Battery pack

Abstract

A battery pack is disclosed. A battery pack according to one embodiment of the present invention may comprise: a case in which an internal space is provided and which has a pack cover; the battery cell is positioned in the shell; a partition wall that partitions an internal space of the housing; an adhesive member provided on the partition wall; and a bolt having a head attached to the adhesive member and a main body passing through the battery pack cover.

Description

Technical Field

[0001] This disclosure relates to battery packs.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0070922, filed in Korea on May 30, 2024, the disclosure of which is incorporated herein by reference. Background Technology

[0003] With the surge in demand for portable electronic devices such as smartphones, tablets, and smartwatches, and the increasing popularity of electric vehicles, research is actively underway on batteries installed in these vehicles, particularly rechargeable batteries that allow for repeated charging and discharging.

[0004] Currently, commercially available rechargeable batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium rechargeable batteries. Among these batteries, lithium rechargeable batteries have almost no memory effect or no memory effect at all. Therefore, due to their advantages of being able to be recharged at any convenient time, having a very low self-discharge rate, and high energy density, they have received more attention than nickel-based rechargeable batteries.

[0005] Lithium-ion secondary batteries mainly consist of lithium-based oxides and carbon materials used as positive and negative electrode active materials, respectively. A lithium-ion secondary battery includes: an electrode assembly comprising a positive electrode plate and a negative electrode plate coated with positive and negative electrode active materials, respectively, with a separator inserted between the positive and negative electrode plates; and a sealed package or battery casing that together houses the electrode assembly and the electrolyte solution.

[0006] Generally, based on the shape of the battery casing, lithium secondary batteries can be divided into can-type secondary batteries, which include the electrode assembly in a metal can, and bag-type secondary batteries, which include the electrode assembly in a bag of aluminum laminates.

[0007] Recently, rechargeable batteries have been widely used in medium to large-sized devices such as electric vehicles and energy storage systems (ESS), as well as in smaller devices such as portable electronic devices, for powering and storing energy. Multiple rechargeable batteries can be electrically connected and stored inside a module housing to form a battery module. Each rechargeable battery included in a battery module can then be referred to as a battery cell. Furthermore, multiple battery modules can be connected to each other to form a battery pack.

[0008] However, if a battery pack includes multiple battery modules, and each battery module includes multiple battery cells, as described above, the battery pack may be susceptible to thermal cascading effects between battery modules or battery cells. For example, if an event such as thermal runaway occurs within one battery module, it is necessary to prevent the thermal runaway from propagating to other battery modules or other battery cells. If the propagation of thermal runaway between battery modules or battery cells is not properly prevented, an event occurring in a particular battery module or battery cell may cause a thermal cascading effect in other battery modules or battery cells, which could lead to an explosion or fire or escalate its scale.

[0009] Specifically, when an event such as thermal runaway occurs in a battery module, gas or flame may be randomly emitted to the outside. If the emission of gas or flame is not properly controlled, it may be emitted towards other battery modules, potentially causing a thermal cascade in those modules. In particular, module terminals may be located on the front side of the battery module, and there may be configurations such as module busbars for electrical connection to other battery modules or battery packs. Therefore, if a flame is emitted to the front side of a battery module, the module terminals may be damaged, and a short circuit may occur within the battery pack. Furthermore, since other battery modules may be located on the front side of the battery module, if a flame is emitted to the front side of a particular battery module, the emitted flame may be directed to other battery modules, potentially leading to the spread of fire between battery modules.

[0010] Failure to properly control heat transfer between battery modules or cells can lead to sudden voltage drops within the battery module or battery pack. This can cause devices equipped with battery modules or battery packs to shut down abruptly, resulting in unexpected damage. For example, if a sudden voltage drop occurs in the battery pack while an electric vehicle is in operation, there will be no time to move the electric vehicle to a safe location.

[0011] Furthermore, if a fire or explosion suddenly occurs due to a failure to properly control heat transfer between battery modules or cells, it could potentially result in injury or death to users. For example, if thermal runaway occurs in an electric vehicle, occupants may not be able to escape safely if sufficient time is not guaranteed before it develops into a full-blown fire. Summary of the Invention

[0012] Technical issues

[0013] Therefore, this disclosure aims to solve the problems of the prior art, and thus, this disclosure aims to provide a battery pack with an improved structure to properly control the emissions of flames, etc., generated inside the battery module, and a vehicle including the battery pack.

