Battery module and battery pack including the same

Abstract

A battery module according to an embodiment of the present invention includes: a battery cell stack in which a plurality of battery cells are stacked along a first direction; at least one vertical beam disposed at least at one of both side surfaces of the battery cell stack or between the battery cells in the battery cell stack; at least one first cover member located on one side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction; and at least one second cover member located on the other side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction. When viewed along a height direction perpendicular to the first direction, the first cover member and the second cover member are located in a region where they do not overlap each other.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0184467 filed on December 26, 2022 and Korean Patent Application No. 10 - 2023 - 0183617 filed on December 15, 2023, and all of the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a battery module and a battery pack including the same, and more specifically, to a battery module with improved energy density and a battery pack including the same.

Background Art

[0003] In modern society, the use of portable devices such as mobile phones, laptops, video cameras, and digital cameras has become common, and the development of technologies in fields related to such mobile devices has become active. In addition, rechargeable secondary batteries are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug - in hybrid electric vehicles (P - HEVs), etc. as a solution to problems such as air pollution in existing gasoline vehicles that use fossil fuels, and the need for the development of secondary batteries is increasing.

[0004] Current commercially available secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, nickel - zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries have attracted attention for their advantages of almost no memory effect compared to nickel - based secondary batteries, free charge and discharge, very low self - discharge rate, and high energy density.

[0005] Such a lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such positive electrode active material and negative electrode active material are arranged with a separator therebetween, and a battery case for hermetically storing the electrode assembly together with an electrolytic solution.

[0006] Generally, lithium secondary batteries can be classified into a can-type secondary battery in which an electrode assembly is installed in a metal can and a pouch-type secondary battery in which an electrode assembly is installed in a pouch of an aluminum laminate sheet according to the shape of the exterior material.

[0007] In the case of a secondary battery used for small devices, 2-3 battery cells are arranged. However, in the case of a secondary battery used for medium and large-sized devices such as automobiles, a battery module in which a number of battery cells are electrically connected is used. In such a battery module, a number of battery cells are connected in series or in parallel with each other to form a battery cell laminate, thereby improving the capacity and output. In addition, one or more battery modules can be mounted together with various control and protection systems such as a BDU (Battery Disconnect Unit), a BMS (Battery Management System), and a cooling system to form a battery pack.

[0008] Unlike the battery pack mounted on a passenger car, the battery pack mounted on a commercial vehicle can be located in the empty space at the lower part of the cargo loading space instead of the user's seat. Thus, a battery pack with a relatively high height is required.

[0009] When constructing a high - height battery pack with a normal battery module, unnecessary space loss occurs due to factors such as duplication of components arranged between battery modules, assembly tolerances, and space for allowing swelling. Therefore, it is necessary to develop a battery module and a battery pack with a novel structure that can suppress displacement due to swelling of battery cells in the battery module, minimize the internal space lost at the same time, and increase the energy density.

Summary of the Invention

Problems to be Solved by the Invention

[0010] The problem to be solved by the present invention is to provide a battery module and a battery pack including the same, which can suppress displacement due to swelling of battery cells in the battery module, minimize the internal space lost at the same time, and increase the energy density.

[0011] However, the problems to be solved by the embodiments of the present invention are not limited to the above - mentioned problems, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0012] A battery module according to an embodiment of the present invention includes: a battery cell stack in which a plurality of battery cells are stacked along a first direction; at least one vertical beam disposed on both side surfaces of the battery cell stack or at least one location between the battery cells in the battery cell stack; at least one first cover member located on one side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction; and at least one second cover member located on the other side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction. When viewed along a height direction perpendicular to the first direction, the first cover member and the second cover member are located in a region where they do not overlap each other.

[0013] At least one of the first cover members can be located on one side of the battery cell stack along the height direction, and at least one of the second cover members can be located on the other side of the battery cell stack along the height direction.

[0014] At least one of the first cover members and at least one of the second cover members can be located on opposite sides of each other with the battery cell stack therebetween.

[0015] At least one of the first cover member or the second cover member may be in the form of a plate having a hollow inside.

[0016] The second cover member can be located at the lower part of the battery cell stack and may be in the form of a plate having a hollow inside.

