Battery pack

Abstract

According to exemplary embodiments, a battery pack is provided. The battery pack comprises: a pack housing including a base plate and first and second sidewalls 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 sidewall is on a first inner surface facing the first battery cell assembly and includes a plurality of dispersion structures arranged in the first direction.

Description

battery pack

[0001] The present invention relates to a battery pack. The present application claims the benefit of Korean application No. 10-2024-0130485, filed on September 26, 2024, which is incorporated herein by reference in its entirety.

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

[0003] The trend in the technological development of secondary batteries for mobility is the improvement of energy density and safety. The safety of secondary batteries for mobility is critical as it is directly related to the lives of passengers. The safety of secondary batteries can be achieved through mechanical robustness, the reliability of electrical insulation, and the delay of heat transfer in the event of a thermal runaway event.

[0004] The problem that the technical concept of the present invention aims to solve is to provide a battery pack having enhanced safety.

[0005] According to exemplary embodiments of the present invention for solving the above-described problem, a battery pack is provided. The battery pack comprises: a 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 comprises a plurality of battery cells arranged in a first direction parallel to the mounting surface of the base plate, and the first side wall is on a first inner surface facing the first battery cell assembly and comprises a plurality of first dispersion structures arranged in the first direction.

[0006] Each of the above plurality of first dispersion structures includes a rounded surface.

[0007] Each of the above plurality of first dispersion structures includes a patterned surface.

[0008] Each of the above plurality of first dispersion structures has a column shape including a rounded side including a plurality of grooves.

[0009] Each of the above plurality of grooves extends in a direction perpendicular to the mounting surface.

[0010] Each of the above plurality of first dispersion structures includes a plurality of grooves extending in directions intersecting each other.

[0011] The second sidewall is located on the second inner side facing the second battery cell assembly and includes a plurality of second dispersion structures arranged in the first direction.

[0012] The above pack housing further includes third and fourth side walls perpendicular to the base plate, and the third inner surface of the third side wall and the fourth inner surface of the fourth side wall are each flat.

[0013] According to exemplary embodiments, a battery pack is provided. The battery pack comprises a 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 comprises a plurality of battery cells arranged in a first direction parallel to a mounting surface of the base plate, and the first side wall comprises a first inner surface knurled facing the first battery cell assembly.

[0014] The first inner surface includes a plurality of grooves formed on a flat surface.

[0015] Each of the above plurality of grooves extends in a direction perpendicular to the mounting surface.

[0016] The first inner surface includes a plurality of grooves formed on a plane and extending in directions intersecting each other.

[0017] The second side wall includes a second inner surface that faces the second battery cell assembly and is knurled.

[0018] According to exemplary embodiments of the present invention, the sidewalls of a battery pack include dispersion structures. The dispersion structures of the sidewalls can evenly disperse gases and discharges emitted from battery cell assemblies in a thermal runaway event, and accordingly, damage caused by gases and discharges is dispersed, thereby delaying thermal propagation.

[0019] The effects obtainable from the exemplary embodiments of the present invention are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0020] FIG. 1 is a plan view showing a battery pack according to exemplary embodiments.

[0021] FIG. 2 shows dispersion structures of the side walls of a pack housing according to exemplary embodiments.

[0022] FIG. 3 shows dispersion structures of the side walls of a pack housing according to other exemplary embodiments.

[0023] FIG. 4 is a plan view showing a battery pack according to exemplary embodiments.

[0024] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe his invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention.

[0025] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0026] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0027] Since embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, the shapes and sizes of the components in the drawings may be exaggerated, omitted, or schematically depicted for clearer explanation. Accordingly, the size or proportion of each component does not entirely reflect the actual size or proportion.

[0028]

[0029] (1st and 2nd embodiments)

[0030] FIG. 1 is a plan view showing a battery pack (100) according to exemplary embodiments.

[0031] FIG. 2 shows dispersion structures (112D, 113D) of the side walls (112, 113) of a pack housing (110) according to exemplary embodiments.

[0032] Referring to FIGS. 1 and 2, the battery pack (100) may include a pack housing (110) and a plurality of battery cell assemblies (120_1, 120_2).

[0033] The pack housing (110) may provide a space for mounting battery cell assemblies (120_1, 120_2). The pack housing (110) may include a base plate (111) and side walls (112, 113, 114, 115).

