Battery pack and battery pack assembly method

Abstract

According to exemplary embodiments of the present invention, a battery pack is provided. The battery pack includes a base plate, a lower frame including a first side plate connected to a first side of the base plate, and a second side plate connected to a second side of the base plate, a first battery assembly and a second battery assembly disposed on the base plate, each of the first and second battery assemblies including a cell stack comprising a plurality of battery cells and a first crossbeam coupled to the first side of the cell stack.

Description

Technical Field

[0001] The present invention relates to a battery pack and a method for assembling a battery pack. More specifically, the present invention relates to a battery pack and a method for assembling a battery pack, in which the convenience of assembly is improved and the ease of the process is improved. This application claims the benefit of Korean Application No. 10-2023-0095119, filed on July 21, 2023, which is hereby incorporated by reference in its entirety.

Background Art

[0002] A secondary battery can be charged and discharged multiple times and is used as an energy source for various electronic devices. As technology develops, secondary batteries are used not only in portable devices but also in mobility such as electric vehicles (EVs) or hybrid electric vehicles (HEVs) in the form of battery modules or battery packs.

[0003] A battery pack can be manufactured by assembling a plurality of battery assemblies and various configurations that enclose them. At this time, arranging the above configurations in appropriate positions can have an important impact on quality stability and manufacturing speed. For example, if the assembly property of the battery pack is low, work errors are likely to occur in the process, which may cause a decrease in quality. Accordingly, various studies have been conducted to improve the assembly property of the battery pack.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Therefore, the problem to be solved by the first technical idea of the present invention is to provide a battery pack with improved assembly property. The problem to be solved by the second technical idea of the present invention is to provide a method for assembling a battery pack with improved assembly property. [Means for solving the problem]

[0005] According to an exemplary embodiment of the present invention for solving the first problem described above, a battery pack is provided. The battery pack includes a base plate, a lower frame including a first side plate connected to a first side of the base plate, and a second side plate connected to a second side of the base plate, and a first battery assembly and a second battery assembly disposed on the base plate, wherein each of the first and second battery assemblies includes a cell stack including a plurality of battery cells and a first cross beam coupled to the first side of the cell stack, the first cross beam having a first stepped structure including sequentially connected first coupling surfaces, second coupling surfaces, and third coupling surfaces, and the first cross beam including a first groove recessed into the second coupling surface.

[0006] In an exemplary embodiment, the second bonding surface is parallel to the upper surface of the base plate, the first bonding surface is perpendicular to the second bonding surface, and the third bonding surface is perpendicular to the second bonding surface.

[0007] In an exemplary embodiment, the first side plate includes a protruding structure inserted into the first groove, the protruding structure extending in a first direction parallel to the upper surface of the base plate.

[0008] In an exemplary embodiment, the battery pack is characterized in that each of the first and second battery assemblies further includes a second crossbeam coupled to the second side of the cell stack, the second side being opposite to the first side, and the second crossbeam having a second stepped structure including sequentially coupled fourth, fifth, and sixth coupling surfaces, the fifth coupling surface including an inwardly recessed second groove and a handle partially embedded in the second groove, and the handle being configured to rotate.

[0009] In an exemplary embodiment, the rotation axis of the handle is embedded in the second groove, and the rotation axis is parallel to the first direction which is parallel to the upper surface of the base plate.

[0010] In an exemplary embodiment, the axis of rotation of the handle is parallel to the fourth coupling surface.

[0011] In an exemplary embodiment, the fifth bonding surface is parallel to the upper surface of the base plate, the fourth bonding surface is perpendicular to the fifth bonding surface, and the sixth bonding surface is perpendicular to the fifth bonding surface.

[0012] In an exemplary embodiment, the fifth coupling surface of the second crossbeam of the first battery assembly is in contact with the second coupling surface of the first crossbeam of the second battery assembly.

[0013] In an exemplary embodiment, the fourth coupling surface of the second crossbeam of the first battery assembly is in contact with the first coupling surface of the first crossbeam of the second battery assembly, and the sixth coupling surface of the second crossbeam of the first battery assembly is in contact with the third coupling surface of the first crossbeam of the second battery assembly.

[0014] In an exemplary embodiment, the height of the handle of the second crossbeam is the same as or lower than the depth of the first groove of the first crossbeam.

[0015] In an exemplary embodiment, the handle is hinged to the second groove, and the depth of the second groove is the same as or greater than the thickness of the handle.

[0016] In an exemplary embodiment, the battery pack includes a lower frame including a base plate, a first battery assembly and a second battery assembly disposed on the base plate, each of the first and second battery assemblies including a cell stack including a plurality of battery cells, a first crossbeam coupled to a first side of the cell stack and a second crossbeam coupled to a second side of the cell stack, wherein the second side is opposite to the first side, the first crossbeam includes a plurality of inwardly recessed first grooves, and the second crossbeam includes a plurality of inwardly recessed second grooves and a plurality of handles, each of the plurality of handles being partially embedded in a corresponding of the plurality of second grooves.

