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 battery cells are stacked along a first direction; and at least one bus bar located on one or both sides of the battery cell stack. An electrode lead protrudes from the battery cell along a second direction perpendicular to the first direction. The bus bar includes a first portion and a second portion extending from the first portion and forming a certain angle with one surface of the first portion, and the electrode lead is joined to the second portion.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0167843 filed on December 5, 2022, and all the contents disclosed in the document of the Korean patent application 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 having a novel connection form between an electrode lead and a bus bar 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 technological development in fields related to such mobile devices has been 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 measure to solve problems such as air pollution in conventional gasoline vehicles that use fossil fuels, and the need for the development of secondary batteries is increasing.

[0004]

[0005] Generally, lithium secondary batteries can be classified into can - type secondary batteries in which an electrode assembly is built into a metal can according to the shape of the exterior material, and pouch - type secondary batteries in which an electrode assembly is built into a pouch of an aluminum laminate sheet.In the case of secondary batteries used in small devices, two to three battery cells are arranged, but in the case of secondary batteries used in medium to large devices such as automobiles, a battery module is used in which many battery cells are electrically connected. In such battery modules, the capacity and output are improved by connecting many battery cells in series or parallel to each other to form 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.

[0006] Conventional battery modules can utilize busbars and busbar frames for electrical connections between multiple battery cells. The structure of busbars and busbar frames used in conventional battery modules will be described below with reference to Figures 1 and 2.

[0007] Figure 1 is a perspective view showing a conventional battery module. Figure 2 is a magnified view of section "A" in Figure 1. In particular, Figure 1 shows the battery module standing upright to illustrate the busbar frame and busbar configuration.

[0008] Referring to Figures 1 and 2, a conventional battery module 10 includes a battery cell stack 12 in which multiple battery cells 11 are stacked, and busbar frames 30 positioned on both sides of the battery cell stack 12. Busbars 40 can be mounted on such busbar frames 30.

[0009] The busbar 40 is for electrical connection between multiple battery cells 11, and the electrode leads 11L of the battery cells 11 can pass through slits formed in the busbar frame 30 and then bend to connect with the busbar 40. In some cases, the electrode leads 11L can also pass through slits 40S formed in the busbar 40.

[0010] In the connection between the electrode lead 11L and the busbar 40, there are no restrictions on the method of connection as long as an electrical connection is possible; for example, it can be connected by welding. The battery cells 11 can be electrically connected in series or parallel via the busbar 40.

[0011] The aforementioned connection configuration of the battery cells 11 may be susceptible to damage due to tensile force. This will be explained with reference to Figure 3.

[0012] Figure 3 is a cross-sectional view illustrating damage to an electrode tab or damage to the connection between an electrode tab and an electrode lead in a conventional battery module.

[0013] Referring to Figure 3, the battery cell 11 can be manufactured by housing an electrode assembly 11A inside a pouch-type cell case 11C, and then sealing the outer periphery of the cell case 11C to form a sealing portion 11S. The electrode assembly 11A may include electrodes and a separator membrane placed between the electrodes. Each electrode includes an electrode tab 11t, which can be connected to an electrode lead 11L by welding or other means.

[0014] The electrode lead 11L protrudes from the outside of the cell case 11C and, as described above, passes through the slit 30S of the busbar frame 30 and the slit 40S of the busbar 40, then bends and can be connected to the busbar 40.

[0015] At this time, the electrode lead 11L is welded to the surface of the busbar 40 with the electrode lead 11L in close contact. Figure 3 shows only one electrode lead 11L protruding from one battery cell 11 being joined to the busbar 40, but there are also cases where multiple electrode leads 11L protruding from multiple battery cells 11 are joined to a single busbar 40. In order to make the electrode lead 11L in close contact with the surface of the busbar 40, the electrode lead 11L is bent to form a bending portion 11LB. Furthermore, in order to make multiple electrode leads 11L in close contact with the surface of the busbar 40, the length of the electrode lead 11L must be different for each battery cell 11. Therefore, in conventional battery modules 10, the process of cutting the electrode lead (llL) and the process of bending the electrode lead 11L are essential.

