Battery module and battery pack containing 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 the contents disclosed in the documents of the Korean patent applications are included as part of this specification.

[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, notebook computers, 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 solve air pollution such as 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, free charge and discharge, very low self-discharge rate, and high energy density compared to nickel-based secondary batteries.

[0005] Such lithium secondary batteries primarily use lithium-based oxides and carbon materials as the positive electrode active material and negative electrode active material, respectively. The lithium secondary battery comprises an electrode assembly in which the positive electrode plate and negative electrode plate, each coated with the positive electrode active material and negative electrode active material respectively, are arranged with a separator in between, and a battery case that seals and houses the electrode assembly together with the electrolyte.

[0006] Generally, lithium secondary batteries can be classified into two types based on the shape of their casing: can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of aluminum laminate sheet.

[0007] For secondary batteries used in small devices, two to three battery cells are typically arranged. However, for secondary batteries used in medium to large devices such as automobiles, a battery module is used, which consists of numerous electrically connected battery cells. In such battery modules, the capacity and output are improved by connecting multiple battery cells in series or parallel to each other, forming a stack of battery cells. Furthermore, 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 battery packs installed in passenger cars, battery packs installed in commercial vehicles can be located in the empty space below the cargo area, rather than in the passenger seat. This requires battery packs that are relatively taller.

[0009] When constructing tall battery packs using conventional battery modules, unnecessary space is lost due to factors such as overlapping components between battery modules, assembly tolerances, and space required to allow for swelling. Therefore, there is a need to develop novel battery modules and battery packs with structures that can suppress displacement due to swelling of battery cells within the battery module, while simultaneously minimizing the loss of internal space and increasing energy density. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] The problem that the present invention aims to solve is to provide a battery module and a battery pack including the same that can suppress displacement due to swelling of battery cells within the battery module, minimize lost internal space, and increase energy density.

[0011] However, the problems that the embodiments of the present invention aim to solve are not limited to those described above, and can be broadly expanded within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0012] A battery module according to one 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 positioned on both sides of the battery cell stack or at least one location 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. When viewed along a height direction perpendicular to the first direction, the first cover member and the second cover member are located in regions where they do not overlap each other.

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

[0015] At least one of the first cover member or the second cover member may be in the shape of a plate with a hollow interior.

[0016] The second cover member may be located at the bottom of the battery cell stack and may be in the shape of a plate with a hollow interior.

[0017] The first cover member and the second cover member can each be composed of multiple members. Each of the multiple first cover member and the multiple second cover member can be 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 one embodiment of the present invention includes a plurality of battery modules, at least two of which are stacked along the height direction. The battery modules include a first battery module and a second battery module located 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 the 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 consist of a plurality of members. Each of the plurality of first cover members and the plurality of second cover members may be spaced apart along a second direction perpendicular to both the first direction and the height direction.

[0022] Along a 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 positioned alternately.

[0023] The battery pack may further include long bolt members that penetrate all of the vertical beams of the battery modules stacked along the height direction and are fixed to the vehicle or pack frame. [Effects 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 areas that do not overlap with each other, the total height when the battery modules are stacked along the height direction can be reduced. In other words, space can be reduced and energy density can be increased.

[0025] Furthermore, by fixing the stacked battery modules in the height direction with long bolt members that penetrate the vertical beams of the battery modules, the structural safety of the battery pack can be enhanced, while at the same time effectively suppressing displacement due to swelling of the battery cells inside the battery modules.

[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] [Figure 1] It is a schematic perspective view of a battery module according to an embodiment of the present invention. [Figure 2] It is a cross-sectional view showing a cross-section cut along the cutting line A-A' of FIG. 1. [Figure 3] It is a perspective view showing one of the battery cells included in the battery modules of FIGS. 1 and 2. [Figure 4] It is a perspective view showing a state where the first cover member is removed from the battery module of FIG. 1. [Figure 5] It is a perspective view showing the vertical beam and the second cover member included in the battery module of FIG. 1. [Figure 6] It is a perspective view showing the vertical beam and the first cover member included in the battery module of FIG. 1. [Figure 7] It is a bottom view of the battery module of FIG. 1 seen from below. [Figure 8] It is a plan view of the battery module of FIG. 1 seen from above. [Figure 9] It is a perspective view showing a battery pack according to an embodiment of the present invention. [Figure 10] It is a side view of the battery pack of FIG. 9 seen from the side. [Figure 11] It is a cross-sectional view showing a state where the battery pack according to an embodiment of the present invention is fixed by a long bolt member.