[0017] In an exemplary embodiment, each of the plurality of handles of the second crossbeam is coupled to a corresponding of the plurality of first grooves of the first crossbeam, the handles are configured to be rotatable by a pivot shaft, and the pivot shaft is embedded in the second groove and parallel to the first direction which is parallel to the upper surface of the base plate.

[0018] On the other hand, according to an exemplary embodiment of the present invention for solving the second problem described above, a method for assembling a battery pack is provided. The method for assembling the battery pack includes the steps of providing a first battery assembly and a second battery assembly, each of which the first battery assembly and the second battery assembly includes a cell stack, a first crossbeam coupled to the cell stack, and a second crossbeam; placing the first battery assembly on a base plate of a lower frame; and placing the second battery assembly on the base plate and coupling the handle of the second crossbeam of the first battery assembly with the first groove of the first crossbeam of the second battery assembly. In this case, the lower frame includes a base plate, a first side plate connected to a first side of the base plate, and a second side plate connected to a second side of the base plate, and the first crossbeam includes a first groove, and the second crossbeam includes a second groove and a handle hinged to the second groove.

[0019] In an exemplary embodiment, the first battery assembly is positioned on the base plate using the first groove of the first cross beam and the handle of the second cross beam.

[0020] In an exemplary embodiment, the first side plate includes a protruding structure that engages with the first groove, and the first battery assembly is characterized in that the first groove of the first crossbeam engages with the protruding structure of the first side plate when the first battery assembly is placed on the base plate of the lower frame. [Effects of the Invention]

[0021] The battery pack according to an exemplary embodiment of the present invention includes a first cross beam and a second cross beam coupled to a cell stack. The first cross beam includes a first groove, and the second cross beam includes a handle that can be coupled to the first groove. The coupling property and mobility of the first cross beam and the second cross beam can be improved through the first groove and the handle. Thereby, the assembly property of the battery pack and the method of assembling the battery pack can be improved.

[0022] The effects obtainable from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those having ordinary knowledge in the technical field to which the exemplary embodiments of the present disclosure belong from the following description. That is, even the unintended effects associated with implementing the exemplary embodiments of the present disclosure can be derived by those having ordinary knowledge in the technical field from the exemplary embodiments of the present disclosure.

Brief Description of the Drawings

[0023] [Figure 1] It is a perspective view showing a battery pack according to an exemplary embodiment. [Figure 2] It is a cross-sectional view taken along the cutting line A - A' of FIG. 1. [Figure 3] It is a perspective view showing a first cross beam according to an exemplary embodiment. [Figure 4] It is a perspective view showing a second cross beam according to an exemplary embodiment. [Figure 5] It is a perspective view showing a second cross beam in which a handle according to an exemplary embodiment is housed. [Figure 6] It is a partial cross-sectional view obtained by enlarging a portion B of FIG. 2. [Figure 7] It is a cross-sectional view showing a battery pack according to an exemplary embodiment. [Figure 8] It is a cross-sectional view showing a battery pack according to an exemplary embodiment. [Figure 9]This is a flowchart showing a method for assembling a battery pack according to an exemplary embodiment. [Figure 10] These are cross-sectional views of the first and second cross beams according to exemplary embodiments. [Modes for carrying out the invention]

[0024] Preferred embodiments of the present invention will now be described in detail with reference to the attached drawings. Before that, however, terms and words used herein and in the claims shall not be interpreted to be limited to their usual or dictionary meanings, but rather to be interpreted as meanings and concepts consistent with the technical idea of ​​the present invention, based on the principle that an inventor may appropriately define the concepts of terms in order to best describe his own invention.

[0025] Therefore, the embodiments described herein and the configurations shown in the drawings represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention; there may be a variety of equivalents and modifications that can substitute for them at the time of filing.

[0026] Furthermore, in describing the present invention, if it is determined that a specific description of a related known configuration or function would likely obscure the gist of the invention, such detailed description will be omitted.

[0027] Since embodiments of the present invention are provided to more fully explain the invention to an ordinary person, the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect their actual sizes and proportions.

[0028] <Battery Pack>

[0029] (First Embodiment) Figure 1 is a perspective view showing a battery pack 100 according to an exemplary embodiment.

[0030] Figure 2 is a side view along the cutting line A-A' in Figure 1.

[0031] Referring to Figures 1 and 2, the battery pack 100 may include a lower frame 110 and a plurality of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. The lower frame 110 can support the configuration included in the battery pack 100. The lower frame 110 can provide space for the plurality of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 to be mounted. The lower frame 110 may include a base plate 110B, a first side plate 110S1 connected to the first side of the base plate 110B, and a second side plate 110S2 connected to the second side of the base plate 110B. For example, the lower frame 110 may be formed as a single unit.

[0032] Two directions substantially parallel to the upper surface 110BU of the base plate 110B are defined as the X and Y directions, respectively, and the direction substantially perpendicular to the upper surface of the base plate 110B is defined as the Z direction. The X, Y, and Z directions may be substantially perpendicular to each other. The Y direction may be called the first direction. The X direction may be called the second direction. The Z direction may be called the third direction. Unless otherwise stated, the definitions of directions are the same for the following drawings.

