Battery module and manufacturing method thereof

Abstract

The present disclosure relates to a battery module and a method of manufacturing the same, the battery module comprising: a plurality of battery cells each comprising an electrode tab; and a busbar in which a plurality of holes into which the electrode tabs are inserted are formed, the busbar being connected to the electrode tabs such that the plurality of battery cells are electrically connected to each other, the electrode tabs inserted into the holes being joined to the busbar by a weld, and the width of each of the holes in the direction in which the battery cells are stacked being 0.3 mm to 1.0 mm. According to the battery module and the manufacturing method thereof disclosed by the invention, the efficiency of a battery cell manufacturing project can be improved, and the battery is easier to recycle.

Description

Technical Field

[0001] The present disclosure relates to a battery module and a method for manufacturing the same. Background Art

[0002] Recently, various methods such as ultrasonic welding, laser welding, and mechanical (bolt / nut) joining have been used to electrically connect cells (batteries or secondary batteries) that require high reliability. However, in order to meet the increasing energy density requirements, laser welding is the most commonly used joining method.

[0003] This laser welding method generally uses overlapping welding of single or multiple electrode tabs and busbars. However, this method has the limitations of large deviation in tensile strength after welding and high possibility of poor welding such as weak welding depending on the pressurization conditions. In addition, for welding, the electrode tabs of various specifications in the unit module need to be bent and cut, resulting in increased processes and management costs.

[0004] Moreover, since the length of the electrode tabs of each battery cell in the module is different, the resistance of each battery cell is uneven, which is likely to have a negative impact on long-term durability. In particular, it is difficult to ensure stable welding quality (tensile strength, resistance, etc.) when welding dissimilar materials such as aluminum (Al) electrode tabs and bus bars.

[0005] In addition, there is also a limitation that the welding range is limited by the volume of the battery cell tabs. Summary of the invention

[0006] Technical issues

[0007] According to one aspect of the present disclosure, a technical problem to be solved is to improve the efficiency of a battery cell manufacturing process.

[0008] According to another aspect of the present disclosure, a technical problem to be solved is to provide a battery module with easier battery recycling and a method for manufacturing the same.

[0009] On the other hand, the battery module according to the present disclosure can be widely used in electric vehicles, battery charging stations, energy storage systems (ESS) and other green technology fields such as photovoltaic power generation and wind power generation using batteries. In addition, the battery module according to the present disclosure can be used for eco-friendly mobility, including electric vehicles and hybrid vehicles, which prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0010] Technical Solution

[0011] The battery module according to the present disclosure includes: a plurality of battery cells, each including an electrode tab; and a busbar, which is formed with a plurality of holes for the electrode tabs to be inserted respectively, and is connected to the electrode tabs so that the plurality of battery cells are electrically connected to each other. In addition, the electrode tabs inserted into the holes are combined with the busbar by a weld, and the width of each hole in the direction of stacking the battery cells can be 0.3 mm to 1.0 mm.

[0012] In one embodiment, the width of the hole may be 1.05 to 3.0 times the thickness of the electrode tab in the direction of stacking the battery cells.

[0013] In one embodiment, the thickness of the electrode tab may be greater than 0.2 mm.

[0014] In one embodiment, the length of the electrode tab in the direction in which the electrode tab protrudes from the battery cell may be 0.05 mm to 5.0 mm longer than the thickness of the busbar in the direction in which the electrode tab protrudes.

[0015] In one embodiment, the busbar may have a thickness of greater than 0.5 mm.

[0016] In one embodiment, the weld may be formed of a solder material different from the electrode tab.

[0017] In one embodiment, the solder may include the same material as the electrode tab.

[0018] In one embodiment, the electrode tab may include one or more of copper or aluminum.

[0019] In addition, the battery module according to the present disclosure may include: a plurality of battery cells, including electrode tabs; a plurality of holes for inserting the electrode tabs of the plurality of battery cells; a busbar, electrically connected to the electrode tabs inserted into the plurality of holes; and a weld, formed when the electrode tabs and the busbar are welded along the stacking direction of the plurality of battery cells to surround one end of the electrode tabs inserted into the plurality of holes and protruding to the outside. In addition, along the stacking direction of the plurality of battery cells, the width of any hole may be greater than the thickness of any electrode tab and less than the maximum length of any weld formed on any electrode tab.

