Battery cell assembly and battery pack comprising same

Abstract

Provided according to exemplary embodiments is a battery pack. The battery pack comprises: a module frame including a bottom plate, sidewalls connected to the bottom plate, and a top plate connected to the sidewalls; a plurality of battery cells located in the module frame and arranged in a first direction parallel to the bottom plate; thermal separators between the plurality of battery cells; and an upper cover over the thermal separators, wherein the upper cover has a corrugated structure.

Description

Battery cell assembly and battery pack including the same

[0001] The present invention relates to a battery cell assembly and a battery pack comprising the same. The present application claims the benefit of Korean application No. 10-2024-0163558, filed on November 15, 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 technological development trend for rechargeable batteries in mobility is the improvement of energy density and safety. Here, the energy density of a rechargeable battery is defined as the maximum electrical energy that can be stored by the battery's mass. As high energy density is directly linked to driving efficiency and range in mobility applications, various studies are being conducted to improve this energy density.

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

[0005] According to exemplary embodiments for solving the above-described problem, a battery pack is provided. The battery pack comprises: a module frame including a bottom plate, a side wall connected to the bottom plate, and a top plate connected to the side wall; a plurality of battery cells within the module frame and arranged in a first direction parallel to the bottom plate; thermal separators between the plurality of battery cells; and an upper cover over the thermal separators, wherein the upper cover has a corrugated structure.

[0006] The upper cover includes mounting parts and protective parts that alternate in the first direction.

[0007] The distance between each of the above mounting parts and the bottom plate is different from the distance between each of the above protection parts and the bottom plate.

[0008] The distance between each of the above mounting parts and the bottom plate is greater than the distance between each of the above protection parts and the bottom plate.

[0009] Each of the above mounting parts overlaps with a corresponding one of the above thermal separators in a second direction perpendicular to the bottom plate, and each of the above protection parts overlaps with a corresponding one of the plurality of battery cells in the second direction.

[0010] Each of the above mounting parts is in contact with a corresponding one of the above thermal separators.

[0011] Each of the above protective parts is in contact with a corresponding one of the plurality of battery cells.

[0012] Each of the above protective parts is spaced apart from each of the plurality of battery cells.

[0013] The second directional height perpendicular to the bottom plate of each of the above thermal separators is different from the second directional height of the plurality of battery cells.

[0014] The second directional height perpendicular to the bottom plate of each of the above thermal separators is greater than the second directional height of the plurality of battery cells.

[0015] Each of the above thermal separators contains a compressible material.

[0016] The above upper cover includes aluminum.

[0017] The upper top plate includes venting holes, and the upper cover is located between the thermal separators and the upper top plate.

[0018] According to exemplary embodiments of the present invention, when a thermal runaway event occurs in a battery cell assembly, thermal separators and an upper cover can thermally isolate the battery cells. Accordingly, the propagation of a thermal runaway event occurring in some of the battery cells to surrounding battery cells can be prevented, and the safety of the battery cell assembly can be enhanced.

[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 cross-sectional view of a battery cell assembly according to exemplary embodiments.

[0021] FIG. 2 is a drawing showing the effect of a battery cell assembly according to exemplary embodiments.

[0022] FIG. 3 is a cross-sectional view of a battery cell assembly according to other exemplary embodiments.

[0023] FIG. 4 is a plan view of 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 embodiment)

[0030] FIG. 1 is a cross-sectional view of a battery cell assembly (120) according to exemplary embodiments.

[0031] Referring to FIG. 1, the battery cell assembly (120) may include a plurality of battery cells (121), thermal separators (122), a module frame (125), and an upper cover (127).

[0032] Each of the plurality of battery cells (121) may include an electrode assembly, an electrolyte, and a case. Each of the plurality of battery cells (121) 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.

[0033] An electrode assembly includes an anode, a cathode, and a separator interposed between the anode and the cathode. A jelly roll type electrode assembly is formed by winding an anode, a cathode, and a separator interposed between them. A stack type electrode assembly includes a plurality of anodes, a plurality of cathodes, and a plurality of separators interposed between them, which are stacked sequentially.