[0016] Furthermore, tensile force (TF) is generated in the electrode lead 11L during the bending process. This tensile force (TF) can cause stress to concentrate in the electrode tab 11t and the connection between the electrode tab 11t and the electrode lead 11L. In severe cases, this can lead to problems such as the electrode tab 11t itself breaking or the connection between the electrode tab 11t and the electrode lead 11L breaking. This is a serious problem that can even lead to the risk of fire due to internal short circuits, so it is necessary to develop technology that can prevent the breakage of the electrode tab or the connection between the electrode tab and the electrode lead. [Overview of the Initiative] [Problems that the invention aims to solve]

[0017] The problem that the present invention aims to solve is to provide a battery module having a novel connection configuration between an electrode lead and a busbar, and a battery pack including the same, so as to prevent damage to the electrode tab itself and damage to the connection portion between the electrode tab and the electrode lead.

[0018] 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]

[0019] A battery module according to an embodiment of the present invention includes a battery cell stack in which battery cells are stacked along a first direction, and at least one bus bar located on one or both sides of the battery cell stack. An electrode lead protrudes from the battery cell along a second direction perpendicular to the first direction. The bus bar includes a first portion and a second portion that forms a certain angle with one surface of the first portion and extends from the first portion, and the electrode lead is joined to the second portion.

[0020] The battery cell may be a pouch-type battery cell, and in the battery cell stack, the battery cells can be stacked in a standing state such that one surface of each battery cell faces the other.

[0021] The second portion can extend such that one surface of the second portion is perpendicular to one surface of the first portion.

[0022] One surface of the first portion is parallel to the first direction, and one surface of the second portion can be parallel to the second direction.

[0023] The electrode lead can be welded and joined to the second portion.

[0024] An opening portion can be formed in the bus bar, and at least one of the electrode leads can pass through the opening portion and be joined to the second portion.

[0025] The battery module can further include a bus bar frame located between the battery cell stack and the bus bar, to which the bus bar is attached. A slit is formed in the bus bar frame, and the electrode lead can pass through the slit and be joined to the second portion of the bus bar.

[0026] A bead portion that protrudes in a direction different from the second direction can be formed on the electrode lead.

[0027] The bead portion can protrude from an intermediate portion of the electrode lead in a direction parallel to the first direction.

[0028] The bead portion may be a portion formed by bending the electrode lead at least three times.

[0029] A joint portion, which is a portion where the electrode lead and the second portion are joined, can be provided at a portion where the bead portion is connected to the electrode lead.

[0030] A laser can be irradiated onto a portion where the bead portion is connected to the electrode lead to form the joint portion.

[0031] The battery module can further include a module frame in which the battery cell laminate is housed.

[0032] A battery pack according to an embodiment of the present invention includes the battery module.

Advantages of the Invention

[0033] According to an embodiment of the present invention, by designing the bus bar to include a first portion and a second portion, the electrode lead can be joined to the bus bar without bending the electrode lead. As a result, since no bending portion is formed on the electrode lead, the tensile force due to bending does not act on the electrode lead, and breakage of the electrode tab or breakage of the connection portion between the electrode tab and the electrode lead can be prevented.

[0034] Since no bending portion is formed on the electrode lead, the process of bending the electrode lead is unnecessary. In addition, since each battery cell can be positioned at a constant distance from the joint portion between the electrode lead and the bus bar, the process of cutting the electrode lead is also unnecessary.

[0035] Furthermore, according to embodiments of the present invention, a bead portion can be formed that protrudes from the electrode lead. Even if a bending portion is not formed on the electrode lead, the bead portion enables stable bonding between the electrode lead and the busbar.