[0020] In one embodiment, the weld may be formed by at least a portion of any electrode tab or a solder.

[0021] The manufacturing method of the battery module according to the present disclosure may include: a step of separating the electrode tabs of a plurality of battery cells connected to a first busbar from the first busbar; a step of inserting the separated electrode tabs into a plurality of holes included in a second busbar; and a step of forming a weld to join the electrode tabs to the second busbar. In addition, the width of each of the holes in the direction of stacking the battery cells may be 0.3 mm to 1.0 mm.

[0022] In one embodiment, the width of the hole may be 1.05 to 3.0 times the thickness of each electrode tab in the direction of stacking the battery cells.

[0023] In one embodiment, the length of the electrode tab in the direction in which the electrode tab protrudes from the battery cell may be 0.05 mm to 5.0 mm longer than the thickness of the busbar in the direction in which the electrode tab protrudes.

[0024] In one embodiment, in the step of bonding the electrode tab to the second bus bar, the method for manufacturing a battery module according to the present disclosure may irradiate laser while supplying another solder material different from the electrode tab.

[0025] In one embodiment, the weld may be formed using the solder as a base material.

[0026] In one embodiment, the solder may include the same material as the electrode tab.

[0027] In one embodiment, in the step of separating the electrode tab from the first bus bar, the method for manufacturing a battery module according to the present disclosure may cut the electrode tab.

[0028] Effects of the Invention

[0029] According to one embodiment of the present disclosure, the efficiency of a battery cell manufacturing process can be improved.

[0030] According to another embodiment of the present disclosure, a battery module and a method for manufacturing the same, which make it easier to recycle batteries, may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A diagram for explaining a battery module according to the present disclosure;

[0032] Figure 2 for Figure 1 A magnified image of

[0033] Figure 3 A diagram for explaining a bus bar of a battery module according to the present disclosure;

[0034] Figure 4 A diagram for explaining a state in which an electrode tab is connected to a bus bar in a battery module according to the present disclosure;

[0035] Figure 5 A diagram for explaining a weld of a battery module according to the present disclosure;

[0036] Figure 6 is a flow chart for illustrating a method for manufacturing a battery module according to the present disclosure;

[0037] Figure 7 and Figure 8 For illustration Figure 6 FIG. 100 of step S100;

[0038] Fig. 9 For illustration Figure 6 FIG. 100 of step S200;

[0039] Fig.10 and Fig.11 For illustration Figure 6 FIG. 10 is a diagram of step S300.

[0040] Description of Reference Numerals

[0041] 100: Battery module

[0042] 110: Battery cells

[0043] 120: Electrode ear

[0044] 150: Bus

[0045] 200: Brazing material

[0046] 300: Welding system DETAILED DESCRIPTION

[0047] The structural or functional descriptions of the embodiments disclosed in this specification or application are merely illustrative and are intended to illustrate embodiments of the technical ideas of the present disclosure. The embodiments of the technical ideas of the present disclosure may be implemented in a variety of ways in addition to the embodiments disclosed in this specification or application, and shall not be construed as limiting the technical ideas of the present disclosure to the embodiments described in the specification or application.

[0048] Figure 1 FIG. 1 is a diagram for explaining a battery module according to the present disclosure.

[0049] Reference Figure 1 The battery module 100 may include a plurality of battery cells 110 and electrode tabs 120 extending from the battery cells 110 . The electrode tabs 120 of each battery cell 110 may be electrically connected via a bus bar 150 .

[0050] A plurality of battery cells 110 may be stacked on top of each other. The electrode tabs 120 of the battery cells 110 may pass through the holes of the busbar 150 .

[0051] In an embodiment, the battery cell 110 may include a positive electrode, a negative electrode, and a separator disposed therebetween. In an embodiment, the positive electrode and the negative electrode may include a current collector and an active material layer disposed on the current collector, respectively. For example, the positive electrode may include a positive electrode current collector and a positive electrode active material layer, and the negative electrode may include a negative electrode current collector and a negative electrode active material layer.

[0052] Each battery cell 110 may include one or more electrode tabs 120 protruding in one direction.