[0034] A plurality of battery cells (121) may be arranged in the X direction. Hereinafter, the technical concept of the present invention will be explained with reference to an example in which a plurality of battery cells (121) are bidirectional cells comprising output terminals (e.g., electrode leads) spaced apart in the Y direction perpendicular to the X direction. However, this is merely an example and does not limit the technical concept of the present invention in any sense.

[0035] According to exemplary embodiments, a plurality of battery cells (121) may form a plurality of banks. A plurality of banks may include one or more parallel-connected battery cells (121). A plurality of banks may be connected in series with each other. The number of battery cells (121) included in each of the plurality of banks and the number of banks connected in series with each other may be determined according to the voltage and current to be output through the battery cell assembly (120).

[0036] Thermal separators (122) may be located between multiple battery cells (121). The thermal separators (122) may include a compressible material and may absorb swelling of the multiple battery cells. According to exemplary embodiments, each of the thermal separators (122) may be a thermal barrier. According to exemplary embodiments, each of the thermal separators (122) may have a high melting temperature and low thermal conductivity. According to exemplary embodiments, each of the thermal separators (122) may include a flame-retardant material, such as ceramic and coated glass material. According to exemplary embodiments, the thermal separators (122) may be configured to release a fire retarding material and a fire extinguishing agent in the event of a thermal runaway event in the multiple battery cells (121).

[0037] Thermal runaway is a condition in which a temperature change in battery cell assemblies (120) further accelerates that temperature change, which is an uncontrollable positive feedback. Battery cells (121) in a thermal runaway state exhibit a rapid temperature rise and emit large amounts of high-pressure gas and combustion residue.

[0038] The height in the Z direction of each of the thermal separators (122) may differ from the height in the Z direction of each of the plurality of battery cells (121). The height in the Z direction of each of the thermal separators (122) may be greater than the height in the Z direction of each of the plurality of battery cells (121).

[0039] A plurality of battery cells (121) and thermal separators (122) may be located within a module frame (125). The module frame (125) may include a bottom plate (125B), side walls (125S), and a top plate (125T). Each of the bottom plate (125B) and the top plate (125T) may be substantially perpendicular to the Z direction. The bottom plate (125B) may be substantially parallel to the X direction and the Y direction, respectively. The Z direction may be substantially perpendicular to the X direction and the Y direction, respectively. Each of the side walls (125S) may be substantially perpendicular to the X direction. Each of the side walls (125S) may be connected to the bottom plate (125B) and the top plate (125T). The top plate (125T) may include venting holes (125TH).

[0040] In FIG. 1, the module frame (125) is depicted as a monoframe, but this is for illustrative purposes only and does not limit the technical concept of the invention in any sense. A person skilled in the art will be able to easily arrive at an embodiment in which the module frame comprises a U-shaped frame composed of a bottom plate (125B) and side walls (125S) and a top plate (125T) coupled to the U-shaped frame, based on what is described herein.

[0041] The upper cover (127) may be on a plurality of battery cells (121). The upper cover (127) may be on thermal separators (122). The upper cover (127) may overlap with the plurality of battery cells (121) in the Z direction. The upper cover (127) may overlap with the thermal separators (122) in the Z direction.

[0042] The upper cover (127) may comprise metal. The upper cover (127) may comprise a material having relatively high rigidity, such as aluminum, for example. The upper cover (127) may be provided through a casting process, but is not limited thereto.

[0043] The upper cover (127) may be located within the module frame (125). The upper cover (127) may be located between the top plate (125T) of the module frame (125) and a plurality of battery cells (121). The upper cover (127) may be located between the top plate (125T) of the module frame (125) and thermal separators (122).

[0044] The upper cover (127) may include mounting parts (127M) and protection parts (127P). The mounting parts (127M) and protection parts (127P) may alternate in the X direction. One of the protection parts (127P) may be located between two adjacent mounting parts (127M). One of the mounting parts (127M) may be located between two adjacent protection parts (127P).

