Battery module and method for manufacturing battery module

Abstract

The battery module of the present disclosure includes a main body portion that supplies or stores electrical energy and tab portions that protrude from one side of the main body portion, and comprises: a plurality of battery cells stacked in a preset first direction; a module case accommodating the plurality of battery cells; a plurality of first bus bars, which are coupled to any one of first surfaces of the tab portions formed in a second direction in which the tab portions protrude within the module case and in a third direction perpendicular to the first direction and the second direction, and are provided in a number as many as that of the tab portions; and a second bus bar which extends in the first direction inside the module case and is coupled to at least some of the plurality of first bus bars to electrically connect the plurality of battery cells to the outside.

Description

Battery module and battery module manufacturing method

[0001] The present disclosure relates to a battery module and a method for manufacturing the same. Specifically, it relates to a battery module and a method for manufacturing the same with improved stability and assembly.

[0002] Secondary batteries convert electrical energy into chemical energy, allowing them to be stored and reused multiple times through charging and discharging. Due to their economical and environmentally friendly properties, secondary batteries are widely used across various industries. Lithium secondary batteries, in particular, are widely used in portable devices requiring high energy density, as well as in various industries.

[0003] To achieve high capacity and high output performance, multiple secondary batteries can be grouped together to form a battery assembly (e.g., a battery module or battery pack). To increase the energy density of the battery assembly, it is necessary to minimize wasted internal space.

[0004] When assembling multiple batteries and busbars, a significant amount of wasted space can exist. Active research is underway to minimize this wasted space to increase the energy density and enhance the stability of battery assemblies.

[0005] The problem that the present disclosure seeks to solve is to improve energy density by eliminating wasted space inside a battery assembly.

[0006] In addition, the present disclosure improves the electrical connection performance between a busbar assembly and a battery cell.

[0007] In addition, the present disclosure provides a battery module and a method for manufacturing a battery module with reduced manufacturing cost and improved manufacturing efficiency.

[0008] In addition, the present disclosure can be widely applied in green technology fields such as electric vehicles, battery charging stations, and solar and wind power generation using batteries.

[0009] In addition, the present disclosure can be used in eco-friendly electric vehicles, hybrid vehicles, etc. to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0010] The battery module of the present disclosure includes a main body for supplying or storing electric energy and a tab portion protruding from one side of the main body portion, and a plurality of battery cells stacked along a first direction set in advance; a module case for accommodating the plurality of battery cells; a plurality of first bus bars that are coupled to one side of the tab portion formed along a second direction in which the tab portion protrudes within the module case and a third direction perpendicular to the first direction and the second direction, and are provided in the same number as the number of tab portions; and a second bus bar that extends within the module case along the first direction and is coupled to at least a portion of the plurality of first bus bars to electrically connect the plurality of battery cells to the outside.

[0011] The free end of the above tab portion can be positioned toward the above main body portion.

[0012] The tab portion includes a first region coupled to the first bus bar and a second region connecting the first region and the main body portion, and at least a portion of the first region and at least a portion of the second region may be provided in parallel.

[0013] The above tab portion can be formed by bending.

[0014] The above first region can be integrally connected with the above second region.

[0015] The first bus bar includes a first plate coupled to the tab portion; and a second plate coupled to the second bus bar and vertically provided at one edge of the first plate; wherein the first plate is provided parallel to the tab portion and can be joined to each other.

[0016] The second bus bar includes a connecting plate that can be in contact with one surface of the second plate; and a slit that is open to one side; and the first plate is inserted into the slit, and one surface of the second plate and one surface of the connecting plate can be in contact.

[0017] The above first bus bar can be connected to the above second bus bar through brazing welding.

[0018] The above first busbar and the above second busbar may include the same material.

[0019] The module case may further include an insulating part containing an insulating material inside the module case.

[0020] The present disclosure relates to a method for manufacturing a battery module, comprising a main body for supplying or storing electric energy, a tab portion protruding from one side of the main body portion, a plurality of battery cells stacked along a first direction set in advance, and a busbar assembly for electrically connecting the plurality of battery cells, the method comprising: a first joining step of joining a first busbar of the busbar assembly to one side of the tab portion formed along a second direction, which is a protruding direction of the tab portion, and a third direction perpendicular to the first direction and the second direction; and a second joining step of connecting the first busbar to a second busbar of the busbar assembly extending along the second direction.

