Battery module

Abstract

A battery module according to an embodiment of the present invention may include a plurality of battery cells stacked in a left-right direction, each of the battery cells having an electrode lead protruding forward, a main body, and a bus bar having a joint electrically connected to the electrode lead, the bus bar being configured such that at least a portion of the main body is bent.

Description

Technical Field

[0001] The present invention relates to a battery module.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0084676 filed on July 8, 2022, and Korean Patent Application No. 10-2023-0031777 filed on March 10, 2023, and all the contents disclosed in the specifications and drawings of the applications are incorporated into this application.

Background Art

[0003] The demand for portable electronic products such as notebook computers, video cameras, and mobile phones has increased rapidly, and with the full-scale commercialization of robots, electric vehicles, etc., research on high-performance secondary batteries capable of repeated charge and discharge has been actively conducted.

[0004] Currently commercialized 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 because they have almost no memory effect compared to nickel-based secondary batteries, so they can be charged and discharged freely, have a very low self-discharge rate, and have a high energy density.

[0005] Generally, lithium secondary batteries are classified into can-type secondary batteries in which an electrode assembly is built into a metal can and pouch-type secondary batteries in which an electrode assembly is built into a pouch of an aluminum laminate sheet according to the shape of the exterior material.

[0006] In such pouch-type secondary batteries, the electrical connection between secondary batteries is often configured by directly contacting electrode leads with each other. At this time, in order to connect secondary batteries in parallel, electrode leads of the same polarity are connected to each other, and in order to connect them in series, electrode leads of different polarities are connected to each other.

[0007] Furthermore, busbars may be joined to electrode leads, particularly two or more electrode leads, for electrical connection and / or voltage detection of battery cells. In this case, the connection between the electrode leads and the busbar is often made by welding.

[0008] Battery cell electrode leads may be welded after being bent and in close contact with the busbar. In this case, welding defects may occur depending on the bending quality of the electrode leads. Furthermore, stress may be generated on the electrode leads themselves and on the tab-lead connection points when bending the electrode leads.

[0009] Furthermore, when multiple battery cells are stacked and their respective electrode leads are welded to a single busbar, the length of each electrode lead may vary. This can lead to variations in the length of each electrode lead. Such variations in length can also cause welding defects due to gaps between the stacked electrode leads.

[0010] Furthermore, when battery cells swell, the risk of battery cell tab breakage increases depending on the position of the busbar and electrode leads. In particular, for electrode leads of battery cells on the inside or outermost of the battery module, the bending angle of the battery cell tab can become very large depending on the amount of swelling. Moreover, such an increase in bending angle can cause internal wire breakage problems in the battery cell tab.

[0011] Furthermore, with conventional welding configurations between battery cell electrode leads and busbars, there is a problem in that the stacking procedure of the battery cells is limited in order to ensure weldability, depending on the material of the battery cell electrode leads. [Overview of the project] [Problems that the invention aims to solve]

[0012] The present invention aims to solve the problems described above and other problems.

[0013] Another object of the present invention is to provide a battery module that includes a structure that improves the weldability of electrode leads and busbars.

[0014] Another object of the present invention is to provide a battery module that includes a structure that can reduce scrap costs during the manufacturing of unit battery cells.

[0015] Another object of the present invention is to provide a battery module that includes a structure capable of effectively preventing disconnection of the tabs and electrode leads of the battery cells.

[0016] Another object of the present invention is to provide a battery module that includes a structure that eliminates the bending process of electrode leads.

[0017] Another object of the present invention is to provide a battery module that includes a structure that can increase the degree of freedom of welding methods using a joint structure.

[0018] Another object of the present invention is to provide a battery module that includes a structure capable of preventing assembly / welding defects due to variations in the cutting length of electrode leads.

[0019] Another object of the present invention is to provide a battery module that includes a structure capable of preventing welding defects due to bending quality.

[0020] Another object of the present invention is to provide a battery module that includes a structure in which the quality of the welding can be stably ensured by welding the busbar and the electrode leads with the same material.