[0036] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawing]

[0037] [Figure 1] This is a perspective view showing a conventional battery module. [Figure 2] This is a magnified view of section "A" in Figure 1. [Figure 3] This is a cross-sectional view illustrating damage to an electrode tab or damage to the connection between an electrode tab and an electrode lead in a conventional battery module. [Figure 4] This is an exploded perspective view showing a battery module according to one embodiment of the invention. [Figure 5] This is a plan view showing one of the battery cells included in the battery module in Figure 4. [Figure 6] This is a partial drawing showing the battery cell stack and busbars included in the battery module shown in Figure 4. [Figure 7] This is a magnified view of the junction between the electrode leads and busbars of the battery cell shown in Figure 6. [Figure 8] This is a cross-sectional view showing a section cut along the cutting line B-B' in Figure 6. [Figure 9] This is a perspective view showing a busbar according to one embodiment of the present invention. [Figure 10] This is a drawing showing the electrode leads of a battery cell according to one embodiment of the present invention. [Figure 11] This is a drawing showing the electrode leads of a battery cell according to one embodiment of the present invention. [Figure 12] This diagram shows the process of joining an electrode lead and a busbar according to one embodiment of the present invention. [Figure 13] This diagram shows the process of joining an electrode lead and a busbar according to one embodiment of the present invention. [Figure 14] This is a drawing showing the electrode leads of a battery cell according to another embodiment of the present invention. [Figure 15] This is a perspective view showing a busbar frame according to one embodiment of the present invention. [Modes for carrying out the invention]

[0038] 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.

[0039] 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.

[0040] 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.

[0041] Furthermore, when a layer, membrane, region, plate, or other part is "on top of" or "on top of" 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 top 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 top of" the opposite direction of gravity.

[0042] Furthermore, throughout the specification, when a part "includes" a certain component, unless otherwise stated, it means that it may include other components rather than excluding them.

[0043] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the subject is viewed from the side of a cross-section cut perpendicularly into it.

[0044] Figure 4 is an exploded perspective view showing a battery module according to one embodiment of the present invention. Figure 5 is a plan view showing one of the battery cells included in the battery module of Figure 4. Figure 6 is a partial drawing showing the battery cell stack and busbar included in the battery module of Figure 4.

[0045] Referring to Figures 4 to 6, a battery module 100 according to one embodiment of the present invention includes a battery cell stack 120 in which battery cells 110 are stacked along a first direction (d1), and at least one bus bar 500 located on one or both sides of the battery cell stack 120.

[0046] The busbar 500 preferably includes a metal material as an intermediary for the electrical connection between the electrode leads 111 of the battery cell 110. Whether the busbar 500 is located on one side or both sides of the battery cell stack 120 is determined by whether the electrode leads 111 of the battery cell 110 protrude in only one direction or in both directions. The battery cell 110 according to this embodiment will be described in detail below.

[0047] The battery cell 110 is a pouch-type battery cell and can have a rectangular sheet shape. The battery cell 110 can be formed by housing an electrode assembly in a laminate sheet pouch case containing a resin layer and a metal layer, and then bonding the outer periphery of the pouch case. Specifically, the battery cell 110 can have a structure in which two electrode leads 111 face each other and protrude from one end 114a and the other end 114b of the battery body 113, respectively. In another embodiment, the battery cell 110 can have a structure in which all electrode leads 111 protrude in one direction. One of the electrode leads 111 is the positive electrode lead and the other is the negative electrode lead.

[0048] The battery cell 110 can be manufactured by bonding both ends 114a, 114b of the pouch case 114 and one side 114c connecting them, with the electrode assembly (not shown) housed in the pouch case 114. In other words, the battery cell 110 according to one embodiment of the present invention has a total of three sealing parts, and the sealing parts are sealed by methods such as fusion bonding, and the remaining other side can be made up of a folding part 115. In other words, the battery cell 110 according to this embodiment may be a pouch-type battery cell in which the electrode assembly is housed inside the pouch case 114 and the outer periphery of the pouch case 114 is sealed.

[0049] Such battery cells 110 are stacked along a first direction (d1) to form a battery cell stack 120. Specifically, in the battery cell stack 120, the battery cells 110 can be stacked along the first direction (d1) while standing upright with one face of each battery cell 110 facing the other.

[0050] At this time, the electrode leads 111 protrude from the battery cell along a second direction (d2) perpendicular to the first direction (d1). This allows the busbar 500 to also be positioned on one side of the second direction (d2) with respect to the battery cell stack 120.

