Battery cell, battery cell manufacturing device and method, electrolyte injection port sealing method for a housing

Abstract

The present disclosure relates to a battery cell, a battery cell manufacturing apparatus and a battery cell manufacturing method, a sealing method of an electrolyte injection port of a case, and a battery cell according to an embodiment of the present disclosure can include a case accommodating an electrode assembly, a cover plate coupled to the case and including an electrolyte injection port, and a sealing cover welded to the cover plate and sealing the electrolyte injection port, the sealing cover can include a first face exposed to an outside of the cover plate, a weld bead area protruding from the first face, and a scorch mark formed in the weld bead area. The present disclosure can provide a battery cell having removed residual electrolyte, contaminant substances, etc.

Description

Technical Field

[0001] This disclosure relates to a battery cell, a battery cell manufacturing apparatus, and a method. Background Technology

[0002] Batteries are not only used in small electronic devices such as mobile phones and laptops, but also widely used in large and medium-sized mechanical devices such as electric vehicles (EVs) and energy storage devices, with the advantages of being rechargeable and reusable.

[0003] Electrode assemblies, including positive and negative plates, can be housed in a pouch-shaped, square, or cylindrical casing selected according to the intended use, and an electrolyte can be injected to manufacture a battery cell.

[0004] Multiple battery cells can be connected together using busbars or similar devices to manufacture battery modules, battery packs, and energy storage systems (ESS).

[0005] The manufacturing process of a battery cell may include steps to remove residual electrolyte, contaminants, and other pollutants. This process can improve the quality of the battery cell. Summary of the Invention

[0006] Technical problems to be solved

[0007] According to one aspect of this disclosure, a battery cell with residual electrolyte, contaminants, etc., removed is provided.

[0008] In addition, according to one aspect of this disclosure, an apparatus and method are provided for manufacturing battery cells that have been free of residual electrolyte, pollutants, etc.

[0009] In addition, according to one aspect of this disclosure, a battery cell with improved quality is provided, and a battery cell manufacturing apparatus and method that can improve the quality of the battery cell are provided.

[0010] In addition, this disclosure can be widely applied to green technology fields such as solar power generation and wind power generation.

[0011] In addition, this disclosure can be applied to environmentally friendly devices that prevent climate change by suppressing air pollution and greenhouse gas emissions, such as eco-friendly electric vehicles and hybrid vehicles.

[0012] Technical solution

[0013] A battery cell according to an embodiment of the present disclosure may include: a housing for accommodating electrode assemblies; a cover plate connected to the housing and including an electrolyte injection port; and a sealing cap welded to the cover plate to seal the electrolyte injection port, the sealing cap including: a first surface exposed to the outside of the cover plate; a weld bead region protruding from the first surface; and a scorch mark formed in the weld bead region.

[0014] In one embodiment, the scorch mark may be formed at the outer edge of the weld bead region.

[0015] In one embodiment, in the weld bead region, the outer edge of the weld bead region may protrude from the first surface by a first height, the value of the first height being greater than 50 μm and less than 70 μm.

[0016] In one embodiment, the width of the weld bead region can be greater than 0.80 mm and less than 1 mm.

[0017] In one embodiment, the weld area may be formed around the sealing cap.

[0018] Furthermore, another aspect of this disclosure provides a battery cell manufacturing apparatus for manufacturing battery cells, the battery cell comprising: a housing housing an electrode assembly; a cover plate connected to the housing and including an electrolyte injection port; and a sealing cap welded to the cover plate to seal the electrolyte injection port, a first surface of the sealing cap exposing to the outside of the cover plate, the sealing cap including a weld bead region protruding from the first surface, wherein the battery cell manufacturing apparatus comprises: a welding section for welding the sealing cap and the cover plate while the electrolyte injection port is covered by the sealing cap, forming a pre-etched weld bead region on the first surface; and an etching section for irradiating the pre-etched weld bead region with a laser to form a scorch mark to form the weld bead region.

[0019] In one embodiment, the etching section may include: a laser oscillator for generating a laser source; and a scanner for providing the laser source to the sealing cover.

[0020] In one embodiment, the etching section may further include a focusing lens that focuses the laser light source provided by the scanner onto a focusing point located on the upper part of the cover plate.

