Battery pack

Abstract

Provided is a battery pack including: a pack case including a lower case and an upper case which define an inner space; and a plurality of cell units including a plurality of battery cells and provided in the inner space, wherein each of the cell units includes a plurality of battery cells stacked in a first direction and cell side beams provided on both sides of the plurality of stacked battery cells. The cell side beams may be coupled to a cross beam of the pack case.

Description

battery pack

[0001] The present invention relates to a battery pack, and more particularly, to a battery pack having increased productivity and improved energy density and structural rigidity.

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0120233, filed September 11, 2023, the entire disclosure of which is incorporated herein by reference.

[0003] Battery packs used in electric vehicles and other applications comprise multiple battery cells to achieve high output. Each of these battery cells, including positive and negative current collectors, separators, active materials, and electrolytes, enables repeated charging and discharging through electrochemical reactions between components.

[0004] Meanwhile, with the growing need for large-capacity structures, including their use as energy storage sources, demand is growing for battery packs, where multiple battery cells are connected in series and / or parallel and housed within a pack case. There is a growing need for ways to improve structural safety and energy density while increasing battery pack productivity.

[0005] The technical problem to be achieved by the present invention is to provide a battery pack with increased productivity and improved energy density and structural rigidity.

[0006] The present invention provides a battery pack, in order to achieve the above technical problem, comprising: a pack case including a lower case and an upper case defining an internal space; and a plurality of battery cells, the pack including a plurality of cell units provided within the internal space, each of the cell units including a plurality of battery cells stacked in a first direction and cell side beams provided on both sides of the plurality of stacked battery cells. The lower case includes a pair of side frames; a base plate coupled to a lower portion of each of the side frames; a front cover forming a front side wall of the lower case; a rear cover forming a rear side wall of the pack case; a center beam extending in the first direction; and at least one cross beam extending in a second direction perpendicular to the first direction, wherein each of the cell units is disposed within a space defined by the cross beam, the center beam, the side frames, and the front cover, or the rear cover, and the cell side beam can be coupled to the cross beam.

[0007] In some embodiments, the height of the cell side beam may be greater than the height of the cross beam.

[0008] In some embodiments, the cell side beam includes a recess, and the cross beam can be at least partially seated within the recess.

[0009] In some embodiments, the depth of the recess may be less than half the thickness of the crossbeam in the first direction.

[0010] In some embodiments, the recess can extend the entire length of the real side beam facing the cross beam in the second direction.

[0011] In some embodiments, the cell side beam may have a protrusion protruding in the first direction relative to the concave portion, and the protrusion may be configured to be coupled by interlocking the cross beam and the protruding structure.

[0012] In some embodiments, the cell side beam may have a protrusion protruding in the first direction relative to the concave portion, and the protrusion may be configured to be coupled to the cross beam by a fastener.

[0013] In some embodiments, the at least one cross beam may be welded and secured to the pair of side frames.

[0014] In some embodiments, one end of the cross beam may be welded to one of the pair of side frames, and the other end of the cross beam may be welded to the other one of the pair of side frames.

[0015] In some embodiments, the height of the cross beam may be about 40% to about 90% of the height of the side frame.

[0016] In some embodiments, each of the plurality of battery cells of the cell units may be at least partially exposed toward the upper case and / or the lower case.

[0017] Another aspect of the present invention provides a battery pack comprising: a pack case including a lower case and an upper case defining an internal space; and a plurality of battery cells, the pack including a plurality of cell units provided within the internal space, each of the cell units including a plurality of battery cells stacked in a first direction and cell side beams provided on both sides of the plurality of stacked battery cells. The lower case includes: a pair of side frames; a base plate coupled to a lower portion of each of the side frames; a front cover forming a front side wall of the lower case; a rear cover forming a rear side wall of the pack case; one center beam extending in the first direction; and at least one cross beam extending in a second direction perpendicular to the first direction, wherein each of the facing cell side beams of two neighboring cell units with the cross beam interposed therebetween includes a protrusion protruding toward each other from an upper portion of the cross beam and a concave portion capable of at least partially receiving the cross beam.

