Battery pack

Abstract

The present disclosure provides a battery pack and a battery system including the same. The battery pack includes a battery pack case having accommodation spaces in which cell stacks are respectively accommodated, a partition wall separating adjacent cell stacks among the cell stacks, a pressure wall having a first side contacting end portions of the cell stacks and connected to the partition wall or integrally formed with the partition wall, and a reinforcement structure on a second side of the pressure wall for reinforcing the partition wall. The reinforcement structure includes an outer wall spaced apart from the pressure wall and extending in parallel to the pressure wall, and a plurality of reinforcement ribs between the pressure wall and the outer wall. The reinforcement ribs have a first contact height in contact with the pressure wall and a second contact height in contact with the outer wall, the second contact height being less than a total pressure wall height to an upper edge of the pressure wall.

Description

Technical Field

[0001] The embodiments of this disclosure relate to battery packs. Background Technology

[0002] A battery pack is a group of any number (typically identical) battery modules or individual battery cells. Battery modules and their individual cells can be configured in series, parallel, or a combination of both to provide desired voltage, capacity, and / or power density. The components of a battery pack include individual battery modules and interconnects that provide conductivity between the battery modules.

[0003] The mechanical integration of the battery pack is achieved through appropriate mechanical connections between individual components, such as between battery modules and between battery modules and the vehicle's support structure. These connections should remain functional and safe throughout the average lifespan of the battery system. Furthermore, installation space and interchangeability specifications should be met, especially in mobile applications.

[0004] Mechanical integration of the battery module can be achieved by providing a carrier frame and positioning the battery module thereon. Securement of individual battery cells or the battery module can be achieved through mating recesses in the frame or via mechanical interconnects such as bolts or screws. In some cases, the battery module is confined by fastening side panels to the sides of the carrier frame. Additionally, cover plates can be fixed to the top and bottom of the battery module.

[0005] The battery pack's carrier frame is mounted to the vehicle's load-bearing structure. When the battery pack needs to be secured to the bottom of the vehicle, a mechanical connection can be established from the bottom side via bolts, for example, passing through the carrier frame. The frame is typically made of aluminum or aluminum alloy to reduce the overall weight of the structure.

[0006] Traditional battery systems, regardless of their modular structure, typically include a battery casing that acts as an enclosure to seal the battery system relative to the environment and provide structural protection for the system's components. Encapsulated battery systems are usually installed as a whole into their application environment, such as electric vehicles. Therefore, replacing a defective system component, such as a defective battery sub-module, requires first disassembling the entire battery system and removing its casing. Even defects in small and / or inexpensive system components may necessitate the disassembly and replacement of the entire battery system and its individual repair. This process is cumbersome because high-capacity battery systems are expensive, large, and heavy, and storing bulky battery systems, for example, in a mechanic's workshop is difficult.

[0007] As the location of both active and passive components in a battery system, the battery casing plays a crucial role in the functionality, safety, and lifespan of the energy storage system. The battery casing protects sensitive components from harmful environments such as water, moisture, and dust, making it essential for long-term safe and reliable operation. Because traction batteries are typically located outside the vehicle body, usually in the chassis area, the casing is directly exposed to extreme environmental conditions such as temperature fluctuations, moisture, splashes, salt spray, dust, and gravel. Therefore, high mechanical stability and corrosion resistance are essential even under corrosive external conditions. In addition to environmental influences that primarily affect the casing surface or casing seal, the internal and external fastening systems are also particularly important under vehicle operating conditions.

[0008] The individual cells in a battery cell stack can expand due to various reasons, including swelling, aging, and / or charging. This expansion can exert forces on the battery pack housing, for example, in the longitudinal direction. In cell-to-pack type battery pack housings, these forces are transmitted directly to the battery pack housing.

[0009] Such forces can induce high stress in critical areas or locations within the battery pack casing. For example, the partition walls between stacked battery cells are key components related to mechanical stability. Reinforcing structures, including ribs, have been used to increase the mechanical robustness of the battery pack casing. Summary of the Invention

[0010] This disclosure is defined by the appended claims and their equivalents. The following description is limited by this limitation. Any disclosure outside the scope of the claims and their equivalents is intended for illustrative and comparative purposes.

[0011] The aforementioned reinforced topology may be insufficient to mitigate the localized high stresses occurring in the separator walls. Therefore, there is a need for improved designs for the reinforced structure, which can better resist higher forces and / or prevent cracking, while improving the mechanical robustness of the battery pack casing relative to the stacking expansion of the battery cells.