[0045] The mounting sections (127M) may be raised relative to the protective sections (127P). The Z-direction distance between each mounting section (127M) and the bottom plate (125B) may differ from the Z-direction distance between each protective section (127P) and the bottom plate (125B). The Z-direction distance between each mounting section (127M) and the bottom plate (125B) may be greater than the Z-direction distance between each protective section (127P) and the bottom plate (125B).

[0046] The mounting parts (127M) and the protection parts (127P) alternate in the X direction, and the mounting parts (127M) rise in the Z direction relative to the protection parts (127P), so the upper cover (127) may have a corrugated structure.

[0047] Each mounting part (127M) can overlap in the Z direction with a corresponding one of the thermal separators (122). Each mounting part (127M) can come into contact with a corresponding one of the thermal separators (122).

[0048] Each of the protection parts (127P) can overlap in the Z direction with a corresponding one of the plurality of battery cells (121). Each of the protection parts (127P) can come into contact with a corresponding one of the plurality of battery cells (121).

[0049] The battery cell assembly (120) may further include a first integrated circuit assembly, second integrated circuit assemblies, and a Flexible Flat Cable (FFC) assembly. The first integrated circuit assembly may include an insulating frame, an integrated circuit, busbars, sensing plates, sensing bars, temperature sensors, wiring, and an insulating cover.

[0050] The first integrated circuit assembly may include physical and functional configurations for providing electrical connections between a plurality of battery cells (121), outputting the resulting voltage of the plurality of battery cells (121), and measuring the voltage (or current) of nodes within a circuit composed of the plurality of battery cells (121).

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

[0052] The bus bars can be short-circuited to the positive leads of the 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 can be welded to the positive leads of the 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 a plurality of battery cells (121) of the battery cell assembly (120) can be output through the bus bars. The bus bars can 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 inside the battery cell assembly (120). The integrated circuit can be configured to measure the voltage of the nodes through sensing plates and sensing bars.

[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 multiple nodes inside the battery cell assembly (120) can be measured.

[0057] Temperature sensors may be configured to measure the temperature at multiple points of the battery cell assembly (120). The temperature sensors may be spatially distributed, and accordingly, the temperature distribution within the battery cell assembly (120) may 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 and second integrated circuit assemblies may be protected.

[0059] The second integrated circuit assembly is generally similar to the first integrated circuit assembly, except that it does not include busbars. The second integrated circuit assembly may be spaced apart from the first integrated circuit assembly by a plurality of battery cells (121). The second integrated circuit assembly may be connected to the first integrated circuit assembly through an FFC assembly. Accordingly, measurements detected by the second integrated circuit assembly may be transmitted to the first integrated circuit assembly through the FFC assembly.

[0060]

[0061] FIG. 2 is a drawing for explaining the effect of a battery cell assembly (120) according to exemplary embodiments.

[0062] Referring to FIGS. 1 and 2, the protective part (127P) overlapping with the battery cells (121) where a thermal runaway event (TP) occurred can be melted, and accordingly, a venting path through the venting holes (125TH) can be provided. Additionally, since the upper cover (127) may include a material of relatively high rigidity, together with the upper cover (127) and the thermal separators (122), the battery cells (121) where a thermal runaway event (TP) did not occur can be isolated from the high-temperature gas and flames emitted from the battery cells (121) where a thermal runaway event (TP) occurred.

[0063]

[0064] (2nd Example)

[0065] FIG. 3 is a cross-sectional view of a battery cell assembly (120') according to other exemplary embodiments.

[0066] Referring to FIG. 3, the battery cell assembly (120') may include a plurality of battery cells (121), thermal separators (122), a module frame (125), and an upper cover (127'). Since the plurality of battery cells (121), thermal separators (122), and module frame (125) are substantially the same as those described with reference to FIG. 1, a redundant description thereof is omitted.

[0067] Referring to FIG. 3, the upper cover (127') may include mounting portions (127M) and protection portions (127P'). The upper cover (127') is substantially the same as described with reference to FIG. 1, except that the protection portions (127P') are spaced apart from each of the plurality of battery cells (121).