[0021] In one embodiment, the focusing point can be separated from the cover plate by a distance of more than 1 mm and less than 2 mm.

[0022] In one embodiment, it may further include a foreign matter removal unit that supplies gas to the sealing cap.

[0023] In one embodiment, the foreign matter removal unit may supply nitrogen gas to the sealing cap.

[0024] Furthermore, another aspect of this disclosure provides a method for manufacturing a battery cell, the battery cell comprising: a housing housing an electrode assembly; a cover plate connected to the housing and including an electrolyte inlet; and a sealing cap welded to the cover plate to seal the electrolyte inlet, a first surface of the sealing cap exposing to the outside of the cover plate, the sealing cap including a weld bead region protruding from the first surface, wherein the method for manufacturing the battery cell comprises: a sealing step of welding the sealing cap and the cover plate while the electrolyte inlet is covered by the sealing cap to form a pre-etch weld bead region on the first surface; and an etching step performed after the sealing step of irradiating the pre-etch weld bead region with a laser to form the weld bead region and forming a scorch mark in the weld bead region.

[0025] In one embodiment, during the etching step, a laser can be irradiated onto the pre-etched weld bead region to make the height of the weld bead region reach the etching height, which can be more than 40% and less than 60% of the height of the pre-etched weld bead region.

[0026] In one embodiment, the etching step may include a focusing step of focusing a laser beam onto a focusing point located on the upper part of the cover plate, wherein the focusing point is spaced between 1 mm and 2 mm from the cover plate.

[0027] In one embodiment, during the etching step, a laser may be irradiated onto the outer edge of the pre-etched weld bead region.

[0028] In one embodiment, the focusing step may include: focusing the laser beam to a focusing point spaced at a distance of more than 1 mm and less than 2 mm from the upper part of the cover plate.

[0029] Furthermore, another aspect of this disclosure provides a method for sealing an electrolyte inlet of a housing, comprising: covering the inlet of the housing with a sealing cap; welding the sealing cap to the housing by forming a pre-etched weld bead region on the exposed external surface of the sealing cap; and removing at least a portion of the pre-etched weld bead region from the sealing cap by irradiating the pre-etched weld bead region with a laser, and forming a scorch mark in the weld bead region protruding from the sealing cap.

[0030] In one embodiment, laser conditions can be set such that a weld bead region with a height of more than 40% and less than 60% of the height of the pre-etched weld bead region is formed on the sealing cap, and laser is irradiated onto the pre-etched weld bead region according to the laser conditions.

[0031] In one embodiment, the laser conditions may be an average power of 300W, a frequency of 2500kHz or higher and 3000kHz or lower, an irradiation duration of 60ns, an overlap of 50%, and a peak power of 1.67kW or higher and 2.0kW or lower.

[0032] The effects of the invention

[0033] According to one aspect of this disclosure, a battery cell with residual electrolyte, contaminants, etc., removed can be provided.

[0034] In addition, according to one aspect of this disclosure, an apparatus and method for manufacturing battery cells that have had residual electrolyte, pollutants, etc. removed can be provided.

[0035] In addition, according to one aspect of this disclosure, a battery cell with improved quality can be provided, and a battery cell manufacturing apparatus and method that can improve the quality of the battery cell can be provided.

[0036] In addition, this disclosure can be widely applied to green technology fields such as solar power generation and wind power generation.

[0037] In addition, this disclosure can be applied to environmentally friendly devices that prevent climate change by suppressing air pollution and greenhouse gas emissions, such as eco-friendly electric vehicles and hybrid vehicles. Attached Figure Description

[0038] Figure 1 This is a partially exploded perspective view of a battery cell according to an embodiment of the present disclosure;

[0039] Figure 2 A schematic cross-sectional view of the cover plate according to this disclosure;

[0040] Figure 3 This is a schematic top view of a cover plate according to an embodiment of the present disclosure;

[0041] Figure 4 The illustration schematically shows the changes in the weld area of ​​a battery cell during the manufacturing process according to an embodiment of the present disclosure.