[0012] According to one embodiment of this disclosure, a battery pack is provided. The battery pack includes a battery pack housing having multiple receiving spaces. Multiple battery cells are stacked and disposed in respective receiving spaces. The battery pack includes a partition wall configured to separate adjacent stacks of battery cells from each other. A pressure wall, including a first side contacting the end portions of the battery cell stacks, is connected to or integrally formed with the partition wall. The battery pack also includes a reinforcing structure for reinforcing the partition wall, the reinforcing structure being provided on a second side of the pressure wall opposite to the first side. The reinforcing structure includes an outer wall spaced apart from and extending parallel to the pressure wall. The reinforcing structure includes multiple reinforcing ribs between the pressure wall and the outer wall, the reinforcing ribs contacting the outer wall and the pressure wall from a bottom portion in a height direction. The reinforcing ribs have a first contact height contacting the pressure wall and a second contact height contacting the outer wall, the second contact height being less than the total pressure wall height at the upper edge of the pressure wall.

[0013] According to another embodiment of this disclosure, a battery system including the battery pack described above is provided.

[0014] According to another embodiment of this disclosure, a vehicle is provided that includes the battery pack described above.

[0015] Other embodiments of this disclosure may be learned from the claims and / or the following description. Attached Figure Description

[0016] The aspects and features of this disclosure will become apparent to those skilled in the art from the detailed description of embodiments thereof with reference to the accompanying drawings, wherein:

[0017] Figure 1 This is a perspective view of the battery pack according to an embodiment.

[0018] Figure 2A This is a partial perspective view of the battery pack according to a comparative embodiment, showing the stress distribution.

[0019] Figure 2B yes Figure 2A A partial sectional view of the partition wall shown.

[0020] Figure 3A This is a partial perspective view of a battery pack according to an embodiment of the present disclosure.

[0021] Figure 3B This is a top view of a battery pack according to an embodiment of the present disclosure.

[0022] Figure 3C It is to observe along from one angle Figure 3B A cross-sectional view of the battery pack taken along line AA.

[0023] Figure 3D Is with Figure 3C The same view shown illustrates the stress distribution.

[0024] Figure 4A This is a partial perspective view of a battery pack according to another embodiment of the present disclosure.

[0025] Figure 4B It is based on the embodiments of this disclosure. Figure 4A The side view of the battery pack shown.

[0026] Figure 4C This is a perspective view of a battery pack according to an embodiment of the present disclosure, showing the stress distribution. Detailed Implementation

[0027] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. Aspects and features of the embodiments and methods of implementation thereof will be described with reference to the drawings. However, this disclosure may be implemented in a variety of different forms and should not be construed as limited to the embodiments shown herein. Rather, these embodiments are provided as examples so that this disclosure will be thorough and complete and will fully convey to those skilled in the art the aspects and features of this disclosure.

[0028] Therefore, processes, elements, and techniques not considered essential to a full understanding of the aspects and features of this disclosure by one of ordinary skill in the art may be omitted or may be described only briefly. The same reference numerals denote the same elements.

[0029] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of “may” refers to “one or more embodiments of this disclosure.” When expressions such as “at least one of…” and “any one of…” follow a list of elements, they modify the entire list of elements, not individual elements within that list. For example, the expression “at least one of a, b, or c” indicates only a, only b, only c, both a and b, both a and c, both b and c, all a, b, and c, or variations thereof. As used herein, the terms “use,” “using…,” and “being used” may be considered synonymous with the terms “utilize,” “using…,” and “being exploited,” respectively. As used herein, the terms “substantially,” “about,” and similar terms are used as approximate terms, not terms of degree, intended to describe inherent biases in measurements or calculations that would be recognized by one of ordinary skill in the art.

[0030] It will be understood that although the terms "first" and "second" are used to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of this disclosure, a first element may be named a second element, and similarly, a second element may be named a first element.

[0031] The terminology used herein is for describing embodiments of the present disclosure and is not intended to limit the disclosure. As used herein, the singular form “a” is also intended to include the plural form unless the context clearly indicates otherwise. It will be further understood that the terms “comprising,” “including,” “including,” and / or “containing” specify the stated properties, areas, fixed quantities, steps, processes, elements, components, and combinations thereof, but do not exclude other properties, areas, fixed quantities, steps, processes, elements, components, and combinations thereof.

[0032] It will also be understood that when a membrane, region, or element is referred to as being "above" or "on" another membrane, region, or element, it may be directly on the other membrane, region, or element, or there may be an intermediate membrane, region, or element.

[0033] In this document, the terms "upper" and "lower" are defined according to the z-axis. For example, the upper cover is positioned above the z-axis, and the lower cover is positioned below it. In the accompanying drawings, the dimensions of the components may be exaggerated for clarity. For example, the dimensions or thickness of each component may be arbitrarily shown in the drawings for illustrative purposes, and therefore the embodiments of this disclosure should not be construed as limited thereto.

[0034] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will be further understood that terms such as those defined in common dictionaries shall be interpreted as having a meaning consistent with their meaning in the relevant field and / or the context of this specification, and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0035] Those skilled in the art will understand that, in view of the entirety of this disclosure, each suitable feature of the various embodiments of this disclosure may be combined in part or in whole, or combined with one another, and may be technically interlocked and operated in various suitable ways, and each embodiment may be implemented independently or in combination with one another in any suitable manner, unless otherwise stated or implied.