[0034] Two directions substantially parallel to the mounting surface of the base plate (111) are defined as the X direction and the Y direction. The mounting surface of the base plate (111) may face a plurality of battery cell assemblies (120_1, 120_2). A direction substantially perpendicular to the mounting surface of the base plate (111) is defined as the Z direction. Each of the X direction, Y direction, and Z direction may be substantially perpendicular to each other. Unless otherwise noted, the definitions of directions are the same for the following drawings.

[0035] The base plate (111) may include a plurality of plates formed by an extrusion process. The base plate (111) may include a center beam (116). The center beam (116) may extend in the X direction. The center beam (116) may be formed by an extrusion process of one of the plurality of plates of the base plate (111) or may be welded to the base plate (111).

[0036] The base plate (111) may include a plurality of cooling channels. Each of the plurality of cooling channels may extend in the X direction. The plurality of cooling channels may allow the flow of a coolant, thereby allowing a plurality of battery cell assemblies (120_1, 120_2) to be cooled.

[0037] The side walls (112, 113) can be provided by an extrusion process. The side walls (112, 113) can be joined to the base plate (111) by a method such as friction stir welding. The side walls (112, 113) can be extended in the X direction. A center beam (116) can be interposed between the side walls (112, 113).

[0038] The side wall (112) may include an inner surface (112IS) facing the battery cell assemblies (120_1). The side wall (113) may include an inner surface (113IS) facing the battery cell assemblies (120_2).

[0039] The side walls (114, 115) may be on the base plate (111). The side walls (114, 115) may be joined to the base plate (111) by a method such as brazing. The side walls (114, 115) may also be provided by an extrusion process.

[0040] The side walls (112, 113, 114, 115) can horizontally surround a plurality of battery cell assemblies (120_1, 120_2). Each of the side walls (112, 113, 114, 115) can be substantially perpendicular to the base plate (111).

[0041] Multiple battery cell assemblies (120_1, 120_2) may be on a base plate (111). Battery cell assemblies (120_1) may be between a side wall (112) and a center beam (116). Battery cell assemblies (120_2) may be between a side wall (113) and a center beam (116). A center beam (116) may be interposed between battery cell assemblies (120_1) and battery cell assemblies (120_2).

[0042] Multiple battery cell assemblies (120_1, 120_2) may be arranged in the X and Y directions. In FIG. 1, the multiple battery cell assemblies (120_1, 120_2) may be arranged in a 3 * 2 configuration. A person skilled in the art will be able to easily arrive at multiple battery cell assemblies (120_1, 120_2) arranged in an M * N configuration (where M and N are integers greater than or equal to 2) based on the description herein.

[0043] The battery pack (100) is of the modular type, and each of the plurality of battery cell assemblies (120_1, 120_2) may not include a module frame. As another example, the battery pack (100) may be of the modular type, and each of the plurality of battery cell assemblies (120_1, 120_2) may include a module frame.

[0044] Each of the plurality of battery cell assemblies (120_1, 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, 120_2) may further include a Flexible Flat Cable (FFC) assembly connecting the first integrated circuit assembly (123) and the second integrated circuit assembly (125) to each other.

[0045] 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 case. Each of the plurality of battery cells may be any one of a cylindrical battery cell, a prismatic battery cell, and a pouch-type battery cell. The electrode assembly of the cylindrical battery cell is embedded in a cylindrical metal can. The electrode assembly of the prismatic battery cell is embedded in a prismatic metal can. The electrode assembly of the pouch-type battery cell is embedded in a pouch case containing an aluminum laminate sheet.

[0046] The electrode assembly may include an anode, a cathode, and a separator interposed between the anode and the cathode. The electrode assembly may be either a jelly-roll type or a stack type. A jelly-roll type electrode assembly may include a wound structure of an anode, a cathode, and a separator interposed between them. A stack type electrode assembly may include a plurality of sequentially stacked anodes, a plurality of cathodes, and a plurality of separators interposed between them.

[0047] Multiple battery cells (121) may be arranged in the X direction. Multiple battery cells (121) may form multiple banks. Each of the multiple banks may include one or more battery cells (121) connected in parallel. Multiple banks may be connected in series with each other. The number of series-connected banks and the number of parallel-connected battery cells (121) may be determined according to the magnitude of the voltage and current to be output from each of the battery cell assemblies (120_1, 120_2).

[0048] There may be a plurality of battery cells (121) between the first integrated circuit assembly (123) and the second integrated circuit assembly (125). The first integrated circuit assembly (123) of each of the plurality of battery cell assemblies (120_1, 120_2) may be located at the center of the pack housing (110) (e.g., the center in the Y direction). The first integrated circuit assembly (123) of each of the plurality of battery cell assemblies (120_1, 120_2) may face the center beam (116).