[0042] Figure 5 A battery cell manufacturing apparatus according to an embodiment of the present disclosure is illustrated schematically;

[0043] Figure 6 This illustration schematically shows the state in which the sealing cap and the cover plate are welded together by a welding part according to an embodiment of the present disclosure;

[0044] Figure 7This schematically illustrates the state in which a laser is irradiated onto a sealing cap through an etched portion according to an embodiment of the present disclosure;

[0045] Figure 8 This schematically illustrates the state in which a laser is irradiated onto a sealing cap through an etched portion according to an embodiment of the present disclosure;

[0046] Figure 9 This illustration schematically depicts a method for manufacturing a battery cell according to an embodiment of the present disclosure;

[0047] Figure 10 This illustration schematically shows a focusing point or focal point in a cell manufacturing method according to an embodiment of the present disclosure;

[0048] Figure 11 The illustration schematically depicts a method for manufacturing a battery cell according to an embodiment of the present disclosure.

[0049] Explanation of reference numerals in the attached figures

[0050] 110: Shell

[0051] 111: Capacity

[0052] 120: Cover plate

[0053] 121: Electrolyte injection port

[0054] 130: Sealing cap

[0055] 131: First Page

[0056] 132: Weld area

[0057] 210: Device frame

[0058] 220: Welding section

[0059] 230: Etching section

[0060] 240: Foreign Object Removal Department Detailed Implementation

[0061] To aid in understanding the description of the various embodiments of this disclosure, elements designated by the same reference numerals in the accompanying drawings are the same elements. Some structural elements in the drawings are shown in an exaggerated, omitted, or schematic manner, and the dimensions of each structural element do not perfectly reflect the actual dimensions.

[0062] In addition, for the sake of clarity of the subject matter of this disclosure, descriptions of elements and techniques well known in the prior art will be omitted. In the following, this disclosure will be described in detail with reference to the accompanying drawings.

[0063] Figure 1 This is a partially exploded perspective view of a battery cell according to an embodiment of the present disclosure.

[0064] In the following figures, the X-axis represents the width of the battery cell 100 or the length of the cover plate 120, the Y-axis represents the height of the battery cell 100 or the thickness of the cover plate 120, and the Z-axis represents the thickness of the battery cell 100 or the width of the cover plate 120. However, these directions are arbitrarily set for ease of understanding and can be changed.

[0065] Figure 1 This is a partially exploded perspective view of a battery cell 100 according to an embodiment of the present disclosure. Figure 2 This is a schematic cross-sectional view of the cover plate 120 according to the present disclosure.

[0066] like Figure 1 and Figure 2 As shown, a battery cell 100 according to an embodiment of this disclosure may include a housing 110, a cover plate 120, and a sealing cap 130. The housing 110 houses an electrode assembly 10. The cover plate 120 is connected to the housing 110 and includes an electrolyte inlet 121. The sealing cap 130 is welded to the cover plate 120, sealing the electrolyte inlet 121. A first surface 131 of the sealing cap 130 is exposed to the outside of the cover plate 120. In this case, the sealing cap 130 may include a weld bead region 132 protruding from the first surface 131 and a scorch mark M formed in the weld bead region 132.

[0067] For example, the first surface 131 can be the surface of the sealing cover 130 that is exposed to the outside.

[0068] In one embodiment, the battery cell 100 may be a prismatic battery cell 100. As an example, the casing 110 may be made of steel and may have a can shape. As an example, the casing 110 may be made of aluminum. The casing 110 may include a receiving space 111. At least one electrode assembly 10 may be received in the receiving space 111. The shapes of the casing 110 and the battery cell 100 are not particularly limited. Furthermore, the material of the casing 110 is not particularly limited, but may include steel or aluminum as described above.

[0069] The electrode assembly 10 may include at least one positive electrode plate, at least one negative electrode plate, and at least one separator that separates the at least one positive electrode plate and the at least one negative electrode plate from each other.

[0070] Positive electrode plates can be manufactured by coating positive electrode active materials onto positive electrode current collectors, and negative electrode plates can be manufactured by coating negative electrode active materials onto negative electrode current collectors.