[0036] According to an embodiment of this disclosure, a battery pack includes a battery pack housing having multiple receiving spaces. Multiple battery cells are stacked and disposed (or arranged) in the receiving spaces. The battery pack includes: a partition wall for separating adjacent stacks of battery cells from each other; and a pressure wall having a first side that contacts the end portions of the battery cell stacks and is connected to or integrally formed with the partition wall. The battery pack also includes a reinforcing structure on a second side of the pressure wall opposite to the first side for reinforcing the partition wall. The reinforcing structure includes an outer wall spaced apart from and extending parallel to the pressure wall. The reinforcing structure includes multiple reinforcing ribs between the pressure wall and the outer wall. The reinforcing ribs contact the outer wall and the pressure wall from the bottom of the battery pack housing in a height direction. The reinforcing ribs have a first contact height contacting the pressure wall and / or a second contact height contacting the outer wall, the second contact height being less than the total pressure wall height of the upper edge of the pressure wall.

[0037] Reinforcing ribs are arranged between the pressure wall and the outer wall. The reinforcing ribs can be integral components of the housing. In other words, reinforcing ribs can be stiffeners or reinforcements. Reinforcing ribs can include flat sheet members, such as sheet metal members, but this disclosure is not limited thereto. Reinforcing ribs can transfer forces from the pressure wall to the outer wall.

[0038] Therefore, it can be expected that the structure should extend the reinforcing ribs to the upper edge of the pressure wall so that the pressure wall can be optimally supported by the outer wall to reduce stress at the upper edge of the partition wall. However, this design results in the tensile stress in the upper edge of the partition wall remaining critical. Furthermore, for encapsulation reasons, the dimensions of the partition wall and the rounded transition between the partition wall and the pressure wall are limited.

[0039] According to embodiments of this disclosure, as described below, a non-intuitive and surprising solution was discovered and quantified through FEM analysis, wherein the stress applied in the upper edge of the partition wall is significantly reduced because the first contact height and / or the second contact height is less than the total pressure wall height of the upper edge of the pressure wall. For example, by removing the reinforcing ribs in the upper portion of the pressure wall, the upper portion of the pressure wall becomes more elastic / flexible, thereby reducing the amount of stress applied in the critical upper edge. This finding is supported by the determination of the stress tensor of the underlying topology and FEM analysis. Therefore, higher forces can be resisted and / or crack formation can be prevented. Resistance to higher forces can allow for larger monomer forms or smaller monomer separator thicknesses, thereby increasing energy density.

[0040] According to the implementation, the first contact height and / or the second contact height is less than about 90%, less than about 80%, or less than about 70% of the total pressure wall height. This ensures that the effect of reducing tensile stress in the upper edge of the partition wall is sufficiently high to reduce the risk of reaching the critical (tensile) stress.

[0041] According to one embodiment, the reinforcing rib has a first contact height in the contact area, which corresponds to the location where the pressure wall contacts the partition wall. Therefore, in this embodiment, the first contact height is directly located at the location where force is introduced into the partition wall. Reducing the height of the reinforcing rib at the contact area has an improved stress reduction effect. For example, the maximum tension can be split into two force paths flowing into the partition wall at the contact area, resulting in a reduction in tensile stress in the upper section of the partition wall. In other words, the contact area (e.g., the contact zone) refers to the area (e.g., the region) where the pressure wall and the partition wall meet (e.g., where they contact). The contact area can have a vertically extending linear region corresponding to the contact sidewall of the partition wall.

[0042] According to one embodiment, the reinforcing rib has a cut that extends to a first contact height in a direction opposite to the height direction (i.e., in a direction toward the bottom). The cut can provide a reduced first contact height. The cut can be an area where material without the reinforcing rib contacts the pressure wall. The cut can correspond to a contact area. The cut of the reinforcing rib can reduce the tensile stress at the top edge of the partition wall to a tolerable level. For example, due to the cut, the maximum tension can be split into two main force paths, resulting in a reduction in localized stress in the upper section of the partition wall. This can be intuitively understood because the cut provides greater flexibility in the upper portion due to its downward extension. The pressure wall can bend outwards due to the slight outward bulge of the cell stacks. This can cause a second main force flow to separate from the first main force flow below the first main force flow along the edge of the partition wall. Therefore, by enabling the second main force flow, the tensile stress at the upper edge of the partition wall is reduced.

[0043] According to the embodiment, the cut is formed such that the force applied to the pressure wall by the stack of battery cells is divided into two highly separated main forces introduced into the separator wall. This can result in a region with reduced stress between the separating force paths, leading to an effective reduction of stress in the upper edge of the separator wall.

[0044] According to one implementation, the cut is formed by removing a portion of the reinforcing rib. For example, the cut can be formed through a process that removes the reinforcing rib material. This allows for easy modification of the battery pack, which may have reinforcing ribs extending to the upper edge of the pressure wall, or it may be easily integrated into conventional manufacturing processes, for example, after casting.

