Lifting jig and method for lifting battery cell assembly using same

Abstract

According to exemplary embodiments, a lifting jig is provided. The lifting jig includes a plate and a plurality of fixing pads coupled to the plate. The plate includes holes for coupling to side beams of a battery cell assembly. The battery cell assembly includes the side beams and a plurality of battery cells interposed between the side beams.

Description

Lifting jig and method for lifting a battery cell assembly using the same

[0001] The present invention relates to a lifting jig and a method for lifting a battery cell assembly using the same. The present application claims the benefit of Korean application No. 10-2024-0129556, filed on September 25, 2024, which is incorporated herein by reference in its entirety.

[0002]

[0003] 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.

[0004] 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.

[0005] One of the powerful solutions for increasing the energy density of secondary batteries is the modular type battery pack (or cell-to-pack structure). Since the modules covering the battery cells are omitted in the modular type battery pack, the mass of the battery pack can be drastically reduced.

[0006]

[0007] The problem that the technical concept of the present invention aims to solve is to provide a lifting jig with enhanced reliability and a method for lifting a battery cell assembly using the same.

[0008]

[0009] According to exemplary embodiments of the present invention for solving the above-described problem, a lifting jig is provided. The lifting jig comprises a plate and a plurality of fixing pads coupled to the plate. The plate comprises holes for coupling to side beams of a battery cell assembly. The battery cell assembly comprises the side beams and a plurality of battery cells interposed between the side beams.

[0010] At least two of the plurality of fixed pads are configured to apply different pressures to the battery cell assembly.

[0011] The pressure applied by the plurality of fixed pads to the battery cell assembly increases as it moves toward the center of the plurality of fixed pads, based on the direction in which the plurality of fixed pads are stacked.

[0012] It further includes a pressure control unit configured to be connected to each of the plurality of fixed pads and to control the pressure that each of the plurality of fixed pads applies to the battery cell assembly.

[0013] The above side beams include holes. They further include bolts passing through the holes of the plate and the holes of the side beams.

[0014] The above plate includes a first plate coupled to the plurality of fixed pads, and a second plate spaced apart from the first plate and bolted to the side beams. It further includes a rod connecting the first plate and the second plate, and a driving unit that controls the length of the rod to adjust the gap between the first plate and the second plate.

[0015] The plurality of fixing pads includes first fixing pads arranged to overlap each other in a first direction, and second fixing pads arranged to overlap each other in the first direction. Each of the first fixing pads is spaced apart from each of the second fixing pads in a second direction different from the first direction.

[0016] Each of the above battery cells is vertically overlapped with a corresponding one of the first fixing pads and a corresponding one of the second fixing pads.

[0017] Each of the above-mentioned plurality of fixed pads is arranged to overlap in the horizontal direction and overlaps in the vertical direction with two or more of the plurality of battery cells.

[0018] The length of each of the above-mentioned fixed pads is equal to or smaller than the length of each of the above-mentioned battery cells.

[0019] The width of each of the above-mentioned fixed pads is equal to or greater than the width of each of the above-mentioned battery cells.

[0020] According to exemplary embodiments, a method for lifting a battery cell assembly is provided. The method includes the step of applying different vacuum pressures in a vertical direction to a plurality of battery cells of the battery cell assembly.

[0021] The method further includes the step of applying a compressive force to the battery cell assembly based on the stacking direction of the plurality of battery cells.

[0022] The above battery cell assembly further includes the step of separating it from the base of the battery pack housing.

[0023] According to exemplary embodiments, a method for lifting a battery cell assembly is provided. The method comprises the steps of: fixing a plurality of battery cells of a battery cell assembly to a plurality of fixing pads of a lifting jig; and bolting side beams of the battery cell assembly to the lifting jig.

[0024]

[0025] According to exemplary embodiments of the present invention, a battery cell assembly can be stably fixed to a lifting jig using fixing pads. Accordingly, when lifting the battery cell assembly, misalignment of the battery cell assembly, sagging of the lower portion, and cracking can be prevented.

[0026] 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.

[0027]

[0028] FIG. 1 is a top view showing a lifting jig according to exemplary embodiments.

[0029] FIG. 2 is a bottom view showing a lifting jig according to exemplary embodiments.

[0030] FIGS. 3 and FIGS. 4 are cross-sectional views showing a lifting jig according to exemplary embodiments.

[0031] FIGS. 5 and FIGS. 6 are perspective views showing a lifting jig according to exemplary embodiments.

[0032] FIG. 7 is a cross-sectional view showing a lifting jig according to exemplary embodiments.