[0033] The base plate 110B can support multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. Multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 can be placed on the upper surface 110BU of the base plate 110B.

[0034] The base plate 110B can be configured to cool multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. The base plate 110B may include multiple cooling channels. These multiple cooling channels may extend in the Y direction.

[0035] The side plates 110S1 and 110S2 can be connected to the base plate 110B. The side plates 110S1 and 110S2 can extend in the Z direction from the upper surface 110BU of the base plate 110B. The side plates 110S1 and 110S2 may be substantially perpendicular to the Y direction. The side plates 110S1 and 110S2 and the base plate 110B can provide space for mounting multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. The side plate 110S1 may be called the first side plate, and the side plate 110S2 may be called the second side plate.

[0036] The first side plate 110S1 can be connected to the first side of the base plate 110B. The second side plate 110S2 can be connected to the second side of the base plate 110B. The first side plate 110S1 and the second side plate 110S2 may be parallel to each other. The first side plate 110S1 and the second side plate 110S2 may be spaced apart from each other in the Y direction.

[0037] The battery pack 100 may be the final form of a battery system to be installed in a mobility device or the like. According to an exemplary embodiment, the battery pack 100 may be of a modular type, in which case each of the multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 may include a module frame. According to an exemplary embodiment, the battery pack 100 may be of a moduleless type, in which case each of the multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 may not include a module frame.

[0038] In exemplary embodiments, each of the plurality of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 may include a cell stack 121 containing a plurality of battery cells and a first crossbeam 122. In exemplary embodiments, each of the plurality of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 may include a cell stack 121 containing a plurality of battery cells, a first crossbeam 122, and a second crossbeam 123. The battery cells are the basic units of a lithium-ion battery, i.e., a secondary battery. Each of the plurality of battery cells includes an electrode assembly, an electrolyte, and a case. Each of the plurality of battery cells can be classified as a lithium-ion battery, a lithium-ion polymer battery, a lithium polymer battery, etc., depending on the configuration of the electrode assembly and the electrolyte. Each of the above-mentioned battery cells may be one of the following: a cylindrical battery cell, a prismatic battery cell, or a pouch-type battery cell.

[0039] Multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 can be arranged in the X and Y directions. In Figure 1, the lower frame 110 can provide space for three battery assemblies to be arranged in the X direction and two battery assemblies to be arranged in the Y direction (3x2 arrangement). In addition, the number of multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 is not limited to six, and the multiple battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 can be arranged in MxN (where M and N are integers of 2 or more) in addition to the 3x2 arrangement described above.

[0040] Battery assembly 120_1 can be called the first battery assembly, battery assembly 120_2 can be called the second battery assembly, battery assembly 120_3 can be called the third battery assembly, battery assembly 120_4 can be called the fourth battery assembly, battery assembly 120_5 can be called the fifth battery assembly, and battery assembly 120_6 can be called the sixth battery assembly.

[0041] In an exemplary embodiment, each of the first to third battery assemblies 120_1, 120_2, and 120_3 can be positioned in the X direction, and each of the fourth to sixth battery assemblies 120_4, 120_5, and 120_6 can be positioned in the X direction. In an exemplary embodiment, each of the first battery assembly 120_1 and the fourth battery assembly 120_4 can be separated from each other in the Y direction, each of the second battery assembly 120_2 and the fifth battery assembly 120_5 can be separated from each other in the Y direction, and each of the third battery assembly 120_3 and the sixth battery assembly 120_6 can be separated from each other in the Y direction.

[0042] In exemplary embodiments, each of the first battery assembly 120_1, the second battery assembly 120_2, the fourth battery assembly 120_4, and the fifth battery assembly 120_5 may include a cell stack 121 containing a plurality of battery cells and a first crossbeam 122 coupled to a first side 121S1 of the cell stack 121. In exemplary embodiments, each of the first battery assembly 120_1 and the second battery assembly 120_2 may include a cell stack 121, a first crossbeam 122 coupled to a first side 121S1 of the cell stack 121, and a second crossbeam 123 coupled to a second side 121S2 of the cell stack 121.

[0043] The first crossbeam 122 and the second crossbeam 123 can be positioned on the base plate 110B of the lower frame 110. The first crossbeam 122 and the second crossbeam 123 can extend in the Y direction. The first crossbeam 122 and the second crossbeam 123 can be coupled to the base plate 110B.

[0044] In exemplary embodiments, the first crossbeam 122 can be positioned on the first side 121S1 of the cell stack 121, and the second crossbeam 123 can be positioned on the second side 121S2 of the cell stack 121. This allows the cell stack 121 to be transported using the first crossbeam 122 and the second crossbeam 123 without directly gripping the cell stack 121. This prevents damage to the cell stack 121 during the assembly process of the battery pack 100, thereby improving the yield and safety of the battery pack 100.