[0017] The first cover member and the second cover member can each be composed of a plurality. Each of the plurality of first cover members and the plurality of second cover members can be arranged spaced apart along a second direction perpendicular to both the first direction and the height direction.

[0018] When viewed along the height direction, any one of the first cover members can be located in the region between the second cover members.

[0019] When viewed along the height direction, any one of the second cover members can be located in the region between the first cover members.

[0020] A battery pack according to an embodiment of the present invention includes a plurality of the battery modules, and at least two of the battery modules are stacked along the height direction. The battery module includes a first battery module and a second battery module that are adjacent to each other along the height direction. The second cover member of the first battery module and the first cover member of the second battery module are located in a space between the battery cell stack of the first battery module and the battery cell stack of the second battery module.

[0021] In the battery module, the first cover member and the second cover member may each be configured by a plurality. Each of the plurality of first cover members and the plurality of second cover members may be spaced apart and arranged along a second direction perpendicular to both the first direction and the height direction.

[0022] Along the second direction perpendicular to both the first direction and the height direction, the second cover member of the first battery module and the first cover member of the second battery module can be alternately positioned.

[0023] The battery pack may further include a long bolt member that penetrates all of the vertical beams of the battery modules stacked along the height direction and is fixed to a vehicle or a pack frame.

Advantages of the Invention

[0024] According to an embodiment of the present invention, by positioning the first cover member and the second cover member of the battery module in non-overlapping regions with respect to each other, the total height when the battery modules are stacked along the height direction can be reduced. That is, the space can be reduced and the energy density can be increased.

[0025] Also, by fixing the battery modules stacked in the height direction with a long bolt member that penetrates the vertical beams of the battery modules, the structural safety of the battery pack can be enhanced, and at the same time, the displacement due to the swelling of the battery cells inside the battery module can be effectively suppressed.

[0026] The effects of the present invention are not limited to the above effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Brief Description of the Drawings

[0027]

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Figure 11

Modes for Carrying Out the Invention

[0028] Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those skilled in the art to which the present invention pertains can easily implement it. The present invention can be implemented in several different forms and is not limited to the embodiments described herein.

[0029] To clearly explain the present invention, parts not related to the explanation are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

[0030] In addition, the sizes and thicknesses of the respective configurations shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to what is shown in the drawings. In the drawings, the thickness is enlarged to clearly represent a plurality of layers and regions. And, in the drawings, for convenience of explanation, the thicknesses of some layers and regions are exaggerated.

[0031] Also, when a part such as a layer, film, region, or plate is "on" or "above" another part, this includes not only the case where it is "directly above" the other part but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in the middle. Also, being "on" or "above" the reference part means being located above or below the reference part, and does not necessarily mean being located "up" or "above" in the direction opposite to gravity.

[0032] Also, throughout the specification, when a part "includes" a certain component, it means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0033] Also, throughout the specification, "on a plane" means when the target part is viewed from above, and "in a cross-section" means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0034] FIG. 1 is a schematic perspective view of a battery module according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a cross-section cut along the cutting line A-A' of FIG. 1. FIG. 3 is a perspective view showing one of the battery cells included in the battery module of FIGS. 1 and 2. FIG. 4 is a perspective view showing a state in which a first cover member is removed from the battery module of FIG. 1.

[0035] Referring to FIGS. 1 to 4, a battery module 100 according to an embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked along a first direction (d1); at least one vertical beam 200 disposed on both side surfaces of the battery cell stack 120 or at least one location between the battery cells 110 in the battery cell stack 120; at least one first cover member 300 located on one side of the battery cell stack 120, connected to at least one vertical beam 200, and extending along the first direction (d1); and at least one second cover member 400 located on the other side of the battery cell stack 120, connected to at least one vertical beam 200, and extending along the first direction (d1).