[0018] In some embodiments, the cell side beams located on both sides of the cross beam can be joined to the cross beam by bolts inserted in a third direction perpendicular to the first direction and the second direction.

[0019] In some embodiments, at least one of the cell side beams arranged on either side of a cell unit may be coupled to the front cover or the rear cover.

[0020] In some embodiments, the interior space is partitioned into four storage spaces arranged 2x2 by one center beam and one cross beam, and one cell unit can be arranged in one storage space.

[0021] The battery pack of the present invention has the effect of providing a battery pack with improved energy density and structural rigidity, with increased productivity due to a high degree of freedom in assembly.

[0022] The effects that can be obtained 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 skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing 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.

[0023] FIG. 1 is a perspective view schematically showing a battery pack according to one embodiment of the present invention.

[0024] FIG. 2 is an exploded perspective view schematically showing a battery pack according to one embodiment of the present invention.

[0025] Figure 3 is a perspective view schematically showing a cell unit accommodated in the battery pack.

[0026] Fig. 4 is a cross-sectional view showing a cross-section of a cell unit (110) cut along line A-A' of Fig. 3.

[0027] FIG. 5 is a partial cross-sectional view schematically illustrating an embodiment of the present invention in which two neighboring cell units are coupled with a crossbeam therebetween.

[0028] FIG. 6 is a partial cross-sectional view schematically illustrating an aspect in which two neighboring cell units are coupled with a crossbeam therebetween according to another embodiment of the present invention.

[0029] Figure 7 is a schematic diagram showing how a cell unit facing a front cover or a rear cover is coupled to the front cover or the rear cover.

[0030] Figure 8 is a schematic diagram showing a cross-section cut along the cross beam of Figure 2.

[0031] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the present invention may be modified in various different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. It is preferable to interpret that the embodiments of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art. Like numbers refer to like elements throughout. Furthermore, various elements and areas in the drawings are schematically drawn. Therefore, the present invention is not limited by the relative sizes or spacings depicted in the accompanying drawings.

[0032] While terms like "first" and "second" may be used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, a first component could be referred to as a "second component," and vice versa, without departing from the scope of the present invention.

[0033] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the inventive concept. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the expressions "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, operations, components, parts, or combinations thereof.

[0034] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Furthermore, it is to be understood that commonly used terms, such as those defined in dictionaries, should be interpreted to have a meaning consistent with their meaning within the relevant technical context, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0035] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0036] In the accompanying drawings, variations in the shapes depicted may be expected, for example, depending on manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention should not be construed as being limited to the specific shapes of the regions depicted herein, but should include, for example, changes in shapes resulting from the manufacturing process. All terms "and / or" used herein include each and every combination of one or more of the mentioned components. In addition, the term "substrate" used herein may mean the substrate itself, or a laminated structure including the substrate and a predetermined layer or film formed on the surface thereof. In addition, the "surface of the substrate" in this specification may mean the exposed surface of the substrate itself, or the outer surface of a predetermined layer or film formed on the substrate.

[0037]

[0038] (Example 1)

[0039] Fig. 1 is a perspective view schematically illustrating a battery pack (100) according to one embodiment of the present invention. Fig. 2 is an exploded perspective view schematically illustrating a battery pack (100) according to one embodiment of the present invention. Fig. 3 is a perspective view schematically illustrating a cell unit (110) accommodated within the battery pack (100).

[0040] In FIGS. 1 to 3, the battery pack (100) is illustrated as being defined in a vertical coordinate system defined by a first direction along the x-axis, a second direction along the y-axis, and a third direction along the z-axis, which are all perpendicular to each other, but the first direction, the second direction, and the third direction are not particularly limited as long as they are relatively perpendicular to each other.

[0041] Referring to FIGS. 1 to 3, a battery pack (100) according to one embodiment of the present invention may include a pack case (120) having at least one cell unit (110) and an internal space for accommodating at least one of the cell units (110).