[0014] In addition, this disclosure relates to a structure that facilitates the expansion of the internal space of a battery pack in the event of a thermal event.

[0015] In addition, this disclosure relates to a structure that allows the battery pack cover to bulge easily in the event of a thermal event.

[0016] In addition, this disclosure relates to a structure that maintains a seal in the event of a thermal event.

[0017] However, the technical problems sought to be solved by this disclosure are not limited to those described above, and those skilled in the art will clearly understand from the following description other problems not mentioned herein.

[0018] Technical solution

[0019] In one aspect of this disclosure, a battery pack is provided, comprising: a housing providing an internal space and having a battery pack cover; a battery cell located inside the housing; a partition wall configured to partition the internal space of the housing; an adhesive member disposed on the partition wall; and a bolt having a head attached to the adhesive member and a body extending through the battery pack cover.

[0020] Additionally, the battery pack may include a nut located on the outside of the battery pack cover and fastened to a bolt.

[0021] Additionally, the battery pack cover can come into contact with the head.

[0022] Additionally, the head can be configured to separate from the partition wall in the event of a thermal event.

[0023] Additionally, the partition wall may have a receiving groove formed at the top, and the adhesive member may be disposed in the receiving groove.

[0024] Additionally, the head may have a through hole, and the adhesive component may be filled into the through hole.

[0025] Additionally, the battery pack may include a stop attached to the upper surface of the head and configured to cover the through-hole.

[0026] Additionally, the battery pack may include a gasket disposed between the head and the battery pack cover.

[0027] In another aspect of this disclosure, a vehicle is also provided that includes a battery pack according to this disclosure.

[0028] Beneficial effects

[0029] According to at least one embodiment of the present disclosure, when gas or flame is generated inside the battery module, the discharge of gas or flame can be appropriately controlled.

[0030] According to at least one embodiment of the present disclosure, the electrical safety of the battery pack can be improved.

[0031] According to at least one embodiment of the present disclosure, the battery pack can be kept sealed even in the event of a thermal event.

[0032] According to at least one embodiment of the present disclosure, when a thermal event occurs, the internal space of the battery pack expands, thereby preventing the battery pack from exploding. Attached Figure Description

[0033] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, serve to provide a further understanding of the technical features of the present disclosure; therefore, the present disclosure is not to be construed as limited to the drawings.

[0034] Figure 1 This is a diagram illustrating a battery pack according to an embodiment of the present disclosure.

[0035] Figure 2 This shows that some of the components have been disassembled. Figure 1 A diagram of the battery pack.

[0036] Figure 3 It is shown Figure 2 A diagram of the battery module.

[0037] Figure 4 This shows that some of the components have been disassembled. Figure 3 A diagram of the battery module.

[0038] Figure 5 It is shown Figure 2 A diagram of some components of the battery pack.

[0039] Figure 6 It is along Figure 1 A partial sectional view taken by the cutting line A-A'.

[0040] Figure 7 It is along Figure 6 The sectional view taken by the cutting line B-B'.

[0041] Figure 8 It is along Figure 1 A partial sectional view taken by the cutting line A-A'.

[0042] Figure 9 This shows what happens when a thermal event occurs. Figure 8 A graph showing the changes.

[0043] Figure 10 It is according to the modified implementation method along Figure 1 A partial sectional view taken by the cutting line A-A'.

[0044] Figure 11 This shows what happens when a thermal event occurs. Figure 10 A graph showing the changes. Detailed Implementation

[0045] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Before the description, it should be understood that the terminology used in the specification and appended claims should not be construed as limited to its general and dictionary meanings, but rather interpreted according to the meanings and concepts corresponding to the technical aspects of the present disclosure, based on the principle of allowing the inventors to appropriately define the terminology for the best interpretation.