[0045] In an exemplary embodiment, the first crossbeam 122 of the first battery cell assembly 120_1 can be interposed between the first side plate 110S1 and the cell stack 121. In an exemplary embodiment, the first crossbeam 122 of the second battery cell assembly 120_2 can be interposed between the second crossbeam 123 of the first battery cell assembly 120_1 and the cell stack 121 of the second battery cell assembly 120_2. The second crossbeam 123 of the second battery cell assembly 120_2 can be interposed between the first crossbeam 122 of the third battery cell assembly 120_3 and the cell stack 121 of the second battery cell assembly 120_2.

[0046] The first crossbeam 122 of each of the battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 can be coupled to the second crossbeam 123 of the preceding battery cell assembly. In an exemplary embodiment, the second crossbeam 123 of the first battery assembly 120_1 can be coupled to the first crossbeam 122 of the adjacent second battery assembly 120_2. In an exemplary embodiment, the second crossbeam 123 of the second battery assembly 120_2 can be coupled to the first crossbeam 122 of the adjacent third battery assembly 120_3. In an exemplary embodiment, the second crossbeam 123 of the fourth battery assembly 120_4 can be coupled to the first crossbeam 122 of the adjacent fifth battery assembly 120_5. In an exemplary embodiment, the second crossbeam 123 of the fifth battery assembly 120_5 can be coupled with the first crossbeam 122 of the adjacent sixth battery assembly 120_6. The first crossbeam 122 and the second crossbeam 123 can connect adjacent battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 to each other. This allows the battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 to be sequentially arranged on the base plate 110B, thereby improving the assembly of the battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 to the lower frame 110.

[0047] In exemplary embodiments, the third battery assembly 120_3 and the sixth battery assembly 120_6 may include a first crossbeam 122 coupled to the first side 121S1 of the cell stack 121. The second side 121S2 of the cell stack 121 of each of the third battery assembly 120_3 and the sixth battery assembly 120_6 can be in contact with the second side plate 110S2. This allows the first crossbeam 122 of the third battery assembly 120_3 to be coupled to the second crossbeam 123 of the second battery assembly 120_2. The first crossbeam 122 of the sixth battery assembly 120_6 can be coupled to the second crossbeam 123 of the fifth battery assembly 120_5. Thus, the stability and space utilization of the battery pack 100 can be improved.

[0048] Figure 3 is a perspective view showing the first crossbeam 122 according to an exemplary embodiment.

[0049] Figure 4 is a perspective view showing a second crossbeam 123 according to an exemplary embodiment.

[0050] Figure 5 is a perspective view showing the second crossbeam 123 with the handle 123H folded according to an exemplary embodiment.

[0051] Referring to Figures 2 to 5, the first crossbeam 122 may include a first upper surface 122U and a first lower surface 122D. The first upper surface 122U and the first lower surface 122D may be substantially parallel to the upper surface 110BU of the base plate. The first lower surface 122D may be in contact with the base plate 110B, and the first upper surface 122U may be located on the opposite side from the first lower surface 122D.

[0052] The first crossbeam 122 may include a first stepped structure 122C comprising sequentially connected first bonding surfaces 122C1, second bonding surface 122C2, and third bonding surface 122C3. For example, the first upper surface 122U may be connected to the first bonding surface 122C1, and the first bonding surface 122C1 may be connected to the second bonding surface 122C2. The second bonding surface 122C2 may be connected to the third bonding surface 122C3, and the third bonding surface 122C3 may be connected to the first lower surface 122D.

[0053] In exemplary embodiments, the first crossbeam 122 may include at least one first groove 122G recessed into the second joint surface 122C2. The handle 123H of the second crossbeam 123 may be inserted into the first groove 122G of the first crossbeam 122.

[0054] Referring to Figures 2 and 3, the length of the first lower surface 122D in the X direction may be even shorter than the length of the first upper surface 122U in the X direction. The length of the first lower surface 122D in the Y direction may be substantially the same as the length of the first upper surface 122U in the Y direction. In exemplary embodiments, the second bonding surface 122C2 may be parallel to the upper surface 110BU of the base plate 110B, and the first bonding surface 122C1 and the third bonding surface 122C3 may be perpendicular to the upper surface 110BU of the base plate 110B.

[0055] In exemplary embodiments, the first bonding surface 122C1 may be substantially perpendicular to the second bonding surface 122C2. The first bonding surface may extend from the second bonding surface 122C2 in the Z direction. In exemplary embodiments, the third bonding surface 122C3 may be substantially perpendicular to the second bonding surface 122C2. The third bonding surface 122C3 may extend from the second bonding surface 122C2 in the direction opposite to the Z direction. In exemplary embodiments, the first groove 122G of the second bonding surface 122C2 may be formed in a direction away from the base plate 110B.

[0056] In exemplary embodiments, the first crossbeam 122 may include a plurality of first grooves 122G. The plurality of first grooves 122G may be arranged at regular intervals in the Y direction. The plurality of first grooves 122G may be arranged at regular intervals in a first direction parallel to the upper surface of the base plate 110B.