[0021] Another object of the present invention is to provide a battery module that includes a structure that can prevent wire breakage due to swelling by maintaining the horizontal position of the tabs and electrode leads of the battery cells, thereby improving ease of assembly. [Means for solving the problem]

[0022] A battery module according to an embodiment of the present invention for achieving the above object may include a plurality of battery cells stacked in the left - right direction, each having an electrode lead protruding forward, a main body portion, and a bus bar having a shape in which at least a part of the main body portion is bent and including a joint portion electrically connected to the electrode lead.

[0023] Also, the electrode lead and the joint portion may be configured to be joined by welding.

[0024] Also, a plurality of joint portions may be formed so as to correspond one - to - one with the electrode leads.

[0025] Also, the electrode lead may be configured to have a flat shape.

[0026] Also, the electrode lead and the joint portion may be configured to be in surface contact.

[0027] Also, the joint portion may be configured to be formed integrally with the main body portion.

[0028] Also, the joint portion may extend in the front - rear direction.

[0029] Also, the joint portion may be formed by cutting at least a part of the main body portion and bending the cut - open part.

[0030] Also, the bus bar includes a hole penetrating the main body portion adjacent to the joint portion, and the diameter of the joint portion may be configured to be smaller than the diameter of the hole.

[0031] Also, the bus bar includes a hole penetrating the main body portion adjacent to the joint portion, and the electrode lead can pass through the hole.

[0032] Also, at least a part of the bus bar may be composed of mutually different metal layers.

[0033] Furthermore, at least a portion of the joint may be composed of different metal layers.

[0034] A battery pack according to the present invention, which aims to achieve the above-mentioned objectives, includes a battery module according to the present invention.

[0035] An automobile according to the present invention, which is intended to achieve the above-mentioned objectives, includes a battery module according to the present invention.

[0036] An energy storage system according to the present invention, for achieving the above-mentioned objectives, includes a battery module according to the present invention. [Effects of the Invention]

[0037] According to at least one embodiment of the present invention, weldability can be improved in a configuration in which electrode leads and busbars are welded together.

[0038] According to at least one embodiment of the present invention, scrap costs can be reduced during the production of unit cells.

[0039] According to at least one embodiment of the present invention, it is possible to effectively prevent breakage of cell tabs or leads.

[0040] According to at least one embodiment of the present invention, the bending process of the cell lead can be omitted. Therefore, the occurrence of stress and welding defects in the cell tab and cell lead can be effectively prevented. Furthermore, according to such an embodiment of the present invention, the manufacturing cost of battery modules and packs can be reduced and the manufacturing process can be simplified.

[0041] According to at least one embodiment of the present invention, the degree of freedom in welding methods using a joint structure can be increased.

[0042] According to at least one embodiment of the present invention, assembly / welding defects due to variations in lead cutting length can be prevented.

[0043] According to at least one embodiment of the present invention, welding defects due to bending quality can be prevented.

[0044] According to at least one embodiment of the present invention, the quality of the welding can be stably ensured by welding the busbar and the electrode lead with the same material.

[0045] According to at least one embodiment of the present invention, maintaining the horizontal position of the cell tab and cell lead prevents wire breakage due to swelling and improves ease of assembly.

[0046] Furthermore, the present invention can have various other effects, which will be explained in each embodiment, or effects that can be easily inferred by those skilled in the art will not be explained.

[0047] The following drawings accompanying this specification illustrate preferred embodiments of the invention and, together with the detailed description of the invention, serve to further illustrate the technical idea of ​​the invention; therefore, the invention should not be construed as being limited solely to what is shown in the drawings. [Brief explanation of the drawing]