[0046] Therefore, the description presented herein is merely a preferred example for illustrative purposes only and is not intended to limit the scope of this disclosure. It should be understood that other equivalents and modifications may be made thereto without departing from the scope of this disclosure.

[0047] Figure 1 This is a diagram illustrating a battery pack according to an embodiment of the present disclosure. Figure 2 This shows that some of the components have been disassembled. Figure 1 A diagram of the battery pack.

[0048] Reference Figure 1 and Figure 2 The battery pack according to embodiments of the present disclosure may include a housing 100, battery cells, partition walls 300, adhesive members 302, and bolts 400. The housing 100 may include a base plate 110, side walls 120, and a battery pack cover 150. The base plate 110 may have a rectangular shape. The base plate 110 may have a flat shape. The base plate 110 may form the exterior of the battery pack. The base plate 110 may provide internal space for the battery pack.

[0049] Sidewall 120 can be mounted, fastened, connected, secured, or attached to the upper surface of base plate 110. Sidewall 120 can consist of four parts. Sidewall 120 can be arranged along the perimeter of base plate 110. Sidewall 120 can form the appearance of the battery pack. Sidewall 120 can provide internal space.

[0050] The battery pack cover 150 can be in the shape of a rectangular plate. The battery pack cover 150 can be in the shape of a flat plate. The battery pack cover 150 can form the exterior of the battery pack. The battery pack cover 150 can cover the internal space of the battery pack.

[0051] Battery cell 220 can refer to a secondary battery. Specifically, battery cell 220 can be a pouch-type secondary battery. However, the shape of battery cell 220 is not limited to a pouch shape and can have various shapes such as cylindrical or cuboid. Multiple battery cells 220 can be provided.

[0052] The partition wall 300 may include a first partition wall 310 and a second partition wall 320. Multiple partition walls 300 may be provided. The partition walls 300 may be mounted, fastened, fixed, connected, or attached to the upper surface of the base plate 110. The partition walls 300 may divide the internal space of the battery pack. The battery cells 220 may be located within the spaces divided by the partition walls 300.

[0053] The adhesive member 302 may be disposed on the partition wall 300. Furthermore, the adhesive member 302 may be located at the top of the partition wall 300. The adhesive member 302 may be configured to melt upon exposure to high temperatures in the event of a thermal event.

[0054] Bolt 400 may have a head 410 and a body 430. The head 410 may be attached to an adhesive member 302. The head 410 may have a rectangular plate shape. Because the head 410 has a rectangular shape, the engagement area with the partition wall 300 can be increased. The head 410 can be fixed, connected, attached, or mounted to the partition wall 300 via the adhesive member 302. The body 430 may protrude upwards from the head 410 or in the +Z axis direction. The head 410 and the body 430 may be integrally formed. The body 430 may have threads. Additionally, the body 430 may penetrate the battery pack cover 150.

[0055] According to this configuration, the thermal safety of the battery pack can be improved. When a thermal event occurs from the battery cell 220, exhaust gas g can be released. As a result, the pressure inside the battery pack may increase sharply. At this time, the adhesive member 302 may melt due to the temperature of the exhaust gas g. As a result, the bolt 400 and the partition wall 300 can be separated. In addition, when the battery pack cover 150 expands outward, the space inside the battery pack can be expanded. As a result, the battery pack explosion can be prevented.

[0056] Reference Figure 1 and Figure 2 The battery pack according to embodiments of the present disclosure may include a nut 152. The nut 152 may be located on the outside of the battery pack cover 150. Furthermore, the nut 152 may be fastened with a bolt 400. The nut 152 may be threaded onto the body 430. The battery pack cover 150 may have a fastening hole 151. The body 430 may pass through the fastening hole 151. Additionally, the nut 152 may be located on the battery pack cover 150 and connected to the body 430. The nut 152 may seal the fastening hole 151.

[0057] According to this configuration, the thermal safety of the battery pack can be improved. Even if the bolt 400 and the partition wall 300 separate in the event of a thermal event, the fastening hole 151 can remain sealed due to the connection between the nut 152 and the body 430. Therefore, high-temperature gases or flames generated inside the battery pack can be prevented from escaping to the outside.