[0049] A second integrated circuit assembly (125) of each of the plurality of battery cell assemblies (120_1, 120_2) may be placed at an edge portion (e.g., an edge portion in the Y direction) of the pack housing (110). A second integrated circuit assembly (125) of each of the battery cell assemblies (120_1) may face a side wall (112). A second integrated circuit assembly (125) of each of the battery cell assemblies (120_2) may face a side wall (113).

[0050] The first integrated circuit assembly (123) may include an insulating frame, an integrated circuit, bus bars, sensing plates, sensing bars, temperature sensors, wiring, and an insulating cover.

[0051] The insulating frame may include an insulating material such as plastic. The insulating frame may cover the front of a plurality of battery cells (121). The insulating frame may support an integrated circuit, bus bars, sensing plates, sensing bars, temperature sensors, and wiring.

[0052] The bus bars may be short-circuited to the positive leads of one or more battery cells (121) of the first bank and to the negative leads of one or more battery cells (121) of the last bank. The bus bars may be welded to the positive leads of one or more battery cells (121) of the first bank and to the negative leads of one or more battery cells (121) of the last bank. The resulting voltage of the multiple battery cells (121) of each of the multiple battery cell assemblies (120_1, 120_2) may be output through the bus bars. The bus bars may be fixed to an insulating frame.

[0053] The integrated circuit can be mounted on an insulating frame. Positive leads and negative leads welded to each other can form nodes within a plurality of battery cell assemblies (120_1, 120_2). The integrated circuit can be configured to measure the voltage of the nodes.

[0054] The sensing bars may include a conductive material. The sensing bars may have a rod shape. The sensing bars may be short-circuited to the bus bars. The sensing bars may be coupled to the bus bars. Through the sensing bars, the voltage of the bus bars can be measured.

[0055] Each of the plurality of sensing plates may have a patch shape or a pad shape. The plurality of sensing plates may include a conductive material. The plurality of sensing plates may be short-circuited to corresponding positive leads and negative leads of the plurality of battery cells (121).

[0056] Each of the multiple sensing plates can be connected to an integrated circuit. Through the multiple sensing plates, the voltage of each of the multiple nodes of the multiple battery cell assemblies (120_1, 120_2) can be measured.

[0057] Temperature sensors can be configured to measure the temperature at multiple points of multiple battery cell assemblies (120_1, 120_2). The temperature sensors can be arranged in the X direction, Y direction and Z direction, and accordingly, the temperature distribution within the multiple battery cell assemblies (120_1, 120_2) can be measured.

[0058] The insulating cover may include an insulating material such as plastic. The insulating cover may be fitted into an insulating frame. The insulating cover may cover an integrated circuit, bus bars, sensing plates, sensing bars, and temperature sensors, and accordingly, the electrical elements of the first integrated circuit assembly (123) may be protected.

[0059] The second integrated circuit assembly (125) may include an insulating frame, an integrated circuit, sensing plates, temperature sensors, wiring, and an insulating cover. The second integrated circuit assembly (125) is generally similar to the first integrated circuit assembly (123), except that it does not include bus bars and sensing bars.

[0060] The side wall (112) may include a plurality of dispersion structures (112D) on the inner surface (112IS) of the side wall (112). The plurality of dispersion structures (112D) may be arranged along the X direction. According to exemplary embodiments, each of the plurality of dispersion structures (112D) may extend in the Z direction.

[0061] Each of the plurality of dispersion structures (112D) may include a rounded surface. Each of the plurality of dispersion structures (112D) may have a columnar shape including a rounded side. According to exemplary embodiments, each of the columnar shapes of the plurality of dispersion structures (112D) may have a height in the Z direction.

[0062] Each of the plurality of dispersion structures (112D) may include a patterned surface. Each of the plurality of dispersion structures (112D) may include a plurality of grooves. According to exemplary embodiments, the surface of each of the plurality of dispersion structures (112D) may be formed by straight knurling. According to exemplary embodiments, each of the plurality of grooves of each of the plurality of dispersion structures (112D) may extend in the Z direction. Each of the plurality of dispersion structures (112D) may have a columnar shape including a rounded side comprising a plurality of grooves.