[0051] In this specification, the first direction (d1) is shown as the y-axis direction, and the second direction (d2) is shown as the x-axis direction.

[0052] On the other hand, if the electrode leads 111 of the battery cell 110 protrude in both directions from the battery cell 110, then another electrode lead 111 can protrude in the opposite direction to the second direction (d2), that is, in the -x axis direction. This allows the other busbars 500 to also be positioned on one side of the battery cell stack 120 that is opposite to the second direction (d2).

[0053] The following describes in detail the busbar configuration and the connection between the busbar and the electrode lead in this embodiment.

[0054] Figure 7 is a magnified partial drawing showing the junction between the electrode leads and busbar of the battery cell in Figure 6. Figure 8 is a cross-sectional view showing a cross-section cut along the cutting line B-B' in Figure 6. Figure 9 is a perspective view showing a busbar according to one embodiment of the present invention.

[0055] Referring to Figures 6 to 9, the busbar 500 in this embodiment includes a first portion 510 and a second portion 520 extending from the first portion 510 at a certain angle to one surface of the first portion 510, and the electrode leads 111 of the battery cell 110 are joined to the second portion 520. As described above, the busbar 500 is a member that is joined to the electrode leads 111 of the battery cell 110 as an intermediary for electrical connection between the battery cells 110.

[0056] For example, the second portion 520 can extend at an angle of 45 to 135 degrees with respect to one surface of the first portion 510. More specifically, the second portion 520 can extend such that one surface of the second portion 520 is perpendicular to one surface of the first portion 510. In particular, one surface of the first portion 510 may be parallel to the first direction (d1), and one surface of the second portion 520 may be parallel to the second direction (d2). That is, one surface of the first portion 510 can be parallel to the direction in which the battery cells 110 are stacked, and the second portion 520 can be parallel to the direction in which the electrode leads 111 protrude from the battery cells 110.

[0057] In this embodiment, the busbar 500 further includes not only a first portion 510 but also a second portion 520 that forms a certain angle with the first portion 510, and the electrode lead 111 is joined to such a second portion 520.

[0058] If a busbar consisting only of the first part is to be made, it will have a structure similar to the conventional busbar 40 described in Figures 1 to 3. As described above, when joining the electrode lead 11L to the busbar 40, the electrode lead 11L was bent to form a bending portion 11LB in order to make the electrode lead 11L tightly adhere to the surface of the busbar 40. As a result, the processes of cutting the electrode lead 11L and bending the electrode lead 11L were required, and damage to the electrode lead 11L occurred due to the tensile force (TF) generated during the bending process of the electrode lead 11L.

[0059] On the other hand, in the case of the busbar 500 according to this embodiment, a second portion 520 is additionally provided, and the electrode lead 111 is joined to this second portion 520. Therefore, there is no need to bend the electrode lead 111 during the process of joining it to the busbar 500. Since no tensile force due to bending acts on the electrode lead 111, damage to the electrode tab or damage to the connection portion between the electrode tab and the electrode lead can be prevented.

[0060] Furthermore, since the process of bending the electrode leads is unnecessary, and each battery cell 110 can be positioned consistently from the junction between the electrode lead 111 and the busbar 500, the process of cutting the electrode lead 111 is also unnecessary. In other words, some processes can be omitted, reducing product production costs and improving productivity.

[0061] On the other hand, as long as electrical connection between the electrode lead 111 and the second part 520 is possible, there are no particular restrictions on the method of joining the electrode lead 111 and the second part 520. For example, the electrode lead 111 can be welded to the second part 520. In other words, a joint can be formed on the electrode lead 111 by welding. Welding and joints will be explained again below with reference to Figures 10 to 13.

[0062] In this embodiment, the busbar 500 has an opening 500P, and at least one of the electrode leads 111 can pass through the opening 500P and be joined to the second portion 520. In particular, the opening 500P can be formed in the first portion 510 of the busbar 500. A single busbar 500 is provided with multiple second portions 520, and the opening 500P can be provided to join the electrode leads 111 to a second portion 520 located towards the center rather than the outermost one. In addition, other electrode leads 111 can be joined to the second portion 520 without passing through the opening 500P, as shown in the figure. In particular, some electrode leads 111 can be joined to the outermost second portion 520 without passing through the opening 500P.