[0058] Furthermore, according to this configuration of the present disclosure, oxygen from outside the battery pack can be prevented from flowing in through the fastening hole 151. Therefore, thermal events can be prevented from propagating inside the battery pack.

[0059] Reference Figure 1 and Figure 2 The battery pack according to embodiments of the present disclosure may include a plurality of bolts 400. The plurality of bolts 400 may be arranged along the length of the partition wall 300. The first partition wall 310 may extend along a left-right direction or a Y-axis direction. The second partition wall 320 may extend along a front-back direction or an X-axis direction. The plurality of bolts 400 may be arranged along the length of the first partition wall 310 or the length of the second partition wall 320.

[0060] According to this configuration, the thermal safety of the battery pack can be improved. Since multiple bolts 400 are connected along the partition wall 300, the battery pack cover 150 can be stably connected. Furthermore, in the event of a thermal event, the battery pack cover 150 can expand as a whole.

[0061] Reference Figure 1 and Figure 2 The battery pack according to embodiments of the present disclosure may include an exhaust device 500. The exhaust device 500 may be mounted on a side wall 120. For example, the exhaust device 500 may be mounted on the front side side wall 120. For example, the exhaust device 500 may be a valve. The exhaust device 500 may open when the pressure inside the housing 100 increases to release gas. Additionally, the exhaust device 500 may prevent external air from flowing into the housing 100. Multiple exhaust devices 500 may be provided.

[0062] According to this configuration, the thermal safety of the battery pack can be improved. When a thermal event occurs from the battery cell 220, the pressure inside the battery pack may increase rapidly. Due to the separation of the bolt 400 and the partition wall 300, the battery pack cover 150 expands outward, and the exhaust gas g is discharged to the outside through the exhaust device 500, thereby preventing the battery pack from exploding.

[0063] Figure 3 It is shown Figure 2 The diagram shows the battery module 200. Figure 4 This shows that some of the components have been disassembled. Figure 3 The diagram shows the battery module 200. (Refer to...) Figures 1 to 4 According to embodiments of the present disclosure, a battery pack may include a plurality of battery modules 200. A battery module 200 may include a module housing 210, a plurality of battery cells 220, a gasket 250, a busbar frame assembly 230, and an end cap 240.

[0064] The module housing 210 may have a cuboid shape. The module housing 210 may also be referred to as a frame 210. The module housing 210 may provide space therein. The module housing 210 may have a top plate, a bottom plate, and a pair of side plates. Additionally, the module housing 210 may have an open front and rear surface. The housing 100 may have a vent 211 in the top plate. The vent 211 allows communication between the interior and exterior of the module housing 210.

[0065] Battery cells 220 can be housed inside module housing 210. Multiple battery cells 220 can be stacked along the front-to-back direction or the X-axis direction. Each battery cell 220 may include a receiving portion 221 for accommodating electrode assemblies, a first sealing portion 222 protruding left and right from the receiving portion 221, and a second sealing portion 223 protruding upward from the receiving portion 221. Additionally, each battery cell 220 may include electrode leads 224 protruding left and right from the first sealing portion 222, respectively. Each battery cell 220 can extend along the left-to-right direction or the Y-axis direction. Electrode leads 121 can protrude left and right from each battery cell 220.

[0066] The pad 250 can be disposed between a plurality of battery cells 220. The pad 250 can be disposed between at least some of the battery cells 220 and / or at the periphery of the stack. For example, the pad 250 can be configured to be disposed between every four battery cells 220 stacked in the front-to-back direction.

[0067] The liner 250 may contain an elastic material to absorb the expansion of the battery cell 220. For example, the liner 250 may contain a foam material such as polyurethane. Alternatively, the liner 250 may contain a material capable of blocking heat or flame. For example, the liner 250 may contain a heat-insulating or flame-retardant material such as silicone or mica.

[0068] The busbar frame assembly 230 can be respectively disposed on the left and right sides of the plurality of battery cells 220. The busbar frame assembly 230 can be electrically connected to the electrode leads 121 of the plurality of battery cells 220.

[0069] A pair of end caps 240 can be connected to the left and right sides of the module housing 210, respectively. The pair of end caps 240 can cover the front and rear sides of the module housing 210. The end caps 240 can have a rectangular shape.