[0057] Referring to Figures 2 and 4, the second crossbeam 123 may include a second upper surface 123U and a second lower surface 123D. The second upper surface 123U and the second lower surface 123D may be substantially parallel to the upper surface 110BU of the base plate. The second lower surface 123D may be in contact with the base plate 110B, and the second upper surface 123U may be located on the opposite side from the second lower surface 123D. In exemplary embodiments, the length of the second lower surface 123D in the X direction may be even longer than the length of the second upper surface 123U in the X direction. The length of the second lower surface 123D in the Y direction may be substantially the same as the length of the second upper surface 123U in the Y direction.

[0058] The second crossbeam 123 may have a second stepped structure 123C including sequentially connected fourth bonding surfaces 123C1, fifth bonding surfaces 123C2, and sixth bonding surfaces 123C3. The second upper surface 123U may be connected to the fourth bonding surface 123C1, and the fourth bonding surface 123C1 may be connected to the fifth bonding surface 123C2. The fifth bonding surface 123C2 may be connected to the sixth bonding surface 123C3, and the sixth bonding surface 123C3 may be connected to the second lower surface 123D.

[0059] In exemplary embodiments, referring to Figures 2 and 4, the fifth bonding surface 123C2 may be parallel to the upper surface 110BU of the base plate 110B, and the fourth bonding surface 123C1 and the sixth bonding surface 123C3 may be perpendicular to the upper surface 110BU of the base plate 110B. In exemplary embodiments, the fourth bonding surface 123C1 may be perpendicular to the fifth bonding surface 123C2 and may extend from the fifth bonding surface 123C2 in a direction away from the base plate 110B. In exemplary embodiments, the sixth bonding surface 123C3 may be perpendicular to the fifth bonding surface 123C2 and may extend from the fifth bonding surface 123C2 in a direction toward the base plate 110B.

[0060] In an exemplary embodiment, the fifth bonding surface 123C2 may include at least one inwardly recessed second groove 123G and at least one handle 123H embedded in the second groove 123G. The second groove 123G may be formed in a direction away from the fifth bonding surface 123C2.

[0061] In exemplary embodiments, the handle 123H may be configured to rotate. The axis of rotation of the handle 123H may be substantially parallel to the first direction, i.e., the Y direction. The axis of rotation of the handle 123H may be substantially perpendicular to the second direction, i.e., the X direction. The axis of rotation of the handle 123H may be embedded in the second groove 123G, and the handle 123H may be partially embedded in the second groove 123G. A fully folded handle 123H is parallel to the fifth joint surface 123C2 and can be secured in the second groove 123G.

[0062] In exemplary embodiments, the axis of rotation of the handle 123H may be substantially parallel to the fourth joint surface 123C1. In exemplary embodiments, the axis of rotation of the handle 123H may be substantially parallel to the Y direction of the fourth joint surface 123C1, i.e., the angle in the first direction. In exemplary embodiments, the axis of rotation of the handle 123H may be substantially parallel to the sixth joint surface 123C3. In exemplary embodiments, the axis of rotation of the handle 123H may be substantially parallel to the Y direction of the sixth joint surface 123C3, i.e., the angle in the first direction.

[0063] In exemplary embodiments, as shown in Figures 4 and 5, the axis of rotation of the handle 123H may be closer to the fourth coupling surface 123C1 than to the sixth coupling surface 123C3. In this case, the extended handle 123H may be substantially perpendicular to the fifth coupling surface 123C2. The extended handle 123H can be rotated clockwise to be housed in the second groove 123G.

[0064] In an exemplary embodiment, the axis of rotation of the handle 123H may be closer to the sixth coupling surface 123C3 than to the fourth coupling surface 123C1. In this case, the extended handle 123H may be substantially perpendicular to the fifth coupling surface 123C2. The extended handle 123H can rotate counterclockwise to be housed in the second groove 123G.

[0065] Due to rotation, the handle 123H may be parallel to the second lower surface 123D or perpendicular to the second lower surface 123D. In an exemplary embodiment, the handle 123H may be parallel to the base plate 110B or perpendicular to the base plate 110B.

[0066] In an exemplary embodiment, the handle 123H is hinged to the second groove 123G, and the depth d2 of the second groove 123G may be the same as or greater than the thickness t of the handle 123H. This allows the handle 123H to be stored in the second groove 123G when folded parallel to the second lower surface 123D, thereby improving the storability of the second crossbeam 123.

[0067] In an exemplary embodiment, the second crossbeam 123 may include a plurality of second grooves 123G and a plurality of handles 123H. In an exemplary embodiment, the fifth coupling surface 123C2 may include a plurality of second grooves 123G and a plurality of handles 123H. The second grooves 123G and handles 123H can be arranged at regular intervals in the Y direction. Each of the handles 123H of the second crossbeam 123 may be coupled to a corresponding first groove 122G of the first crossbeam 122. For example, each of the handles 123H may be coupled to a first groove 122G whose Z axis overlaps with it.

[0068] Figure 6 is an enlarged partial cross-sectional view of part B in Figure 2.