[0045] According to one embodiment, the reinforcing rib includes at least one reinforcing protrusion that extends in the height direction relative to the bottom (i.e., lowest point) of the cut, toward the upper edge, in contact with the pressure wall. The at least one reinforcing protrusion is positioned laterally displaced from the contact area corresponding to the location where the pressure wall contacts the partition wall. The reinforcing protrusion, such as a reinforcing finger, can ensure a sufficiently high force flow in the upper edge of the partition wall to counteract the outward bending of the upper portion of the pressure wall.

[0046] According to one embodiment, the reinforcing rib forms two uncovered portions on the second side of the pressure wall. These two uncovered portions are separated from each other by a contact portion of the reinforcing rib, which contacts the pressure wall at a contact area corresponding to the position where the pressure wall contacts the partition wall. This configuration can further stabilize the structure of the partition wall.

[0047] According to one embodiment, the outer wall has a total outer wall height that is less than the total pressure wall height of the upper edge of the pressure wall. According to another embodiment, the total outer wall height corresponds to the second contact height. Thus, because the outer wall decreases in height relative to the pressure wall and the height of the reinforcing ribs decreases in the direction away from the partition wall, a reduction in stress applied to the upper portion of the partition wall is achieved.

[0048] According to the embodiment, the local height of the reinforcing rib decreases continuously from the first contact height toward the second contact height of the outer wall. Therefore, a larger force can be accommodated in the reinforcing rib.

[0049] According to the implementation, the descending slope of the reinforcing rib is gentler in the first region of the pressure wall and steeper in the second region of the outer wall. This optimizes the force input in the reinforcing rib and reduces the occurrence of high stress.

[0050] According to one embodiment, the reinforcing rib includes a first branch rib portion and a second branch rib portion, which are connected to the pressure wall at positions corresponding to the locations where the pressure wall contacts the partition wall, and extend outward from these positions by branching at an angle (e.g., an inclination angle) relative to the extending direction of the partition wall. Therefore, two force flows can be provided to each branch rib portion. This optimizes the force input in the reinforcing rib and reduces the load on the partition wall.

[0051] According to one embodiment, the battery pack housing is a casting. For example, the battery pack housing may be a high-pressure die-casting. Die casting is a metal casting process in which molten metal is forced into a molding cavity under high pressure. For example, the battery pack housing may include aluminum. Cast battery pack housings can provide excellent surface properties.

[0052] According to the implementation method, multiple reinforcing ribs are integrally formed with the pressure wall and the outer wall. Therefore, additional stress at the material transition points can be avoided.

[0053] According to embodiments of this disclosure, a battery system is provided that includes a battery pack as described herein.

[0054] According to embodiments of this disclosure, a vehicle is provided that includes a battery pack as described herein.

[0055] Figure 1 This is a perspective view of a battery pack 100 including a battery pack housing 10 and a stack of battery cells 20 according to an embodiment. Figure 2A This is a partial perspective view of the battery pack, showing the stress distribution. Figure 2B yes Figure 2A A partial sectional view of the partition wall 30 shown.

[0056] Reference Figure 1 The battery pack housing 10 has multiple receiving spaces 12. In this embodiment, three receiving spaces 12 are provided, but the present disclosure is not limited thereto.

[0057] like Figure 1 As shown, multiple battery cell stacks 20 are arranged. The battery cell stacks 20 are disposed in corresponding receiving spaces 12 (this arrangement is indicated by arrows, and for convenience, in...). Figure 2A The battery cell stack 20 is omitted in this embodiment. The battery cell stack 20 is mechanically and / or adhesively bonded to the battery pack housing 10, for example. The battery cell stack 20 may be directly bonded to the battery pack housing 10. In this embodiment, the module frame may be omitted, but this disclosure is not limited thereto. Each battery cell stack 20 includes a plurality of battery cells 22.

[0058] The battery pack housing 10 further includes partition walls 30. The partition walls 30 separate adjacent battery cell stacks 20 from each other. In this embodiment, two partition walls 30 are provided to separate three battery cell stacks 20 from each other. In other embodiments, one or more partition walls 30 may be provided.

[0059] The battery pack housing 10 further includes pressure walls 40. The pressure walls 40 have a first side 44 that contacts an end portion 24 of the battery cell stack 20 when the battery cell stack 20 is disposed in the receiving space 12. For example, two pressure walls 40 may be respectively disposed on opposite end portions 24 of the battery cell stack 20. Thus, for example, two end portions 24 of the battery cell stack 20 may contact corresponding pressure walls 40. The pressure walls 40 are connected to or integrally formed with the partition wall 30. The battery cell stack 20 can withstand a force F (see example...) Figure 2A The force F is applied to the pressure wall 40. This force can be generated due to, for example, cell swelling, aging, or charging. The force F acting on the pressure wall 40 needs to be resisted by the battery pack housing 10 and the partition wall 30, as explained in more detail below.

