claims 1 to 4, further comprising a second cooling arrangement (120) which is provided for a second coolant which flows around the multiple battery cells. [6] Drive battery (100) according to claim 5, wherein a flow direction (SR3) of the second coolant is substantially perpendicular to the first flow direction (SR1) and / or substantially perpendicular to the second flow direction (SR2). [7] Traction battery (100) according to claim 5 or 6, wherein the first cooling arrangement (110) is configured to temper the second coolant of the second cooling arrangement (120), in particular wherein the second cooling arrangement (120) comprises several heat exchanger sections between the cooling levels (112) of the first cooling arrangement (110) to temper the second coolant through the first cooling arrangement (110). [8] Traction battery (100) according to claim 7, wherein the multiple heat exchanger sections and the multiple cooling levels (112) are arranged alternately. [9] Traction battery (100) according to any one of claims 5 to 8, wherein: - the second cooling arrangement (120) is set up for direct immersion temperature control of battery cells; and / or - the second coolant is a dielectric. [10] Vehicle (10), in particular motor vehicle, comprising the traction battery (100) according to any one of claims 1 to 9.

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