[0036] The battery cell 110 according to the present embodiment may be a battery cell in various forms. For example, it may be a pouch-type battery cell, a square battery cell, or a cylindrical battery cell. As an example, as shown in FIG. 3, the battery cell 110 according to the present embodiment may be a pouch-type battery cell. Hereinafter, the pouch-type battery cell will be described, but the battery cell 110 according to the present embodiment is not limited thereto, and various types of battery cells may be applied. The pouch-type battery cell can be formed by housing an electrode assembly in a pouch case, which is a laminate sheet including a resin layer and a metal layer, and then adhering the outer peripheral portion of the pouch case. The battery cell 110 can have a rectangular sheet structure. For example, the battery cell 110 according to the present embodiment can have a structure in which two electrode leads 130 protrude from one end and the other end facing each other. One of the electrode leads 130 is a positive electrode lead, and the other is a negative electrode lead.

[0037] In particular, referring to FIG. 3, the battery cell 110 according to this embodiment has a structure in which two electrode leads 130 protrude from one end portion 114a and the other end portion 114b of the cell body 113 facing each other. More specifically, the electrode lead 130 is connected to an electrode assembly (not shown) and protrudes from the electrode assembly (not shown) to the outside of the battery cell 110.

[0038] On the other hand, the battery cell 110 can be manufactured by adhering both end portions 114a and 114b of the cell case 114 and one side portion 114c connecting them in a state where an electrode assembly (not shown) is housed in the cell case 114. That is, the battery cell 110 according to this embodiment has a total of three sealing portions 114sa, 114sb, and 114sc, and the sealing portions 114sa, 114sb, and 114sc are structured to be sealed by a method such as heat fusion, and the other remaining side can be constituted by a folding portion 115. The cell case 114 can be constituted by a laminate sheet including a resin layer and a metal layer.

[0039] Although FIG. 3 only describes the battery cell 110 having a structure in which the electrode leads 130 protrude in both directions, as another embodiment of the present invention, it goes without saying that a one-way pouch-type battery cell in which the electrode leads protrude together in one direction is also possible.

[0040] The cell case 114 of the laminate sheet can include an inner resin layer for sealing, a metal layer for preventing the penetration of substances, and an outermost outer resin layer. Based on the electrode assembly inside the cell case 114, the inner resin layer can be located innermost, the outer resin layer can be located outermost, and the metal layer can be located between the inner resin layer and the outer resin layer.

[0041] The outer resin layer can have excellent tensile strength and weather resistance in terms of thickness ratio and can have electrical insulation properties to protect the electrode assembly from the outside. Such an outer resin layer can include polyethylene terephthalate (PET) resin or nylon resin. The metal layer can prevent air, moisture, etc. from flowing into the pouch-type secondary battery. Such a metal layer can include aluminum (Al). The inner resin layer can be heat-sealed by the heat and / or pressure applied with the electrode assembly built in. Such an inner resin layer can include casted polypropylene (CPP) or polypropylene (PP).

[0042] The cell case 114 can be divided into two parts, and a concave storage part where the electrode assembly can be placed can be formed in at least one of the two parts. Along the outer periphery of such a storage part, the inner resin layers of the two parts of the cell case 114 can be joined to each other to provide sealing parts 114sa, 114sb, 114sc. The pouch case is sealed in such a manner to manufacture the battery cell 110.

[0043] Such battery cells 110 can be composed of a plurality, and the plurality of battery cells 110 can be stacked so as to be electrically connected to each other to form a battery cell stack 120. In particular, the battery cells 110 can be stacked along the first direction (d1) while standing upright with one surface of the cell body 113 facing each other to form a battery cell stack 120. Thereby, one electrode lead 130 of the battery cell 110 can protrude in the second direction (d2) described later, and the other electrode lead 130 can protrude in the direction opposite to the second direction (d2).