[0071] The positive electrode current collector can be made of materials including aluminum, stainless steel, nickel, titanium, copper, or alloys thereof. The positive electrode active material can be in the form of a slurry formed by mixing and stirring a positive electrode active substance with a binder, conductive material, dispersant, etc. Here, conductive material, dispersant, and other commonly used additives can be mixed and stirred. Therefore, the coating of the positive electrode current collector according to some embodiments may include at least one of a positive electrode active substance, a binder, a conductive material, and a dispersant.

[0072] The negative electrode current collector can be made of materials including copper, gold, stainless steel, nickel, aluminum, titanium, or alloys thereof. The negative electrode active material can be in the form of a slurry formed by mixing and stirring a negative electrode active substance with a binder, conductive material, dispersant, etc. Here, conductive material, dispersant, and other commonly used additives can be mixed and stirred. Therefore, the coating of the negative electrode current collector according to some embodiments can include at least one of a negative electrode active substance, a binder, a conductive material, and a dispersant.

[0073] In addition, as an example, the positive current collector and the negative current collector can also be made of materials containing metals such as Co, Mn, and Li.

[0074] In one embodiment, the electrode assembly 10 may be disposed in the housing 110 in at least one of the following forms: stack or arrange, stack-fold, Z-fold, or coil. However, the method of forming the electrode assembly 10 is not limited to this disclosure.

[0075] At least one first electrode tab 11 can be connected to at least one positive electrode plate, and at least one second electrode tab 12 can be connected to at least one negative electrode plate. The first electrode tab 11 and the second electrode tab 12 can be made of conductive materials.

[0076] The cover 120 may cover the receiving space 111 and may be integrated with the housing 110. The cover 120 may include at least one venting region 124. The at least one venting region 124 may serve as a channel for exhaust gases present inside the housing 110, i.e., in the receiving space 111, to be discharged to the outside of the housing 110. However, the location, shape, number, and opening method of the venting region are not limited by this disclosure and may be appropriately selected and applied according to the specifications required by the battery cell 100.

[0077] The cover plate 120 may include a first terminal 122 and a second terminal 123. The first terminal 122 and the second terminal 123 may be made of a conductive material and may be exposed to the outside of the cover plate 120. Electrically insulating components may be provided at the connection areas of the first terminal 122 and the cover plate 120, and at the connection areas of the second terminal 123 and the cover plate 120. The insulating components may also be provided at the connection areas of the housing 110 and the cover plate 120. The insulating components may also be provided at other locations besides those described above, as needed. Although not shown in the figures, the first terminal 122 and the cover plate 120 may be insulated from each other by providing an electrically insulating material between them. Similarly, the second terminal 123 and the cover plate 120 may also be insulated from each other by providing an electrically insulating material between them. Additionally, an electrically insulating material may be provided between the housing 110 and the cover plate 120. Additional electrically insulating materials may also be provided at other locations besides those described above, as needed.

[0078] The first terminal 122 may include a first terminal connection area 122a, which may be electrically connected to the first electrode tab 11.

[0079] The second terminal 123 may include a second terminal connection area 123a, which may be electrically connected to the second electrode tab 12.

[0080] The cover plate 120 may include an electrolyte injection port 121, which is a hole penetrating the cover plate 120. Electrolyte can be injected into the receiving space 111 through the electrolyte injection port 121. After the electrolyte injection is completed, a sealing ball 125 can be provided at the electrolyte injection port 121 to seal it. The sealing ball 125 can seal the electrolyte injection port 121 to prevent electrolyte leakage to the outside of the housing 110. Alternatively, a portion of the sealing ball 125 can be melted to completely seal the electrolyte injection port 121.

[0081] The electrolyte inlet 121 can be covered by a sealing cap 130. The sealing cap 130 can cover the electrolyte inlet 121 after the sealing ball 125 has been used to seal the electrolyte inlet 121.

[0082] The sealing cap 130 may be configured such that the first surface 131 is exposed to the outside of the cover plate 120. The first surface 131 may be one of the multiple surfaces constituting the sealing cap 130 that faces the surface covering the electrolyte inlet 121.

[0083] The area or size of the sealing cap 130 can be greater than or equal to the area or size of the electrolyte inlet 121. As an example, the area or size of the sealing cap 130 can be larger than the area or size of the electrolyte inlet 121. In this case, the area or size can be the area or size on the thickness direction section (XZ plane) of the housing 110.