[0063] As described above, by providing multiple second portions 520 on a single bus bar 500, each battery cell 110 can be positioned at a constant distance from the junction between the electrode lead 111 and the bus bar 500. This eliminates the need for the process of cutting the electrode lead, unlike in the conventional method. The open portion 500P is a portion provided for the convenience of joining some of the electrode leads 111 and the second portions 520 when multiple second portions 520 are formed on a single bus bar 500.

[0064] The electrode lead and the bead portion formed thereon according to this embodiment will be described in detail below with reference to Figures 10 and 11, etc.

[0065] Figures 10 and 11 are diagrams showing the electrode leads of a battery cell according to one embodiment of the present invention. Specifically, Figure 10 is a partial perspective view of the electrode leads according to this embodiment. Figure 11 is a plan view showing the electrode leads according to this embodiment as seen along the -z axis direction on the xy plane.

[0066] Referring to Figures 10 and 11 in conjunction with Figures 7 and 8, the electrode lead 111 in this embodiment does not need to be bent perpendicular to the direction of protrusion from the battery cell 110, as explained earlier, because it is joined to the second portion 520.

[0067] However, in this embodiment, the electrode lead 111 can have a bead portion 111B that protrudes in a direction different from the second direction (d2). In other words, although the electrode lead 111 protrudes from the battery cell 110 along the second direction (d2), it is not simply formed in a plate shape, but rather a bead portion 111B can be formed in the middle of the electrode lead 111 that protrudes in a direction different from the second direction (d2). More specifically, the bead portion 111B can protrude from the middle portion of the electrode lead 111 in a direction parallel to the first direction (d1).

[0068] The welding of the electrode lead 111 and the function of the bead portion 111B according to this embodiment will be described below with reference to Figures 12 and 13.

[0069] Figures 12 and 13 are diagrams illustrating the process of joining an electrode lead and a busbar according to one embodiment of the present invention.

[0070] Referring to Figures 12 and 13 in conjunction with Figures 8, 10, and 11, as mentioned above, the electrode lead 111 can be welded to the second portion 520. Since the second portion 520 is provided on the busbar 500, it is not necessary to bend the electrode lead 111, but the welding process may be more difficult compared to conventional electrode leads 11L which have a curved shape. As shown in Figure 3, in the conventional case, since the electrode lead 11L is curved, the portion where the electrode lead 11L and the busbar 40 are in close contact is visible from the front, and welding is performed by irradiating this portion with a laser or the like, so the welding process is relatively simple. On the other hand, in the electrode lead 111 according to this embodiment, since there is no portion that is bent at a right angle, the portion where the electrode lead 111 and the second portion 520 are in close contact is not a surface that is visible from the front, and it may be difficult to irradiate it with a laser at an angle.

[0071] In order to improve weldability and achieve a stable welded joint between the electrode lead 111 and the second portion 520, the bead portion 111B described above is formed on the electrode lead 111 in this embodiment.

[0072] As shown in Figures 12 and 13, the joint portion 111A, which is the portion where the electrode lead 111 and the second portion 520 are joined, can be provided in the portion where the bead portion 111B is connected to the electrode lead 111. Here, the portion where the bead portion 111B is connected to the electrode lead 111 means the starting portion where the bead portion 111B begins to protrude from the electrode lead 111. In other words, the portion where the bead portion 111B is connected to the electrode lead 111 can be joined to the second portion 520 to form the joint portion 111A.

[0073] More specifically, a laser (L) is irradiated onto the portion of the bead section 111B that is connected to the electrode lead 111, thereby forming a joint 111A. The laser (L) is irradiated at an angle of approximately 45 degrees to one surface of the second section 520 to form the joint 111A, thereby electrically connecting the electrode lead 111 and the busbar 500. As mentioned above, the portion where the electrode lead 111 and the second section 520 are in close contact is not a surface visible from the front, but since the bead section 111B is provided and a laser (L) tilted at a certain angle is irradiated onto the portion of the bead section 111B that is connected to the electrode lead 111, a stable welding process is possible. In other words, the bead section 111B according to this embodiment can be provided to improve the processability of welding so that the electrode lead 111 protruding along the second direction (d2) is stably welded to the second section 520.