[0053] In a specific example, the battery cell 110 may be a pouch-type battery cell. The pouch-type battery cell may be a battery cell in which an electrode assembly including a positive electrode (cathode), a negative electrode (anode) and a separator disposed therebetween is sealed in a pouch in a state of being immersed in an electrolyte (electrolyte). The bag may be a multilayer film structure in which a metal film such as an aluminum film is provided between an outer film and an inner film, but is not limited thereto. In a battery module 100 according to a specific example, the electrode tabs of each of the plurality of pouch-type battery cells 110 stacked in one direction are inserted into the respective holes of the busbar 150 and welded, and the plurality of pouch-type battery cells 110 may be electrically connected to each other in this way.

[0054] Figure 2 for Figure 1 Magnified image of .

[0055] Reference Figure 2By welding the electrode tab 120 and the bus bar 150 that pass through the hole formed in the bus bar 150 , a weld bead 170 may be formed on the bus bar 150 .

[0056] In one embodiment, the weld 170 may also originate from the electrode tab 120 .

[0057] In another embodiment, the weld 170 may be formed using a brazing filler metal supplied separately during welding as a base material.

[0058] In one embodiment, the weld 170 can be formed with the electrode tab 120 or the solder as the first parent material for welding and the busbar 150 as the second parent material for welding. The weld 170 can be derived from 70 to 99% by weight of the first parent material and the balance (1 to 30% by weight) of the second parent material, and advantageously, can be derived from 75 to 99% by weight of the first parent material and the balance (1 to 25% by weight) of the second parent material. That is, the dilution rate of the first parent material can be 85 to 99% and the dilution rate of the second parent material can be 1 to 15%, and advantageously, the dilution rate of the first parent material can be 89 to 99% and the dilution rate of the second parent material can be 1 to 11%. Here, a surface coating can be formed on the electrode tab as the first parent material (welding parent material) and / or the busbar 150 as the second parent material. That is, the electrode tab and / or the busbar 150 may include a surface coating, and in particular, the electrode tab that must ensure electrical / chemical stability to the electrolyte may include a surface coating. It is known that the surface coating for ensuring the electrochemical stability to the electrolyte may include any one of Ni, Sn, Si, Mg, Fe, Mn, Zn, Cr, Li, Ca or their alloys. In the case where the surface coating exists on the electrode tab and / or the busbar 150, it is obvious that the dilution rate of the surface coating itself can also be calculated by analyzing the weight % (wt %) of the weld containing the first base material, the second base material and the plating component. Regarding the composition of the weld metal (weld) of the entire welding process, all engineering factors can be quantified by Energy Dispersive Spectroscopy (EDS).

[0059] exist Figure 2 In, t b It may represent the thickness of the busbar 150, that is, the thickness of the busbar 150 in the direction in which the electrode tab 120 protrudes from the battery cell. In one embodiment, preferably, the busbar 150 has a thickness of 0.5 mm or more, and as an example, may have a thickness of 0.5 mm to 10 mm, 1 mm to 8 mm, or 1 mm to 6 mm, but is not necessarily limited thereto.

[0060] exist Figure 2 In, t cIt can represent the thickness of the electrode tab 120, that is, the thickness of the electrode tab 120 in the direction in which the battery cells are stacked. The electrode tab 120 can be configured as a through hole in a direction perpendicular to the surface of the busbar 150. The thickness of the electrode tab 120 is preferably greater than 0.2 mm, and more preferably, it can be 0.2 mm to 1.0 mm. When the electrode tab 120 has a thickness of greater than 0.2 mm, a weld 170 with better physical properties can be formed.

[0061] Figure 3 FIG. 1 is a diagram for explaining a bus bar of a battery module according to the present disclosure.

[0062] Reference Figure 3 The busbar 150 may be configured to include a plate 150a and a hole 150c formed on the plate. Here, the plate may include a plurality of holes 150c capable of accommodating each of the plurality of electrode tabs 120, and each hole 150c may have a shape and size corresponding to the cross-section of the electrode tab so that the end of the electrode tab can be inserted into the hole 150c.

[0063] In the present disclosure, one or more holes 150c are formed on the plate 150a, and a plurality of battery cells can be electrically connected by welding electrode tabs inserted into the holes 150c.

[0064] In an embodiment, one or more holes 150c may be formed on the plate 150a corresponding to the number of battery cells to be connected. Therefore, in order to electrically connect the battery cells, the battery cells may be electrically connected without changing the shape of the battery cells, regardless of the number of battery cells to be connected. The plate 150a constituting the bus bar 150 includes one or more holes 150c with preset intervals, and a plurality of battery cells may be electrically connected by welding electrode tabs inserted through the holes 150c. Here, an electrode tab may be inserted into each hole 150c and welded, so that a plurality of battery cells welded by the bus bar 150 may be electrically connected. In an embodiment, the hole 150c may be formed in a slit shape.