[0084] The sealing cap 130 can be made of a metal material. For example, the sealing cap 130 can be made of aluminum. For instance, the sealing cap 130 can be made of AL3003.

[0085] The sealing cap 130 can be welded to the cover plate 120. In one embodiment, the area including the edge of the sealing cap 130 can be welded to the cover plate 120. As an example, the sealing cap 130 can be welded to the cover plate 120 by laser welding. However, the type and method of welding are not limited to this disclosure.

[0086] The first surface 131 of the sealing cap 130 may be exposed to the outer surface of the cover plate 120. The sealing cap 130 and the cover plate 120 can be welded by irradiating the first surface 131 with a laser. Alternatively, in one embodiment, the sealing cap 130 may be configured to have a stepped shape in the thickness direction section (XY plane) of the cover plate 120. In this case, a portion of the sealing cap 130 may also be inserted into the electrolyte injection port 121. However, this is not limited to the present disclosure.

[0087] A weld bead region 132 may be formed on the first surface 131. The weld bead region 132 may protrude from the first surface 131 toward the height direction (Y direction) of the battery cell 100 or the thickness direction (Y direction) of the cover plate 120. As an example, the weld bead region 132 may include at least one of a back bead and a protrusion (humping beads).

[0088] The weld area 132 may include both the back weld and the protrusion, or it may include only one of them. In addition, the weld area 132 may be formed on at least one of the sealing cap 130 and the cover plate 120.

[0089] A protrusion can be a raised or protruding area that is created by excessive buildup of molten metal on the welding line during welding. At least a portion of such a protrusion can be removed later by etching.

[0090] At least one of such back weld and protrusion may also be present in the pre-etch weld area 132b. The pre-etch weld area 132b may be formed after the welding for joining the sealing cap 130 and the cover plate 120 is completed.

[0091] After the welding of the sealing cap 130 and the cover plate 120 is completed, at least a portion of the back weld bead and the protrusion can be removed by laser etching. Therefore, at least a portion of the weld bead region 132b before etching can be removed by laser etching to form the weld bead region 132. The weld bead region 132 is not completely removed but may remain on at least one of the sealing cap 130 and the cover plate 120. As an example, the weld bead region 132 may remain on the sealing cap 130.

[0092] Additionally, as an example, the weld bead region 132 may include a weld bead pattern formed by melting a portion of the cover plate 120 and a portion of the sealing cap 130. The weld bead pattern can be formed by solidifying the melted portion of the cover plate 120 and the sealing cap 130. As an example, the weld bead pattern may be formed at the end 132a of the weld bead region 132. The weld bead pattern may be curved or arc-shaped. In some embodiments, the weld bead pattern is located at the outermost upper edge of the weld bead region 132, for example, at the portion furthest from the cover plate 120 in the Y direction.

[0093] For visual inspection of weld patterns or weld areas 132, as an example, a predetermined amount of light can be shone onto the weld pattern or weld area 132 and the amount of reflected light can be detected and visually displayed on an image processing device (visual camera, visual device, etc.). The weld pattern or weld area 132 can also be inspected by the naked eye.

[0094] Figure 3 This is a schematic top view of a cover plate 120 according to an embodiment of the present disclosure. Figures 1 to 3 As shown, a scorch mark M can be formed in the weld bead region 132. As an example, the scorch mark M can be formed on the outer edge or end 132a of the weld bead region 132.

[0095] A scorch mark M can represent a trace or mark of scorching or burning. A scorch mark M can be formed by applying heat to the weld bead region 132 to burn or scorch the weld bead region 132. As an example, a scorch mark M can be formed by irradiating the weld bead region 132 or the end 132a of the weld bead region 132 with a laser beam.

[0096] In one embodiment, the sealing cap 130 may be circular or cylindrical. Therefore, in order to attach the sealing cap 130 to the cover plate 120, a welding device may perform welding around the periphery of the sealing cap 130. Thus, a weld bead region 132 may be formed around the periphery of the sealing cap 130.