[0068]

[0069] (3rd Example)

[0070] FIG. 4 is a plan view of a battery pack (100) according to exemplary embodiments.

[0071] Referring to FIGS. 1 and FIGS. 4, the battery pack (100) may include a pack housing (110) and battery cell assemblies (120). The battery pack (100) is the final form of a battery system mounted on mobility, etc.

[0072] The pack housing (110) may include a base plate (111), side walls (112, 113, 114, 115), a center beam (116), and cross beams (117, 118, 119). Here, two directions substantially parallel to the mounting surface (111M) of the base plate (111) are defined as the X direction and the Y direction, and a direction substantially perpendicular to the mounting surface of the base plate (111) is defined as the Z direction. The X direction, the Y direction, and the Z direction may be substantially perpendicular to each other. The mounting surface of the base plate (111) may face battery cell assemblies (120).

[0073] The base plate (111) may have a flat shape. Each of the side walls (112, 113, 114, 115) may be substantially perpendicular to the base plate (111). The side walls (112, 113, 114, 115) may be adjacent to the edge portions of the base plate (111). The side walls (112, 113, 114, 115) may be joined to the edge portions of the base plate (111).

[0074] The base plate (111) can be substantially perpendicular to the Z direction. Each of the side walls (112, 113) can be substantially perpendicular to the Y direction. Each of the side walls (114, 115) can be substantially perpendicular to the Y direction.

[0075] The center beam (116) may extend in the X direction. The center beam (116) may be substantially perpendicular to the Y direction. The center beam (116) may be welded to the base plate (111). If the base plate (111) and the center beam (116) are formed by an extrusion process, the center beam (116) may be formed together with the base plate (111).

[0076] The center beam (116) can isolate the battery cell assemblies (120) in the Y direction. Some of the battery cell assemblies (120) may be between the center beam (116) and the side wall (112), and other parts of the battery cell assemblies (120) may be between the center beam (116) and the side wall (113). The center beam (116) may be between the battery cell assemblies (120) in the Y direction.

[0077] Each of the cross beams (117, 118, 119) may extend in the Y direction. Each of the cross beams (117, 118, 119) may be substantially perpendicular to the X direction. Each of the cross beams (117, 118, 119) may be fixed to the base plate (111) by means such as bolting or welding.

[0078] Cross beams (117, 118, 119) can isolate battery cell assemblies (120) in the X direction. Cross beams (118) may be located between battery cell assemblies (120) in the X direction. Each of the battery cell assemblies (120) may be located between the cross beams (117, 118) or between the cross beams (118, 119).

[0079] The cross beams (118) may be located between the cross beams (117, 119). The cross beams (119) may be spaced apart from the cross beams (117) in the X direction with the cross beams (118) in between.

[0080] The center beam (116) and cross beams (117, 118, 119) may be surrounded by side walls (112, 113, 114, 115). Accordingly, the center beam (116) and cross beams (117, 118, 119) may divide the internal space of the battery pack (100) defined by the pack housing (110) and the lid (130).

[0081] Battery cell assemblies (120) may be on the base plate (111) of the pack housing (110). Battery cell assemblies (120) may be arranged in the X direction and the Y direction. In this example, two battery cell assemblies (120) are arranged in the X direction and two battery cell assemblies are arranged in the Y direction, so that the battery cell assemblies (120) form a matrix of 2 rows and 2 columns, but this is for illustrative purposes only and does not limit the technical concept of the invention in any sense.

[0082] The base plate (111) can support the battery cell assemblies (120). The side walls (112, 113, 114, 115) can horizontally surround the battery cell assemblies (120).

[0083] The battery pack (100) may further include leads coupled to the pack housing (110). Accordingly, the leads and the pack housing (110) may define the internal space of the battery pack (100). The leads may be coupled to side walls (112, 113, 114, 115). The leads may be secured to the side walls (112, 113, 114, 115) by methods such as bolting and / or welding. The leads may also be coupled to cross beams (117, 118, 119). The leads may cover elements placed inside the battery pack (100), such as battery cell assemblies (120) and electrical components. The leads may overlap with the battery cell assemblies (120) and the cross beams (117, 118, 119).