[0048] [Figure 1] This is a perspective view showing a battery module according to one embodiment of the present invention. [Figure 2] This diagram shows a partial configuration of a battery module according to one embodiment of the present invention, separated from its original form. [Figure 3] This figure shows a partial configuration of a battery module according to one embodiment of the present invention. [Figure 4] Figure 3 shows a partial configuration of the battery module viewed from one side. [Figure 5] This figure shows a partial configuration of a battery module according to one embodiment of the present invention. [Figure 6] Figure 5 shows a partial configuration of the battery module viewed from one side. [Figure 7] This is a perspective view showing the busbar of a battery module according to one embodiment of the present invention. [Figure 8] This is a perspective view showing the busbar of a battery module according to another embodiment of the present invention. [Figure 9] This is a perspective view showing the busbar of a battery module according to yet another embodiment of the present invention. [Figure 10] A perspective view showing a battery module according to another embodiment of the present invention. [Figure 11] This is a perspective view showing a battery module according to yet another embodiment of the present invention. [Modes for carrying out the invention]

[0049] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims shall not be interpreted in their usual and dictionary sense, but rather in a sense and concept appropriate to the technical idea of ​​the present invention, in accordance with the principle that the inventor himself may appropriately define the concept of terms in order to best describe the invention.

[0050] Therefore, it should be understood that the configurations shown in the embodiments described herein represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention, and that there are various equivalents and modifications that can be substituted therein at the time of filing this application.

[0051] Figure 1 is a perspective view showing a battery module according to one embodiment of the present invention. Figure 2 is a diagram showing a partial configuration of the battery module according to one embodiment of the present invention. Figure 3 is a diagram showing a partial configuration of the battery module according to one embodiment of the present invention. Figure 4 is a side view of a partial configuration of the battery module of Figure 3. For convenience of explanation, Figure 4 is shown as a cross-section only with respect to the busbar 200, and the body 110 of the battery cell 100 is shown schematically. Referring to Figures 1 to 4, the battery module may be configured to include a plurality of battery cells 100 and a busbar 200.

[0052] Referring to Figures 1 and 2, the battery module may include a frame 300 that provides an internal space 301. The frame 300 may have an open front and rear configuration. End covers 400 may be provided on the front and rear sides of the frame 300. The end covers 400 can be coupled to the open portions of the frame 300. In this case, the frame 300 and the end covers 400 may be joined by welding.

[0053] A battery module is also called a cell assembly or battery pack. For example, if a battery module according to one embodiment of the present invention further includes components such as a BMS, busbar assembly, case, relay, current sensor, etc., it is also called a battery pack.

[0054] Multiple battery cells 100 may be provided. Each battery cell 100 may include a body 110 and electrode leads 120 extending from or protruding from the body 110. Each of the multiple battery cells 100 may be configured such that at least one electrode lead 120 protrudes forward or along the +Z axis from the body 110. Alternatively, each of the multiple battery cells 100 may be configured such that at least one electrode lead 120 protrudes rearward or along the -Z axis from the body 110. Multiple battery cells 100 may be stacked in the left-right direction or along the X axis. The battery cells 100 may be housed inside a frame 300.

[0055] Multiple battery cells 100 may be pouch-type rechargeable batteries. Such pouch-type rechargeable batteries may be configured in which an electrode assembly and an electrolyte are housed inside a pouch outer casing. The pouch outer casing may be configured to seal the edges of two pouches with the electrode assembly and electrolyte housed inside. The pouch-type rechargeable battery may be configured in which the housing is located in the center and the sealing part surrounds it. The pouch-type rechargeable battery may be configured in a square shape with four corners, and three or four of the four corners can be sealed.

[0056] The busbar 200 can be electrically connected to the electrode leads 120. The electrode leads 120 of multiple battery cells 100 can each be physically and / or electrically connected to the busbar 200. Depending on the connection configuration of the busbar 200 and the electrode leads 120, the multiple battery cells 100 can be electrically connected in series or in parallel.

[0057] The busbar 200 may extend in the left-right direction. The longitudinal direction of the busbar 200 may be perpendicular to the direction in which the electrode leads 120 protrude. The busbar 200 may also be located between the end cover 400 and the multiple battery cells 100. Furthermore, the busbar 200 may be housed in the space formed by the frame 300 and the end cover 400.

[0058] The busbar 200 may be configured to include a main body 210 and a connecting portion 220. The main body 210 may be configured in the shape of a bar and / or plate. The main body 210 may be configured to extend in length as the number of battery cells 100 connected to the busbar 200 increases. The main body 210 may be made of a metallic material.