[0069] Referring to Figures 2 and 6, the first crossbeam 122 and the second crossbeam 123 can overlap each other in the Z direction. The handle 123H of the second crossbeam 123 can be inserted into the first groove 122G of the first crossbeam 122. In an exemplary embodiment, the height h of the handle 123H may be substantially the same as or even lower than the depth d1 of the first groove 122G. The height h of the handle 123H can mean the length in the Z direction from the fifth coupling surface 123C2. The first crossbeam 122 and the second crossbeam 123 can be coupled while the handle 123H is inserted into the first groove 122G. In this way, the first crossbeam 122 can have a complementary shape to the second crossbeam 123. This allows the first crossbeam 122 and the second crossbeam 123 to be strongly coupled to each other without any elements for fixing the first crossbeam 122 and the second crossbeam 123 together. This improves the ease of assembly of the battery pack 100.

[0070] The first coupling surfaces 122C1 to the third coupling surfaces 122C3 of the first crossbeam 122 can be coupled to the fourth coupling surfaces 123C1 to the sixth coupling surfaces 123C3 of the second crossbeam 123. For example, the first coupling surface 122C1 can be in contact with the fourth coupling surface 123C1, the second coupling surface 122C2 can be in contact with the fifth coupling surface 123C2, and the third coupling surface 122C3 can be in contact with the sixth coupling surface 123C3.

[0071] (Second Embodiment) Figure 7 is a cross-sectional view showing a battery pack 101 according to an exemplary embodiment.

[0072] Referring to Figure 7, the battery pack 101 may include a lower frame 110' and a plurality of battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6. The lower frame 110' may include a base plate 110'B, a first side plate 110'S1 connected to the first side of the base plate 110'B, and a second side plate 110'S2 connected to the second side of the base plate 110'B. For example, the lower frame 110' may be formed as a single unit.

[0073] In an exemplary embodiment, the first side plate 110'S1 of the lower frame 110' may include a protruding structure 111 that can be inserted into a first groove 122G. The protruding structure 111 may extend in a second direction parallel to the upper surface 110'BU of the base plate, i.e., the Y direction. In an exemplary embodiment, the length of the protruding structure 111 in the Z direction may be substantially the same as the length of the first groove 122G in the Z direction. In an exemplary embodiment, the length of the protruding structure 111 in the X direction may be substantially the same as the length of the first groove 122G in the X direction. This allows the protruding structure 111 of the first side plate 110'S1 to be inserted into the first groove 122G of the first battery assembly 120_1 which is positioned on the base plate 110'B. Thus, the first battery assembly 120_1 can be easily attached to the lower frame 110'. Furthermore, since the protruding structure 111 can be checked when assembling the battery pack 100, visibility can be improved, and the ease of assembling the battery pack 101 can be improved.

[0074] In exemplary embodiments, the protruding structure 111 may have substantially the same shape as the handle 123H. For example, the thickness of the protruding structure 111 may be substantially the same as the thickness of the handle 123H. In exemplary embodiments, the length of the protruding structure 111 in the Z direction may be substantially the same as the length of the handle 123H in the Z direction.

[0075] In an exemplary embodiment, the first side plate 110'S1 of the lower frame 110' can be coupled to the first crossbeam 122 of the first battery assembly 120_1, the second crossbeam 123 of the first battery assembly 120_1 can be coupled to the first crossbeam 122 of the second battery assembly 120_2, and the second crossbeam 123 of the second battery assembly 120_2 can be coupled to the first crossbeam 122 of the third battery assembly 120_3. That is, the lower frame 110', the first battery assembly 120_1, the second battery assembly 120_2, and the third battery assembly 120_3 can interlock sequentially. This allows the battery assemblies 120_1, 120_2, 120_3, 120_4, 120_5, and 120_6 to be easily fixed to the lower frame 110', improving the ease of assembly of the battery pack 101.

[0076] (Third embodiment) Figure 8 is a cross-sectional view showing a battery pack 102 according to an exemplary embodiment.

[0077] Referring to Figure 8, the battery pack 102 may include a lower frame 110'' and several battery assemblies 120_1, 120_2, 120_3', 120_4, 120_5, and 120_6'. The lower frame 110'' may include a protruding structure 111, each of the first side plate 110''S1 and the second side plate 110''S2.

[0078] In an exemplary embodiment, the third battery assembly 120_3' may include a first crossbeam 122 coupled to the first side 121S1 of the cell stack 121 and a first crossbeam coupled to the second side 121S2 of the cell stack 121. The second side plate 110''S2 of the lower frame 110'' may include a protruding structure 111 that can be inserted into the first groove 122G. This allows the third battery assembly 120_3' to be coupled to the second battery assembly 120_2 and the second side plate 110''S2, thereby improving the coupling of the battery pack 100.

[0079] Since the sixth battery assembly 120_6' has substantially the same structure as the third battery assembly 120_3', the redundant content is omitted.

[0080] Since the protruding structure 111 of the second side plate 110''S2 has substantially the same shape as the protruding structure 111 of the first side plate 110''S1, redundant information is omitted.

[0081] <How to assemble the battery pack>

[0082] Figure 9 is a flowchart showing a method for assembling a battery pack according to an exemplary embodiment.