[0021] The method may further include a tab bending step of bending the tab so that the free end of the tab faces the main body.

[0022] In the above tab bending step, the tab can be bent twice.

[0023] The above first joining step can be performed by placing the first plate of the first busbar parallel to the tab portion and joining the first busbar and the first plate by cold joining.

[0024] The above first joining step can join the first bus bar to the first plate through clinching joining.

[0025] The second joining step may include an insertion step of inserting the second plate of the first bus bar into a slit open on one side of the second bus bar, and a contact step of bringing one surface of the second plate of the first bus bar into contact with one surface of the connecting plate of the second bus bar.

[0026] The above insertion step allows the second bus bar to move along the third direction so that the first plate can be inserted into the slit.

[0027] The above second joining step can join the first bus bar to the second bus bar through brazing welding.

[0028] The second joining step can weld the second plate and the second bus bar by supplying a filler metal to an area where the second plate and the second bus bar face each other along the third direction.

[0029] The above module case may further include an insulation insertion step of inserting an insulation part including an insulation material into the inside.

[0030] According to one embodiment of the present disclosure, energy density can be improved by eliminating wasted space inside a battery assembly.

[0031] Additionally, the present disclosure can improve the electrical connection performance between a busbar assembly and a battery cell.

[0032] In addition, the present disclosure can provide a battery cell and a battery cell manufacturing method with reduced manufacturing cost and improved manufacturing efficiency.

[0033] FIG. 1 illustrates a battery cell according to one embodiment of the present disclosure.

[0034] FIG. 2 is a simplified exploded view of a battery module according to one embodiment of the present disclosure.

[0035] FIGS. 3 to 7 illustrate a joint structure of a battery cell and a first bus bar according to one embodiment of the present disclosure.

[0036] FIGS. 8 to 12 illustrate a joint structure of a first bus bar and a second bus bar according to one embodiment of the present disclosure.

[0037] FIG. 13 illustrates an insulation member according to one embodiment of the present disclosure.

[0038] FIG. 14 and FIG. 15 briefly illustrate the sequence of a battery module manufacturing method according to one embodiment of the present disclosure.

[0039] Hereinafter, the present disclosure will be described in detail with reference to the attached drawings. However, these are merely exemplary and the present disclosure is not limited to the specific embodiments described as examples.

[0040] Certain terms used in this specification are for convenience of explanation only and are not intended to limit the illustrated embodiments.

[0041] For example, expressions such as "same" and "same as" not only indicate a strictly identical state, but also indicate a state in which there is a difference in tolerance, or the degree to which the same function is obtained.

[0042] For example, expressions indicating relative or absolute arrangements such as “in which direction,” “along which direction,” “parallel,” “perpendicular,” “centered,” “concentric,” or “coaxial” not only strictly indicate such arrangements, but also indicate a state of relative displacement with an angle or distance that allows for tolerance, or the degree to which the same function is obtained.

[0043] In order to explain the present disclosure, the following description is based on a spatial orthogonal coordinate system with mutually orthogonal X-axis, Y-axis, and Z-axis. Each axis direction (X-axis direction, Y-axis direction, Z-axis direction) means both directions in which each axis extends.

[0044] The X-direction, Y-direction, and Z-direction mentioned below are for the purpose of explanation so that the present disclosure can be clearly understood, and it is of course possible to define each direction differently depending on where the standard is set.

[0045] The use of terms such as "first," "second," and "third" before the components mentioned below is intended solely to avoid confusion regarding the components they refer to, and has no bearing on the order, importance, or dominant-subordinate relationship between the components. For example, an invention can be implemented that includes only a second component without a first component.

[0046] As used herein, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0047] FIG. 1 illustrates a battery cell (10) according to one embodiment of the present disclosure, and FIG. 2 illustrates a simplified exploded view of a battery module (1) according to one embodiment of the present disclosure.

[0048] The battery cell (10) described herein refers to a secondary battery that can be repeatedly used by charging and discharging electrical energy. For example, it may refer to a lithium secondary battery or a lithium ion battery, but is not limited thereto. As another example, it may refer to an all-solid-state battery.