[0059] The joint 220 may be configured such that at least a portion of the main body 210 is bent. Alternatively, the joint 220 may be configured to extend from or protrude from the main body 210. The joint 220 may be physically and / or electrically connected to the electrode lead 120. Referring to Figure 3, for example, the joint 220 may be bent forward or in the +Z axis direction. The joint 220 may be positioned opposite the electrode lead 120.

[0060] According to this configuration of the present invention, since the joint 220 is formed by bending, the electrode lead 120 can be physically and / or electrically connected to the joint without being bent or broken. This minimizes the tension and stress applied to the electrode lead 120. It also prevents damage to the electrode lead 120 and breakage.

[0061] Furthermore, according to this configuration of the present invention, the electrode lead 120 and the tab of the battery cell 100 can be connected, attached, fixed, or joined horizontally. That is, the electrode tab and the electrode lead 120 are joined by surface contact inside the battery cell 100, and such a joined portion can be kept flat without bending. Therefore, the possibility of disconnection or damage to the battery cell 100 can be reduced.

[0062] Furthermore, with this configuration of the present invention, when swelling occurs in the battery cell 100, even if the battery cell 100 expands in the left-right direction, the tab pulling of the electrode lead 120 can be minimized.

[0063] Furthermore, according to the above configuration of the present invention, since the joint portion 220 is formed by bending the main body portion 210, the manufacturing of the busbar becomes easier, and manufacturing time and costs can be reduced. Therefore, the productivity of busbars and battery modules including them can be improved.

[0064] Referring to Figures 3 and 4, the electrode lead 120 and joint 220 of the battery module according to one embodiment of the present invention may be configured to be joined by welding. For example, the electrode lead 120 and joint 220 can be joined by welding using a lead joint J method.

[0065] According to this configuration of the present invention, the electrode lead 120 and the joint 220 are joined by welding, eliminating the need for additional parts and processes for joining. This simplifies the process compared to other joining methods.

[0066] Furthermore, with this configuration of the present invention, welding is performed with the electrode lead 120 facing the joint 220 without being bent, thus improving weldability.

[0067] Referring to Figures 3 and 4, multiple junctions 220 of the battery module according to one embodiment of the present invention can be formed so as to correspond one-to-one with the electrode leads 120. For example, referring to Figures 3 and 4, each electrode lead 120 can be coupled to one junction 200. Furthermore, each electrode lead 120 can be configured to have the same length in the front-to-back direction or in the Z-axis direction. That is, the entire battery cell 100 included in the battery module according to the present invention can be configured so that the lengths of the electrode leads 120 protruding outward from the body 110 are all the same. In this case, the spacing between the multiple battery cells 100 and the spacing between the multiple junctions 200 can be configured to be the same as each other.

[0068] Conventionally, multiple electrode leads 120 were connected to a busbar 200 by forming a single welded joint J. In this case, the degree of freedom in welding was sometimes limited by the metal material composition of the electrode leads 120. For example, when welding aluminum electrode leads 120 and copper electrode leads 120 together, the arrangement procedure of the electrode leads 120 may be restricted in order to ensure weldability. This may result in restrictions on the arrangement procedure of multiple battery cells 100, or constraints requiring the production of electrode leads 120 of different lengths.

[0069] However, according to the above embodiment of the present invention, since one joint J connects one joint portion 220 and one electrode lead 120, weldability can be improved.

[0070] Furthermore, with this configuration of the present invention, the electrode leads 120 of each battery cell 100 are configured to be the same shape or the same length, thereby improving the productivity of the battery module.

[0071] Referring to Figures 3 and 4, the electrode lead 120 of the battery module according to one embodiment of the present invention may be configured to have a flattened shape.

[0072] Furthermore, the electrode lead 120 may be configured to have a flattened shape as a whole. That is, the electrode lead 120 may be configured to have a planar shape as a whole without being bent or broken. Also, each of the multiple electrode leads 120 may have a flattened shape and / or a planar shape.