[0083] Figure 10 is a cross-sectional view of the first crossbeam 122 and the second crossbeam 123 according to an exemplary embodiment. Specifically, Figure 10(a) is a cross-sectional view along the cutting line C-C' showing the annular wire 200 inserted into the first crossbeam 122 of Figure 3, and Figure 10(b) is a cross-sectional view along the cutting line D-D' showing the annular wire 200 inserted into the second crossbeam 123 of Figure 4.

[0084] Referring to Figures 9 and 10, the battery pack assembly method is a step P110 of providing a first battery assembly and a second battery assembly, each of which may include a cell stack, a first crossbeam coupled to the cell stack, and a second crossbeam.

[0085] In an exemplary embodiment, the battery pack assembly method may include the steps of: assembling a first battery assembly and a second battery assembly in step P110; placing the first battery assembly 120_1 on the base plate 110B of the lower frame 110 in step P120; and placing the second battery assembly 120_2 on the base plate 110B and connecting the handle 123H of the second cross beam 123 of the first battery assembly 120_1 to the first groove 122G of the first cross beam 122 of the second battery assembly 120_2 in step P130. The lower frame 110 may include a base plate 110B, a first side plate 110S1 connected to the first side of the base plate 110B, and a second side plate 110S2 connected to the second side of the base plate 110B. The first crossbeam 122 may have a first stepped structure 122C including sequentially connected first bonding surfaces 122C1, second bonding surfaces 122C2, and third bonding surfaces 122C3. The first crossbeam 122 may include a first groove 122G recessed into the inside of the second bonding surface 122C2.

[0086] In an exemplary embodiment, step P110 for assembling the first and second battery assemblies may include the steps of transporting the first crossbeam 122 using the first groove 122G, transporting the second crossbeam 123 using the handle 123H, and coupling the first and second crossbeams 122 and 123 with the cell stack 121. For example, the first crossbeam 122 can be transported by looping an annular wire 200 over the first groove 122G. In an exemplary embodiment, referring to Figures 4, 5 and 10, the handle 123H of the second crossbeam 123 can rotate around a pivot axis 123R. The handle 123H can be folded parallel to the fifth coupling surface 123C2 and can also be extended perpendicular to the fifth coupling surface 123C2. The second crossbeam 123 can be transported by looping an annular wire 200 over the extended handle 123H. This improves the mobility of the first crossbeam 122 and the second crossbeam 123, and improves the ease of assembling the battery pack. The third battery assembly 120_3, the fourth battery assembly 120_4, the fifth battery assembly 120_5, and the sixth battery assembly 120_6 can also be assembled in the same manner.

[0087] The first side plate 110S1 may include a protruding structure 111 that can be coupled to the first groove 122G. The first battery assembly 120_1 can be positioned on the base plate 110B such that the protruding structure 111 of the first side plate 110S1 is inserted into the first groove 122G of the first cross beam 122.

[0088] In an exemplary embodiment, in step P120, in which the first battery assembly 120_1 is placed on the base plate 110B of the lower frame 110, the first battery assembly can be transported using the first groove 122G of the first crossbeam 122 and the handle 123H of the second crossbeam 123. For example, the first battery assembly 120_1 can be placed on the base plate 110B by looping the annular wire 200 around the first groove 122G and the handle 123H of the first battery assembly 120_1, respectively. The second battery assembly 120_2, the fourth battery assembly 120_4, and the fifth battery assembly 120_5 can be transported in the same manner. [Explanation of Symbols]

[0089] 100 Battery Packs 101 Battery Pack 102 Battery Pack 110 Lower frame 110' Lower Frame 110'' Lower frame 110''S1 1st Side Plate 110''S2 2nd Side Plate 110'B Baseplate 110'BU Baseplate Top 110'S1 1st Side Plate 110'S2 2nd Side Plate 110B Base Plate 110BU top Top view of 110BU to Z 110BU top 110BU Base Plate Top Surface 110S1, 110S2 Side Plates 110S1 1st Side Plate 110S1 Side Plate 110S2 2nd Side Plate 110S2 Side Plate 111 Protruding structure 120_1, 120_2, 120_3', 120_4, 120_5, 120_6' Battery Assembly 120_1, 120_2, 120_3, 120_4, 120_5, 120_6 Battery Assembly 120_1, 120_2, 120_3 Third Battery Assembly 120_1 Battery Assembly 120_1 Third Battery Assembly 120_1 First Battery Assembly 120_1 First Battery Cell Assembly 120_2 Battery Assembly 120_2 Third Battery Assembly 120_2 Second Battery Assembly 120_2 Second Battery Cell Assembly 120_3 Battery Assembly 120_3 Third Battery Assembly 120_3 Third Battery Cell Assembly 120_3' Battery Assembly 120_3' Third Battery Assembly 120_4, 120_5, 120_6 6th Battery Assembly 120_4 Battery Assembly 120_4 6th Battery Assembly 120_4 Fourth Battery Assembly 120_5 Battery Assembly 120_5 6th Battery Assembly 120_5 Fifth Battery Assembly 120_6 Battery Assembly 120_6 6th Battery Assembly 120_6' Battery Assembly 120_6' 6th Battery Assembly 121 Cell Stack 121S1 First Side 121S2 Second Side 122 First Crossbeam 122C 1st staircase structure 122C1 1st bonding surface 122C2 2nd bonding surface 122C3 3rd bonding surface 122D 1st bottom surface 122G 1st groove 122U 1st top surface 123 Second Crossbeam 123C 2nd staircase structure 123C1 4th bonding surface 123C2 5th bonding surface 123C3 6th bonding surface 123D 2nd bottom surface 123G 2nd groove 123H Handle 123R Rotation axis 123U 2nd top surface 200 annular wires A-A' cutting line Part B C-C' cutting line D-D' cutting line P110 Step P120 Step P130 Step