[0074] Figure 14 is a diagram showing the electrode leads of a battery cell according to another embodiment of the present invention.

[0075] Referring to Figure 14, the electrode lead 111 according to another embodiment of the present invention may have a bead portion 111B'. The bead portion 111B' can protrude from the intermediate portion of the electrode lead 111 in a direction different from the second direction (d2), for example, in a direction parallel to the first direction (d1). This is the same as the bead portion 111B described earlier. In this embodiment, the bead portion 111B' can be formed by attaching a plate-shaped member to the intermediate portion of the electrode lead 111.

[0076] On the other hand, referring again to Figures 10 and 11, the bead portion 111B according to one embodiment of the present invention may be a portion formed by bending the electrode lead 111 at least three times. Figure 11 shows the electrode lead 111 with three bending portions (BP) formed, ultimately resulting in the formation of the bead portion 111B. Unlike the bead portion 111B' to which a plate-shaped member is attached, the bead portion 111B according to this embodiment can be formed simply by bending the electrode lead 111 multiple times, thus having the advantage of a simple manufacturing method. In other words, the bead portions 111B and 111B' in the present invention are not particularly limited in shape as long as they protrude from the electrode lead 111 in a direction different from the second direction (d2), but considering the convenience of the manufacturing method, the bead portion 111B formed by bending the electrode lead 111 at least three times is preferred.

[0077] Figure 15 is a perspective view showing a busbar frame according to one embodiment of the present invention.

[0078] Referring to both Figure 6 and Figure 15, the battery module according to this embodiment may further include a busbar frame 600. Although only the busbar 500 is shown in Figure 6 for ease of explanation, the busbar frame 600 may be located between the battery cell stack 120 and the busbar 500. The busbar 500 can be mounted on such a busbar frame 600.

[0079] Specifically, the busbar 500 can be mounted on one side of the busbar frame 600, and the battery cell stack 120 can be positioned on the other side of the busbar frame 600. The electrode leads 111 of the battery cell 110 can pass through the slit 600S formed in the busbar frame 600 and be joined to the busbar 500. The joining of the electrode leads 111 to the busbar 500 has been explained earlier, so it will be omitted here.

[0080] The busbar frame 600 may include an electrically insulating material. For example, the busbar frame 600 may include an electrically insulating plastic material. The busbar frame 600 is a component positioned to prevent short circuits from occurring when parts of the battery cell 110 other than the electrode leads 111 come into contact with the busbar 500.

[0081] Although not shown in the diagram, the busbar frame 600 can be fitted with terminal busbars that function as external input / output terminals, and a sensing assembly that transmits temperature and voltage information of the battery cells.

[0082] On the other hand, referring again to Figure 4, the battery module 100 according to this embodiment may further include a module frame 200 in which a battery cell stack 120 is housed. The module frame 200 is a component that houses the battery cell stack 120 inside and may include two side portions 210, 220, an upper portion 230, and a lower portion 240. The module frame 200 may also be in a configuration in which both sides corresponding to the second direction and the opposite direction are open. The battery cell stack 120 can be housed through either of the open sides. The module frame 200 may include a metal material having a predetermined strength to protect internal electrical components.

[0083] The module frame 200 shown in Figure 4 may be a monoframe in which two side sections 210, 220, an upper section 230, and a lower section 240 are integrated. That is, it may be manufactured by extrusion molding and have two side sections 210, 220, an upper section 230, and a lower section 240 integrated. Although not specifically shown, as another embodiment of the present invention, a module frame in which a U-shaped frame and an upper plate are welded to each other is also possible. Looking at the stacking direction of the module frame 200 and the battery cells 110, the battery cells 110 can be stacked from one side section 210 to the other side section 220 such that one surface of the battery cell 110 is parallel to one surface of the side sections 210, 220 of the module frame 200.