[0073] As a more specific example, referring to the embodiment in Figure 4, the electrode lead 120 extends outward from the body 110 of the battery cell 100, but can extend linearly parallel to the Z-axis without being bent.

[0074] Conventionally, multiple electrode leads 120 were connected to the busbar 200 by forming a single welded joint. In this case, at least some of the multiple electrode leads 120 could be bent, which could damage the electrode leads 120.

[0075] However, according to the above embodiment of the present invention, since the electrode lead 120 has a flattened shape without being bent or broken as a whole, damage to the electrode lead 120 or breakage can be prevented.

[0076] Furthermore, this configuration of the present invention eliminates the step of bending the electrode leads 120, thereby improving the productivity of the battery module.

[0077] Furthermore, a busbar 200 with such a configuration as the present invention is sometimes called a bending-free busbar (200), in the sense that the electrode lead 120 can be configured so that it is not bent for welding.

[0078] Referring to Figures 3 and 4, the electrode leads 120 and the joint 220 of the battery module according to one embodiment of the present invention may be configured to be in surface contact. The joint 220 may be configured to be flattened by bending at least a portion of the main body 210 which has a bar or plate shape. The joint 220 and the electrode leads 120 may be physically and / or electrically connected and in surface contact.

[0079] With this configuration of the present invention, the contact area or bonding area between the joint 220 and the electrode lead 120 is increased, which prevents assembly defects or welding defects caused by variations in the length of the electrode lead 120. In this case, by ensuring that the contact area between the joint 220 and the electrode lead 120 is stably maintained at a certain level or higher, electrical resistance and the resulting power loss and heat generation can be effectively reduced.

[0080] Figure 5 shows a partial configuration of a battery module according to another embodiment of the present invention. Figure 6 is a side view of a partial configuration of the battery module of Figure 5. For convenience of explanation, Figure 6 is shown as a cross-section only with respect to the busbar 200, and the body 110 of the battery cell 100 is shown schematically. Referring to Figures 3 to 6, the joint 220 of the battery module according to one embodiment of the present invention may extend in the front-rear direction.

[0081] The joint 220 may extend forward or in the +Z axis direction depending on the bending direction. Alternatively, the joint 220 may extend backward or in the -Z axis direction depending on the bending direction. Alternatively, at least a portion of the joint 220 may extend forward or in the +Z axis direction, and the remainder may extend backward or in the -Z axis direction. When the joint 220 extends backward or in the -Z axis direction, the length of the electrode lead 120 may be configured to be shorter than when the joint 220 extends forward or in the +Z axis direction.

[0082] In particular, the joint portion 220 may be configured by bending it substantially perpendicular to the main body portion 210. For example, referring to the embodiments in Figures 3 to 6, if the main body portion 210 is configured parallel to the XY plane, the joint portion 220 may be configured in a form parallel to the XZ plane so as to be perpendicular to such a main body portion 210.

[0083] Furthermore, in such embodiments, the joint portion 220 may be configured in a shape parallel to the longitudinal direction of the battery cell 100. For example, in the embodiment shown in Figure 6, the battery cell 100 can be said to be formed to be elongated in the Z-axis direction, and the joint portion 220 of the busbar 200 can also be said to be formed to extend elongated in the Z-axis direction.

[0084] According to this configuration of the present invention, the electrode lead 120 can selectively extend forward or backward, thereby increasing the design flexibility of the battery module.

[0085] In particular, in the above embodiment, the electrode lead 120 can continuously maintain a straight shape not only in the portion that protrudes outward at the sealing portion of the body 110, but also in the portion that is welded to the joint portion 220 of the busbar 200.

[0086] This facilitates welding the electrode lead 120 to the joint 220, while more effectively preventing damage to the electrode lead 120.

[0087] With this configuration of the present invention, the electrode lead 120 is bent backward, eliminating the need for it to protrude forward from the busbar 200. This allows the electrode lead 120 and the joint 220 to be located inside the busbar 200, providing more stable protection from the outside. It also increases the design flexibility in the space in front of the busbar 200. Furthermore, the electrode lead 120 can be selectively welded to either one of the two sides of the backward-bent joint 200. In this case, the electrode lead 120 can be welded to either one of the two sides of the joint 220 in a way that minimizes bending.

