Battery pack

Abstract

According to an example embodiment, a battery pack is provided. The battery pack includes a battery pack housing including a base plate and first and second side walls perpendicular to the base plate, and first and second battery cell assemblies on the base plate, wherein each of the first and second battery cell assemblies includes a plurality of battery cells arranged in a first direction parallel to a mounting surface of the base plate, and the first side wall on a first inner surface facing the first battery cell assembly includes a plurality of first dispersion structures arranged in the first direction.

Description

Technical Field

[0001] This disclosure relates to a battery pack. This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0130485, filed on September 26, 2024, the entire contents of which are incorporated herein by reference. Background Technology

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various types of wireless devices, such as mobile phones, laptops, and cordless vacuum cleaners. Recently, as the manufacturing cost per unit capacity of secondary batteries has decreased dramatically due to improvements in energy density and economies of scale, and as the driving range of battery electric vehicles (BEVs) has increased to the same level as that of fuel cell vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility tools.

[0003] The development trend of secondary battery technology for transportation vehicles is towards increased energy density and safety. The safety of secondary batteries used in transportation vehicles is directly related to passenger lives and is therefore extremely important. The safety of secondary batteries can be achieved through mechanical robustness, reliable electrical insulation, and delays in heat transfer during thermal runaway events. Summary of the Invention

[0004] Technical issues

[0005] This disclosure aims to provide a battery pack with improved safety.

[0006] Technical solution

[0007] Embodiments of this disclosure provide a battery pack. The battery pack includes: a battery pack housing, the battery pack housing including a substrate and a first sidewall and a second sidewall perpendicular to the substrate; and a first battery cell assembly and a second battery cell assembly, the first battery cell assembly and the second battery cell assembly being disposed on the substrate and each including a plurality of battery cells arranged along a first direction parallel to a mounting surface of the substrate, wherein the first sidewall includes a plurality of first dispersed structures disposed on a first inner surface facing the first battery cell assembly and arranged along the first direction.

[0008] Each of the plurality of first dispersion structures may include a circular surface.

[0009] Each of the plurality of first dispersion structures may include a patterned surface.

[0010] Each of the plurality of first dispersion structures may have a columnar shape, the columnar shape including a circular side surface with a plurality of grooves.

[0011] Each of the plurality of grooves may extend in a direction perpendicular to the mounting surface.

[0012] Each of the plurality of first dispersed structures may include a plurality of grooves extending in directions that intersect each other.

[0013] The second sidewall may include a plurality of second dispersed structures disposed on the second inner side facing the second battery cell assembly and arranged along the first direction.

[0014] The battery pack housing may further include a third sidewall and a fourth sidewall perpendicular to the substrate, and the third inner surface of the third sidewall and the fourth inner surface of the fourth sidewall are flat.

[0015] An embodiment provides a battery pack. The battery pack includes: a battery pack housing, the battery pack housing including a substrate and a first sidewall and a second sidewall perpendicular to the substrate; and a first battery cell assembly and a second battery cell assembly, the first battery cell assembly and the second battery cell assembly being disposed on the substrate and each including a plurality of battery cells arranged along a first direction parallel to a mounting surface of the substrate. The first sidewall includes a first inner surface facing the first battery cell assembly and being knurled.

[0016] The first inner surface may include a plurality of grooves formed on a plane.

[0017] Each of the plurality of grooves may extend in a direction perpendicular to the mounting surface.

[0018] The first inner surface may include a plurality of grooves formed on a plane and extending in directions that intersect each other.

[0019] The second sidewall may include a second inner surface facing the second battery cell assembly and being knurled.

[0020] Beneficial effects

[0021] According to embodiments of this disclosure, the sidewalls of the battery pack include a dispersion structure. The dispersion structure of the sidewalls can uniformly disperse gases and excretions emitted from individual battery cells undergoing thermal runaway events within the battery cell assembly. Therefore, damage caused by the emitted gases and excretions is dispersed, thereby delaying heat propagation.

[0022] The effects achievable by the embodiments of this disclosure are not limited to those described above. Those skilled in the art will clearly derive and understand other effects not described herein based on the following description. In other words, those skilled in the art can derive unexpected effects achieved in implementing the embodiments of this disclosure. Attached Figure Description

[0023] Figure 1 This is a plan view of the battery pack according to the implementation method.