[0042] In some embodiments, the cell units (110) may be configured to form a battery module in which the battery cells are accommodated within a module frame, and the battery module may be accommodated within the internal space. Although the battery cells (111) are described below as being accommodated directly within the internal space of the pack case (120) rather than within the module frame, those skilled in the art will understand that the same may be applied to a case in which the battery cells are configured as a battery module.

[0043] The battery cell (111) may be, for example, a pouch-type battery cell with high energy density and easy stacking, or a square or cylindrical battery cell. The following description will focus on the case where the battery cell (111) is in a pouch shape, but those skilled in the art will understand that the same description may also be applied to the case where the battery cell (111) is in a square or cylindrical shape.

[0044] The above plurality of battery cells (111) can be electrically connected to each other through bus bars provided in a bus bar frame (112) and accommodated in the pack case (120), and can be fixed to the bottom surface of the pack case (120) by, for example, a heat-dissipating resin layer.

[0045] The pack case (120) may include a component for forming a space capable of storing cell units (110), a pair of side frames (121, 122), a base plate (126) coupled to the lower portions of each of the pair of side frames (121, 122), a top plate (125) coupled to the upper portions of each of the side frames (121, 122), a front cover (124) forming the front wall of the pack case (120), and a rear cover (123) forming the rear wall.

[0046] In some embodiments, the top plate (125) may constitute an upper case, and the base plate (126), side frames (121, 122), front cover, and rear cover (123) may constitute a lower case.

[0047] For example, as illustrated in FIG. 2, the pack case (120) may include a first side frame (121) located on the left side and a second side frame (122) located on the right side with respect to the base plate (126). That is, the first side frame (121) may be coupled to the left end of the base plate (126). The second side frame (122) may be coupled to the right end of the base plate (126).

[0048] In some embodiments, the pack case (120) may further include a gas venting unit (130). In some embodiments, the gas venting unit (130) of the battery pack (100) may be provided on the inside of the internal space of the pack case (120). The gas venting unit (130) may have an overall plate shape. The gas venting unit (130) may be configured to rupture at least a portion thereof when the internal gas pressure of the pack case (120) becomes a predetermined level or higher.

[0049] The above gas venting unit (130) may be configured so that, when a portion thereof is ruptured as described above, gas in the internal space flows into the gas inlet. That is, when a portion of the gas venting unit (130) is ruptured, the internal gas pressure of the pack case (120) is greater than the external atmospheric pressure of the pack case, so that the gas in the internal space of the pack case (120) moves along the gas discharge path, and the gas can be discharged to the outside through the venting device (150) of the rear cover (123) and the front cover (124) through the gas discharge port at the end of the gas discharge path.

[0050] To this end, the rear cover (123) and the front cover (124) may have a flow path through which gas can flow, similar to the first side frame (121) and the second side frame (122). The flow paths of the rear cover (123) and the front cover (124) may be in fluid communication with the gas discharge path and gas discharge port formed inside the side frames (121, 122).

[0051] The flow paths of the rear cover (123) and the front cover (124) are in fluid communication with the venting device (150), so that gas can be discharged through the venting device (150).

[0052] The above cell unit (110) may include a plurality of battery cells (111) stacked in a first direction (e.g., in the x-axis direction), and cell side beams (113) may be provided on both sides of the plurality of battery cells (111) in the first direction. As described above, the plurality of battery cells (111) may be electrically connected to each other through a bus bar provided within a bus bar frame (112).

[0053] Fig. 4 is a cross-sectional view showing a cross-section of a cell unit (110) cut along line A-A' of Fig. 3.

[0054] Referring to FIGS. 3 and 4, cell side beams (113) are provided on both sides of a plurality of battery cells (111) stacked in a first direction (e.g., x-axis direction).