[0044] The vertical beam 200 is a plate-like member having a constant area and can be arranged parallel to the one surface of the battery cell 110. The vertical beam 200 can be arranged parallel to one surface of the cell body 113 of the battery cell 110. That is, one surface of the vertical beam 200 can be orthogonal to the first direction (d1) in which the battery cells 110 are stacked. As will be described later, such a vertical beam 200 can control the displacement due to the swelling of the battery cell 110. As described above, the vertical beam 200 is arranged on at least one of both side surfaces of the battery cell stack 120 or between the battery cells 110 in the battery cell stack 120. As an example, a plurality of vertical beams 200 may be respectively arranged so as to cover both side surfaces of the battery cell stack 120 from the outside of the battery cell stack 120. Also, the vertical beam 200 can be located between the battery cells 110 in the battery cell stack 120. FIGS. 1 to 4 show a total of four vertical beams 200, two vertical beams 200 located on both side surfaces of the battery cell stack 120 and two vertical beams 200 located between the battery cells 110. For structural stability, it is preferable to provide the vertical beam 200 that covers both side surfaces of the battery cell stack 120 from the outside of the battery cell stack 120. On the other hand, the number of the vertical beams 200 located between the battery cells 110 in the battery cell stack 120 is not particularly limited and can be determined in consideration of the number and size of the battery cells 110 and the like.

[0045] The battery cell stack 120 can be divided into a plurality of sub-battery cell stacks 120a, 120b, 120c by the vertical beam 200 arranged between the battery cells 110. As an example, the battery cell stack 120 can include first to third sub-battery cell stacks 120a, 120b, 120c partitioned by two vertical beams 200. One of the vertical beams 200 can be located between the first sub-battery cell stack 120a and the second sub-battery cell stack 120b, and the other vertical beam 200 can be located between the second sub-battery cell stack 120b and the third sub-battery cell stack 120c.

[0046] FIG. 5 is a perspective view showing a vertical beam and a second cover member included in the battery module of FIG. 1. FIG. 6 is a perspective view showing a vertical beam and a first cover member included in the battery module of FIG. 1. FIG. 7 is a bottom view of the battery module of FIG. 1 as viewed from below. FIG. 8 is a plan view of the battery module of FIG. 1 as viewed from above.

[0047] Referring to FIGS. 1, 2, 5 to 8 together, in the battery module 100 according to the present embodiment, when viewed along the height direction (dh) perpendicular to the first direction (d1), the first cover member 300 and the second cover member 400 are located in regions where they do not overlap each other.

[0048] Each of the first cover member 300 and the second cover member 400 according to the present embodiment is connected to the vertical beam 200 and extends along the first direction (d1) which is the direction in which the battery cells 110 are stacked. Specifically, at least one first cover member 300 can be located on one side of the battery cell stack 120 along the height direction (dh), and at least one second cover member 400 can be located on the other side of the battery cell stack 120 along the height direction (dh). In particular, at least one first cover member 300 and at least one second cover member 400 can be located on opposite sides of each other with the battery cell stack 120 therebetween. As an example, as shown in FIGS. 1, 2, 5 and 6, the first cover member 300 can be located above the battery cell stack 120, and the second cover member 400 can be located below the battery cell stack 120. In other embodiments of the present invention, it is also possible that the first cover member is located below the battery cell stack 120 and the second cover member is located above the battery cell stack 120.

[0049] When viewed along the height direction (dh), since the first cover member 300 and the second cover member 400 are located in a region where they do not overlap each other, when a plurality of battery modules 100 are stacked along the height direction (dh), the second cover member 400 of the battery module 100 located above and the first cover member 300 of the battery module 100 located below can be located in a region where they do not overlap each other. In another embodiment where the first cover member is located at the lower part of the battery cell stack 120 and the second cover member is located at the upper part of the battery cell stack 120, the first cover member of the battery module 100 located above and the second cover member of the battery module 100 located below can be positioned without overlapping each other. In this embodiment, the first cover member 300 and the second cover member 400 are set so as not to overlap each other, and the total height when the battery modules 100 are stacked along the height direction (dh) can be reduced. This will be described later.

[0050] On the other hand, in the battery module 100, the first cover member 300 and the second cover member 400 can each be configured by a plurality. Each of the plurality of first cover members 300 and the plurality of second cover members 400 can be arranged at intervals along a second direction (d2) perpendicular to both the first direction (d1) and the height direction (dh). In this specification, the first direction (d1), the second direction (d2), and the height direction (dh) are directions referred to for convenience of explanation and are directions that are perpendicular to each other in all respects. As an example, embodiments in which the battery module 100 has two first cover members 300 and three second cover members 400, and each of the two first cover members 300 and the three second cover members 400 are located at intervals along the second direction (d2) are shown in FIGS. 1, 5 to 8.