[0024] Figure 2 The dispersed structure of the sidewall of the battery pack housing according to an embodiment is shown.

[0025] Figure 3 The dispersed structure of the sidewall of the battery pack housing according to other embodiments is shown.

[0026] Figure 4 This is a plan view of the battery pack according to the implementation method. Detailed Implementation

[0027] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before describing embodiments of the present disclosure, the terms or expressions used in this specification and claims should not be construed as limited to their commonly understood or defined meanings in common dictionaries, and should be understood according to the meanings and concepts corresponding to the present disclosure, based on the inventors' ability to appropriately define the terms or expressions to best interpret the principles of the present disclosure.

[0028] Therefore, the embodiments described herein and the configurations shown in the accompanying drawings are merely examples of this disclosure and do not reflect all the technical ideas of this disclosure. It should be understood that various equivalents and modifications have been made to replace the configurations as of the date of filing of this application.

[0029] When it is determined that a well-known configuration or function related to the description of this disclosure would obscure the subject matter of this disclosure due to unnecessary details, the well-known configuration or function related to the description of this disclosure will not be described in detail.

[0030] Because the embodiments of this disclosure are provided to explain the disclosure more fully to those skilled in the art, the shapes, dimensions, etc. of the components shown in the drawings may be enlarged, omitted, or illustrated schematically for clarity. Therefore, it should not be understood that the dimensions or proportions of the components fully reflect their actual dimensions or proportions.

[0031] (First and Second Embodiments)

[0032] Figure 1 This is a plan view of the battery pack 100 according to the embodiment.

[0033] Figure 2 The dispersed structures 112D and 113D of the sidewalls 112 and 113 of the battery pack housing 110 according to an embodiment are shown.

[0034] refer to Figure 1 and Figure 2The battery pack 100 may include a battery pack housing 110 and multiple battery cell assemblies 120_1 and 120_2.

[0035] The battery pack housing 110 provides space for mounting battery cell assemblies 120_1 and 120_2. The battery pack housing 110 may include a base plate 111 and sidewalls 112, 113, 114 and 115.

[0036] In the following text, the two directions substantially parallel to the mounting surface of substrate 111 are defined as the X-axis direction and the Y-axis direction. The mounting surface of substrate 111 may face multiple battery cell assemblies 120_1 and 120_2. In the following text, the direction substantially perpendicular to the mounting surface of substrate 111 is defined as the Z-axis direction. The X-axis direction, Y-axis direction, and Z-axis direction may be substantially perpendicular to each other. Unless otherwise stated, this definition of direction will apply to the following figures.

[0037] The substrate 111 may include multiple plates formed by an extrusion process. The substrate 111 may include a central beam 116. The central beam 116 may extend along the X-axis direction. The central beam 116 may be formed by an extrusion process of one of the multiple plates of the substrate 111, or it may be soldered to the substrate 111.

[0038] The substrate 111 may include multiple cooling channels. Each of the multiple cooling channels may extend along the X-axis. The multiple cooling channels allow coolant to flow through these cooling channels, and thus multiple battery cell assemblies 120_1 and 120_2 can be cooled.

[0039] Sidewalls 112 and 113 can be provided by an extrusion process. Sidewalls 112 and 113 can be joined to substrate 111 by friction stir welding or the like. Sidewalls 112 and 113 can extend along the X-axis. A central beam 116 can be inserted between sidewalls 112 and 113.

[0040] Sidewall 112 may include an inner surface 112IS facing the battery cell assembly 120_1. Sidewall 113 may include an inner surface 113IS facing the battery cell assembly 120_2.

[0041] Sidewalls 114 and 115 may be located on substrate 111. Sidewalls 114 and 115 may be connected to substrate 111 by means of soldering or the like. Sidewalls 114 and 115 may also be provided by an extrusion process.

[0042] Sidewalls 112, 113, 114, and 115 may horizontally surround multiple battery cell assemblies 120_1 and 120_2. Each of sidewalls 112, 113, 114, and 115 may be substantially perpendicular to the substrate 111.