Modes for Carrying Out the Invention

[0028] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings, so that they can be easily implemented by a person with ordinary skill in the art to which the present invention pertains. 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, irrelevant parts have been omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

[0030] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrarily indicated for the sake of explanation, and therefore the present invention is not necessarily limited to those shown. In the drawings, the thicknesses are shown enlarged to clearly represent multiple layers and regions. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for the sake of explanation.

[0031] Furthermore, when a layer, membrane, region, plate, or other part is "on top of" or "on" another part, this includes not only when it is "directly above" the other part, but also when there is another part in between. Conversely, when we say that one part is "directly above" another part, it means that there is no other part in the middle. Also, when we say that something is "on top of" or "on the side of" a reference part, it means that it is located above or below the reference part, and does not necessarily mean that it is located "on top of" or "on the side of" the opposite direction of gravity.

[0032] Furthermore, throughout the specification, when a part "includes" a certain component, unless otherwise stated, it does not mean that other components are excluded, but rather that other components may be included.

[0033] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the cross-section of the subject is viewed from the side after being cut vertically.

[0034] Figure 1 is a schematic perspective view of a battery module according to one embodiment of the present invention. Figure 2 is a cross-sectional view showing a cross-section taken along the cutting line A-A' in Figure 1. Figure 3 is a perspective view showing one of the battery cells included in the battery modules of Figures 1 and 2. Figure 4 is a perspective view showing the battery module of Figure 1 with the first cover member removed.

[0035] Referring to Figures 1 to 4, a battery module 100 according to one 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 positioned on both sides of the battery cell stack 120 or at least one location between the battery cells 110 within 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 in this embodiment may be of various forms, for example, a pouch-type battery cell, a prismatic battery cell, or a cylindrical battery cell. As an example, as shown in Figure 3, the battery cell 110 in this embodiment may be a pouch-type battery cell. The following description will focus on pouch-type battery cells, but the battery cell 110 in this embodiment is not limited to this, and various types of battery cells can be applied. A pouch-type battery cell can be formed by housing an electrode assembly in a pouch case, which is a laminate sheet containing a resin layer and a metal layer, and then bonding the outer periphery of the pouch case. The battery cell 110 may have a rectangular sheet structure. For example, the battery cell 110 in this embodiment may have a structure in which two electrode leads 130 face each other and protrude from one end and the other end, respectively. One of the electrode leads 130 is the positive electrode lead, and the other is the negative electrode lead.

[0037] Referring in particular to Figure 3, the battery cell 110 according to this embodiment has a structure in which two electrode leads 130 face each other and protrude from one end 114a and the other end 114b of the cell body 113, respectively. More specifically, the electrode leads 130 are connected to an electrode assembly (not shown) and protrude 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 bonding both ends 114a, 114b of the cell case 114 and one side 114c connecting them, with the electrode assembly (not shown) housed in the cell case 114. That is, the battery cell 110 according to this embodiment has a total of three sealing parts 114sa, 114sb, and 114sc, and the sealing parts 114sa, 114sb, and 114sc are sealed by methods such as heat fusion, and the remaining one side can be made up of a folding part 115. The cell case 114 can be made of a laminate sheet including a resin layer and a metal layer.

[0039] Although Figure 3 only describes a battery cell 110 in which the electrode leads 130 protrude in both directions, it goes without saying that other embodiments of the present invention also include a pouch-type battery cell in which the electrode leads protrude together in one direction.

[0040] The laminated sheet cell case 114 may include an inner resin layer for sealing, a metal layer to prevent penetration of materials, and an outermost outer resin layer. With respect to the electrode assembly inside the cell case 114, the inner resin layer may be located on the innermost side, the outer resin layer on the outermost side, and the metal layer may be located between the inner and outer resin layers.