[0065] exist Figure 3 In, w s may denote a width of the hole 150c, that is, a width in a direction in which battery cells in the battery module are stacked on one another.

[0066] Figure 4 A diagram for explaining how an electrode tab is connected to a bus bar in a battery module according to the present disclosure.

[0067] Reference Figure 4The electrode tab 120 of the battery cell 110 may be inserted into the hole 150 c formed in the bus bar 150 . The electrode tab 120 may be inserted into the hole 150 c from one side of the bus bar 150 and protrude to the other side of the bus bar 150 .

[0068] In an embodiment, the width w of the hole 150c is s In one embodiment, the width w of the hole 150c is 0.3 mm to 1.0 mm. s The electrode tab 120 may have a thickness t c That is, after the electrode tab 120 of the battery cell 110 is inserted into the hole 150c formed in the busbar 150, the periphery of the hole 150c is welded to combine the electrode tab 120 and the busbar 150. Therefore, even if the width w of the hole 150c is s The thickness t of the electrode tab 120 c The larger difference can also easily combine the electrode tab 120 and the bus bar 150, thereby improving engineering efficiency. When combining the electrode tab 120 and the bus bar 150 by other means, in order to align and fix the electrode tab 120, the width w of the hole 150c is s The thickness t of the electrode tab 120 c The difference should be small, which may lead to a decrease in the assembly efficiency of the electrode tab 120 and the bus bar 150.

[0069] In one embodiment, when the electrode tab 120 and the bus bar 150 are bonded by irradiating the electrode tab 120 with laser, the width w of the hole 150 c is s The maximum thickness of the electrode tab is 120 mm. c In another embodiment, when the electrode tab 120 and the bus bar 150 are bonded by laser irradiation while supplying additional solder, the width w of the hole 150c is s The maximum thickness of the electrode tab is 120 mm. c 3 times.

[0070] That is, when welding the electrode tab 120 and the bus bar 150 while supplying another solder, even if the width w of the hole 150c is s The electrode tab is 120 mm thick. c The electrode tab 120 and the bus bar 150 can also be successfully combined with a current of 2.0 to 3.0 times.

[0071] In the embodiment, the length l of the electrode tab 120 is c The thickness t of the busbar 150 may be greater than b The length of the electrode tab 120 is 0.05 mm to 5.0 mm.c For example, it may be 0.5 mm to 15 mm, 1 mm to 12 mm, or 1 mm to 10 mm. That is, the electrode tab 120 of the battery cell 110 is inserted into the hole 150c formed in the busbar 150 and then welded around the hole 150c to combine the electrode tab 120 and the busbar 150. Therefore, the length l of the electrode tab 120 is c The thickness t of the busbar 150 b Even when the difference is smaller or larger than the range used in the past, the electrode tab 120 and the bus bar 150 can be easily combined, thereby improving engineering efficiency.

[0072] In one embodiment, when the electrode tab 120 and the bus bar 150 are bonded by irradiating the electrode tab 120 with laser, the length l of the electrode tab 120 is c The thickness t of the busbar 150 may be greater than b In another embodiment, when the electrode tab 120 and the bus bar 150 are bonded by laser irradiation while supplying additional solder, the length l of the electrode tab 120 is c The thickness t of the busbar 150 may be greater than b 0.05mm to 3.0mm long.

[0073] That is, when welding the electrode tab 120 and the bus bar 150 while supplying another solder, even if the length of the electrode tab 120 is l c The thickness t of the busbar 150 b The difference is 0.05 mm to 0.5 mm, that is, the difference is small and the length l of the electrode tab 120 c The thickness t of the busbar 150 b Even when the difference is 2.0 mm to 3.0 mm, that is, when the difference is relatively large, the electrode tab 120 and the bus bar 150 can still be successfully combined.

[0074] Figure 5 A diagram for explaining a weld of a battery module according to the present disclosure.

[0075] Reference Figure 5 The electrode tab 120 and the bus bar 150 may be connected to each other by a weld 170. In more detail, the weld 170 may connect the electrode tab 120 having the hole 150c therethrough to the bus bar 150. In an embodiment, the weld 170 may be formed by melting the electrode tab 120 or the brazing material by irradiation of a laser.