[0088] Figure 7 is a perspective view showing a busbar 200 of a battery module according to one embodiment of the present invention. Figure 8 is a perspective view showing a busbar 200 of a battery module according to another embodiment of the present invention. Figure 9 is a perspective view showing a busbar 200 of a battery module according to yet another embodiment of the present invention. Referring to Figures 7 to 9, the joint portion 220 according to one embodiment of the present invention may be configured to be formed integrally with the main body portion 210.

[0089] With this configuration of the present invention, the joint portion 220 does not require separate part processing, thus improving the productivity of the battery module. Furthermore, in this case, since structures and fastening members for connecting the joint portion 220 to the main body portion 210 are unnecessary, the bonding force between the joint portion 220 and the main body portion 210 can be stably ensured. In addition, contact resistance between the joint portion 220 and the main body portion 210 can be eliminated or reduced.

[0090] Referring to Figures 7 to 9, the joint portion 220 of the busbar 200 of the battery module according to one embodiment of the present invention may be configured such that at least a portion of the main body portion 210 is cut open and the cut portion is bent to form the joint portion.

[0091] Referring to Figure 7, at least a portion of the main body 210 can be cut. The cut line C can penetrate the main body 210. The cut line C can form three of the four sides of a rectangle. In this case, the width W of the cut portion can be the same as the width of the electrode lead 120, or it can be formed to be larger than the width of the electrode lead 120.

[0092] Referring to Figure 8, the cut portion of the main body 210 can be bent forward or in the +Z axis direction. Referring to Figure 7, the cut portion of the main body 210 can be bent backward or in the -Z axis direction. The cut portion of the main body 210 can be bent to form a joint 220. The joint 220 can be bent or extended in a direction perpendicular to the main body 210.

[0093] According to this configuration of the present invention, the joint portion 220 does not require separate part processing and can therefore be formed in a relatively simple process. This improves the productivity of battery modules.

[0094] Referring to Figures 7 to 9, the busbar 200 of a battery module according to one embodiment of the present invention includes a hole 211 adjacent to the joint 220 and penetrating the main body 210, and the diameters D2 and D4 of the joint 220 may be smaller than the diameters D1 and D3 of the hole 211.

[0095] The hole 211 may be formed by bending the joint 220. The hole 211 may be formed in a square shape. The diameters D1 and D3 of the hole 211 may refer to the maximum diameters D1 and D3 of the hole 211. The diameters D2 and D4 of the joint 220 may refer to the maximum diameters D2 and D4 of the joint. In this case, the joint 220 may refer to a flat plate portion. The diameters D2 and D4 of the joint 220 may be smaller than the diameters D1 and D3 of the hole 211. The diameters D2 and D4 of the joint 220 may be formed smaller than the diameters D1 and D3 of the hole 211 by the width of the incision line C.

[0096] Furthermore, when the bent joint 220 is flattened, the joint 220 as a whole can be accommodated in the hole 211.

[0097] According to this configuration of the present invention, when a part of the main body 210 is bent, the formation of the joint 220 and the formation of the hole 211 can be performed simultaneously. This simplifies the manufacturing process of the busbar 200 and improves the productivity of the battery module.

[0098] Referring to Figures 7 and 8, the busbar 200 of a battery module according to one embodiment of the present invention may include a hole 211 adjacent to the joint 220 and penetrating the main body 210, and the electrode lead 120 may be configured to pass through the hole 211.

[0099] At least a portion of the electrode lead 120 can pass through the hole 211 and connect to the joint 220. In this case, the electrode lead 120 and the joint 220 are sometimes referred to as a lead insert joint (J) structure.

[0100] According to this configuration of the present invention, when a part of the main body 210 is bent, the formation of the joint 220 and the formation of the hole 211 can be performed simultaneously. This simplifies the manufacturing process of the busbar 200 and improves the productivity of the battery module.