[0060] Furthermore, such as Figure 1 As shown, the battery pack housing 10 includes an outer wall 60. The outer wall 60 is spaced apart from the second side 46 of the pressure wall 40 by, for example, a distance (e.g., a predetermined distance). The outer wall 60 may extend in a direction parallel to or substantially parallel to the pressure wall 40. Therefore, the distance between the pressure wall 40 and the outer wall 60 may be constant (or substantially constant) along and relative to the pressure wall 40.

[0061] The battery pack housing 10 can be a casting (e.g., a cast component), such as high-pressure casting. For example, the pressure wall 40 and the outer wall 60 can be integrally formed in the casting. In this way, for example, by reducing or omitting fastening members used in manufacturing and reducing stress applied at mechanical connections, an integrated battery pack housing 10 with reduced material and complexity can be obtained.

[0062] refer to Figure 2A The diagram shows a perspective view of a comparative embodiment of the battery pack housing and a calculated stress (e.g., tensile stress) distribution to illustrate the induced local tensile stress. Figure 2B yes Figure 2A The diagram shows a perspective view of the partition wall 30 of the comparative battery pack housing. Applied to... Figure 2A The distribution of tensile stress in the components of the battery pack housing 10 shown can be obtained through simulation using the finite element method (FEM).

[0063] Figure 2A The stress response is illustrated as the stress distribution of the partition wall 30 and the pressure wall 40 in response to a force F applied to the pressure wall 40 by the battery cell stack 20. The force F can be generated due to swelling of the battery cells, charging of the battery cells, or aging, but this disclosure is not limited thereto. A comparative example may include reinforcing ribs between the pressure wall 40 and the outer wall 60. Figure 2A and 2B (not shown in the diagram), which extends from the bottom portion 14 of the battery pack housing 10 to the total pressure wall height Hp to reduce the tensile stress acting on the partition wall 30.

[0064] However, as Figure 2A As shown, high stress, such as tensile stress, is applied in the partition wall 30 between the battery cell stacks 20. For example, the tensile stress increases in the height direction H and is close to the pressure wall 40 on the upper edge 32 of the partition wall 30 and the contact area between the partition wall 30.

[0065] For detailed reference Figure 2A FEM analysis shows that even if the reinforcing ribs extend to the upper edge 42 of the pressure wall 40, local maximum tensile stress will still occur at the upper edge 32 of the partition wall 30. Figure 2AThe force F1 in the equation represents the force entering the partition wall 30. This force F1 results in a critical region 34 with maximum tensile stress, which... Figure 2A As shown in the figure, the stress tensor exhibits a maximum value. Critical region 34 is also present. Figure 2B The force F applied by the battery cell stack 20 can lead to a critical stress in the upper edge 32 of the separator wall 30, which can result in lower stress resistance and / or crack formation in the separator wall 30.

[0066] According to the following... Figures 3A-3D and Figures 4A-4C In various embodiments of the described battery pack 100, tensile stress in the upper edge 32 (e.g., critical region 34) of the partition wall 30 is reduced, and thus the stress resistance of the battery pack 100 is improved and / or crack formation is prevented. Simulation methods such as topology optimization can be used as tools to generate the described structural topology to reduce stress at critical locations, thereby enabling the battery pack housing 10 to resist higher forces.

[0067] Figure 3A This is a partial perspective view of the battery pack 100 according to an embodiment. Figure 3B yes Figure 3A A top view of the battery pack 100 shown. Figure 3C This is a cross-sectional view of the battery pack 100 taken along line AA from one angle. Figure 3D Is with Figure 3C The same view is shown, and the stress distribution is illustrated.

[0068] The battery pack 100 includes a reinforcing structure 50. The reinforcing structure 50 strengthens the partition wall 30 to resist the induced forces described above. For example, the reinforcing structure 50 reduces the force at the upper edge 32 (i.e., in the critical region 34 of the partition wall 30, see example...) Figure 2B The tensile stress at ( ) location.

[0069] The reinforcing structure 50 is disposed on the second side 46 of the pressure wall 40 opposite to the first side 44. The reinforcing structure 50 includes an outer wall 60, which is spaced apart from and extends parallel to the pressure wall 40.

[0070] The reinforcing structure 50 also includes a plurality of reinforcing ribs 70 between the pressure wall 40 and the outer wall 60. The reinforcing ribs 70 may be integrally formed with the pressure wall 40 and / or the outer wall 60 as part of the casting process.

[0071] The reinforcing rib 70 contacts the outer wall 60 and the pressure wall 40 (e.g., extending between the outer wall 60 and the pressure wall 40). For example, as... Figure 4B As shown in the top view, the reinforcing rib 70 extends to the outer wall 60 according to the topology.

[0072] Relative to the pressure wall 40, the reinforcing rib 70 extends from the bottom portion 14 in the height direction H of the battery pack housing 10 (see example). Figure 3A )extend.

[0073] Now for reference Figure 3C The reinforcing rib 70 has a first contact height Hc1 that contacts the pressure wall 40. The first contact height Hc1 is the height at which the reinforcing rib 70 contacts the pressure wall 40 on the second side 46 of the pressure wall 40.