[0076] Here, Figure 5 The thickness t of the weld 170 at the busbar 150 can be shown. b Specifically, the busbar 150 has a thickness tb The weld cross section in the direction is the cross section parallel to the busbar with a thickness of 150 b The cross section cut by the imaginary plane in the thickness direction (the imaginary plane in the plane in the thickness direction) can further refer to the welding cross section cut to minimize the area of ​​the weld 170. As a substantial example, Figure 2 In the example shown, the imaginary plane p of the cross-section forming the weld 170 may be parallel to the thickness t of the busbar 150. b Direction and parallel to the thickness of the electrode tab t c The cross section of the weld 170 may refer to a cross section taken through the above-mentioned imaginary plane p.

[0077] In an embodiment, the weld may have a width W and a height H that satisfy the following Formulas 1 and 2.

[0078] <Formula 1>

[0079] 0 <W≤9T

[0080] In Formula 1, W is the thickness t of the busbar 150 b The width of the weld 170 based on the weld cross section in the direction, t c is the thickness of the electrode tab 120 .

[0081] <Formula 2>

[0082] 0 <H≤4.5t c

[0083] In Formula 2, H is the thickness t of the busbar 150 b The height of the weld cross section in the direction is 170°, t c is the thickness of the electrode tab 120 .

[0084] Among them, t c The unit can be mm.

[0085] In one embodiment, in the case of using an additional solder to form the weld 170 , the upper limits of the width W and the height H may be increased compared to the case of directly welding the electrode tab 120 .

[0086] Advantageously, in order to ensure stable welding quality, the weld width W can be 2t c Up to 8t c , more advantageously, can be 3t c Up to 7t c , the height H can be 0.5t c Up to 3t c , more advantageously, can be 0.5t c Up to 2t c. When the width and height of the weld 170 are satisfied, the weld has high tensile strength and low contact resistance, thereby exhibiting excellent welding characteristics. Furthermore, when the weld 170 satisfies such width and height, even if specific welding conditions, such as the heat gradient state caused during welding or the laser irradiation method during welding, change, it is possible to ensure a certain welding quality (improved welding strength, excellent electrical characteristics of the welded portion, etc.) stably and reproducibly.

[0087] The width and height of the weld 170 may directly affect the cross-sectional area of ​​the weld 170. Therefore, in another embodiment, the electrode tab 120 inserted into the hole 150c is combined with the busbar 150 through the weld 170, and the weld 170 may satisfy the following formula 3.

[0088] <Formula 3>

[0089] 0 <A≤40.5t c 2

[0090] In Formula 3, A is the thickness t of the busbar 150 b The cross-sectional area of ​​the weld in the direction is the cross-sectional area of ​​the weld 170 as the reference, t c is the thickness of the electrode tab.

[0091] In one embodiment, when an additional solder is used to form the weld 170 , the upper limit of the cross-sectional area A may be increased compared to the case of directly welding the electrode tab 120 .

[0092] The weld 170 may satisfy the above-mentioned Formula 1 and Formula 2 as well as Formula 3. Independently of this, the weld 170 may satisfy Formula 1, Formula 2, or Formula 1 and Formula 2 as well as Formula 3.

[0093] The width W of the weld 170 may refer to the thickness t of the busbar 150. b In the weld cross section in the direction, the thickness t of the electrode tab of the weld 170 that will contact the busbar 150 c The distance between the two left and right boundary points p1 and p2 is taken as the distance between the two ends in the direction. Figure 5 The example shown is the case where the two boundary points p1 and p2 on the left and right are at the same height. Figure 5 The width of the weld is shown in FIG. 1 . When the two boundary points p1 and p2 are not located at the same height, the shortest distance between the two boundary points can be defined as the width of the weld. c The direction is defined as the width direction of the weld 170 cross section.

[0094] The height H of the weld 170 may be equal to the thickness t b The distance (shortest distance) between the imaginary line connecting the left and right boundary points p1 and p2 and the highest point of the weld 170 in the weld cross section in the direction. In this case, Figure 5 The example shown is the case where the two boundary points p1 and p2 on the left and right are at the same height. Figure 5 Only the width of the weld is shown, and the height of the weld 170 can be defined as the shortest distance between an imaginary line connecting the two left and right boundary points and the highest point of the weld 170 .