[0101] Figure 10 is a perspective view showing a battery module according to another embodiment of the present invention. Figure 11 is a perspective view showing a battery module according to yet another embodiment of the present invention. For convenience of explanation, Figures 10 and 11 are shown as cross-sections only with respect to the busbar 200, and the body 110 of the battery cell 100 is shown schematically. Referring to Figures 10 and 11, at least a portion of the busbar 200 of the battery module according to one embodiment of the present invention may be composed of different metal layers M1 and M2.

[0102] The busbar 200 may be made of clad metal material. For example, the busbar 200 may be made of two metal layers M1 and M2. The two metal layers M1 and M2 may be made of different materials. In particular, the busbar 200 may be configured to include a metal layer made of the same material as the negative electrode lead 120 and a metal layer made of the same material as the positive electrode lead 120. For example, one side of the busbar 200 may be made of aluminum and the other side of the busbar may be made of copper.

[0103] According to this configuration of the present invention, the electrode lead 120 can be welded to the metal layers M1 and M2 of the busbar 200, which have a metal material similar to that of the electrode lead 120. This improves the weldability between the busbar 200 and the electrode lead 120. Furthermore, this may increase the degree of freedom in the arrangement of the multiple battery cells 100.

[0104] Referring to Figures 10 and 11, at least a portion of the joint 220 of the battery module according to one embodiment of the present invention may be composed of different metal layers M1 and M2. The main body 210 and the joint 220 of the busbar 200 are formed integrally, and the main body 210 and the joint 220 may be composed of the same clad metal material.

[0105] Referring to Figure 10, the joint 220 can be bent to the rear or in the -Z axis direction. The right side of the joint 220 may be composed of a first metal layer M1, and the left side of the joint 220 may be composed of a second metal layer M2. In this case, the electrode lead 120 can be selectively welded to the first metal layer M1 or the second metal layer M2 of the joint 220. For example, if the first metal layer M1 is made of aluminum and the electrode lead 120 is made of aluminum, the electrode lead 120 can be welded to the first metal layer M1. Also, if the second metal layer M2 is made of copper and the electrode lead 120 is made of copper, the electrode lead 120 can be welded to the second metal layer M2.

[0106] According to this configuration of the present invention, the electrode lead 120 can be selectively welded to a joint 220 having a metal material similar to the metal material of the electrode lead 120. This improves the weldability between the busbar 200 and the electrode lead 120.

[0107] Furthermore, with this configuration of the present invention, the curvature of the electrode lead 120 can be minimized regardless of whether the electrode lead 120 is welded to the left or right side of the joint 220.

[0108] Referring to Figure 11, a portion of the joint 220 may be bent backward or in the -Z axis direction, and the remainder of the joint 220 may be bent forward or in the +Z axis direction. The electrode lead 120 can be selectively welded to the joint 220 bent forward or in the +Z axis direction, or to the joint 220 bent backward or in the -Z axis direction. That is, the joint 220 may be bent in the +Z axis direction or the -Z axis direction depending on the material of the electrode lead 120 being welded. In particular, when both the positive and negative electrode leads are welded to a single busbar 200, joints 220 bent in opposite directions relative to the main body 210 may be provided on a single busbar 200.

[0109] The electrode lead 120 can be welded to the right side of the joint 220, which is bent forward or in the +Z axis direction, or to the second metal layer M2. In this case, the metal material of the electrode lead 120 and the metal material of the second metal layer M2 may be the same material.

[0110] Furthermore, the electrode lead 120 can be welded to the right side of the joint 220, which is bent to the rear or in the -Z axis direction, or to the first metal layer M1. In this case, the metal material of the electrode lead 120 and the metal material of the first metal layer M1 may be the same material.

[0111] In this case, the length of the electrode lead 120 of the battery cell 100 welded to the joint 220 bent forward or in the +Z axis direction may be longer than the length of the electrode lead 120 of the battery cell 100 welded to the joint 220 bent backward or in the -Z axis direction.

[0112] According to this configuration of the present invention, the electrode lead 120 can be selectively welded to a joint 220 having a metal material similar to the metal material of the electrode lead 120. This improves the weldability between the busbar 200 and the electrode lead 120.