[0049] The battery cell (10) may be classified into a pouch-type secondary battery, a prismatic secondary battery, or a cylindrical secondary battery depending on its shape. In this specification, a pouch-type secondary battery is illustrated as an example for convenience of explanation, but the present invention is not limited thereto.

[0050] Meanwhile, the battery module (1) described in this specification refers to a battery assembly in which battery cells (10) are grouped in groups of one or more and placed in a case to protect them from external shock, heat, vibration, etc. and to have high output and high capacity characteristics.

[0051] The battery cell (10) may include a main body (11) and a tab portion (12). The main body (11) may supply or store electrical energy. The main body (11) may include an electrode assembly. The electrode assembly may include a positive electrode, a negative electrode, and a separator. The electrode assembly may include a positive electrode, a negative electrode, and a separator. The electrode assembly may be classified into a stacking type, a winding type, a stack-folding type, and a Z-stacking type depending on the method in which the positive electrode, the negative electrode, and the separator are stacked. The battery cell (10) of the present disclosure is not limited to any one stacking method and may include an electrode assembly stacked in various ways.

[0052] The positive electrode and the negative electrode may include a current collector. The positive electrode may include a positive current collector, and the negative electrode may include a negative current collector. The current collector may include a known conductive material that does not cause a chemical reaction within a lithium secondary battery. For example, the current collector may include any one of stainless steel, nickel (Ni), aluminum (Al), titanium (Ti), copper (Cu), and alloys thereof, and may be provided in various forms such as a film, a sheet, or a foil.

[0053] The positive electrode and the negative electrode may include active materials. The positive electrode may include a positive electrode active material, and the negative electrode may include a negative electrode active material. The positive electrode active material may be a material into which lithium ions can be inserted and deintercalated, and the negative electrode active material may be a material into which lithium ions can be inserted and deintercalated. For example, the positive electrode active material may be a lithium metal oxide, and the negative electrode active material may be a carbonaceous material such as crystalline carbon, amorphous carbon, a carbon composite, or carbon fiber, a lithium alloy, silicon (Si), or tin (Sn).

[0054] Additionally, the positive and negative electrodes may further include a binder and a conductive material, respectively, to improve mechanical stability and electrical conductivity.

[0055] The separator can be configured to prevent electrical short-circuiting between the anode and cathode and to allow ion flow. The type of separator is not particularly limited, but may include a porous polymer film. For example, the separator may include a porous polymer film or a porous nonwoven fabric.

[0056] The tab portion (12) may protrude from one side of the main body portion (11). The tab portion (12) may protrude from either side of the main body portion (11). The tab portion (12) may electrically connect the battery cell (10) to the outside. The tab portion (12) may be connected to the positive and negative electrodes, respectively. The tab portion (12) may include a positive tab (12a) connected to the positive electrode and a negative tab (12b) connected to the negative electrode.

[0057] In an embodiment, the positive and negative tabs may protrude in different directions. For example, referring to FIG. 1, the positive tab may protrude toward one side of the main body (11) along the X direction, and the negative tab may protrude toward the other side of the main body (11) along the X direction. In another embodiment, the positive and negative tabs may protrude toward the same direction.

[0058] In the present disclosure, for convenience of explanation, the second direction in which the tab portion (12) protrudes can be defined as the X direction.

[0059] A battery module (1) may include a plurality of battery cells (10). The plurality of battery cells (10) may be stacked along a preset first direction. Referring to FIG. 2, the plurality of battery cells (10) may be stacked along the Y direction. In the present disclosure, for convenience of explanation, the first direction may be defined as the Y direction. In addition, the third direction refers to a direction perpendicular to the first and second directions. Therefore, the third direction may be defined as the Z direction.

[0060] A plurality of battery cells (10) can be stacked in such a manner that one side of the main body (11) of one battery cell (10) faces one side of the main body (11) of another battery cell (10). The direction in which the battery cells (10) are stacked can be formed perpendicular to the direction in which the tab portion (12) protrudes. This allows for efficient use of the space of the battery module (1) and maximization of the energy density.

[0061] The battery module (1) includes a module case (2) that accommodates a plurality of battery cells (10). The module case (2) can accommodate a plurality of battery cells (10) inside. The module case (2) can cover the plurality of battery cells (10) from the outside. For example, the module case (2) can be provided in a hexahedral shape.