[0033] FIG. 8 is a perspective view showing a lifting jig according to exemplary embodiments.

[0034] FIG. 9 is a flowchart illustrating a method for lifting a battery cell assembly according to exemplary embodiments.

[0035]

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040]

[0041] (1st embodiment)

[0042] FIG. 1 is a top view showing a lifting jig (100) according to exemplary embodiments. FIG. 2 is a bottom view showing a lifting jig (100) according to exemplary embodiments.

[0043] FIGS. 3 and 4 are cross-sectional views showing a lifting jig (100) according to exemplary embodiments. FIG. 3 illustrates an embodiment in which a battery cell assembly (CA) is fixed to the lifting jig (100). FIG. 4 illustrates only the lifting jig (100). FIGS. 3 and 4 are cross-sectional views of the lifting jig (100) cut along the line A-A' of FIGS. 1 and 2.

[0044] FIG. 5 is a perspective view showing a lifting jig (100) according to exemplary embodiments. FIG. 5 shows the positional relationship between the lifting jig (100) and a battery cell assembly (CA). FIG. 6 illustrates an embodiment in which the battery cell assembly (CA) is fixed to the fixing pads (102A, 102B, 102C) of the lifting jig. FIG. 6 excludes the plate of the lifting jig and shows only the fixing pads (102A, 102B, 102C).

[0045]

[0046] Referring to FIGS. 1 to 6, the lifting jig (100) may include a plate (101), fixing pads (102A, 102B, 102C), bolts (105), and a pressure control unit (106).

[0047] A lifting jig (100) may be configured to secure a battery cell assembly (CA) for lifting the battery cell assembly (CA). The battery cell assembly (CA) may be transported by the lifting jig (100) lifting, moving, and lowering the battery cell assembly (CA) coupled to the lifting jig (100). According to exemplary embodiments, if a defect occurs in one of the battery cell assemblies (CA), only the battery cell assembly (CA) may be lifted and selectively removed from the battery pack housing.

[0048] A battery cell assembly (CA) may include battery cells (CL), separators (SP), and side beams (SB). According to exemplary embodiments, the battery cell assembly (CA) may not include a module frame. A plurality of battery cells (CL) and a plurality of separators (SP) may form a cell stack. According to exemplary embodiments, each of the plurality of battery cells (CL) may be bidirectional cells. That is, the positive terminals of the plurality of battery cells (CL) may be placed at each end, and the negative terminals of the plurality of battery cells (CL) may be placed at each other end. A person skilled in the art will be able to easily arrive at an embodiment in which each of the plurality of battery cells (CL) is a unidirectional cell based on what is described herein.

[0049] Each of the plurality of battery cells (CL) includes an electrode assembly, an electrolyte, and a case covering them. The case may be any one of a pouch case, a cylindrical case, and a prismatic case. The pouch case may include an aluminum laminate sheet. The prismatic case and the cylindrical case may include a metallic material such as aluminum. The prismatic case may have a rectangular prism shape. The cylindrical case may have a cylinder shape.

[0050] An electrode assembly embedded in a case includes a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes. Depending on the assembly form, 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 a positive electrode, a negative electrode, and a separator interposed between them. A stack type electrode assembly includes a plurality of positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed between them, which are stacked sequentially. According to exemplary embodiments, a plurality of battery cells (CL) connected in parallel may form a plurality of banks, and the plurality of banks may be connected in series. The output current of a battery cell assembly (CA) may be determined according to the number of battery cells (CL) included in each of the plurality of banks. The output voltage of a battery cell assembly (CA) may be determined according to the number of the plurality of banks connected in series.

[0051] A plurality of separators (SP) may be interposed between a plurality of battery cells (CL). The plurality of separators (SP) may include a compressible material. The plurality of separators (SP) may absorb swelling of the plurality of battery cells (CL).

[0052] According to exemplary embodiments, a plurality of separators (SP) may be thermal barriers. According to exemplary embodiments, each of the plurality of separators (SP) may have a high melting temperature and low thermal conductivity. According to exemplary embodiments, each of the plurality of separators (SP) may include a flame-retardant material such as ceramic and coated glass material. According to exemplary embodiments, the plurality of separators (SP) may be configured to release a fire retarding material and a fire extinguishing agent in the event of a thermal runaway event.

[0053] The side beams (SB) can be spaced apart from each other with the battery cells (CL) and separators (SP) in between. The side beams (SB) can cover the battery cells (CL). Each side beam (SB) can have a shape symmetrical with respect to the battery cells (CL). The side beams (SB) can be fixed to the cell stack by means of an adhesive material, etc.