[0097] In the thickness direction section or plane (XZ plane) of the battery cell 100, the sealing cap 130 can be circular, and the weld area 132 can be formed along at least one of the outline, edge, or periphery of the sealing cap 130. Therefore, the weld area 132 can also be formed approximately circular.

[0098] In the thickness direction section or plane (XZ plane) of the battery cell 100, a scorch mark M may be formed in the weld area 132. As an example, the scorch mark M may be formed at the end 132a of the weld area 132. In this case, the scorch mark M may also be formed along the periphery of the sealing cap 130 or the weld area 132.

[0099] On the other hand, a penetration region 120a can be formed on the cover plate 120 that is welded to the sealing cap 130. The penetration region 120a can be formed by melting the sealing cap 130 and the cover plate 120 with the aid of a welding heat source, and can be a region where the structure of the material constituting the cover plate 120 changes.

[0100] Figure 4 The illustration schematically shows the variation of the weld bead region 132 of the battery cell 100 during the manufacturing process according to an embodiment of the present disclosure. For example... Figure 4 As shown, after the sealing cap 130 and the cover plate 120 are welded together, a pre-etched weld bead region 132b can be formed on the first surface 131 of the sealing cap 130. The end 132c of the pre-etched weld bead region 132b can protrude a certain height from the first surface 131 of the sealing cap 130. No scorch marks M will form on the end 132c of the pre-etched weld bead region 132b.

[0101] The height of the end 132c of the weld bead region 132b before etching can be higher than the height of the end 132a of the weld bead region 132. In this case, the height can be the height in the thickness direction (Y direction) of the cover plate 120, and the weld bead region 132b before etching can be etched to form the weld bead region 132.

[0102] The pre-etch weld bead region 132b can be etched by irradiating the pre-etch weld bead region 132b with a laser beam. As a result, the height of the end 132c of the pre-etch weld bead region 132b is reduced to the height of the end 132a of the weld bead region 132.

[0103] In one embodiment, the end 132a of the weld bead region 132 may protrude from the first surface 131 by a first height H1. The first height may also be a straight-line distance in the Y-axis direction from the first surface 131 of the sealing cover 130 to the end 132a of the weld bead region 132. Here, the end 132a of the weld bead region 132 may include the highest region or highest point of the weld bead region 132 in the thickness direction section (XY plane) of the cover plate 120. Therefore, the first height H1 may also represent the distance from the first surface 131 to the highest point of the weld bead region 132.

[0104] In one embodiment, the value of the first height H1 can be greater than about 50 μm and less than about 70 μm. The first height H1 can be the lowest height of the weld bead region 132. That is, in the XY plane, it can be the height from the first surface 131 to the lowest point or lowest region of the weld bead region 132. The term "about" as used in this disclosure can be a value within ±10% of the indicated value. Additionally, embodiments of this disclosure can also be understood to exclude the term "about". For example, the first height H1 can be understood as a value greater than about 50 μm and less than about 70 μm, or as a value greater than 50 μm and less than 70 μm. This can also be applied in other embodiments with the same principle.

[0105] The first height H1 can be measured using a micrometer, laser distance meter, or similar device.

[0106] The weld bead region 132 has a first height H1, or the weld bead region 132 maintains at least a first height H1, thereby preventing deformation of the sealing cap 130 or cover plate 120. Simultaneously, defective areas in the weld bead region 132b before etching can be removed. Defective areas may include poorly welded areas (e.g., at least a portion of a hump weld bead), areas contaminated with or adhered to foreign matter such as electrolyte. Therefore, defective areas can be removed without reducing the quality of the battery cell 100.

[0107] In one embodiment, the width W1 of the weld bead region 132 can be 0.80 mm or more and 1 mm or less. The width W1 of the weld bead region 132 can be the width W1 of the weld bead region 132 in the thickness direction section (XY) of the cover plate 120. As an example, the width W1 of the weld bead region 132 can be the maximum width of the weld bead region 132. With this weld bead region 132, sufficient bonding area can be ensured between the sealing cap 130 and the cover plate 120.