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

[0042] The cell case 114 is divided into two parts, and a recessed storage portion can be formed in at least one of the two parts on which an electrode assembly can be placed. Along the outer circumference of such a storage portion, the inner resin layers of the two parts of the cell case 114 are joined to each other, thereby providing sealing portions 114sa, 114sb, and 114sc. The pouch case is sealed in this manner, and the battery cell 110 is manufactured.

[0043] Such battery cells 110 can be composed of multiple cells, and multiple 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 a first direction (d1) while standing upright with one side of each cell body 113 facing each other to form a battery cell stack 120. As a result, one electrode lead 130 of the battery cell 110 can protrude toward a second direction (d2), which will be described later, and the other electrode lead 130 can protrude toward the opposite direction of the second direction (d2).

[0044] The vertical beam 200 is a plate-shaped member having a certain area and can be positioned parallel to one surface of the battery cell 110. The vertical beam 200 can be positioned parallel to one surface of the cell body 113 of the battery cell 110. In other words, one surface of the vertical beam 200 can be perpendicular 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 of the battery cell 110 due to swelling. As described above, the vertical beam 200 is positioned on both sides of the battery cell stack 120 or at least at one location between the battery cells 110 within the battery cell stack 120. As an example, multiple vertical beams 200 may be positioned from the outside of the battery cell stack 120 so as to cover both sides of the battery cell stack 120. Also, the vertical beam 200 can be positioned between the battery cells 110 within the battery cell stack 120. Figures 1 to 4 show a total of four vertical beams 200: two located on both sides of the battery cell stack 120 and two located between the battery cells 110. For structural stability, it is preferable that vertical beams 200 cover both sides of the battery cell stack 120 from the outside. On the other hand, there are no special restrictions on the number of vertical beams 200 located between the battery cells 110 within the battery cell stack 120, and can be determined by considering the number and size of the battery cells 110, etc.

[0045] A vertical beam 200 positioned between the battery cells 110 can divide the battery cell stack 120 into a plurality of sub-battery cell stacks 120a, 120b, and 120c. For example, the battery cell stack 120 may include first to third sub-battery cell stacks 120a, 120b, and 120c, each partitioned by two vertical beams 200. One of the vertical beams 200 may be located between the first sub-battery cell stack 120a and the second sub-battery cell stack 120b, and the other vertical beam 200 may be located between the second sub-battery cell stack 120b and the third sub-battery cell stack 120c.

[0046] Figure 5 is a perspective view showing the vertical beam and second cover member included in the battery module of Figure 1. Figure 6 is a perspective view showing the vertical beam and first cover member included in the battery module of Figure 1. Figure 7 is a bottom view of the battery module of Figure 1, seen from below. Figure 8 is a top view of the battery module of Figure 1, seen from above.

[0047] Referring to Figures 1, 2, and 5-8, in the battery module 100 according to this 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] In this embodiment, each of the first cover member 300 and the second cover member 400 is connected to the vertical beam 200 and extends along a 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 the battery cell stack 120. As an example, as shown in Figures 1, 2, 5, and 6, the first cover member 300 can be located on the upper part of the battery cell stack 120, and the second cover member 400 can be located on the lower part of the battery cell stack 120. In another embodiment of the present invention, the first cover member may be located at the bottom of the battery cell stack 120, and the second cover member may be located at the top of the battery cell stack 120.

[0049] When viewed along the height direction (dh), the first cover member 300 and the second cover member 400 are located in areas where they do not overlap with each other. Therefore, when multiple battery modules 100 are stacked along the height direction (dh), the second cover member 400 of the upper battery module 100 and the first cover member 300 of the lower battery module 100 can be located in areas where they do not overlap with each other. In other embodiments, where the first cover member is located at the bottom of the battery cell stack 120 and the second cover member is located at the top of the battery cell stack 120, the first cover member of the upper battery module 100 and the second cover member of the lower battery module 100 can be located without overlapping with each other. In this embodiment, the first cover member 300 and the second cover member 400 are set so as not to overlap with each other, which reduces the total height when the battery modules 100 are stacked along the height direction (dh). 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 composed of multiple members. Each of the multiple first cover members 300 and the multiple second cover members 400 may be spaced apart along a second direction (d2) that is 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 designated for the sake of explanation and are all perpendicular to each other. As an example, an embodiment 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 is located spaced apart along the second direction (d2) is shown in Figures 1, 5 to 8.