[0043] Multiple battery cell assemblies 120_1 and 120_2 may be located on the substrate 111. Battery cell assembly 120_1 may be located between the sidewall 112 and the central beam 116. Battery cell assembly 120_2 may be located between the sidewall 113 and the central beam 116. The central beam 116 may be located between battery cell assembly 120_1 and battery cell assembly 120_2.

[0044] Multiple battery cell assemblies 120_1 and 120_2 can be arranged along the X-axis and Y-axis directions. Figure 1 In this diagram, multiple battery cell assemblies 120_1 and 120_2 are arranged in a 3×2 matrix. Based on the description herein, those skilled in the art will be able to readily derive multiple battery cell assemblies 120_1 and 120_2 arranged in an M×N array (where M and N are each integers of 2 or greater).

[0045] The battery pack 100 may be of a module-less type, and each of the plurality of battery cell assemblies 120_1 and 120_2 may not include a module frame. As another example, the battery pack 100 may be of a module type, and each of the plurality of battery cell assemblies 120_1 and 120_2 may include a module frame.

[0046] Each of the plurality of battery cell assemblies 120_1 and 120_2 may include a plurality of battery cells 121, a first integrated circuit assembly 123, and a second integrated circuit assembly 125. Each of the plurality of battery cell assemblies 120_1 and 120_2 may also include a flexible flat cable (FFC) assembly connecting the first integrated circuit assembly 123 and the second integrated circuit assembly 125 to each other.

[0047] Each of the plurality of battery cells 121 may be a lithium-ion battery. Each of the plurality of battery cells 121 includes an electrode assembly, an electrolyte, and a casing. Each of the plurality of battery cells may be a cylindrical battery cell, a prismatic battery cell, or a pouch battery cell. The electrode assembly of a cylindrical battery cell is embedded in a cylindrical metal can. The electrode assembly of a prismatic battery cell is embedded in a prismatic metal can. The electrode assembly of a pouch battery cell is embedded in a pouch containing aluminum laminates.

[0048] An electrode assembly may include a positive electrode, a negative electrode, and a separator between the positive and negative electrodes. The electrode assembly may be a wound-core type electrode assembly or a stacked type electrode assembly. A wound-core type electrode assembly may include a structure in which the positive electrode, negative electrode, and separator between the positive and negative electrodes are wound together. A stacked type electrode assembly may include multiple positive electrodes and multiple negative electrodes sequentially stacked, and multiple separators between the positive and negative electrodes.

[0049] Multiple battery cells 121 can be arranged along the X-axis. Multiple battery cells 121 can form multiple groups. Each group can include one or more battery cells 121 connected in parallel. Multiple groups can be connected in series with each other. The number of groups connected in series and the number of battery cells 121 connected in parallel can be determined based on the voltage and current to be output from each of the multiple battery cell assemblies 120_1 and 120_2.

[0050] Multiple battery cells 121 may be located between a first integrated circuit assembly 123 and a second integrated circuit assembly 125. The first integrated circuit assembly 123 of each of the multiple battery cell assemblies 120_1 and 120_2 may be located on the central portion of the battery pack housing 110 (e.g., the central portion of the battery pack housing 110 in the Y-axis direction). The first integrated circuit assembly 123 of each of the multiple battery cell assemblies 120_1 and 120_2 may face the central beam 116.

[0051] The second integrated circuit assembly 125 of each of the plurality of battery cell assemblies 120_1 and 120_2 may be located in the edge portion of the battery pack housing 110 (e.g., the edge portion of the battery pack housing 110 in the Y-axis direction). The second integrated circuit assembly 125 of each battery cell assembly 120_1 may face the sidewall 112. The second integrated circuit assembly 125 of each battery cell assembly 120_2 may face the sidewall 113.

[0052] The first integrated circuit assembly 123 may include an insulating frame, an integrated circuit, a busbar, a sensing board, a sensing strip, a temperature sensor, wires, and an insulating cover.

[0053] The insulating frame may include insulating materials such as plastic. The insulating frame may cover the front side of multiple battery cells 121. The insulating frame may support integrated circuits, busbars, sensing boards, sensing strips, temperature sensors, and wires.