[0054] Each side beam (SB) may include a first portion (SB1) extending along the Z direction and a second portion (SB2) extending along the X direction. The first portion (SB1) may be fixed to the cell stack. The second portion (SB2) may be parallel to the plate (101) of the lifting jig (100). The second portion (SB2) may be joined to the plate (101) of the lifting jig (100) by a method such as bolting.

[0055] The second part (SB2) may include a plurality of holes (SBH). The plurality of holes (SBH) of the second part (SB2) may be arranged along the Y direction. According to exemplary embodiments, the plurality of holes (SBH) of the second part (SB2) may be arranged along the longitudinal direction of the side beams (SB). The number of the plurality of holes (SBH) of the second part (SB2) may vary depending on the length of the side beams (SB), the number of battery cells (CL), the weight of the battery cells (CL), etc. According to exemplary embodiments, each side beam (SB) may include 4 to 12 plurality of holes (SBH).

[0056] A battery cell assembly (CA) may be mounted in a battery pack housing. The battery cell assembly (CA) may be fixed to the base (114) of the battery pack housing by an adhesive material such as resin. A lifting jig (100) may be configured to fix the battery cell assembly (CA). By lifting the lifting jig (100) that fixes the battery cell assembly (CA), the battery cell assembly (CA) can be separated from the base (114) of the battery pack housing. The lifting jig (100) may cover all or part of the battery cell assembly (CA).

[0057] The plate (101) may include a plurality of holes (104). According to exemplary embodiments, the plurality of holes (104) may be arranged in one direction along the edge of the plate (101). The plurality of holes (104) of the plate (101) may be aligned with the plurality of holes (SBH) of the side beams (SB) of the battery cell assembly (CA). The number of the plurality of holes (104) of the plate (101) may be equal to the number of the plurality of holes (SBH) of the side beams (SB) of the battery cell assembly (CA). The plate (101) may be bolted to the side beams (SB). The lifting jig (100) may further include bolts passing through the holes (104) of the plate (101) and the holes (SHB) of the side beams (SB).

[0058] The plate (101) may include a first surface (101L) and a second surface (101U) facing the first surface (101L). The plate (101) may include a recessed receiving portion (103) from the first surface (101L) of the plate. The receiving portion (103) may receive fixing pads (102A, 102B, 102C). The fixing pads (102A, 102B, 102C) may be attached to the plate (101) within the receiving portion (103). The fixing pads (102A, 102B, 102C) may be attached to the plate (101) by means of an adhesive material, bolting, etc. A pressure control unit (106) that controls the pressure applied by the fixed pads (102A, 102B, 102C) to the battery cell assembly (CA) may be disposed on the second surface (101U).

[0059] When the lifting jig (100) is loaded onto the battery cell assembly (CA), the fixing pads (102A, 102B, 102C) can apply pressure to the battery cell assembly (CA). According to exemplary embodiments, the fixing pads (102A, 102B, 102C) can apply a vacuum pressure lower than atmospheric pressure to each battery cell (CL). The battery cells (CL) can be adsorbed to the fixing pads (102A, 102B, 102C) and fixed to the lifting jig (100).

[0060] The fixed pads (102A) can be arranged in the X direction. The fixed pads (102A) can overlap each other in the X direction. The fixed pads (102B) can be arranged in the X direction. The fixed pads (102B) can overlap each other in the X direction. The fixed pads (102C) can be arranged in the X direction. The fixed pads (102C) can overlap each other in the X direction.

[0061] Each of the fixed pads (102A) may be spaced apart in the Y direction from each of the fixed pads (102B). Each of the fixed pads (102B) may be spaced apart in the Y direction from each of the fixed pads (102C). The fixed pads (102B) may be interposed between the fixed pads (100A) and the fixed pads (102C).

[0062] The width in the X direction of each of the fixed pads (102A, 102B, 102C) may be substantially the same as the width in the X direction of each of the battery cells (CL). The length in the Y direction of each of the fixed pads (102A, 102B, 102C) may differ from the length in the Y direction of each of the battery cells (CL). The length in the Y direction of each of the fixed pads (102A, 102B, 102C) may be smaller than the length in the Y direction of each of the battery cells (CL).

[0063] When the lifting jig (100) is loaded onto the battery cell assembly (CA), each of the battery cells (CL) may overlap in the Z direction with a corresponding one of the fixing pads (102A), a corresponding one of the fixing pads (102B), and a corresponding one of the fixing pads (102C).