[0051] Also, when viewed along the height direction (dh), any one of the first cover members 300 can be located in the region (A2, see FIG. 5) between the second cover members 400. Specifically, a region (A2) having a vacant space is formed between the second cover members 400, and when viewed along the height direction (dh), any one of the first cover members 300 can be located in such a region (A2) between the second cover members 400. Also, when viewed along the height direction (dh), any one of the second cover members 400 can be located in the region (A1, see FIG. 6) between the first cover members 300. Specifically, a region (A1) having a vacant space can be formed between the first cover members 300, and when viewed along the height direction (dh), any one of the second cover members 400 can be located in such a region (A1) between the first cover members 300. In an embodiment of the present invention, when viewed along the height direction (dh), the first cover member 300 and the second cover member 400 can be alternately positioned along the second direction (d2).

[0052] On the other hand, referring to FIG. 2 again, at least one of the first cover member 300 or the second cover member 400 may be plate-shaped with a hollow (CV, Cavity) inside. By realizing at least one of the first cover member 300 or the second cover member 400 in a plate shape having a hollow (CV) instead of a simple plate shape, the rigidity can be supplemented so as to support the battery cell 110. In particular, as described above, the second cover member 400 can be located below the battery cell laminate 120, and such a second cover member 400 can be plate-shaped with a hollow (CV) inside. By realizing the second cover member 400 located below the battery cell laminate 120 in a plate shape having a hollow (CV), the rigidity of the second cover member 400 is increased, and it becomes possible to sufficiently support the battery cell 110, and the stability of the overall structure of the battery module 100 is increased.

[0053] On one hand, a heat sink 600 for cooling the battery cells 110 can be positioned between the battery cell laminate 120 and the second cover member 400. A cooling flow path through which a refrigerant flows can be formed inside such a heat sink 600. The heat generated in the battery cells 110 is transmitted from the respective edge portions of the battery cells 110 to the heat sink 600 and discharged to the outside. That is, the battery module 100 according to the present embodiment has a water-cooled structure and can have an edge cooling structure. There is no particular limitation on the refrigerant flowing inside the heat sink 600, and for example, cooling water can be applied. Also, although not specifically illustrated, a thermal resin layer formed by applying a thermal resin can be positioned between the battery cell laminate 120 and the heat sink 600.

[0054] On the other hand, the battery module 100 according to the present embodiment can further include an end plate 700 that covers both surfaces of the battery cell laminate 120 along the second direction (d2) and the direction opposite thereto. Such an end plate 700 is a plate-shaped member having a certain area and can be connected to the vertical beam 200. One surface of such an end plate 700 can be perpendicular to one surface of the vertical beam 200. That is, in the present embodiment, one surface of the vertical beam 200 is parallel to each of the second direction (d2) and the height direction (dh), and one surface of the end plate 700 can be parallel to each of the first direction (d1) and the height direction (dh). The battery cells 110 can be protected from the outside by being covered by the vertical beam 200 and the end plate 700.

[0055] Hereinafter, a battery pack according to an embodiment of the present invention will be described with reference to FIGS. 9 to 11 and the like.

[0056] FIG. 9 is a perspective view showing a battery pack according to an embodiment of the present invention. FIG. 10 is a side view of the battery pack of FIG. 9 as viewed from the side. FIG. 11 is a cross-sectional view showing a state in which the battery pack according to an embodiment of the present invention is fixed by a long bolt member.

[0057] Referring to FIGS. 9 to 11 together with FIGS. 1, 4 to 8, a battery pack 1000 according to an embodiment of the present invention includes a plurality of battery modules 100, and at least two battery modules 100 are stacked along the height direction (dh). The battery module 100 includes a first battery module 100a and a second battery module 100b that are adjacent to each other along the height direction (dh). Also, a third battery module 100c can be located under the second battery module 100b.

[0058] The second cover member 400a of the first battery module 100a and the first cover member 300b of the second battery module 100b are located in the space between the battery cell stack 120 of the first battery module 100a and the battery cell stack 120 of the second battery module 100b. As described above, when viewed along the height direction (dh), since the first cover member 300 and the second cover member 400 are located in a region where they do not overlap each other, the second cover member 400a of the first battery module 100a and the first cover member 300b of the second battery module 100b are located without overlapping each other, and the height of the structure in which the first battery module 100a and the second battery module 100b are stacked can be reduced.