[0095] In a specific example, weld 170 may also satisfy equation 4.

[0096] <Formula 4>

[0097] 0.4t c ≤D≤4t c

[0098] In Formula 4, D is the thickness t of the busbar 150. b The penetration depth of the weld 170 into the hole based on the cross section of the weld 170 in the direction, t c is the thickness of the electrode tab.

[0099] In one embodiment, in the case of using an additional solder to form the weld 170 , the upper limit of the penetration depth D may be increased compared to the case of directly welding the electrode tab 120 .

[0100] In one embodiment, the thickness t of the busbar 150 is b In the cross section of the weld 170 in the direction, the weld 170 may be symmetrical or asymmetrical with respect to the center line CL of the hole 150c. Here, as the electrode tab 120 is inserted into the hole 150c, the center line of the hole 150c may be the same as the center line of the electrode tab 120 inserted into the hole 150c. Figure 5 , left-right asymmetry may refer to setting the shortest distances between the left and right boundary points p1 and p2 and the center line of the hole to L1 and L2, and when L1 is different from L2, setting the longer length to L2, and the ratio of L1 to L2 is 1:1 to 1:3.

[0101] In one embodiment, when the weld 170 is formed using an additional solder, the left-right symmetry of the weld 170 can be improved compared to the case where the electrode tab 120 is directly welded.

[0102] Reference Figure 5, the battery module according to the present disclosure may include: a plurality of battery cells 110 including electrode tabs 120; a plurality of holes 150c for inserting the electrode tabs 120 of the plurality of battery cells 110; a bus bar 150 electrically connected to the electrode tabs 120 inserted into the plurality of holes 150c; and a weld 170 formed to surround one end of the electrode tabs 120 inserted into the plurality of holes 150c and protruding to the outside when the electrode tabs 120 and the bus bar 150 are welded along the stacking direction of the plurality of battery cells 110. Moreover, along the stacking direction of the plurality of battery cells 110, the width of any hole 150c may be greater than the thickness of any electrode tab 120 and less than the maximum length of any weld 170 formed on any electrode tab 120.

[0103] Furthermore, the plurality of welds 170 may be formed by at least a portion of any one of the electrode tabs 120 or the solder.

[0104] Figure 6 The flowchart is used to illustrate the manufacturing method of the battery module according to the present disclosure.

[0105] Reference Figure 6 , the manufacturing method of the battery module according to the present disclosure may include a step S100 of separating the electrode tabs of multiple battery cells from the first bus. Step S100 may be a process of disassembling the battery module in order to recycle the previously used battery module. That is, the first bus may be a bus included in the previously used battery module. For example, the previously used battery module may be in a form in which the electrode tabs of multiple battery cells are respectively inserted into multiple holes formed in the bus as in one embodiment of the present disclosure, and the electrode tabs are combined with the bus through welds. Alternatively, the previously used battery module may be in a form in which multiple electrode tabs are bent after passing through a slit formed in the bus, and the bent electrode tabs are joined to the bus.

[0106] Next, the manufacturing method of the battery module according to the present disclosure may include a step (S200) of inserting the electrode tabs into the plurality of holes formed in the second busbar. Here, the second busbar may be a busbar included in the battery module to be newly assembled. The second busbar may be Figures 1 to 5 The bus described in .

[0107] Next, the manufacturing method of the battery module according to the present disclosure may include a step of bonding the electrode tab to the second busbar (S300). The bonding of the electrode tab to the second busbar may be formed by a weld. The weld may be formed by melting the electrode tab or another solder. The weld may be formed as follows: Figure 5 Said instructions.

[0108] In one embodiment, the manufacturing method of the battery module according to the present disclosure may be a method for recycling a previously used battery module. That is, the battery module manufactured according to the manufacturing method of the battery module according to the present disclosure may be in a form in which the battery cells are separated from the previously used battery module and then assembled into a new busbar.

[0109] Figure 7 and Figure 8 For illustration Figure 6 FIG. 100 of step S100.

[0110] Reference Figure 7 In one embodiment, the first busbar 1150 may be a busbar included in a previously used battery module. In one embodiment, the previously used battery module may be a form in which a plurality of electrode tabs 120 are bent after passing through a slit formed in the busbar, and the bent electrode tabs 120 are engaged with the first busbar 1150. The electrode tab 120 may be bent and located on the first busbar 1150, and may be welded at a position on the first busbar 1150. In this way, when the electrode tab 120 and the first busbar 1150 are combined, the required length of the electrode tab 120 is longer.