[0063] According to exemplary embodiments, when battery cell assemblies (120_1) are designed with rear venting (i.e., venting from the second integrated circuit assembly (125)), a plurality of dispersion structures (112D) can evenly disperse gases and discharges emitted from the battery cell assemblies (120_1) that are in a thermal runaway event, and accordingly, damage caused by gases and discharges is dispersed, so that heat propagation can be delayed.

[0064] The side wall (113) may include a plurality of dispersion structures (113D) on the inner surface (113IS) of the side wall (113). The plurality of dispersion structures (113D) may be arranged along the X direction. According to exemplary embodiments, each of the plurality of dispersion structures (113D) may extend in the Z direction.

[0065] Each of the plurality of dispersion structures (113D) may include a rounded surface. Each of the plurality of dispersion structures (113D) may have a columnar shape including a rounded side. According to exemplary embodiments, each of the columnar shapes of the plurality of dispersion structures (113D) may have a height in the Z direction.

[0066] Each of the plurality of dispersion structures (113D) may include a patterned surface. Each of the plurality of dispersion structures (113D) may include a plurality of grooves. According to exemplary embodiments, the surface of each of the plurality of dispersion structures (113D) may be formed by straight knurling. According to exemplary embodiments, each of the plurality of grooves of each of the plurality of dispersion structures (113D) may extend in the Z direction. Each of the plurality of dispersion structures (113D) may have a columnar shape including a rounded side comprising a plurality of grooves.

[0067] According to exemplary embodiments, when battery cell assemblies (120_2) are designed with rear venting (i.e., venting from the second integrated circuit assembly (125)), a plurality of dispersion structures (113D) can evenly disperse gases and discharges emitted from the battery cell assemblies (120_2) that are in a thermal runaway event, and accordingly, damage caused by gases and discharges is dispersed, so that thermal propagation can be delayed.

[0068] On the other hand, since the side walls (114, 115) are not in the direction of discharge of gas and discharge from the plurality of battery cell assemblies (120_1, 120_2), the inner surface of each of the side walls (114, 115) may not be knurled. The inner surface (114IS, 115IS) of each of the side walls (114, 115) may not include a dispersion structure. The inner surface (114IS, 115IS) of each of the side walls (114, 115) may be flat.

[0069] The battery pack (100) may further include a Battery Management System (BMS). The BMS may be interposed between a plurality of battery cell assemblies (120_, 120_2) and a side wall (114). The BMS may be configured to perform monitoring, balancing, and control of the battery pack. Monitoring of the battery pack (100) may include measuring the voltage and current of specific nodes within the plurality of battery cell assemblies (120_1, 120_2) and measuring the temperature of set locations within the battery pack (100). The battery pack (100) may include measuring instruments for measuring the voltage, current, and temperature described above.

[0070] Balancing of the battery pack (100) is an operation that reduces deviations between multiple battery cell assemblies (120_1, 120_2). Control of the battery pack (100) includes preventing overcharging, over-discharging, and overcurrent. Through monitoring, balancing, and control, the battery pack (100) can operate under optimal conditions, and accordingly, the shortening of the lifespan of each of the multiple battery cell assemblies (120_1, 120_2) can be prevented.

[0071] The battery pack (100) may further include exhaust devices. The exhaust devices may be configured to delay heat propagation by releasing high-temperature gas inside the battery pack (100) to the outside when at least one of the plurality of battery cell assemblies (120_1, 120_2) is in a thermal runaway state.

[0072] The battery pack (100) may include additional electrical components. The additional electrical components may include a cooling device, a Power Relay Assembly (PRA), a safety plug, etc. The cooling device may include a cooling fan. The cooling fan can prevent overheating of each of the multiple battery cell assemblies (120_1, 120_2) by circulating air inside the battery pack (100). The PRA may be configured to supply or cut off power from the high-voltage battery to an external load (e.g., a vehicle motor). The PRA can protect the multiple battery cell assemblies (120_1, 120_2) and the external load (e.g., a vehicle motor) by cutting off power supply to the external load (e.g., a vehicle motor) in situations where abnormal voltage, such as a voltage surge, occurs.

[0073] The battery pack (100) may further include a plurality of busbars configured to electrically connect a plurality of battery cell assemblies (120_1, 120_2). The plurality of battery cell assemblies (120_1, 120_2) may be connected in series by the plurality of busbars. Accordingly, the battery pack (100) may be configured to output a high voltage to an external load (e.g., a motor of a vehicle).

[0074] The battery pack (100) may further include lead plates coupled to side walls (112, 113, 114, 115). The lead plates may cover elements mounted inside the pack housing (110), such as battery cell assemblies (120_1, 120_2) and electrical components. The lead plates may be secured to the pack housing (110) by mechanical coupling means, such as fastening members.