[0062] The module case (2) may include a lower cover (4) that supports the battery cell (10). The module case (2) may include an upper cover (3) that covers the internal storage space by being combined with the lower cover (4).

[0063] The low cover (4) may include a lower body (5) that supports the bottom surface of a plurality of battery cells (10) and a side body (6) that extends from a corner region of the lower body (5) to support the side surfaces of the plurality of battery cells (10). For example, referring to FIG. 2, a battery cell (10) may be positioned on the lower body (5). The side body (6) may extend upward from opposite corners of the lower body (5). The lower body (5) and the side body (6) may be connected to form a channel shape, and the battery cell (10) may be positioned inside. The upper cover (3) may be combined with the low cover (4). The upper cover (3) may be combined with the low cover (4) to form a hexahedral shape with both sides open.

[0064] The module case (2) may further include a front cover (7) and an end cover (8). The end cover (8) may be combined with the low cover (4). The end cover (8) may be combined with the upper cover (3). The front cover (7) may be combined with the low cover (4). The front cover (7) may be combined with the upper cover (3). Ultimately, the end cover (8), the front cover (7), the low cover (4), and the upper cover (3) may be combined to accommodate a battery cell (10) therein.

[0065] Figures 3 to 7 illustrate the joint structure of a battery cell (10) and a first bus bar (30) according to one embodiment of the present disclosure.

[0066] The battery module (1) of the present disclosure may further include a busbar assembly (20, see FIG. 10) electrically connecting a plurality of battery cells (10). The busbar assembly (20) may include a first busbar (30) in contact with a tab portion (12) and a second busbar (40) connecting the first busbar (30) to the outside.

[0067] The busbar assembly (20) may be positioned inside the module case (2). The internal space of the module case (2) may not be efficiently used due to the busbar assembly (20). The present disclosure provides a battery module (1) that can efficiently use the space of the module case (2) by changing the shape of the busbar assembly (20).

[0068] In addition, during the process of connecting the tab portion (12) to the busbar assembly (20), the tab portion (12) may protrude to one side of the busbar assembly. The protruding lengths of the tab portions may be different for each. In order to improve the quality of the battery module (1), it is desirable to minimize the dispersion of the protruding length of the tab portion (12). However, the difficulty in managing the protruding length may lower the manufacturing efficiency. The present disclosure can provide a battery module (1) and a battery module manufacturing method that do not require managing the protruding length of the tab portion (12) by connecting the first busbar (30) and the second busbar (40).

[0069] In addition, when the busbar assembly (20) and the tab portion (12) are formed of dissimilar materials, intermetallic compounds may be generated during welding. For example, when the tab portion (12) including an aluminum material and the busbar assembly (20) including a copper material are welded, intermetallic compounds may be generated. The present disclosure can prevent problems arising from welding dissimilar materials by providing the first busbar (30) and the second busbar (40) with the same material.

[0070] Inside the module case (2), the first bus bar (30) can be coupled with the tab portion (12). Specifically, the first bus bar (30) can be coupled with any one of the surfaces of the tab portion (12). One surface of the tab portion (12) can be provided perpendicular to the first direction, and the free end of the tab portion (12) can be positioned so as to face the outside of the main body portion (11).

[0071] One side of the tab portion (12) can be formed along the second and third directions in which the tab portion (12) protrudes. One side of the tab portion (12) can be positioned to face the direction in which a plurality of battery cells (10) are stacked.

[0072] The tab portion (12) may include a first region (120) that is coupled to the first bus bar (30) and a second region (121) that connects the first region (120) and the main body (11). The first region (120) may be positioned closer to the free end of the tab portion (12) than the second region (121). The second region (121) may be positioned closer to the main body (11) than the first region (120). In an embodiment, the first region (120) and the second region (121) may be provided as virtual regions.

[0073] After the tab portion (12) is coupled to the first bus bar (30), the free end of the tab portion (12) can be changed from a position facing the outside of the main body portion (11) to a position facing the main body portion (11). Through this, at least a portion of the first region (120) and at least a portion of the second region (121) can be provided in parallel.

[0074] Ultimately, the first region (120) and the second region (121) of the tab portion (12) will be formed in a 'U' shape lying sideways. By overlapping the first region (120) and the second region (121), the protruding length of the tab portion (12) is reduced, and the space inside the module can be used efficiently.