[0111] Reference Figure 8 , the electrode tab 120 connected to the first bus bar 1150 can be separated from the first bus bar 1150. In one embodiment, Figure 8 It can be a process of disassembling a previously used battery module. In an embodiment, the separation of the electrode tab 120 can be performed by cutting the electrode tab. The cut electrode tab 120 has a shorter length, and the length of the electrode tab 120 may be uneven. Therefore, in the case of recycling the battery cells in the previously used battery module, it is somewhat difficult to recycle due to the restrictions of the electrode tab, but the battery module and the manufacturing method thereof according to the present disclosure involve a new solution for eliminating such restrictions. Figures 9 to 11 This is explained in more detail.

[0112] Fig. 9 For illustration Figure 6 FIG. 10 is a diagram of step S200.

[0113] Reference Fig. 9 , the electrode tab 120 of the battery cell 110 may be inserted into the hole 150 c formed in the bus bar 150 . The electrode tab 120 may be inserted into the hole 150 c from one side of the bus bar 150 and protrude to the other side of the bus bar 150 .

[0114] The lengths of the electrode tabs 120 in the protruding direction may be uneven and different from each other. Figure 4If the electrode tab 120 is within the range shown, the electrode tab 120 can be stably coupled to the busbar 150. That is, if the length of the electrode tab 120 is 0.05 mm to 5.0 mm longer than the thickness of the busbar 150, the electrode tab 120 and the busbar 150 can be easily coupled, thereby improving engineering efficiency.

[0115] Moreover, if combined Figure 4 The description above shows that the width of the hole 150c formed in the busbar 150 can be 0.3 mm to 1.0 mm, and the width of the hole 150c can be the thickness t of the electrode tab 120. c The width of the hole 150c is 1.05 to 3.0 times, preferably 1.1 to 2.9 times. That is, even if the width of the hole 150c is greatly different from the thickness of the electrode tab 120, the electrode tab 120 and the bus bar 150 can be easily combined, thereby improving engineering efficiency.

[0116] Fig.10 and Fig.11 For illustration Figure 6 FIG. 10 is a diagram of step S300.

[0117] Reference Fig.10 and Fig.11 A weld may be formed by irradiating a laser to the electrode tab 120 or another solder 200 , and the electrode tab 120 and the bus bar 150 may be bonded by the weld.

[0118] Fig.10 An embodiment of irradiating laser to the electrode tab 120 by the welding system 300 is shown.

[0119] The laser L irradiated by the welding system 300 can be irradiated at an angle relative to the center axis of the length direction d of the electrode tab 120 inserted into the hole 150c and protruding. As a result, the possibility of an accident caused by the laser L directly irradiating the battery cell due to an error during welding when irradiating perpendicularly to the end face of the electrode tab 120 can be minimized, and by irradiating the laser L at an angle, the welding process of the end face of the electrode tab 120 can be confirmed with the naked eye, thereby improving the quality and production speed of the battery module.

[0120] exist Fig.10 In the case of the embodiment of the present invention, the base material of the weld formed may be the electrode tab 120. That is, the electrode tab 120 may be cooled after being melted to form the weld. In one embodiment, the weld may be formed with the electrode tab 120 as the first base material and the bus bar 150 as the second base material.

[0121] and Fig.10 different, Fig.11Another embodiment of irradiating the laser L to the solder 200 supplied separately by the soldering system 300 is shown. The solder 200 may be arranged on the bus bar 150, or the solder 200 may be supplied by another device. In one embodiment, the solder 200 may be supplied by a supply part included in the soldering system 300. In one embodiment, the solder 200 may be provided in the form of a wire.

[0122] The solder 200 may be melted by irradiating the laser L to the solder 200 through the welding system 300. The melted solder may be re-cooled to bond the electrode tab 120 and the bus bar 150.

[0123] In an embodiment, the solder 200 may include the same material as the electrode tab 120. In the case where the solder 200 and the electrode tab 120 are made of the same material, a weld formed by the solder 200 and the electrode tab 120 may be easily joined.