[0054] The busbar can be shorted to the positive leads of one or more battery cells 121 in the first group and the negative leads of one or more battery cells 121 in the last group. The busbar can be soldered to the positive leads of one or more battery cells 121 in the first group and the negative leads of one or more battery cells 121 in the last group. The voltage obtained from the multiple battery cells 121 in each of the multiple battery cell assemblies 120_1 and 120_2 can be output through the busbar. The busbar can be fixed to the insulating frame.

[0055] The integrated circuit can be mounted on an insulating frame. The positive and negative leads, soldered together, can form a node within each of the multiple battery cell assemblies 120_1 and 120_2. The integrated circuit can be configured to measure the voltage of the node.

[0056] The sensing strip may include a conductive material. The sensing strip may have a rod shape. The sensing strip may be shorted to a busbar. The sensing strip may be connected to a busbar. The voltage of the busbar can be measured through the sensing strip.

[0057] Each sensing plate may have a patch shape or a pad shape. The sensing plate may include a conductive material. The sensing plate may be shorted to the corresponding positive and negative leads of the multiple battery cells 121.

[0058] Each sensing board can be connected to an integrated circuit. The voltage of multiple nodes in each of the multiple battery cell assemblies 120_1 and 120_2 can be measured through the sensing boards.

[0059] Temperature sensors can be configured to measure the temperature at multiple points on multiple battery cell assemblies 120_1 and 120_2. The temperature sensors can be arranged along the X-axis, Y-axis, and Z-axis directions, and therefore can measure the temperature distribution within the multiple battery cell assemblies 120_1 and 120_2.

[0060] The insulating cover may include an insulating material, such as plastic. The insulating cover may be interference-fitted into an insulating frame. The insulating cover may cover the integrated circuit, busbar, sensing board, sensing strip, and temperature sensor, and thus protect the electrical components of the first integrated circuit assembly 123.

[0061] The second integrated circuit assembly 125 may include an insulating frame, an integrated circuit, a sensing board, a temperature sensor, wires, and an insulating cover. Except that the second integrated circuit assembly 125 does not include a busbar and a sensing bar, the second integrated circuit assembly 125 is substantially the same as the first integrated circuit assembly 123.

[0062] The sidewall 112 may include a plurality of dispersed structures 112D on its inner surface 112IS. The plurality of dispersed structures 112D may be arranged along the X-axis direction. According to an embodiment, each of the plurality of dispersed structures 112D may extend along the Z-axis direction.

[0063] Each of the plurality of dispersion structures 112D may include a circular surface. Each of the plurality of dispersion structures 112D may have a cylindrical shape including circular side surfaces. According to an embodiment, the cylindrical shape of each of the plurality of dispersion structures 112D may have a height in the Z-axis direction.

[0064] Each of the plurality of dispersed structures 112D may include a patterned surface. Each of the plurality of dispersed structures 112D may include a plurality of grooves. According to an embodiment, the surface of each of the plurality of dispersed structures 112D may be formed by knurling. According to an embodiment, the plurality of grooves of each of the plurality of dispersed structures 112D may each extend along the Z-axis direction. Each of the plurality of dispersed structures 112D may have a columnar shape including circular side surfaces having a plurality of grooves.

[0065] According to the embodiment, when the battery cell assembly 120_1 is designed to vent backward (i.e., vent from the second integrated circuit assembly 125), the plurality of dispersion structures 112D can uniformly disperse the gas and effluent emitted from the battery cell assembly 120_1 in the event of a thermal runaway, and thus disperse the damage caused by the emitted gas and effluent, thereby delaying heat propagation.

[0066] The sidewall 113 may include a plurality of dispersed structures 113D on its inner surface 113IS. The plurality of dispersed structures 113D may be arranged along the X-axis direction. According to an embodiment, each of the plurality of dispersed structures 113D may extend along the Z-axis direction.

[0067] Each of the plurality of dispersed structures 113D may include a circular surface. Each of the plurality of dispersed structures 113D may have a cylindrical shape including circular side surfaces. According to an embodiment, the cylindrical shape of each of the plurality of dispersed structures 113D may have a height in the Z-axis direction.

[0068] Each of the plurality of dispersed structures 113D may include a patterned surface. Each of the plurality of dispersed structures 113D may include a plurality of grooves. According to an embodiment, the surface of each of the plurality of dispersed structures 113D may be formed by knurling. According to an embodiment, the plurality of grooves of each of the plurality of dispersed structures 113D may each extend along the Z-axis direction. Each of the plurality of dispersed structures 113D may have a columnar shape including a circular side surface having a plurality of grooves.