[0075] Specifically, one side of the first bus bar (30) and one side of the tab portion (12) can be positioned to face each other and connected. This increases the contact area, thereby improving electrical connectivity and stability.

[0076] Referring to FIGS. 3 to 5, the first bus bar (30) may include a first plate (31) coupled with the tab portion (12) and a second plate (32) coupled with the second bus bar (40). The second plate (32) may be provided vertically at one edge of the first plate (31). The first plate (31) and the second plate (32) may be provided vertically to each other. The second plate (32) may be formed smaller than the first plate (31).

[0077] The first plate (31) of the first bus bar (30) can be connected by contact with the first region (120) of the tab portion (12). The first plate (31) can be provided parallel to the first region (120) and joined to each other.

[0078] The length of the first bus bar (30) along the third direction may be provided to be longer than the length of the electrode tab. This is so that the first bus bar (30) protrudes outward from the electrode tab and is connected to the second bus bar (40). Referring to Fig. 5, the length of the first bus bar (30) along the third direction may be provided to be longer than the length of the tab portion (12).

[0079] The first bus bar (30) can be cold-joined with the tab portion (12). After the first bus bar (30) and the tab portion (12) are arranged in parallel, the first bus bar (30) and the tab portion (12) can be connected by applying pressure to both sides. For example, the first bus bar (30) and the tab portion (12) can be clinched.

[0080] The number of first bus bars (30) may be the same as the number of tab sections (12). Through this, a plurality of tab sections (12) may be connected to a plurality of first bus bars (30), respectively.

[0081] A joining member (400) can join the first bus bar (30) and the tab portion (12). The joining member (400) can include a pressing member (410) and a supporting member (420). The pressing member (410) can pressurize one side of the first bus bar (30) or the tab portion (12). The supporting member (420) can be provided on the opposite side of the pressing member (410) with the first bus bar (30) or the tab portion (12) interposed therebetween. The first bus bar (30) and the tab portion (12) can be clinched by the pressing member (410) and the supporting member (420).

[0082] Referring to FIGS. 4 and 5, the pressing portion (410) may be positioned to face one side of the tab portion (12), and the supporting portion (420) may be positioned to face the other side of the tab portion (12).

[0083] The joint member (400) can pressurize the tab portion (12) at least once. Through this, the stability of the connection between the first bus bar (30) and the tab portion (12) can be improved.

[0084] A recessed portion (310) may be formed by recessing one side of at least one of the tab portion (12) or the first bus bar (30) through clinching joint. For convenience of explanation, the present disclosure assumes that the first bus bar (30) is positioned at the bottom and the tab portion (12) is positioned at the top along the first direction.

[0085] Since the first bus bar (30) contains copper, it can be formed to be stronger and thicker than the tab portion (12). Therefore, it would be advantageous for the first bus bar (30) to be positioned lower. However, if the first bus bar (30) and the tab portion (12) can be connected by cold welding, a structure in which the tab portion (12) is positioned lower would also be possible.

[0086] Looking closely at the cold-bonded structure with reference to Fig. 6, a recessed portion (310) may be formed in the first bus bar (30) located at the bottom. A bottom portion (311) and an inclined portion (312) may be formed on the inner surface of the recessed portion (310). The bottom portion (311) may form the bottom of the recessed portion (310) and may be in contact with the tab portion (12). The diameter of the recessed portion (310) may increase inwardly. In other words, the diameter of the recessed portion (310) may increase inwardly, thereby forming an inclined portion (312).

[0087] At least a portion of the tab portion (12) may be positioned within the recessed portion (310). Specifically, the first region (120) of the tab portion (12) may be positioned within the recessed portion (310). Due to the inclined portion (312), the tab portion (12) positioned within the recessed portion (310) may not be detached. This is because the diameter of the entrance of the recessed portion (310) is smaller than the diameter of the bottom portion (311).

[0088] The recessed portion (310) may further include a groove (313). The groove (313) may be positioned so as to protrude from the edge of the bottom portion (311). The edge of the bottom portion (311) may be subjected to greater pressure than the center, which may result in the formation of the groove (313).