[0064] During the process of lifting the battery cell assembly (CA), different forces of different magnitudes may be applied to each battery cell (CL). For example, the battery cell assembly (CA) is fixed to the base (114) of the battery pack housing by an adhesive material, and the adhesive strength between the adhesive material and each battery cell (CL) may differ. When lifting the battery cell assembly (CA), the difference in adhesive strength applied to the battery cells (CL) may cause misalignment of the battery cell assembly (CA), sagging of the bottom part of the battery cell assembly (CA), cracking, etc.

[0065] To prevent such problems, at least some of the fixing pads (102A, 102B, 102C) may apply different pressures to the battery cell assembly (CA). According to exemplary embodiments, the fixing pads (102A) may apply greater pressure to the battery cell assembly (CA) as they are directed toward the center of the fixing pads (102A) in the X direction. The fixing pads (102B) may apply greater pressure to the battery cell assembly (CA) as they are directed toward the center of the fixing pads (102B) in the X direction. The fixing pads (102C) may apply greater pressure to the battery cell assembly (CA) as they are directed toward the center of the fixing pads (102C) in the X direction. As a result, even if there is a difference in the adhesive strength between each battery cell (CL) included in the battery cell assembly (CA) and the base (114), the battery cell assembly (CA) can be lifted stably without deformation such as sagging of the bottom or cracking.

[0066] The lifting jig (100) may further include a pressure control unit (106). The pressure control unit (106) may be configured to individually control the vacuum pressure of each of the fixed pads (102A, 102B, 102C). The pressure control unit may include a vacuum pump, vacuum pipes connecting the vacuum pump to each of the fixed pads (102A, 102B, 102C), and valves coupled to each of the vacuum pipes.

[0067]

[0068] (2nd Example)

[0069] FIG. 7 is a cross-sectional view showing a lifting jig (200) according to exemplary embodiments. In FIG. 7, components having the same reference numerals as FIG. 1 to FIG. 6 may be described as described above in the first embodiment, and such descriptions will be omitted. Hereinafter, the description will focus on the components of the second embodiment that differ from the first embodiment.

[0070] In FIG. 7, the plate (201) of the lifting jig (200) may include a first plate (201A) and a second plate (202B). The first plate (201A) may be coupled with fixing pads (102B). The second plate (202B) may be spaced apart from the first plate (201A). The second plate (202B) may be bolted to the side beams (SB) of the battery cell assembly (CA) by bolts (105).

[0071] The lifting jig (200) may further include a compression section comprising a rod (202) and a drive unit (203). The rod (202) may connect the first plate (201A) and the second plate (201B). The lifting jig (200) may include one rod or two or more rods. The drive unit (203) may be configured to control the length of the rod (202). The drive unit (203) may include a motor, etc. When the lifting jig (200) is loaded onto the battery cell assembly (CA), the drive unit (203) may control the length of the rod (202) to pull the second plate (201B) in a direction toward the first plate (201A). The side beams (SB) bolted to the second plate (201B) may apply a compressive force (F1) in the X direction to the battery cells (CL).

[0072] Some of the battery cells (CL) of the battery cell assembly (CA) may swell. An expansion force may be applied to the battery cell assembly (CA) by the swollen battery cells (CL). When the battery cell assembly (CA) is lifted in the Z direction, the alignment of the battery cell assembly (CA) may be misaligned due to the expansion force. The compressive force (F1) in the X direction acting on the battery cells (CL) can prevent the problem of misalignment of the battery cell assembly (CA). Additionally, it can prevent sagging of the bottom part of the battery cell assembly (CA) and the occurrence of cracks.

[0073]

[0074] (3rd Example)

[0075] FIG. 8 is a perspective view showing a lifting jig (300) according to exemplary embodiments. In FIG. 8, components having the same reference numerals as FIG. 1 to FIG. 6 may be described as described above in the first embodiment, and such descriptions will be omitted. Hereinafter, the components of the third embodiment, which differ from the first embodiment, will be described in detail.

[0076] In FIG. 8, the lifting jig (300) differs from the lifting jig (100) of FIG. 1 through 6 in the shape and number of fixing pads (302). In FIG. 8, the plate of the lifting jig (300) is omitted, and only the fixing pads (302) are shown. Each fixing pad (302) can be arranged to overlap in the X direction. Each fixing pad (302) can overlap with a plurality of battery cells (CL) in the Z direction. As shown in FIG. 8, each fixing pad (302) can overlap with three battery cells (CL) in the Z direction. However, the shape and number of fixing pads (302) are not limited thereto and can be varied depending on the type of battery cells. According to exemplary embodiments, each fixing pad can overlap with all battery cells (CL) between adjacent separators (SP) in the Z direction.