[0059] Also, in the first battery module 100a, the second cover member 400a can be composed of a plurality, and the second cover members 400a can be arranged at intervals along the second direction (d2). In the second battery module 100b, the first cover member 300b can be composed of a plurality, and the first cover members 300b can be arranged at intervals along the second direction (d2).

[0060] When the first battery module 100a and the second battery module 100b are stacked along the height direction (dh), the second cover member 400a of the first battery module 100a and the first cover member 300b of the second battery module 100b can be alternately positioned along the second direction (d2).

[0061] In the foregoing, the relationship with the first battery module 100a located on the second battery module 100b has been described. However, a similar structure can also be applied to the relationship with the third battery module 100c located below the second battery module 100b. Specifically, the second cover member 400b of the second battery module 100b and the first cover member 300c of the third battery module 100c can be positioned without overlapping each other in the space between the battery cell stack 120 of the second battery module 100b and the battery cell stack 120 of the third battery module 100c. The second cover member 400b of the second battery module 100b and the first cover member 300c of the third battery module 100c can be alternately positioned along the second direction (d2). By designing the first cover members 300, 300b, 300c and the second cover members 400, 400a, 400b so as not to overlap each other, when the plurality of battery modules 100a, 100b, 100c are stacked along the height direction (dh), the height of the entire battery pack 1000 can be reduced. Due to the reduced height, the space utilization of the battery pack 1000 increases, which can lead to an increase in the capacity of the entire battery pack 1000.

[0062] On the other hand, the battery pack 1000 according to the present embodiment may further include a long bolt member 500 that penetrates all of the vertical beams 200a, 200b, 200c of the battery modules 100a, 100b, 100c stacked along the height direction (dh) and is fixed to a vehicle or a pack frame. In FIG. 11, the fastening object 1100 to which the long bolt member 500 penetrating the vertical beams 200a, 200b, 200c is fastened may be a vehicle or a pack frame. The long bolt member 500 can be bolted to a vehicle or a pack frame. For example, after the long bolt member 500 passes through a through hole formed in the fastening object 1100, it can be coupled to a nut member (not shown). As another example, the long bolt member 500 can be directly coupled to a hole having a thread provided in the fastening object 1100.

[0063] During the process of repeated charge and discharge of the battery cell 110, its internal electrolyte may be decomposed, gas may be generated, and the battery cell 110 may swell, that is, a swelling phenomenon may occur. If such swelling of the battery cell 110 cannot be controlled, it may cause structural deformation of the battery module 100 in which a large number of battery cells 110 are stacked, and may also have an adverse effect on the durability and performance of the battery module 100 and the battery pack 1000 including the same.

[0064] In particular, recently, in order to manufacture high-capacity battery modules and battery packs, as battery cells, Pure Si cells and SiO high-content cells are used. In the case of such cells, the degree of swelling is larger. That is, in order to manufacture high-capacity battery modules and battery packs, it is essential to effectively control the swelling of the battery cells 110 inside the battery module and the battery pack. Since the pouch-type battery cell 110 usually has a large degree of swelling in the thickness direction, that is, the first direction (d1) in which the battery cells 110 are stacked, structures directly related to swelling control are the vertical beams 200 arranged on both sides of the battery cell stack 120 and between the battery cells 110.

[0065] The battery module 100 according to this embodiment has a simplified housing structure in which the battery cell stack 120 is partially covered via the vertical beam 200, the first cover member 300, and the second cover member 400, rather than a module housing that encloses the battery cell stack. Thereby, the overall weight and volume of the battery module 100 can be reduced, but it may be difficult to provide side rigidity and durability sufficient to control the swelling of the battery cell 110.