[0113] Furthermore, this configuration of the present invention increases the degree of freedom in the stacking procedure of the battery cells 100. The bending direction of the joint portion 220 can be selectively configured to correspond to the stacking procedure of the battery cells 100.

[0114] Furthermore, with this configuration of the present invention, the curvature of the electrode lead 120 can be minimized regardless of whether the electrode lead 120 is welded to the joint portion bent forward or in the +Z axis direction, or to the joint portion 220 bent backward or in the -Z axis direction.

[0115] The battery pack according to the present invention may include the battery module according to the present invention as described above. In addition to the battery module according to the present invention described above, the battery pack according to the present invention may further include various other components, such as components of a battery pack known at the time of filing of the present invention, such as a BMS, busbars, pack case, relays, and current sensors.

[0116] An automobile according to the present invention may include the battery module according to the present invention described above. The battery module according to the present invention can be applied to automobiles such as electric vehicles and hybrid vehicles. In addition to such a battery module, an automobile according to the present invention may further include various other components included in the automobile, such as a vehicle body, a motor, and control devices such as an ECU (electronic control unit).

[0117] The energy storage system (ESS) according to the present invention may include the battery module according to the present invention as described above. In addition to such a battery module, the energy storage system according to the present invention may further include other components included in the energy storage system, such as a sensor for sensing the state of the battery module, a fire suppression module for controlling thermal events, a DC part, an AC part, and a BSC part.

[0118] On the other hand, while terms indicating directions such as up, down, left, right, front, and back are used in this specification, these terms are for convenience of explanation and it will be obvious to those skilled in the art that they can change depending on the position of the object in question, the position of the observer, etc.

[0119] As described above, the present invention has been explained with limited embodiments and drawings, but the present invention is not limited thereto, and it goes without saying that any person with ordinary skill in the art to which the present invention belongs can make various modifications and variations within the equivalent scope of the technical idea of ​​the present invention and the following claims. [Explanation of Symbols]

[0120] 100 battery cells 110 Body 120 electrode leads 200 bus bar 210 Main body 211 hole 220 Joint 300 frames 301 Interior space 400 End Cover C incision line D1~D4 Maximum diameter J-joint M1 1st metal layer M2 2nd metal layer W width

Claims

1. Each battery cell has an electrode lead that protrudes forward, and multiple battery cells are stacked in the left-right direction, A battery module comprising: a main body; and a busbar having a shape in which at least a portion of the main body is bent to the rear and having a junction that is electrically connected to the electrode leads.

2. The electrode lead and the joint portion are The battery module according to claim 1, configured to be joined by welding.

3. The aforementioned joint is The battery module according to claim 1, wherein a plurality of electrode leads are formed to correspond one-to-one with the electrode leads.

4. The electrode lead is The battery module according to claim 1, configured to have a flattened shape.

5. The electrode lead and the joint portion are The battery module according to claim 4, configured to be in surface contact.

6. The aforementioned joint is The battery module according to claim 1, configured to be formed integrally with the main body.

7. The aforementioned joint is The battery module according to claim 1, extending in the rearward direction.

8. The aforementioned joint is The battery module according to claim 1, wherein at least a portion of the main body is cut open and the cut portion is bent to form the module.

9. The aforementioned busbar is The joint portion includes a hole that penetrates the main body portion adjacent to the aforementioned joint portion, The diameter of the joint is, The battery module according to claim 1, wherein the diameter is smaller than the diameter of the aforementioned hole.

10. The aforementioned busbar is The joint portion includes a hole that penetrates the main body portion adjacent to the aforementioned joint portion, The electrode lead is The battery module according to claim 1, passing through the aforementioned hole.

11. At least a portion of the bus bar is The battery module according to claim 1, comprising layers of different metals.

12. At least a portion of the joint is The battery module according to claim 11, comprising layers of different metals.

13. A battery pack comprising a battery module according to any one of claims 1 to 12.

14. An automobile comprising a battery module according to any one of claims 1 to 12.

15. An energy storage system comprising a battery module according to any one of claims 1 to 12.

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