[0075]

[0076] (2nd Example)

[0077] FIG. 3 shows dispersion structures (112D', 113D') according to other exemplary embodiments. The dispersion structures (112D', 113D') of FIG. 3 can replace the dispersion structures (112D, 113D) of FIG. 1 and FIG. 2.

[0078] Referring to FIG. 3, each of the dispersion structures (112D', 113D') may be processed by diamond knurling instead of straight knurling. Accordingly, each of the dispersion structures (112D', 113D') may include a rounded surface. Each of the dispersion structures (112D', 113D') may include a patterned surface. Each of the dispersion structures (112D', 113D') may include a plurality of grooves. Each of the dispersion structures (112D', 113D') may have a columnar shape including a rounded side containing a plurality of grooves. According to embodiments, each of the dispersion structures (112D', 113D') may include a plurality of grooves extending in directions oblique to one another.

[0079]

[0080] (3rd Example)

[0081] FIG. 4 is a plan view showing a battery pack (100') according to exemplary embodiments.

[0082] Referring to FIG. 4, the battery pack (100') may include a pack housing (110') and a plurality of battery cell assemblies (120_1, 120_2). The plurality of battery cell assemblies (120_1, 120_2) are substantially the same as those described with reference to FIG. 1.

[0083] The pack housing (110') is substantially identical to the pack housing (110) of FIG. 1, except that the side wall (112') includes a knurled inner surface (112IS') and the side wall (113') includes a knurled inner surface (113IS'). The inner surfaces (112IS', 113IS') may be substantially flat except for the knurling. That is, the inner surfaces (112IS', 113IS') may be formed by performing straight knurling or diamond knurling on the inner surfaces that are flat of the side walls (112', 113').

[0084] The inner surface (112IS') may include a plurality of grooves formed on a plane. The plurality of grooves may extend in the Z direction similar to FIG. 2. The inner surface (112IS') may also include a plurality of grooves formed on a plane and extending in directions intersecting each other similar to FIG. 3.

[0085] The inner surface (113IS') may include a plurality of grooves formed on a plane. The plurality of grooves may extend in the Z direction, similar to FIG. 2. The inner surface (113IS') may also include a plurality of grooves formed on a plane and extending in directions intersecting each other, similar to FIG. 3.

[0086]

[0087] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

Claims

1. A pack housing comprising 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 comprises a plurality of battery cells arranged in a first direction parallel to the mounting surface of the base plate, and A battery pack characterized in that the first side wall is located on a first inner surface facing the first battery cell assembly and includes a plurality of first dispersion structures arranged in the first direction.

2. In Paragraph 1, A battery pack characterized in that each of the above plurality of first dispersion structures includes a rounded surface.

3. In Paragraph 1, A battery pack characterized in that each of the plurality of first dispersion structures comprises a patterned surface.

4. In Paragraph 1, A battery pack characterized in that each of the above plurality of first dispersion structures has a columnar shape including a rounded side including a plurality of grooves.

5. In Paragraph 4, A battery pack characterized in that each of the plurality of grooves extends in a direction perpendicular to the mounting surface.

6. In Paragraph 1, A battery pack characterized in that each of the above plurality of first dispersion structures includes a plurality of grooves extending in a direction intersecting each other.

7. In Paragraph 1, A battery pack characterized in that the second side wall is located on a second inner surface facing the second battery cell assembly and includes a plurality of second dispersion structures arranged in the first direction.

8. In Paragraph 1, The above pack housing further includes third and fourth side walls perpendicular to the base plate, and A battery pack characterized in that the third inner surface of the third side wall and the fourth inner surface of the fourth side wall are each flat.

9. Pack housing comprising 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 comprises a plurality of battery cells arranged in a first direction parallel to the mounting surface of the base plate, and A battery pack characterized in that the first side wall includes a first inner surface that faces the first battery cell assembly and is knurled.

10. In Paragraph 9, A battery pack characterized in that the first inner surface includes a plurality of grooves formed on a flat surface.

11. In Paragraph 10, A battery pack characterized in that each of the plurality of grooves extends in a direction perpendicular to the mounting surface.

12. In Paragraph 9, A battery pack characterized in that the first inner surface is formed on a plane and includes a plurality of grooves extending in directions intersecting each other.

13. In Paragraph 9, A battery pack characterized in that the second side wall includes a second inner surface that faces the second battery cell assembly and is knurled.

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