[0070] The battery module 200 can be mounted, fastened, connected, fixed, or attached to the upper surface of the base plate 110. In the event of a thermal event from the battery module 200, exhaust gas g can be discharged through the vent 211. The vent 211 can face the inner surface of the battery pack cover 150. The exhaust gas g discharged through the vent 211 can push the battery pack cover 150 outwards, upwards, or in the Z-axis direction.

[0071] The battery module 200 can be located in a space separated by the partition wall 300. In addition, the partition wall 300 can face at least one side of the battery module 200.

[0072] Figure 5 It is shown Figure 2 A diagram of some components of the battery pack. Figure 6 It is along Figure 1 A partial sectional view taken by the cutting line A-A'. Figure 7 It is along Figure 6 The sectional view taken by the cutting line B-B'. Figure 8 It is along Figure 1 A partial sectional view taken by the cutting line A-A'.

[0073] Reference Figures 5 to 8 According to the embodiments of this disclosure, the battery pack cover 150 can contact the upper surface of the head 410. The head 410 may also include a connecting portion 420. The connecting portion 420 may be formed at the periphery of the body 430. The connecting portion 420 can improve the rigidity of the portion connecting the head 410 and the body 430. The battery pack cover 150 can be fixed, connected, fastened, or installed between the head 410 and the nut 152. The battery pack cover 150 can be in close contact with the head 410 or the nut 152. In addition, the battery pack cover 150 can be in close contact with the connecting portion 420.

[0074] According to this configuration, the thermal stability of the battery pack can be improved. The battery pack cover 150 can be stably attached to the partition wall 300, and the fastening hole 151 can be sealed.

[0075] Reference Figures 5 to 8 According to embodiments of the present disclosure, the partition wall 300 of the battery pack may have a receiving groove 301 at its top end. The receiving groove 301 may be configured to have a depth in the downward direction or the Z-axis direction. Furthermore, an adhesive member 302 may be provided in the receiving groove 301. For example, the receiving groove 301 may have a depth of approximately 1 mm. Additionally, the receiving groove 301 may also have a shape corresponding to the shape of the head 410. Furthermore, the head 410 may be received in the receiving groove 301.

[0076] According to this configuration, the assembly tolerance of the battery pack can be reduced. Due to the receiving groove 301, the amount of adhesive coating on the bonding member 302 can be precisely controlled. This reduces the height deviation of each bolt 400 after it has been attached to the partition wall 300. Furthermore, by attaching the battery pack cover 150 to the bolts 400, the assembly tolerance of the battery pack can be reduced.

[0077] Reference Figures 5 to 8The head 410 of the battery pack according to an embodiment of the present disclosure may have a through hole 411. Furthermore, an adhesive member 302 may be filled in the through hole 411. Multiple through holes 411 may be provided. Additionally, multiple adhesive members 302 may each be filled in one of the through holes 411.

[0078] According to this configuration of the present disclosure, since the adhesive member 302 fills the through hole 411, the bolt 400 can be more securely attached to the partition wall 300. Thus, even if vibration or impact is applied to the battery pack, the battery pack cover 150 and the partition wall 300 can remain stably connected.

[0079] Reference Figures 5 to 8 The battery pack according to embodiments of the present disclosure may further include a stop member 412. The stop member 412 may be attached, coupled, or fixed to the upper surface of the head 410. The stop member 412 may have a thin sheet shape. For example, the stop member 412 may be a strip. The stop member 412 may cover the through hole 411. Furthermore, multiple stops 412 may be provided. Additionally, the stop member 412 may cover multiple through holes 411.

[0080] According to this configuration, the assembly tolerance of the battery pack can be reduced. The stop 412 can limit the maximum amount of adhesive member 302 filling the through hole 411. The stop 412 can prevent the adhesive member 302 from overflowing the through hole 411. Therefore, the amount of adhesive member 302 applied can be precisely controlled. Thus, after attaching the plurality of bolts 400 to the partition wall 300, the height deviation of each bolt 400 can be reduced. Furthermore, by attaching the battery pack cover 150 to the plurality of bolts 400, the assembly tolerance of the battery pack can be reduced.