[0069] According to the embodiment, when the battery cell assembly 120_2 is designed to vent backward (i.e., vent from the second integrated circuit assembly 125), the plurality of dispersion structures 113D can uniformly disperse the gas and effluent emitted from the battery cell assembly 120_2 in the event of a thermal runaway, and thus disperse the damage caused by the emitted gas and material, thereby delaying heat propagation.

[0070] On the other hand, since sidewalls 114 and 115 are not in the emission direction of gases and effluents from the multiple battery cell assemblies 120_1 and 120_2, the inner surface of each of sidewalls 114 and 115 may not be knurled. The inner surfaces 114IS and 115IS of sidewalls 114 and 115 may not include a dispersion structure. The inner surfaces 114IS and 115IS of each of sidewalls 114 and 115 may be flat.

[0071] The battery pack 100 may also include a battery management system (BMS). The BMS may be located between the plurality of battery cell assemblies 120_1 and 120_2 and the sidewall 114. The BMS may be configured to monitor, balance, and control the battery pack 100. Monitoring of the battery pack 100 may include measuring the voltage and current at certain nodes within the plurality of battery cell assemblies 120_1 and 120_2, and measuring the temperature at designated locations within the battery pack 100. The battery pack 100 may include measuring devices for measuring voltage, current, and temperature as described above.

[0072] Balancing the battery pack 100 is an operation to reduce the deviations between the multiple battery cell assemblies 120_1 and 120_2. Control of the battery pack 100 includes prevention of overcharging, over-discharging, and overcurrent. Through monitoring, balancing, and control, the battery pack 100 can operate under optimal conditions to prevent a reduction in the lifespan of each of the multiple battery cell assemblies 120_1 and 120_2.

[0073] The battery pack 100 may also include a venting device. The venting device may be configured to delay heat propagation by venting hot gas from the interior of the battery pack 100 to the exterior when at least one of the plurality of battery cell assemblies 120_1 and 120_2 is in a thermal runaway state.

[0074] The battery pack 100 may also include additional electronic components. Examples of additional electronic components may include cooling devices, power relay (PRA) assemblies, safety plugs, etc. Cooling devices may include cooling fans. Cooling fans circulate air within the battery pack 100 to prevent overheating of each of the multiple battery cell assemblies 120_1 and 120_2. The PRA may be configured to supply or disconnect power from the high-voltage battery to an external load (e.g., the vehicle's motor). In the event of an abnormal voltage such as a voltage surge, the PRA can disconnect the power supply to the external load (e.g., the vehicle's motor) to protect the multiple battery cell assemblies 120_1 and 120_2 and the external load (e.g., the vehicle's motor).

[0075] The battery pack 100 may also include multiple busbars configured to electrically connect battery cell assemblies 120_1 and 120_2. Battery cell assemblies 120_1 and 120_2 can be connected in series via the multiple busbars. Therefore, the battery pack 100 can be configured to output a high voltage to an external load (e.g., a vehicle's motor).

[0076] The battery pack 100 may also include a cover plate attached to the sidewalls 112, 113, 114, and 115. The cover plate may cover components inside the battery pack 100, such as battery cell assemblies 120_1 and 120_2 and electronic components. The cover plate may be secured to the battery pack 100 via a mechanical coupling device such as a fastening member.

[0077] (Second Implementation)

[0078] Figure 3 Dispersion structures 112D' and 113D' according to other embodiments are shown. Figure 3 The dispersed structures 112D' and 113D' can replace Figure 1 and Figure 2 The dispersed structures 112D and 113D.

[0079] refer to Figure 3 Each of the dispersion structures 112D' and 113D' can be processed by diamond knurling instead of straight knurling. Therefore, each of the dispersion structures 112D' and 113D' can include a circular surface. Each of the dispersion structures 112D' and 113D' can include a patterned surface. Each of the dispersion structures 112D' and 113D' can include a plurality of grooves. Each of the dispersion structures 112D' and 113D' can have a columnar shape including circular sides with a plurality of grooves. According to an embodiment, each of the dispersion structures 112D' and 113D' can include a plurality of grooves extending in an inclined direction.