[0077]

[0078] (Fourth Example)

[0079] FIG. 9 is a flowchart illustrating a method for lifting a battery cell assembly according to exemplary embodiments.

[0080] Referring to FIGS. 1 through 6 and FIG. 9, in P1, vacuum pressure can be applied to a battery cell assembly (CA). The vacuum pressure can be applied by the fixing pads (102A, 102B, 102C) of the lifting jig (100). Each fixing pad (102A, 102B, 102C) can apply a different vacuum pressure to each battery cell (CL). By the vacuum pressure applied by the fixing pads (102A, 102B, 102C), the battery cell assembly (CA) can be fixed to the lifting jig (100).

[0081] In P2, the side beams (SB) of the battery cell assembly (CA) can be bolted to the lifting jig (100). Bolting the side beams (SB) to the lifting jig (100) may include aligning the holes (SBH) of the side beams (SB) with the holes (104) of the plate (101), and attaching bolts (105) to the holes (SBH, 104). The order of P1 and P2 is not limited to that shown in FIG. 9. P2 may be performed prior to P1.

[0082] Referring to FIGS. 7 and 9, at P3, a compressive force (F1) can be applied to the battery cell assembly (CA) by pressing the side beams (SB). By using the compression part of the lifting jig (200), a compressive force (F1) can be applied to the side beams (SB) of the battery cell assembly (CA) in the X direction.

[0083] In P4, the battery cell assembly (CA) can be lifted. The battery cell assembly (CA) can be separated from the base (114) of the battery pack housing and removed from the battery pack housing.

[0084] 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. Plate, and It includes a plurality of fixing pads coupled to the above plate, and The above plate includes holes for coupling to the side beams of the battery cell assembly, and A lifting jig characterized in that the battery cell assembly comprises the side beams and a plurality of battery cells interposed between the side beams.

2. In Paragraph 1, A lifting jig characterized in that at least two of the plurality of fixing pads are configured to apply different pressures to the battery cell assembly.

3. In Paragraph 1, A lifting jig characterized in that the pressure applied by the plurality of fixing pads to the battery cell assembly increases as it moves toward the center of the plurality of fixing pads, based on the direction in which the plurality of fixing pads are stacked.

4. In Paragraph 1, A lifting jig further comprising a pressure control unit connected to each of the plurality of fixed pads and configured to control the pressure applied by each of the plurality of fixed pads to the battery cell assembly.

5. In Paragraph 1, The above side beams include holes, A lifting jig further comprising bolts passing through the holes of the plate and the holes of the side beams.

6. In Paragraph 1, The above plate includes a first plate coupled to the plurality of fixed pads, and a second plate spaced apart from the first plate and bolted to the side beams. A lifting jig further comprising a rod connecting the first plate and the second plate, and a driving unit that controls the length of the rod to adjust the gap between the first plate and the second plate.

7. In Paragraph 1, The plurality of fixing pads includes first fixing pads arranged to overlap each other in a first direction, and second fixing pads arranged to overlap each other in the first direction. A lifting jig characterized in that each of the first fixing pads is spaced apart from each of the second fixing pads in a second direction different from the first direction.

8. In Paragraph 7, A lifting jig characterized in that each of the above-mentioned battery cells overlaps in a vertical direction with a corresponding one of the first fixing pads and a corresponding one of the second fixing pads.

9. In Paragraph 1, A lifting jig characterized in that each of the plurality of fixed pads is arranged to overlap in a horizontal direction and overlaps in a vertical direction with two or more of the plurality of battery cells.

10. In Paragraph 1, A lifting jig characterized in that the length of each of the above-mentioned fixed pads is equal to the length of each of the above-mentioned battery cells or is shorter than the length of each of the above-mentioned battery cells.

11. In Paragraph 1, A lifting jig characterized in that the width of each of the above-mentioned fixed pads is equal to or greater than the width of each of the above-mentioned battery cells.

12. A method for lifting a battery cell assembly, comprising the step of applying different vacuum pressures in a vertical direction to a plurality of battery cells of a battery cell assembly.

13. In Paragraph 12, A method for lifting a battery cell assembly, further comprising the step of applying a compressive force to the battery cell assembly based on the stacking direction of the plurality of battery cells.

14. In Paragraph 12, A method for lifting a battery cell assembly, further comprising the step of separating the battery cell assembly from the base of the battery pack housing.

15. A step of securing a plurality of battery cells of a battery cell assembly to a plurality of fixing pads of a lifting jig; and A method for lifting a battery cell assembly, comprising the step of bolting the side beams of the battery cell assembly to the lifting jig.

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