[0055] In some embodiments, the battery cells (111) may have a thin plate-shaped body, and may preferably be configured as a pouch cell structure. The pouch cell may be configured as a structure in which a positive electrode, a separator, and a negative electrode are alternately stacked to form the electrode assembly, and an electrode tab is extended to at least one side and connected to the cell lead. The positive and negative electrodes may be manufactured by applying a slurry of an electrode active material, a binder resin, a conductive agent, and other additives to at least one surface of a current collector. For the positive electrode, a typical positive electrode active material such as a lithium-containing transition metal oxide may be used, and for the negative electrode, a typical negative electrode active material such as lithium metal, carbon material, and metal compound or a mixture thereof capable of absorbing and releasing lithium ions may be used. In addition, a typical porous polymer film used in a lithium secondary battery may be employed as the separator.

[0056] As the electrolyte accommodated in the cover together with the electrode assembly, a typical lithium secondary battery electrolyte may be employed. The cover is formed of a sheet material and has a receiving portion for accommodating the electrode assembly. Preferably, the cover is formed by combining a first case and a second case, which are formed by processing a sheet material into a predetermined shape. The sheet material constituting the cover has a multilayer structure in which an outermost outer resin layer made of an insulating material such as polyethylene terephthalate (PET) or nylon is laminated, a metal layer made of aluminum that maintains mechanical strength and prevents the penetration of moisture and oxygen, and an inner resin layer made of a polyolefin-based material that has thermal adhesive properties and serves as a sealant.

[0057] The sheet material forming the above cover may have a predetermined adhesive resin layer interposed between the inner resin layer and the metal layer, and between the outer resin layer and the metal layer, as needed. The adhesive resin layer is formed as a single layer or multiple layers for smooth adhesion between different materials, and the material is typically a polyolefin resin, or a polyurethane resin may be used for smooth processing, and a mixture of these may also be employed.

[0058] In some embodiments, the cell side beams (113) may be supported by being fixed to the busbar frame (112).

[0059] The plurality of battery cells (111) included in each cell unit (110) may be at least partially exposed toward the top plate (125) and / or the base plate (126) of the pack case (120). In some embodiments, the cell side beams (113) may serve as a module frame while extending along the upper or lower surface of the plurality of battery cells (111). In some embodiments, the cell side beams (113) may not always completely surround the plurality of battery cells (111) while serving as the module frame. In this case, the plurality of battery cells (111) may be at least partially exposed toward the top plate (125) and / or the base plate (126) of the pack case (120).

[0060] In some embodiments, the cell side beams (113) may not extend along the upper surfaces of the plurality of battery cells (111). In some embodiments, the cell side beams (113) may not extend along the lower surfaces of the plurality of battery cells (111). In some embodiments, the cell side beams (113) may not extend along either the upper or lower surfaces of the plurality of battery cells (111).

[0061] In some embodiments, the cell side beam (113) may include a recess (1133) that at least partially accommodates the cross beam (128), as described below. In some embodiments, the cell side beam (113) may have a protrusion (1131) that protrudes in the first direction relative to the recess (1133).

[0062] The above concave portion (1133) may have a first height (H1) in a third direction (e.g., in the Z-axis direction). The first height (H1) may be substantially the same as the height of the cross beam (128) described later. Therefore, the height of the cell side beam (113) in the third direction is greater than the height of the cross beam (128).

[0063] The above concave portion (1133) can extend in the longitudinal direction (e.g., Y-axis direction) of the cell side beam (113).

[0064] FIG. 5 is a partial cross-sectional view schematically illustrating an aspect in which two neighboring cell units (110a, 110b) are coupled with a crossbeam (128) therebetween according to one embodiment of the present invention.

[0065] Referring to FIGS. 4 and 5, the first cell unit (110a) is adjacent to the second cell unit (110b) with the cross beam (128) therebetween. The first cell side beam (113a) of the first cell unit (110a) faces the second cell side beam (113b) of the second cell unit (110b) with the cross beam (128) therebetween. The first cell side beam (113a) and the second cell side beam (113b) have cross sections that are symmetrical with respect to each other in the first direction (e.g., the X-axis direction).