[0084] On the other hand, the battery module 100 according to this embodiment may further include end plates 300 located on the open sides of the module frame 200. The end plates 300 may be positioned to cover the battery cell stack 120 on the open sides of the module frame 200. The corners of each end plate 300 may be joined to the corresponding corners of the module frame 200 by welding. The end plates 300 may include a metal material having a predetermined strength and can protect the battery cell stack 120 and other electrical components from external impacts. The busbars 500 and busbar frames 600 described earlier may be positioned between the end plates 300 and the battery cell stack 120.

[0085] The battery module 100 may further include a thermal resin layer 400 located between the battery cell stack 120 and the lower surface portion 240 of the module frame 200. One side of the battery cell 110 can be bonded to the thermal resin layer 400. Specifically, the thermal resin layer 400 can be formed by curing after the thermal resin is injected or applied. The thermal resin may contain a thermally conductive adhesive, specifically at least one of silicon, urethane, or acrylic materials. The thermal resin is liquid when applied but hardens after application to bond to one side of the battery cell 110. As a result, the thermal resin layer 400 can serve to fix the battery cell 110. Furthermore, the thermal resin layer 400 has excellent thermal conductivity and can quickly transfer the heat generated in the battery cell 110 to the underside of the battery module.

[0086] In this embodiment, terms indicating directions such as front, back, left, right, up, and down were used. However, these terms are for explanatory convenience and may vary depending on the position of the object in question, the observer's position, etc.

[0087] 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.

[0088] The aforementioned battery modules and battery packs can be applied to a variety of devices. Specifically, they can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, as well as to ESS (Energy Storage Systems), but are not limited to these; they can be applied to a variety of devices that can use secondary batteries.

[0089] 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]

[0090] 100 Battery Modules 110 battery cells 111 Electrode Leads 111A Joint 111B Bead section 120 Battery Cell Stack 200 Module Frames 300 End Plate 400 Thermal resin layer 500 Bus Bar 510 Part 1 520 Part 2 600 Busbar Frame

Claims

1. A battery cell stack in which battery cells are stacked along a first direction, and At least one busbar located on one or both sides of the battery cell stack Includes, The electrode leads protrude from the battery cell along a second direction perpendicular to the first direction, The busbar includes a first portion and a second portion that extends from the first portion at a certain angle to one surface of the first portion. The electrode lead is joined to the second portion, A battery module in which a bead portion is formed on the electrode lead, protruding perpendicular to the second portion and in a direction different from the second direction.

2. The aforementioned battery cell is a pouch-type battery cell, The battery module according to claim 1, wherein in the battery cell stack, the battery cells are stacked in an upright position with one side of each battery cell facing the other.

3. The battery module according to claim 1, wherein the second portion extends such that one surface of the second portion is perpendicular to one surface of the first portion.

4. The battery module according to claim 1, wherein one surface of the first portion is parallel to the first direction, and one surface of the second portion is parallel to the second direction.

5. The battery module according to claim 1, wherein the electrode lead is welded to the second portion.

6. An opening is formed in the busbar. The battery module according to claim 1, wherein at least one of the electrode leads passes through the open portion and is joined to the second portion.

7. The system further includes a busbar frame located between the battery cell stack and the busbar, on which the busbar is mounted. A slit is formed in the busbar frame, The battery module according to claim 1, wherein the electrode lead passes through the slit and is joined to the second portion of the busbar.

8. The battery module according to claim 1, wherein the bead portion protrudes from the intermediate portion of the electrode lead in a direction parallel to the first direction.

9. The battery module according to claim 1, wherein the bead portion is a portion formed by bending the electrode lead at least three times.

10. The battery module according to claim 1, wherein the joint portion, which is the portion where the electrode lead and the second portion are joined, is provided in the portion where the bead portion is connected to the electrode lead.

11. The battery module according to claim 10, wherein a laser is irradiated onto the portion of the bead portion connected to the electrode lead, thereby forming the joint portion.

12. The battery module according to claim 1, further comprising a module frame in which the battery cell stack is housed.

13. A battery pack comprising the battery module described in claim 1.

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