[0084] TIM layers may be further provided between each of the battery cell assemblies (120) and the base plate (111). The TIM layers may comprise a resin composition. The TIM layers may be provided by a thermal resin application process.

[0085] The battery pack (100) may further include exhaust devices. The exhaust devices may be coupled to the pack housing (110) or the lead. Under normal conditions, the exhaust devices may close the venting holes of the pack housing (110) or the lead. The exhaust devices may open the venting holes of the pack housing (110) or the lead when at least one of the battery cell assemblies (120) is in a thermal runaway state. Accordingly, high-temperature gases inside the battery pack (100) may be released to the outside, and thermal propagation may be delayed.

[0086] The battery pack (100) may further include interbusbars. Battery cell assemblies (120) may be connected in series by the interbusbars, and the battery pack (100) may output a high voltage.

[0087] The battery pack (100) may further include electrical components. The electrical components may be placed on the pack housing (110). The electrical components may be placed between any one of the side walls (112, 113, 114, 115) where exhaust devices are installed and the battery cell assemblies (120).

[0088] Electrical components may include, for example, a BMS. 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 battery cell assemblies (120) and measuring the temperature of set locations within the battery pack (100). The battery pack (100) may include sensors for measuring the voltage, current, and temperature described above.

[0089] Balancing of the battery pack (100) is an operation that reduces deviations between battery cell assemblies (120). 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 battery cell assembly (120) can be prevented.

[0090] The electrical components may further 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 battery cell assemblies (120) 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 battery cell assemblies (120) 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 occurs, such as a voltage surge.

[0091]

[0092] 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 module frame comprising a bottom plate, a side wall connected to the bottom plate, and a top plate connected to the side wall; A plurality of battery cells located within the module frame and arranged in a first direction parallel to the bottom plate; Thermal separators between the plurality of battery cells; and Includes an upper cover on the above thermal separators, and A battery cell assembly characterized in that the upper cover has a corrugated structure.

2. In Paragraph 1, A battery cell assembly characterized in that the upper cover includes mounting parts and protective parts that alternate in the first direction.

3. In Paragraph 1, A battery cell assembly characterized in that the distance between each of the mounting parts and the bottom plate is different from the distance between each of the protection parts and the bottom plate.

4. In Paragraph 3, A battery cell assembly characterized in that the distance between each of the mounting parts and the bottom plate is greater than the distance between each of the protection parts and the bottom plate.

5. In Paragraph 3, Each of the above mounting parts overlaps with a corresponding one of the above thermal separators in a second direction perpendicular to the bottom plate, and, A battery cell assembly characterized in that each of the above-mentioned protective parts overlaps with a corresponding one of the plurality of battery cells in the second direction.

6. In Paragraph 3, A battery cell assembly characterized in that each of the above-mentioned mounting parts contacts a corresponding one of the above-mentioned thermal separators.

7. In Paragraph 3, A battery cell assembly characterized in that each of the above-mentioned protective parts contacts a corresponding one of the plurality of battery cells.

8. In Paragraph 3, A battery cell assembly characterized in that each of the above-mentioned protective parts is spaced apart from each of the plurality of battery cells.

9. In Paragraph 1, A battery cell assembly characterized in that the second directional height perpendicular to the bottom plate of each of the above thermal separators is different from the second directional height of the plurality of battery cells.

10. In Paragraph 9, A battery cell assembly characterized in that the second directional height perpendicular to the bottom plate of each of the above thermal separators is greater than the second directional height of the plurality of battery cells.

11. In Paragraph 9, A battery cell assembly characterized in that each of the above thermal separators comprises a compressible material.

12. In Paragraph 1, A battery cell assembly characterized in that the upper cover comprises aluminum.

13. In Paragraph 1, The above top plate includes venting holes, and A battery cell assembly characterized in that the upper cover is located between the thermal separators and the upper top plate.

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