[0066] The first cell side beam (113a) has a first concave portion (1133a), and the second cell side beam (113b) has a second concave portion (1133b). The cross beam (128) can be positioned within a space defined by the first concave portion (1133a) and the second concave portion (1133b).

[0067] Although FIG. 5 illustrates that the convex portion of the first cell side beam (113a) and the convex portion of the second cell side beam (113b) are in contact with each other, the present invention is not limited thereto. In some embodiments, the depth (d1) of the concave portion (1133) (see FIG. 4) may be less than half the thickness of the cross beam (128) in the first direction (e.g., X-axis direction), in which case the convex portion of the first cell side beam (113a) and the convex portion of the second cell side beam (113b) may not be in contact with each other.

[0068] The side surface of the cross beam (128) can be in contact with the side surface of the first cell side beam (113a) and the second cell side beam (113b) forming the concave portions (1133a, 1133b).

[0069] The first cell side beam (113a) and the second cell side beam (113b) may be coupled to the cross beam (128) by a fastener such as a bolt (B). To this end, a through hole (1135) may be formed in each of the first cell side beam (113a) and the second cell side beam (113b). The through hole (1135) may be formed in a convex portion of each of the first cell side beam (113a) and the second cell side beam (113b). The through hole (1135) may extend in a third direction (e.g., the Z-axis direction). A fastening hole may be provided in the cross beam (128) to which a fastener inserted through the through hole (1135) may be coupled. The bolt (B) may extend through the through hole (1135) to the fastening hole provided in the cross beam (128).

[0070] The above-described recesses (1133a, 1133b) can extend in the longitudinal direction of the cell side beams (113a, 113b) over the entire length of the cell side beams (113a, 113b) facing the cross beam (128). In other words, the above-described recesses (1133a, 1133b) can extend in the second direction (e.g., the Y-axis direction) over the entire length of the cell side beams (113a, 113b).

[0071] The lower surface of the convex portion (1131u) forming a step between the convex portion (1131) and the concave portion (1133) can be in close contact with the upper surface of the cross beam (128).

[0072] In Fig. 5, the cross beam (128) and the cell side beams (113a, 113b) are shown to be connected by a fastener such as a bolt (B), but the present invention is not limited thereto. Fig. 6 is a partial cross-sectional view schematically showing an aspect in which two neighboring cell units (110a, 110b) are connected with the cross beam (128) interposed therebetween according to another embodiment of the present invention.

[0073] Referring to FIG. 6, the cross beam (128a) may have a protruding structure (128p) that can be coupled with the cell side beams (113a, 113b). In addition, the cell side beams (113a, 113b) may have a complementary protruding structure that can be interlocked with the protruding structure (128p) of the cross beam (128a).

[0074] In some embodiments, as illustrated in FIG. 6, the cross beam (128a) may have a convex portion protruding toward the lower surface of the protrusions of the cell side beams (113a, 113b), and the cell side beams (113a, 113b) may have a concave portion capable of receiving the convex portion. Those skilled in the art will understand that an interlocking connection may be achieved by having a convex portion protruding toward the cross beam (128a) on the lower surface of the protrusions of the cell side beams (113a, 113b), and having a concave portion capable of receiving the convex portion on the upper surface of the cross beam (128a).

[0075] Since the cell side beams (113) are directly connected to the cross beams (128), structural rigidity can be increased. In addition, since there are no restrictions on the assembly order due to the cross-sectional shape of the cell side beams (113), high productivity can be achieved.

[0076]

[0077] (Example 2)

[0078] Referring again to FIG. 2, the pack case (120) of the battery pack (100) may have one center beam (127) and one cross beam (128). The internal space may be divided into four storage spaces arranged in a 2x2 arrangement by the center beam (127) and the cross beam (128). Furthermore, each of the four storage spaces may accommodate one cell unit (110).

[0079] In this embodiment, since only one cross beam (128) is provided, the efficiency of the internal space is increased, thereby increasing the energy density of the battery pack (100).