[0051] Furthermore, when viewed along the height direction (dh), any one of the first cover members 300 can be located in the region between the second cover members 400 (A2, see Figure 5). Specifically, a region (A2) with an empty 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. Furthermore, when viewed along the height direction (dh), any one of the second cover members 400 can be located in the region between the first cover members 300 (A1, see Figure 6). Specifically, a region (A1) with an empty space is 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 one 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 positioned alternately along the second direction (d2).

[0052] On the other hand, referring again to Figure 2, at least one of the first cover member 300 or the second cover member 400 may be a plate shape having a cavity (CV) inside. By realizing at least one of the first cover member 300 or the second cover member 400 as a plate shape having a cavity (CV) rather than a simple plate shape, the rigidity can be supplemented so that it can support the battery cell 110. In particular, as described above, the second cover member 400 can be located at the bottom of the battery cell stack 120, and such a second cover member 400 may be a plate shape having a cavity (CV) inside. By realizing the second cover member 400 located at the bottom of the battery cell stack 120 as a plate shape having a cavity (CV), the rigidity of the second cover member 400 is increased, so that it can adequately support the battery cell 110, and the overall structural stability of the battery module 100 is increased.

[0053] On the other hand, a heat sink 600 for cooling the battery cells 110 can be positioned between the battery cell stack 120 and the second cover member 400. A cooling channel through which a coolant flows can be formed inside such a heat sink 600. The heat generated in the battery cells 110 is transferred from each edge portion of the battery cells 110 to the heat sink 600 and discharged to the outside. In other words, the battery module 100 according to this embodiment has a water-cooled structure and can have an edge cooling structure. There are no special restrictions on the coolant flowing inside the heat sink 600, and cooling water can be used as an example. Although not specifically shown in the figures, a thermal resin layer formed by coating thermal resin can be positioned between the battery cell stack 120 and the heat sink 600.

[0054] On the other hand, the battery module 100 according to this embodiment may further include an end plate 700 that covers both sides of the battery cell stack 120 along the second direction (d2) and the opposite direction. 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 may be perpendicular to one surface of the vertical beam 200. That is, in this embodiment, one surface of the vertical beam 200 may be parallel to the second direction (d2) and the height direction (dh), and one surface of the end plate 700 may be parallel to 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] A battery pack according to one embodiment of the present invention will be described below with reference to Figures 9 to 11 and other figures.

[0056] Figure 9 is a perspective view showing a battery pack according to one embodiment of the present invention. Figure 10 is a side view of the battery pack of Figure 9. Figure 11 is a cross-sectional view showing how the battery pack according to one embodiment of the present invention is fixed by a long bolt member.

[0057] Referring to Figures 9 to 11 in conjunction with Figures 1 and 4 to 8, a battery pack 1000 according to one embodiment of the present invention includes a plurality of battery modules 100, and at least two of the 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 located adjacent to each other along the height direction (dh). A third battery module 100c may be located below 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), the first cover member 300 and the second cover member 400 are located in regions where they do not overlap with each other, so 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 with each other, and the height of the stacked structure of the first battery module 100a and the second battery module 100b can be reduced.

[0059] Furthermore, in the first battery module 100a, the second cover member 400a can be composed of multiple members, and the second cover members 400a can be arranged spaced apart along the second direction (d2). In the second battery module 100b, the first cover member 300b can be composed of multiple members, and the first cover members 300b can be arranged spaced apart 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 positioned alternately along the second direction (d2).

[0061] The above describes the relationship between the second battery module 100a, which is located on the second battery module 100b, but a similar structure can be applied to the relationship between the second battery module 100b and the third battery module 100c, which is 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 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 without overlapping each other. 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 alternately along the second direction (d2). By designing the first cover members 300, 300b, and 300c and the second cover members 400, 400a, and 400b in this manner so that they do not overlap each other, the overall height of the battery pack 1000 can be reduced when multiple battery modules 100a, 100b, and 100c are stacked along the height direction (dh). The reduced height increases the usable space of the battery pack 1000, which can lead to an increase in the overall capacity of the battery pack 1000.