[0089] In another embodiment, if the tab portion (12) is positioned at the bottom and the first bus bar (30) is positioned at the top along the first direction, a recess (310) will be formed in the tab portion (12).

[0090] After the first bus bar (30) and the tab portion (12) are joined, the tab portion (12) can be pressed so that the free end of the first bus bar (30) is positioned along the direction toward the main body (11). In an embodiment, the tab portion (12) can be bent so that the position of the free end of the tab portion (12) can be changed. The tab portion (12) can be bent twice so that the free end of the tab portion (12) is positioned so that it faces 180 degrees opposite directions.

[0091] Referring to Fig. 7, the tab portion (12) can be bent twice to create a “U” shape with the tab portion (12) lying sideways.

[0092] Figures 8 to 12 illustrate the joint structure of the first bus bar (30) and the second bus bar (40) according to one embodiment of the present disclosure.

[0093] After the tab portions (12) provided on the plurality of battery cells (10) are respectively connected to the first bus bar (30), the plurality of battery cells (10) can be stacked along the first direction. Referring to Fig. 8, the battery cells (10) connected to the first bus bar (30) can be stacked along the first direction.

[0094] Referring to Fig. 9, a plurality of first bus bars (30) can be electrically connected by a second bus bar (40). The second bus bar (40) can extend along the first direction within the module case (2). Consequently, the second bus bar (40) can be combined with the first bus bar (30) to electrically connect a plurality of battery cells (10) to the outside.

[0095] In order to be connected to the first bus bar (30), the second bus bar (40) may include a connecting plate (42) and a slit (43). The second bus bar (40) may further include a support body (41) that connects the connecting plate (42) and the slit (43).

[0096] A support body (41) may extend along a first direction and may be formed with a plurality of connection bodies and a plurality of slits (43) on one side. Advantageously, a connection plate (42) may be formed in a direction perpendicular to the first direction in the support body (41). In addition, a plurality of slits (43) may be formed between one connection plate and another connection plate. Through this, a first bus bar (30) may be inserted through the slits (43) and connected to a plurality of connection plates (42).

[0097] Referring to FIGS. 9 and 10, the second bus bar (40) can be slidably coupled with the first bus bar (30). Since one side of the slit (43) is open, the first bus bar (30) can be inserted into the slit (43). For example, the second bus bar (40) can move along the third direction and be coupled with the first bus bar (30).

[0098] Finally, the first plate (31) is inserted into the slit, and one surface of the second plate and one surface of the connecting plate can come into contact.

[0099] When the first bus bar (30) is inserted, the connecting plate (42) and the second plate (32) can come into contact. Through this, the second bus bar (40) and the first bus bar (30) can be electrically connected. To ensure a stable connection, one side of the connecting plate (42) can be provided with a shape corresponding to that of the second plate (32). For example, when the second plate (32) is formed in a rectangular shape, the connecting plate (42) can also be formed in a rectangular shape.

[0100] When the first bus bar (30) is inserted through the slit (43), the plurality of connecting plates (42) can each come into contact with the plurality of second plates (32).

[0101] The first bus bar (30) and the second bus bar (40) can be welded. The first bus bar (30) and the second bus bar (40) can comprise the same material. The first bus bar (30) and the second bus bar (40) can be formed of the same material. This can improve the stability and performance of the welding.

[0102] Specifically, the first bus bar (30) and the second bus bar (40) can be brazed. This is to cover the tolerance that occurs between the first bus bar (30) and the second bus bar (40).

[0103] Referring to Fig. 11, even if the first bus bar (30) is inserted into the slit (43), a plurality of battery cells (10) may be inserted simultaneously, resulting in a slight tolerance. Accordingly, a certain first bus bar (30) may be spaced apart from the second bus bar (40) by a certain distance, resulting in a tolerance. To cover the tolerance, the first bus bar (30) and the second bus bar (40) may be connected through brazing.

[0104] A welding system (not shown) can provide a filler material (200) to an area where the first bus bar (30) and the second bus bar (40) come into contact. The welding system can weld the second plate (32) and the second bus bar (40) by supplying the filler material (200) to an area where the second plate (32) and the second bus bar (40) face each other along a third direction. The filler material (200) can have a lower melting temperature than the first bus bar (30) and the second bus bar (40). For example, the filler material can be a welding wire.