[0080] The manner in which the cell unit (110) is coupled to the cross beam (128) is as described above with reference to FIGS. 5 and 6. The cell unit (110) faces the front cover (124) or the rear cover (123) on the side that does not face the cross beam (128).

[0081] Figure 7 is a schematic diagram showing how a cell unit (110) facing a front cover (124) or a rear cover (123) is coupled to the front cover (124) or the rear cover (123).

[0082] Referring to FIG. 7, the front cover (124) or the rear cover (123) may have a protrusion corresponding to the concave portion (1133) of the cell side beam (113). In some embodiments, the cell side beam (113) may be coupled to the front cover (124) or the rear cover (123) by a fastener such as a bolt (B). To this end, a through hole may be formed in the cell side beam (113) as illustrated in FIG. 4, and a fastening hole may be provided in the front cover (124) or the rear cover (123) at a position corresponding to the through hole.

[0083] The above bolt (B) can be extended through the through hole to the fastening hole of the front cover (124) or rear cover (123), thereby connecting the cell side beam (113) and the front cover (124) or rear cover (123) to each other.

[0084] Although FIG. 7 illustrates an example of connecting the cell side beam (113) and the front cover (124) or the rear cover (123) using a fastener such as a bolt (B), a person skilled in the art will understand that the cell side beam (113) and the front cover (124) or the rear cover (123) can be connected to each other by an interlocking connection using a protruding structure as in the embodiment described with reference to FIG. 6.

[0085] In some embodiments, the pack case (120) may further include an additional cross beam adjacent to the front cover (124) or the rear cover (123). In this case, the cell side beam (113) may be coupled with the additional cross beam. In this case, the structural burden of the front cover (124) or the rear cover (123) may be alleviated because the mechanical load generated by the cell unit (110) is transferred to the additional cross beam.

[0086]

[0087] Fig. 8 is a schematic diagram showing a cross-section cut along the cross beam (128) of Fig. 2.

[0088] Referring to FIG. 8, the cross beam (128) can be welded and joined to a pair of side frames (121, 122). That is, one end of the cross beam (128) can be welded and joined to one of the pair of side frames (121, 122), and the other end of the cross beam (128) can be welded and joined to the other of the pair of side frames (121, 122).

[0089] Previously, since the cross beam (128) was connected to the side frames (121, 122) by bolt connection, through holes for bolt connection were provided on the side surfaces of the side frames corresponding to the cross beam (128).

[0090] Since the cross beam (128) is joined to the side frames (121, 122) by welding, there are no through holes on the side surfaces of the side frames (121, 122), and therefore, the penetration of foreign substances such as moisture through the through holes can be prevented.

[0091] In some embodiments, the cross beam (128) may have a notch portion (N) for coupling with a center beam (127). The center beam (127) may extend in the visual direction past the notch portion (N) illustrated in FIG. 8. The cross beam (128) and the center beam (127) may interlock with each other in a third direction (e.g., in the Z-axis direction) at a portion where they intersect each other.

[0092] The height of the cross beam (128) in the third direction (e.g., Z-axis direction) may be about 40% to about 90% of the height of the side frames (121, 122). If the height of the cross beam (128) is excessively low, it may not be able to sufficiently support the cell units (110). If the height of the cross beam (128) is excessively high, it may become difficult to secure the cell side beams (113) to the cross beam (128).

[0093] In some embodiments, the height of the cross beam (128) in the third direction (e.g., the Z-axis direction) may be about 40% to about 90%, about 45% to about 85%, about 50% to about 80%, about 55% to about 75%, about 60% to about 70%, or a range between any two of these values, of the height of the side frames (121, 122).

[0094]

[0095] While the embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, modifications to future embodiments of the present invention will not depart from the scope of the invention.