[0074] According to the illustrated embodiment, the first contact height Hc1 of the reinforcing rib 70 is less than the total pressure wall height Hp of the upper edge 42 of the pressure wall 40. For example, a gap is provided between the upper edge 42 of the pressure wall 40 and the upper end of the reinforcing rib 70.

[0075] Therefore, compared with the conventional example where the reinforcing rib 70 extends to the top of the upper edge 42 of the pressure wall 40, the reinforcing rib 70 according to the embodiment of the present disclosure does not extend to the top of the upper edge 42 of the pressure wall 40 (e.g., has an upper edge spaced apart from the top of the upper edge 42 of the pressure wall 40 in the height direction).

[0076] FEM results confirm a reduction in stress introduced into the upper edge 32 of the partition wall 30, as a non-intuitive effect caused by the reduction in the height of the reinforcing rib 70. This finding is obtained as follows: Figure 3D The FEM results shown support this, illustrating the reduction in tensile stress at the upper edge 32 of the partition wall 30. This allows the battery pack housing 10 to withstand higher forces and prevent potential cracking.

[0077] according to Figures 3A to 3D In one example implementation, the upper edge 42 of the pressure wall 40 may be higher than the upper edge 32 of the partition wall 30 (e.g., above the upper edge 32 of the partition wall 30). For example, the contact height Hc1 may be less than (or lower than) the upper edge 32 of the partition wall 30. In other implementations, the upper edge 42 of the pressure wall 40 may be equal in height to the upper edge 32 of the partition wall 30 compared to the upper edge 32 of the partition wall 30.

[0078] The first contact height Hc1 can be less than about 90% of the total pressure wall height Hp of the pressure wall 40. In another embodiment, the first contact height Hc1 can be less than about 80% of the total pressure wall height Hp, or it can be less than about 70% of the total pressure wall height Hp. Therefore, a significant reduction in stretching can be achieved.

[0079] Reference Figure 3B and Figure 3CThe reinforcing rib 70 has a first contact height Hc1 at a contact area 48 that contacts the pressure wall 40, corresponding to the location where the pressure wall 40 contacts the partition wall 30. The contact area 48 (e.g., contact zone) refers to the region (e.g., area) where the pressure wall 40 and the partition wall 30 meet (e.g., where the pressure wall 40 and the partition wall 30 contact each other). The contact area 48 may have a vertically extending linear region corresponding to the contact sidewall of the partition wall 30. Therefore, for example, the reduction in the height of the reinforcing rib 70 at the location where the first contact height Hc1 is measured occurs directly at the location where force is applied to the partition wall 30. This allows for a reduction in stress in the upper edge 32 of the partition wall 30.

[0080] The reduction in height of the reinforcing rib 70 can be formed by a cut 71. The cut 71 can extend at the pressure wall 40 in a direction opposite to the height direction H to a first contact height Hc1. Therefore, the cut 71 can provide a reduced first contact height Hc1. The cut 71 can define (e.g., provide) an area in which the material of the reinforcing rib 70 does not contact the pressure wall 40. The cut 71 can correspond to a contact area 48 (e.g., a contact zone).

[0081] Incision 71 Figure 3C As shown in the diagram. Due to the cross-sectional view, in Figure 3C Only half of the cut 71 is shown. The cut 71 extends in a bottom direction, for example, opposite to the height direction H. Figure 3D As shown, the incision 71 can cause the inducing forces F1 and F2 applied to the partition wall 30 to split.

[0082] Due to the cut 71, the force F applied to the pressure wall 40 by the battery cell stack 20 causes two highly separated first and second main forces F1, F2 to be applied to the partition wall 30. Figure 3D The diagram shows the main stressors F1 and F2, with a stress-reducing zone 36 formed by a cut 71 between them. This reduces the stress in the upper edge 32 (e.g., in areas such as...). Figure 2B The tensile stress at the critical region (point 34 indicated in the diagram) can prevent crack formation and increase stress resistance.

[0083] In this embodiment, cut 71 is the removed portion of the reinforcing rib 70. Therefore, cut 71 can be modified into the battery pack where the reinforcing rib 70 reaches the upper edge 42 of the pressure wall 40 via a cutting operation performed to remove material from the reinforcing rib 70, for example, at the contact area 48. This allows the battery pack 100 to be manufactured using existing manufacturing methods by adding a cutting or removal operation.

[0084] The boundary of the cut 71 may be provided with a reinforcing protrusion 72. For example, as Figure 3CAs shown, the reinforcing rib 70 includes at least one reinforcing protrusion 72 extending in the height direction H and contacting the pressure wall 40. For example, two reinforcing protrusions 72 may be provided, one on each side of the cut 71. The reinforcing protrusion 72 extends in the height direction H in contact with the pressure wall 40. Thus, the reinforcing protrusion 72 extends relative to the bottom portion 14 in a direction toward the upper edge 42 while maintaining a distance from the upper edge 42. The reinforcing protrusion 72 is positioned to be laterally displaced by a displacement δd from the contact area 48, which corresponds to the position where the pressure wall 40 contacts the partition wall 30. The reinforcing protrusion 72 may also define the boundary or envelope of the cut 71. The reinforcing protrusion 72 may maintain a sufficiently high force flow in the partition wall 30 to counteract any outward bending of the upper portion of the pressure wall 40.