[0105] Additionally, the welding system can provide a heat source. For example, the heat source can be a laser. When the laser is irradiated, the filler metal first melts and then solidifies between the first bus bar (30) and the second bus bar (40), thereby minimizing damage to the first bus bar (30) and the second bus bar (40).

[0106] A weld bead (210) can be formed by welding. The weld bead (210) can be formed between the first bus bar (30) and the second bus bar (40). Specifically, the weld bead (210) can be formed in an area where the second plate (32) and the support body (41) meet. Referring to FIG. 12, the weld bead (210) can extend in one direction from the second plate (32) and the support body (41).

[0107] FIG. 13 illustrates an insulation member (300) according to one embodiment of the present disclosure.

[0108] The battery module (1) of the present disclosure may further include an insulating member (300). The insulating member (300) may include an insulating material. The insulating member (300) may be located inside the module case (2).

[0109] The inside of the battery module (1) may have an air layer formed to form an insulating structure, but the insulating performance of the battery module (1) may be further improved through the insulating portion (300). The thermal conductivity of the insulating portion (300) may be higher than that of air. For example, the insulating portion (300) may include urethane or silicone. The insulating portion (300) may be a silicone liquid type foaming agent.

[0110] Referring to Fig. 13, the insulation part (300) can be located in the insulation area provided between the main body part (11) and the second bus bar (40). Through this, the insulation performance of the battery module (1) is improved, fire propagation is prevented, and thermal runaway can be prepared.

[0111] Hereinafter, a method for manufacturing a battery module (1) according to the present disclosure will be described in detail.

[0112] FIG. 14 and FIG. 15 briefly illustrate the sequence of a method for manufacturing a battery module (1) according to one embodiment of the present disclosure.

[0113] The method for manufacturing a battery module (1) of the present disclosure includes a first joining step (S30) of joining a first busbar (30) of a busbar assembly (20) to one side of a tab portion (12) formed along a second direction, which is a protruding direction of the tab portion (12), and a third direction perpendicular to the first and second directions, and a second joining step (S50) of connecting the first busbar (30) to a second busbar (40) of the busbar assembly (20) extending along the second direction.

[0114] Referring to Fig. 14, a second coupling step (S50) may be performed after the first coupling step (S30). The first coupling step (S30) may connect the tab portion (12) to the first bus bar (30). The second coupling step (S50) may connect the first bus bar (30) and the second bus bar (40). Through this, the battery cell (10) may be electrically connected to the outside.

[0115] The first joining step (S30) may be performed by arranging the first plate (31) of the first bus bar (30) in parallel with the tab portion (12) and joining the first bus bar (30) and the first plate (31). The first joining step (S30) may be performed by cold joining. Specifically, the first joining step (S30) may apply clinching joining.

[0116] Referring to FIG. 15, the second joining step (S50) may include an insertion step (S51) of inserting the second plate (32) of the first bus bar (30) into a slit (43) open on one side of the second bus bar (40), and a contact step (S53) of bringing one surface of the second plate (32) of the first bus bar (30) into contact with one surface of the connecting plate (42) of the second bus bar (40). As described above, the second bus bar (40) may slide toward the first bus bar (30) to make contact with each other. Specifically, the second bus bar (40) may move along the third direction so that the first plate (31) may be inserted into the slit (43).

[0117] The second joining step (S50) can join the first bus bar (30) and the second bus bar (40) through brazing welding. The second joining step (S50) can weld the second plate (32) and the second bus bar (40) by supplying a filler metal to the area where the second plate (32) and the second bus bar (40) face each other along the third direction. This is to cover the tolerance formed between the first bus bar (30) and the second bus bar (40) and thereby improve the stability of the joining and the welding quality.

[0118] Referring back to FIG. 14, the manufacturing method of the present disclosure may further include a tab bending step (S10). The tab bending step (S10) may bend the tab (12) so that the free end of the tab (12) faces the main body (11). Specifically, the tab bending step (S10) may bend any region of the tab (12). For example, the tab bending step (S10) may bend the tab (12) twice. The first joining step (S30) may be performed after the tab bending step (S10).

[0119] The manufacturing method of the present disclosure may further include an insulation insertion step (S70). The insulation insertion step (S70) may insert an insulation part (300) containing an insulation material into the interior of the module case (2). Specifically, the insulation part (300) containing an insulation material may be inserted into an insulation area provided between the main body (11) and the second bus bar (40).