[0096]

[0097] [Explanation of symbols]

[0098] 100: Battery pack

[0099] 110, 110a, 110b: Cell Unit

[0100] 111: Battery cell

[0101] 112: Busbar frame

[0102] 113, 113a, 113b: Cell side beams

[0103] 120: Pack Case

[0104] 121, 122: Side frame

[0105] 123: Rear cover

[0106] 124: Front cover

[0107] 125: Top plate

[0108] 126: Base Plate

[0109] 127: Center beam

[0110] 128, 128a: Cross beam

[0111] 1131: Protrusion

[0112] 1133, 1133a, 1133b: concave

[0113] 1135: Through hole

Claims

1. A pack case including a lower case and an upper case defining an internal space; and A plurality of cell units comprising a plurality of battery cells and provided within the internal space; Including, Each of the above cell units includes a plurality of battery cells stacked in a first direction and cell side beams provided on both sides of the plurality of stacked battery cells, The above lower case: A pair of side frames; A base plate coupled to the lower portion of each of the above side frames; A front cover forming the front side wall of the lower case; A rear cover forming the rear side wall of the above pack case; a center beam extending in the first direction; and At least one cross beam extending in a second direction perpendicular to the first direction; Including, Each of the above cell units is arranged within a space defined by the cross beam, the center beam, the side frames, and the front cover or the rear cover, The above cell side beam is a battery pack coupled to the above cross beam.

2. In paragraph 1, A battery pack characterized in that the height of the cell side beam is greater than the height of the cross beam.

3. In paragraph 1, The above cell side beam includes a concave portion, A battery pack, wherein the crossbeam is at least partially seated within the recess.

4. In paragraph 3, A battery pack, characterized in that the depth of the above concave portion is less than half the thickness of the first direction of the crossbeam.

5. In paragraph 3, A battery pack characterized in that the concave portion extends over the entire length of the real side beam facing the cross beam in the second direction.

6. In paragraph 3, A battery pack characterized in that the cell side beam has a protrusion that protrudes in the first direction compared to the concave portion, and the protrusion is configured to be coupled by interlocking the cross beam and the protruding structure.

7. In paragraph 3, A battery pack characterized in that the cell side beam has a protrusion that protrudes in the first direction compared to the concave portion, and the protrusion is configured to be connected to the cross beam by a fastener.

8. In paragraph 1, A battery pack in which at least one cross beam is welded and fixed to the pair of side frames.

9. In paragraph 8, A battery pack, characterized in that one end of the cross beam is welded to one of the pair of side frames, and the other end of the cross beam is welded to the other of the pair of side frames.

10. In paragraph 8, A battery pack characterized in that the height of the cross beam is 40% to 90% of the height of the side frame.

11. In paragraph 1, A battery pack, wherein each of the plurality of battery cells of the cell units is at least partially exposed toward the upper case and / or the lower case.

12. A pack case comprising a lower case and an upper case defining an internal space; and A plurality of cell units comprising a plurality of battery cells and provided within the internal space; Including, Each of the above cell units includes a plurality of battery cells stacked in a first direction and cell side beams provided on both sides of the plurality of stacked battery cells, The above lower case: A pair of side frames; A base plate coupled to the lower portion of each of the above side frames; A front cover forming the front side wall of the lower case; A rear cover forming the rear side wall of the above pack case; one center beam extending in the first direction; and At least one cross beam extending in a second direction perpendicular to the first direction; Including, Each of the facing cell side beams of two neighboring cell units with the above cross beam in between: Protrusions protruding toward each other from the upper portion of the above cross beams; and A recess capable of at least partially accommodating the cross beam; Battery pack containing.

13. In paragraph 12, A battery pack characterized in that the cell side beams located on both sides of the cross beam are connected to the cross beam by bolts inserted in a third direction perpendicular to the first direction and the second direction.

14. In paragraph 12, A battery pack characterized in that at least one of the cell side beams arranged on both sides of one cell unit is coupled to the front cover or the rear cover.

15. In paragraph 12, The above interior space is divided into four storage spaces arranged 2x2 by one center beam and one cross beam, A battery pack characterized by having one cell unit arranged in one storage space.

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