[0124] Moreover, in one embodiment, the electrode tab 120 and the solder 200 may include a material different from that of the busbar 150. For example, the electrode tab 120 may include aluminum (Al), and the busbar 150 may include copper (Cu). Alternatively, the electrode tab 120 may include copper (Cu), and the busbar 150 may include aluminum (Al). In another embodiment, the electrode tab 120 and the solder 200 may also include the same material as that of the busbar 150.

[0125] like Fig.11 As shown, in the case of using the additional solder 200 , the electrode tab 120 and the bus bar 150 can be successfully bonded even if the width of the hole 150 c is greater than the thickness of the electrode tab 120 .

[0126] Moreover, if Fig.11 When another solder material 200 is used, the difference between the length of the electrode tab 120 and the thickness of the busbar 150 is small and the length l of the electrode tab 120 is c The thickness t of the busbar 150 b In the case of large differences, the electrode tab 120 and the bus bar 150 can be successfully combined.

[0127] The present disclosure can be implemented in various ways, so its scope of rights is not limited to the above-mentioned embodiments. Therefore, as long as the modified embodiments include the constituent elements of the claims of the present disclosure, they should be considered to fall within the scope of rights of the present disclosure.

Claims

1. A battery module, comprising: A plurality of battery cells, each including an electrode tab; as well as A bus bar is formed with a plurality of holes for the electrode tabs to be inserted respectively, and is connected to the electrode tabs so that the plurality of battery cells are electrically connected to each other. The electrode tab inserted into the hole is connected to the busbar by welding. The width of each of the holes in the direction of stacking the battery cells is 0.3 mm to 1.0 mm.

2. The battery module according to claim 1, wherein: The width of the hole is 1.05 to 3.0 times the thickness of the electrode tab in the direction of stacking the battery cells.

3. The battery module according to claim 1 or 2, wherein: The thickness of the electrode tab is greater than 0.2 mm.

4. The battery module according to claim 1, wherein: The length of the electrode tab in the direction in which the electrode tab protrudes from the battery cell is 0.05 mm to 5.0 mm longer than the thickness of the busbar in the direction in which the electrode tab protrudes.

5. The battery module according to claim 1 or 4, wherein: The busbar has a thickness of 0.5 mm or more.

6. The battery module according to claim 1, wherein: The weld seam is formed by a solder material different from the electrode tab.

7. The battery module according to claim 6, wherein: The solder includes the same material as the electrode tab.

8. The battery module according to claim 1, wherein: The electrode tab includes at least one of copper and aluminum.

9. A battery module, comprising: A plurality of battery cells including electrode tabs; A bus bar, comprising a plurality of holes for inserting the electrode tabs of the plurality of battery cells, and electrically connected to the electrode tabs respectively inserted into the plurality of holes; as well as The weld is formed when the electrode tabs and the busbar are welded along the stacking direction of the plurality of battery cells so as to surround one end of each of the electrode tabs respectively inserted into the plurality of holes and protruding to the outside, Wherein, along the stacking direction of the plurality of battery cells, the width of any hole is greater than the thickness of any electrode tab and less than the maximum length of any weld formed on any electrode tab.

10. The battery module according to claim 9, wherein: The weld is formed by at least a portion of any one of the electrode tabs or a solder.

11. A method for manufacturing a battery module, comprising: The step of separating the electrode tabs of a plurality of battery cells connected to a first busbar from the first busbar; The step of inserting the separated electrode tabs into a plurality of holes included in the second bus bar respectively; as well as forming a weld to join the electrode tab to the second busbar, Wherein, the width of each of the holes in the direction of stacking the battery cells is 0.3 mm to 1.0 mm.

12. The method for manufacturing a battery module according to claim 11, wherein: The width of the hole is 1.05 to 3.0 times the thickness of each electrode tab in the direction of stacking the battery cells.

13. The method for manufacturing a battery module according to claim 11, wherein: The length of the electrode tab in the direction in which the electrode tab protrudes from the battery cell is 0.05 mm to 5.0 mm longer than the thickness of the bus bar in the direction in which the electrode tab protrudes.

14. The method for manufacturing a battery module according to claim 11, wherein: The step of joining the electrode tab to the second bus bar is performed by irradiating laser light while supplying a solder different from the electrode tab.

15. The method for manufacturing a battery module according to any one of claims 11 to 14, wherein: The step of separating the electrode tab from the first bus bar is performed by cutting the electrode tab.

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