[0085] In addition, refer to Figure 3B A specific topology of the reinforcing rib 70 can be provided to further stabilize the structure of the partition wall 30. The reinforcing rib 70 forms two uncovered portions 74 on the second side 46 of the pressure wall 40. The uncovered portions 74 are separated from each other by contact portions 73 of the reinforcing rib 70, which contact the second side 46 of the pressure wall 40 at a contact area 48 corresponding to the position where the pressure wall 40 contacts the partition wall 30. The uncovered portions 74 can be provided by (or formed by) the reinforcing rib 70, which forms branches at an angle relative to the partition wall 30 between the pressure wall 40 and the outer wall 60. This topology can further stabilize the structure of the partition wall 30.

[0086] In the following text, see references Figures 4A-4C Another embodiment is described, which can reduce the tensile stress in the upper edge 32 of the partition wall 30.

[0087] Figure 4A This is a partial perspective view of a battery pack 100 according to an embodiment of the present disclosure. Figure 4B yes Figure 4A Side view of the battery pack 100 shown. Figure 4C yes Figure 4A and Figure 4B The perspective view of the battery pack 100 shown in the figure illustrates the stress distribution. The following description will primarily focus on the stress distribution described above. Figures 3A-3D The differences in the described implementation methods are omitted, while descriptions of the same features are only briefly repeated.

[0088] In this embodiment, reference Figure 4A The reinforcing structure 50 includes a plurality of reinforcing ribs 70 with different configurations between the pressure wall 40 and the outer wall 60. The reinforcing ribs 70 contact the outer wall 60 and the pressure wall 40 and extend from the bottom portion 14 in the height direction H of the battery pack housing 10.

[0089] refer to Figure 4A and 4B In this embodiment, the second contact height Hc2 of the reinforcing rib 70 in contact with the outer wall 60 is less than the total pressure wall height Hp of the upper edge 42 of the pressure wall 40. Therefore, the second contact height Hc2 of the reinforcing rib 70 in contact with the outer wall 60 is not equal to the total pressure wall height Hp of the upper edge 42, so as to reduce the stress on the partition wall 30.

[0090] According to the embodiments shown in this disclosure, and as obtained by FEM analysis Figure 4C Stress analysis of the battery pack shown demonstrates that the stress in the upper edge 32 of the separator 30 is reduced, and can prevent stress such as... Figure 2A The indicated critical region 34. With this construction, the main force is transmitted through the reinforcing ribs 70, whose height decreases at the outer wall 60. Therefore, due to the height relationship, stress occurs in the reinforcing ribs 70, rather than at the upper edge 32 of the partition wall 30, as... Figure 4C As shown.

[0091] For example, the second contact height Hc2 can be less than approximately 90%, less than approximately 80%, or less than approximately 70% of the total pressure wall height Hp. This can achieve the effect of reducing the tensile stress in the upper edge 32.

[0092] like Figure 4B As shown in more detail, the outer wall 60 may have a total outer wall height Ho that is less than the total pressure wall height Hp of the upper edge 42 of the pressure wall 40. For example, the total outer wall height Ho of the outer wall 60 may correspond to (e.g., may be equal to) the second contact height Hc2. In this way, the pressure applied by the battery cell stack 20 can be directed downward toward the outer wall 60, which is reduced in height relative to the pressure wall 40.

[0093] like Figure 4A and Figure 4B As shown, the local height Hc of the reinforcing rib 70 can continuously decrease from the first contact height Hc1 at the pressure wall 40 toward the second contact height Hc2 at the outer wall 60. In this way, local high stress in the reinforcing rib 70 can be avoided.

[0094] According to an embodiment, the reinforcing rib 70 may have a descending ramp 77 that is gentler in the first region R1 closer to the pressure wall 40 than in the second region R2 (i.e., closer to the outer wall 60 relative to the first region R1). This may be a result of topology optimization of the reinforcing rib 70, avoiding high stress in the reinforcing rib 70 near the contact region 48.

[0095] Reference Figure 4AThe reinforcing rib 70 includes a first branch rib portion 75 and a second branch rib portion 76, which are connected to and / or in contact with the pressure wall 40 at a contact area 48 corresponding to the position where the pressure wall 40 contacts the partition wall 30. The first branch rib portion 75 and the second branch rib portion 76 can extend from the contact area 48 toward the outer wall 60 by branching at an angle α relative to the extension direction of the partition wall 30. In this way, force can be directly distributed from the contact area 48 onto the branch portions 75 and 76. Figure 4C As shown, the tensile stress applied in the upper edge 32 of the partition wall 30 is reduced.

[0096] As described above, the battery pack housing 10 can be cast. A plurality of reinforcing ribs 70 can be integrally formed with the pressure wall 40 and the outer wall 60 to form the battery pack housing 10.