[0066] Therefore, in the battery pack 1000 according to this embodiment, when battery modules 100 with a simplified housing structure are stacked, the vertical beams 200 et al. are fixed to a vehicle or a pack frame using long bolt members 500. As a result, the vertical beams 200, whose rigidity is enhanced by the amount by which the long bolt members 500 are inserted, are designed to control the displacement due to the swelling of the battery cells 110. That is, when the mounting and fixing of the stacked battery modules 100 are performed by the long bolt members 500 passing through the vertical beams 200, at the same time, the vertical beams 200 control the swelling of the battery cells 110 so as to complement the rigidity and durability of the battery module 100 and the battery pack 1000 including the same. In other words, the long bolt member 500 according to this embodiment can perform not only the function of fixing the stacked battery modules 100 but also a function similar to that of so-called reinforcing bars that enhance the rigidity of the vertical beams 200 so as to control the swelling of the battery cells 110.

[0067] In this embodiment, terms indicating directions such as front, rear, left, right, up, and down are used, but such terms are for convenience of explanation and may vary depending on the position of the object to be described and the position of the observer, etc.

[0068] One or more battery modules according to the above-described embodiment can be mounted together with various control and protection systems such as a BMS (Battery Management System), a BDU (Battery Disconnect Unit), and a cooling system to form a battery pack.

[0069] The battery pack can be applied to various devices. Specifically, it can be applied to transportation means such as electric bicycles, electric vehicles, hybrids, and ESSs (Energy Storage Systems), but is not limited thereto, and is applicable to various devices that can use secondary batteries. In particular, the battery pack according to this embodiment can be applied to commercial vehicles.

[0070] As described above, the preferred embodiments of the present invention have been described in detail. However, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

Explanation of Reference Numerals

[0071] 100 Battery module 100a First battery module 100b Second battery module 100c Third battery module 110 Battery cell 120 Battery cell laminate 200 Vertical beam 300 First cover member 400 Second cover member 500 Long bolt member

Claims

1. A battery cell stack in which a plurality of battery cells are stacked along a first direction; At least one vertical beam disposed at least at one location between both side surfaces of the battery cell stack or between the battery cells within the battery cell stack; At least one first cover member located on one side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction; and At least one second cover member located on the other side of the battery cell stack, connected to at least one of the vertical beams, and extending along the first direction; including A battery module located in a region where the first cover member and the second cover member do not overlap each other when viewed along a height direction perpendicular to the first direction.

2. At least one of the first cover members is located on one side of the battery cell stack along the height direction, At least one of the second cover members is located on the other side of the battery cell stack along the height direction, the battery module according to claim 1.

3. At least one of the first cover members and at least one of the second cover members are located on opposite sides of each other with the battery cell stack therebetween, the battery module according to claim 1.

4. At least one of the first cover member or the second cover member is plate-shaped with a hollow inside, the battery module according to claim 1.

5. The second cover member is located at the lower part of the battery cell stack and is plate-shaped with a hollow inside, the battery module according to claim 1.

6. The first cover member and the second cover member are each composed of a plurality, Each of the plurality of first cover members and the plurality of second cover members are spaced apart and arranged along a second direction perpendicular to both the first direction and the height direction, the battery module according to claim 1.

7. When viewed along the height direction, any one of the first cover members is located in a region between the second cover members, the battery module according to claim 6.

8. When viewed along the height direction, any one of the second cover members is located in a region between the first cover members, the battery module according to claim 6.

9. Including a plurality of the battery modules according to claim 1, At least two of the battery modules are stacked along the height direction, The battery module includes a first battery module and a second battery module that are adjacent to each other along the height direction. A battery pack in which the second cover member of the first battery module and the first cover member of the second battery module are located in a space between the battery cell stack of the first battery module and the battery cell stack of the second battery module. **Claim 10** In the battery module, the first cover member and the second cover member are each composed of a plurality. The battery pack according to claim 9, wherein each of the plurality of first cover members and the plurality of second cover members is spaced apart and arranged along a second direction perpendicular to both the first direction and the height direction. **Claim 11** The battery pack according to claim 9, wherein the second cover member of the first battery module and the first cover member of the second battery module are alternately positioned along a second direction perpendicular to both the first direction and the height direction. **Claim 12** The battery pack according to claim 9, further including a long bolt member that penetrates all of the vertical beams of the battery modules stacked along the height direction and is fixed to a vehicle or a pack frame.

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