[0080] (Third implementation method)

[0081] Figure 4 This is a plan view of the battery pack 100' according to the embodiment.

[0082] refer to Figure 4 The battery pack 100' may include a battery pack housing 110' and multiple battery cell assemblies 120_1 and 120_2. The multiple battery cell assemblies 120_1 and 120_2 are referenced above. Figure 1 The battery cell components described are basically the same.

[0083] Except for the sidewall 112' including the knurled inner surface 112IS' and the sidewall 113' including the knurled inner surface 113IS', the battery pack housing 110' and Figure 1 The battery pack housing 110 is substantially the same. Except for its knurled portion, the inner surfaces 112IS' and 113IS' can be substantially flat. That is, the inner surfaces 112IS' and 113IS' can be formed by performing straight-knurling or diamond-knurling on the inner surfaces of the sidewalls 112' and 113', which are flat surfaces.

[0084] The inner surface 112IS' may include a plurality of grooves formed on the plane. Similar to... Figure 2 Multiple grooves can extend along the Z-axis. Similar to... Figure 3 The inner surface 112IS' may include a plurality of grooves formed on the plane and extending in directions that intersect each other.

[0085] The inner surface 113IS' may include a plurality of grooves formed on the plane. Similar to... Figure 2 Multiple grooves can extend along the Z-axis. Similar to... Figure 3 The inner surface 113IS' may include a plurality of grooves formed on the plane and extending in directions that intersect each other.

[0086] The present disclosure has been described in more detail above with reference to the accompanying drawings and embodiments. However, the configurations shown in the drawings or the embodiments described in this specification are merely examples of the present disclosure and do not reflect all the technical ideas of the present disclosure. Therefore, it should be understood that various equivalents and modifications to these configurations will be made as of the date of filing of this application.

Claims

1. A battery pack, the battery pack comprising: A battery pack housing, the battery pack housing including a substrate and a first sidewall and a second sidewall perpendicular to the substrate; as well as A first battery cell assembly and a second battery cell assembly are disposed on the substrate and each includes a plurality of battery cells arranged along a first direction parallel to the mounting surface of the substrate. The first sidewall includes a plurality of first dispersed structures disposed on the first inner side facing the first battery cell assembly and arranged along the first direction.

2. The battery pack according to claim 1, wherein, Each of the plurality of first dispersion structures includes a circular surface.

3. The battery pack according to claim 1, wherein, Each of the plurality of first dispersion structures includes a patterned surface.

4. The battery pack according to claim 1, wherein, Each of the plurality of first dispersed structures has a columnar shape, the columnar shape including a circular side surface with a plurality of grooves.

5. The battery pack according to claim 4, wherein, Each of the plurality of grooves extends in a direction perpendicular to the mounting surface.

6. The battery pack according to claim 1, wherein, Each of the plurality of first dispersion structures includes a plurality of grooves extending in directions that intersect each other.

7. The battery pack according to claim 1, wherein, The second sidewall includes a plurality of second dispersed structures disposed on the second inner side facing the second battery cell assembly and arranged along the first direction.

8. The battery pack according to claim 1, wherein, The battery pack housing also includes a third sidewall and a fourth sidewall perpendicular to the substrate. The third inner surface of the third sidewall and the fourth inner surface of the fourth sidewall are flat.

9. A battery pack, the battery pack comprising: A battery pack housing, the battery pack housing including a substrate and a first sidewall and a second sidewall perpendicular to the substrate; as well as A first battery cell assembly and a second battery cell assembly are disposed on the substrate and each includes a plurality of battery cells arranged along a first direction parallel to the mounting surface of the substrate. The first sidewall includes a first inner surface facing the first battery cell assembly and having been knurled.

10. The battery pack according to claim 9, wherein, The first inner surface includes a plurality of grooves formed on a plane.

11. The battery pack according to claim 10, wherein, Each of the plurality of grooves extends in a direction perpendicular to the mounting surface.

12. The battery pack according to claim 9, wherein, The first inner surface includes a plurality of grooves formed on a plane and extending in directions that intersect each other.

13. The battery pack according to claim 9, wherein, The second sidewall includes a second inner surface facing the second battery cell assembly and being knurled.

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