Claims

1. A lower frame including a base plate, a first side plate connected to the first side of the base plate, and a second side plate connected to the second side of the base plate, and A first battery assembly and a second battery assembly are arranged on the base plate. A battery pack including, Each of the first and second battery assemblies includes a cell stack comprising a plurality of battery cells and a first crossbeam coupled to a first side of the cell stack. The first crossbeam has a first stepped structure including a first connecting surface, a second connecting surface, and a third connecting surface that are sequentially connected. The battery pack includes a first crossbeam which includes a first groove recessed into the inner side of the second coupling surface.

2. The second bonding surface is parallel to the upper surface of the base plate, The first bonding surface is perpendicular to the second bonding surface, The battery pack according to claim 1, wherein the third bonding surface is perpendicular to the second bonding surface.

3. The first side plate includes a protruding structure inserted into the first groove, The battery pack according to claim 1 or 2, wherein the protruding structure extends in a first direction parallel to the upper surface of the base plate.

4. Each of the first and second battery assemblies further includes a second crossbeam coupled to the second side of the cell stack, The second side is opposite to the first side, The second crossbeam has a second stepped structure including sequentially connected fourth, fifth, and sixth bonding surfaces. The fifth bonding surface includes a second groove recessed inward and a handle partially embedded in the second groove, and The battery pack according to claim 1 or 2, wherein the handle is configured to rotate.

5. The fifth bonding surface is parallel to the upper surface of the base plate, The fourth bonding surface is perpendicular to the fifth bonding surface, and The battery pack according to claim 4, wherein the sixth bonding surface is perpendicular to the fifth bonding surface.

6. The battery pack according to claim 5, wherein the axis of rotation of the handle is parallel to the fourth coupling surface.

7. The battery pack according to claim 4, wherein the fifth coupling surface of the second crossbeam of the first battery assembly is in contact with the second coupling surface of the first crossbeam of the second battery assembly.

8. The fourth coupling surface of the second crossbeam of the first battery assembly is in contact with the first coupling surface of the first crossbeam of the second battery assembly. The battery pack according to claim 4, wherein the sixth coupling surface of the second crossbeam of the first battery assembly is in contact with the third coupling surface of the first crossbeam of the second battery assembly.

9. The battery pack according to claim 4, wherein the height of the handle of the second crossbeam is the same as or lower than the depth of the first groove of the first crossbeam.

10. The handle is hinged to the second groove, The battery pack according to claim 4, wherein the depth of the second groove is the same as or greater than the thickness of the handle.

11. Lower frame including base plate, A first battery assembly and a second battery assembly are arranged on the base plate, A battery pack including, Each of the first and second battery assemblies includes a cell stack comprising a plurality of battery cells, a first crossbeam coupled to a first side of the cell stack, and a second crossbeam coupled to a second side of the cell stack. The second side is opposite to the first side, The first crossbeam includes a plurality of first grooves that are recessed inward, The second crossbeam includes a plurality of inwardly recessed second grooves and a plurality of handles, A battery pack in which each of the plurality of handles is partially embedded in a corresponding second groove of the plurality of handles.

12. Each of the plurality of handles of the second crossbeam is coupled to a corresponding of the plurality of first grooves of the first crossbeam. The handle is configured to be rotatable by a pivot shaft, The battery pack according to claim 11, wherein the rotation axis is parallel to a first direction parallel to the upper surface of the base plate.

13. A step of providing a first battery assembly and a second battery assembly, wherein each of the first and second battery assemblies includes a cell stack, a first crossbeam coupled to the cell stack, and a second crossbeam. The steps include placing the first battery assembly on the base plate of the lower frame, The process includes the steps of placing the second battery assembly on the base plate and connecting the handle of the second crossbeam of the first battery assembly to the first groove of the first crossbeam of the second battery assembly, The lower frame includes a base plate, a first side plate connected to the first side of the base plate, and a second side plate connected to the second side of the base plate, A method for assembling a battery pack, wherein the first crossbeam includes a first groove, and the second crossbeam includes a second groove and a handle hinged to the second groove.

14. The method for assembling a battery pack according to claim 13, wherein the first battery assembly is placed on the base plate using the first groove of the first cross beam and the handle of the second cross beam.

15. The method for assembling a battery pack according to claim 13 or 14, wherein the first battery assembly is placed on the base plate such that the protruding structure of the first side plate is inserted into the first groove of the first cross beam.

Images