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

[0063] During repeated charging and discharging cycles, the internal electrolyte of the battery cell 110 can decompose, generating gas and potentially causing the battery cell 110 to swell, a phenomenon known as swelling. If this swelling of the battery cell 110 cannot be controlled, it may cause structural deformation of the battery module 100, which consists of many stacked battery cells 110, and may also adversely affect the durability and performance of the battery module 100 and the battery pack 1000 containing it.

[0064] In particular, recently, to manufacture high-capacity battery modules and battery packs, pure Si cells and SiO high-content cells are used as battery cells, but in the case of these cells, the degree of swelling is greater. In other words, 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 or battery pack. Pouch-type battery cells 110 usually have a large degree of swelling in the thickness direction, i.e., the first direction (d1) in which the battery cells 110 are stacked. Therefore, the structures directly related to swelling control are the vertical beams 200 placed on both sides of the battery cell stack 120 and between the battery cells 110.

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

[0066] Therefore, in this embodiment, the battery pack 1000, in which battery modules 100 with a simplified housing structure are stacked, uses long bolt members 500 to fix the vertical beams 200 to the vehicle and pack frame. As a result, the vertical beams 200, whose rigidity is strengthened by the insertion of the long bolt members 500, are designed to control the displacement of the battery cells 110 due to swelling. That is, when the stacked battery modules 100 are mounted and fixed by the long bolt members 500 that penetrate the vertical beams 200, the vertical beams 200 can simultaneously control the swelling of the battery cells 110, thereby complementing the rigidity and durability of the battery modules 100 and the battery pack 1000 including them. In other words, the long bolt members 500 in this embodiment not only have the function of fixing the stacked battery modules 100, but can also play a function similar to reinforcing bars, strengthening the rigidity of the vertical beams 200 to control the swelling of the battery cells 110.

[0067] In this embodiment, terms indicating direction such as front, back, left, right, up, and down were used. However, these terms are for illustrative purposes only and may differ depending on the position of the object in question, the observer's position, 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 aforementioned battery pack can be applied to a variety of devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, as well as to ESS (Energy Storage Systems), but is not limited to these, and can be applied to a wide range of devices that can use secondary batteries. In particular, the battery pack according to this embodiment can be applied to commercial vehicles.

[0070] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art that utilize the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention. [Explanation of Symbols]

[0071] 100 Battery Modules 100a First Battery Module 100b Second Battery Module 100c Third Battery Module 110 battery cells 120 Battery Cell Stack 200 Vertical beam 300 First cover member 400 Second cover member 500 Long bolt component

Claims

1. A battery cell stack in which multiple battery cells are stacked along a first direction; At least one vertical beam positioned at at least one location on either side 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 Includes 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 the 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. The first cover member and the second cover member are each composed of multiple members. A battery module in which, when viewed along a height direction perpendicular to the first direction, the first cover member and the second cover member are alternately positioned along a second direction perpendicular to both the first direction and the height direction.

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

3. The battery module according to claim 1, wherein at least one of the first cover members and at least one of the second cover members are located on opposite sides of the battery cell stack.

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

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

6. The battery module according to claim 1, wherein each of the plurality of first cover members and the plurality of second cover members is spaced apart along a second direction perpendicular to both the first direction and the height direction.

7. A plurality of battery modules as described in 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 located 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 the space between the battery cell stack of the first battery module and the battery cell stack of the second battery module.

8. In the aforementioned battery module, the first cover member and the second cover member are each composed of multiple members. The battery pack according to claim 7, wherein each of the plurality of first cover members and the plurality of second cover members is spaced apart along a second direction perpendicular to both the first direction and the height direction.

9. A battery module, A battery cell stack in which multiple battery cells are stacked along a first direction; At least one vertical beam positioned at at least one location on either side 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 Includes 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; The device includes multiple battery modules, such that when viewed along the 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. 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 located 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 the space between the battery cell stack of the first battery module and the battery cell stack of the second battery module. 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 alternately positioned along a second direction perpendicular to both the first direction and the height direction.

10. The battery pack according to claim 7, further comprising 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 pack frame.

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