[0081] Furthermore, according to this configuration of the present disclosure, the battery pack cover 150 and the bolts 400 can be securely fastened. The stop 412 prevents the adhesive member 302 from overfilling the through hole 411, allowing the battery pack cover 150 to maintain a stable and tight contact with the head 410.

[0082] Figure 9 This shows what happens when a thermal event occurs. Figure 8 A graph showing the changes. (Refer to...) Figure 8 and Figure 9 According to embodiments of the present disclosure, the head 410 of the battery pack can be configured to separate from the partition wall 300 in the event of a thermal event. In the event of a thermal event, the adhesive member 302 can melt due to high-temperature gases. Therefore, the head 410 can separate from the partition wall 300. Furthermore, the battery pack cover 150 can expand upwards, outwards, or in the +Z axis direction. Even if the battery pack cover 150 expands, the sealing of the fastening hole 151 can be maintained.

[0083] Figure 10 It is according to the modified implementation method along Figure 1 A partial sectional view taken by the cutting line A-A'. Figure 11 This shows what happens when a thermal event occurs. Figure 10 A graph showing the changes. (Refer to...) Figure 10 and Figure 11 The battery pack according to embodiments of this disclosure may further include a gasket 160. The gasket 160 may be disposed between the head 410 and the battery pack cover 150. The gasket 160 may comprise a highly ductile metal material. The gasket 160 may be compressibly deformable between the head 410 and the battery pack cover 150. Additionally, the gasket 160 may provide a seal between the battery pack cover 150 and the head 410.

[0084] According to this configuration disclosed, the thermal safety of the battery pack can be improved by sealing the battery pack cover 150 and the head 410.

[0085] Furthermore, this configuration according to the present disclosure can reduce the assembly tolerance of the battery pack. Due to the adhesive member 302, after the plurality of bolts 400 are attached to the partition wall 300, a height deviation of each bolt 400 may occur. At this time, the gasket 160 is located between the battery pack cover 150 and the head 410, so the battery pack cover 150 can be stably fastened, connected or fixed to the partition wall 300.

[0086] In addition to the battery module, the battery pack according to this disclosure may also include various components, such as components of a battery pack known at the time of filing of this application (such as BMS, busbars, relays, current sensors, etc.).

[0087] The battery pack according to this disclosure can be used in vehicles such as electric vehicles or hybrid vehicles. That is, a vehicle according to this disclosure can include the battery pack described above. In addition to the battery pack, a vehicle according to this disclosure may also include various other components included in the vehicle. For example, a vehicle according to this disclosure may also include a body, a motor, and control devices such as an ECU (electronic control unit).

[0088] This disclosure has been described in detail. However, it should be understood that while the detailed description and specific examples indicate preferred embodiments of this disclosure, they are given by way of illustration only, as various variations and modifications within the scope of this disclosure will become apparent to those skilled in the art based on this detailed description.

Claims

1. A battery pack, the battery pack comprising: A housing that provides internal space and has a battery pack cover; Battery cell, wherein the battery cell is located inside the housing; A partition wall, the partition wall being configured to separate the internal space of the housing; An adhesive component, wherein the adhesive component is disposed on the partition wall; as well as A bolt having a head that attaches to the adhesive member and a body that extends through the battery pack cover.

2. The battery pack according to claim 1, further comprising: A nut, located on the outside of the battery pack cover and fastened to the bolt.

3. The battery pack according to claim 1, in, The battery pack cover contacts the head.

4. The battery pack according to claim 1, in, The head is configured to separate from the partition wall in the event of a thermal event.

5. The battery pack according to claim 1, in, The partition wall has a receiving groove formed at the top, and The adhesive component is disposed in the receiving groove.

6. The battery pack according to claim 1, in, The head has a through hole, and The adhesive component fills the through hole.

7. The battery pack according to claim 6, further comprising: A stop member is attached to the upper surface of the head and configured to cover the through hole.

8. The battery pack according to claim 1, further comprising: A gasket is disposed between the head and the battery pack cover.

9. A vehicle comprising a battery pack according to any one of claims 1 to 8.

Images