[0120] The present disclosure may be implemented in various forms and modifications, and the scope of the present disclosure is not limited to the embodiments described above. Therefore, if a modified embodiment includes elements of the present disclosure, it should be considered to fall within the scope of the present disclosure.

Claims

1. A plurality of battery cells including a main body for supplying or storing electric energy and a tab protruding from one side of the main body, and stacked along a first direction set in advance; A module case accommodating the plurality of battery cells; A plurality of first bus bars, which are formed along the second direction in which the tab portion protrudes inside the module case and along the third direction perpendicular to the first direction and the second direction, and are combined with one of the surfaces of the tab portion, and are provided in the same number as the number of tab portions; and A battery module including a second bus bar extending along the first direction inside the module case and electrically connecting the plurality of battery cells to the outside by combining with at least a portion of the plurality of first bus bars.

2. In paragraph 1, A battery module in which the free end of the tab portion is positioned toward the main body portion.

3. In paragraph 2, The tab portion includes a first region that is coupled to the first bus bar and a second region that connects the first region and the main body portion, A battery module in which at least a portion of the first region and at least a portion of the second region are provided in parallel.

4. In paragraph 3, A battery module formed by bending the above tab portion.

5. In paragraph 3, The above first region is a battery module integrally connected to the above second region.

6. In paragraph 1, The first bus bar includes a first plate coupled to the tab portion; and a second plate coupled to the second bus bar and provided vertically at one edge of the first plate; A battery module in which the first plate is provided parallel to the tab portion and is joined to each other.

7. In paragraph 6, The second bus bar includes a connecting plate that can be in contact with one surface of the second plate; and a slit that is open to one side; A battery module in which the first plate is inserted into the slit and one surface of the second plate and one surface of the connecting plate are in contact.

8. In paragraph 1, A battery module in which the above first busbar is connected to the above second busbar through brazing welding.

9. In paragraph 1, A battery module wherein the first bus bar and the second bus bar include the same material.

10. In paragraph 1, A battery module further comprising an insulating part including an insulating material inside the module case.

11. A method for manufacturing a battery module comprising a main body for supplying or storing electric energy, a tab portion protruding from one side of the main body portion, a plurality of battery cells stacked along a first direction set in advance, a bus bar assembly for electrically connecting the plurality of battery cells, and a module case for accommodating the plurality of battery cells, A first joining step of joining the first busbar of the above busbar assembly to one side of the tab portion formed along the second direction, which is the protruding direction of the tab portion, and the third direction, which is perpendicular to the first direction and the second direction; and A method for manufacturing a battery module, comprising: a second joining step of connecting the first bus bar to a second bus bar extending along the second direction among the bus bar assembly.

12. In paragraph 11, A battery module manufacturing method further comprising a tab bending step of bending the tab so that the free end of the tab faces the main body.

13. In paragraph 12, The above tab bending step is a battery module manufacturing method in which the tab is bent twice.

14. In paragraph 11, The above first combining step A battery module manufacturing method comprising: arranging the first plate of the first busbar in parallel with the tab portion and joining the first busbar and the first plate by cold bonding.

15. In paragraph 14, The above first combining step A battery module manufacturing method for joining the first bus bar to the first plate through clinching bonding.

16. In paragraph 11, The above second combining step An insertion step of inserting the second plate of the first busbar into a slit open on one side of the second busbar; and A method for manufacturing a battery module, comprising: a contact step of bringing one surface of a second plate of the first bus bar into contact with one surface of a connecting plate of the second bus bar.

17. In paragraph 16, The above insertion step is A battery module manufacturing method in which the second bus bar moves along the third direction and the second plate is inserted into the slit.

18. In paragraph 16, The above second combining step A battery module manufacturing method for connecting the first bus bar to the second bus bar through brazing welding.

19. In paragraph 18, The above second combining step A battery module manufacturing method for welding the second plate and the second bus bar by supplying a filler metal to an area where the second plate and the second bus bar face each other along the third direction.

20. In paragraph 11, A battery module manufacturing method further comprising an insulation insertion step of inserting an insulation part including an insulation material inside the module case.

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