[0097] In addition, a battery system and a vehicle including the battery pack 100 according to the above embodiments can be provided.

[0098] In short, regarding Figures 3A-3D and Figures 4A-4C An embodiment of the battery pack 100 is described, which reduces the tensile stress occurring in the upper edge 32 (i.e., critical region 34) of the partition wall 30 to improve the stress resistance and / or prevent crack formation of the battery pack 100.

[0099] Description of some figure labels

[0100] 100 battery pack

[0101] 10 Battery pack casing

[0102] 12. Capacity

[0103] 14 Bottom section

[0104] 20 battery cells stacked

[0105] 22 battery cells

[0106] 24 End portion

[0107] 30 partition walls

[0108] 32 Upper edge

[0109] 34 Critical Region

[0110] 36 Stress Reduction Zone

[0111] 40 Pressure Wall

[0112] 42 Upper edge

[0113] 44 First side

[0114] 46 Second side

[0115] 48 Contact Area

[0116] δd displacement

[0117] Hp Total pressure wall height

[0118] 50. Reinforced Structure

[0119] 60 outer wall

[0120] Ho Total external wall height

[0121] 70 Reinforcing Ribs

[0122] 71 Incision

[0123] 72 Reinforced protrusions

[0124] 73 Contact Part

[0125] 74 Uncovered areas

[0126] 75 First branch rib section

[0127] 76 Second branch rib section

[0128] 77 Descending slope

[0129] R1 First Zone (Gentle Slope)

[0130] R2 Second Zone (Steeper Slope)

[0131] α angle

[0132] F force

[0133] F1's leading player

[0134] F2 Second Main Force

[0135] Hc1 First contact height

[0136] Hc2 Second Contact Height

[0137] Hc (local) height

[0138] H (height direction)

Claims

1. A battery pack, comprising: The battery pack housing has multiple receiving spaces, and multiple battery cells are stacked and arranged in the corresponding receiving spaces; A partition wall separates adjacent battery cells in the battery cell stack from each other. A pressure wall having a first side that contacts the end portion of the battery cell stack and is connected to or integrally formed with the partition wall; as well as A reinforcing structure is provided to reinforce the partition wall, the reinforcing structure being located on a second side of the pressure wall opposite to the first side, the reinforcing structure comprising: The outer wall, spaced apart from and extending parallel to the pressure wall; and Multiple reinforcing ribs are provided between the pressure wall and the outer wall, with the reinforcing ribs contacting the outer wall and the pressure wall from the bottom portion along the height direction. The reinforcing rib has a first contact height that contacts the pressure wall and a second contact height that contacts the outer wall, wherein the second contact height is less than the total pressure wall height to the upper edge of the pressure wall.

2. The battery pack according to claim 1, wherein, The first contact height and the second contact height are less than 90% of the total pressure wall height.

3. The battery pack according to claim 1, wherein, The reinforcing rib contacts the pressure wall at the first contact height in the contact area, the contact area corresponding to the position where the pressure wall contacts the partition wall.

4. The battery pack according to claim 3, wherein, The reinforcing rib has a cutout that extends from the upper edge of the pressure wall to the first contact height in a direction opposite to the height direction at the portion of the pressure wall where the material of the reinforcing rib does not contact the pressure wall.

5. The battery pack according to claim 4, wherein, The cut is configured such that the force exerted on the pressure wall by the stack of battery cells is divided into two highly separated main forces in the partition wall.

6. The battery pack according to claim 4, wherein, The cut is the portion of the reinforcing rib that has been removed.

7. The battery pack according to claim 4, wherein, The reinforcing rib includes a reinforcing protrusion that extends in the height direction and contacts the pressure wall relative to the cut. The reinforcing protrusion is positioned by laterally shifting from the contact area corresponding to the position where the pressure wall contacts the partition wall.

8. The battery pack of claim 1, wherein the outer wall has a total outer wall height that is less than the total pressure wall height of the pressure wall.

9. The battery pack according to claim 8, wherein, The total height of the outer wall corresponds to the second contact height.

10. The battery pack according to claim 8, wherein, The local height of the reinforcing rib decreases continuously from the first contact height toward the second contact height of the outer wall.

11. The battery pack of claim 10, wherein the descending slope of the reinforcing rib is gentler in a first region near the pressure wall than in a second region near the outer wall.

12. The battery pack of claim 8, wherein the reinforcing rib includes a first branch rib portion and a second branch rib portion, the first branch rib portion and the second branch rib portion being connected to the pressure wall at a contact area corresponding to the position where the pressure wall contacts the partition wall, and extending from the contact area toward the outer wall by branching at an angle relative to the extending direction of the partition wall.

13. The battery pack according to claim 1, wherein, The battery pack casing is a casting.

14. The battery pack according to claim 1, wherein, The plurality of reinforcing ribs are integrally formed with the pressure wall and the outer wall.

15. A battery system comprising a battery pack according to any one of claims 1 to 14.

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