[0108] Furthermore, another aspect of this disclosure provides a battery cell manufacturing apparatus 200 for manufacturing a battery cell 100, the battery cell 100 comprising: a housing 110 for housing an electrode assembly 10; a cover plate 120 connected to the housing 110 and including an electrolyte injection port 121; and a sealing cap 130 welded to the cover plate 120 to seal the electrolyte injection port 121, the first surface 131 of the sealing cap 130 being exposed to the outside of the cover plate 120, and the sealing cap 130 including a weld bead region 132 protruding from the first surface 131.

[0109] Figure 5 A schematic illustration shows a battery cell manufacturing apparatus 200 according to an embodiment of the present disclosure.

[0110] like Figures 1 to 5 As shown, a battery cell manufacturing apparatus 200 according to an embodiment of the present disclosure may include a welding section 220 and an etching section 230. The welding section 220 welds the sealing cap 130 and the cover plate 120 while the electrolyte injection port 121 is covered by the sealing cap 130, forming a pre-etched weld bead region 132b on the first surface 131. The etching section 230 irradiates the pre-etched weld bead region 132b with a laser to form a scorch mark M to form the weld bead region 132.

[0111] In this case, the pre-etched weld bead region 132b may have a height higher than the weld bead region 132. The weld bead region 132 may be a weld bead region 132 that protrudes from the first surface 131 after laser irradiation. At least a portion of the pre-etched weld bead region 132b can be removed by irradiating the pre-etched weld bead region 132b with a laser.

[0112] Additionally, the area remaining after laser irradiation of the pre-etched weld bead region 132b, protruding from the first surface 131, can be the weld bead region 132. A scorch mark M can be formed in the weld bead region 132.

[0113] In one embodiment, the welding portion 220 and the etching portion 230 may be provided on the device frame 210. Battery cells 100 may be supplied to the device frame 210. In some cases, battery cells 100 may also be supplied continuously. For this purpose, components such as conveyor belts and robotic arms for transferring battery cells 100 may also be provided on the device frame 210.

[0114] The battery cell 100 is transferred within the device frame 210, passing sequentially through the welding section 220 and the etching section 230. As an example, the battery cell 100 can be supplied to the welding section 220, where the sealing cap 130 and the cover plate 120 can be welded. In this case, a pre-etching weld bead region 132b can be formed on the first surface 131 of the sealing cap 130.

[0115] After the sealing cap 130 and the cover plate 120 are welded together, the battery cell 100 can be supplied to the etching section 230. The supply or transfer of the battery cell 100 can be carried out by a conveyor belt, robotic arm, etc.

[0116] The etching section 230 can irradiate the pre-etched weld bead region 132b with a laser to remove a portion of the pre-etched weld bead region 132b.

[0117] In one embodiment, the device frame 210 may also be equipped with a vision camera, a vision system, etc. The vision camera, vision system, etc. can acquire image information of the weld bead area 132, the weld bead area 132b before etching, the cover plate 120 and the sealing cover 130, and perform visual display.

[0118] Figure 6 The illustration schematically shows the state in which the sealing cap 130 and the cover plate 120 are welded together by the welding part 220 according to an embodiment of the present disclosure.

[0119] like Figure 6 As shown, the welding part 220 may include a welding head 221 and a welding drive component 222 connected to the welding head 221. When the electrolyte injection port 121 of the cover plate 120 is covered by the sealing cap 130, the welding head 221 welds the sealing cap 130 and the cover plate 120 to seal the electrolyte injection port 121.

[0120] The welding head 221 can be the welding head 221 of a laser welding machine. However, the type of welding is not necessarily limited to this disclosure.

[0121] The welding drive component 222 can move the welding head 221. Therefore, welding can be performed while moving it around the sealing cover 130.

[0122] In another embodiment, the welding drive component 222 and the welding head 221 can be connected to a controller. The controller may include at least one of a microcontroller or micro controller unit and a programmable logic controller (PLC). This allows welding to be performed automatically. However, welding can also be performed manually.

[0123] Figure 7 The illustration schematically shows the state in which the etched portion 230, according to an embodiment of the present disclosure, irradiates the sealing cover 130 with a laser.

[0124] like Figure 7 As shown, the etching section 230 according to an embodiment of the present disclosure may include: a laser oscillator 231 for generating a laser light source and a scanner 232 for providing the laser light source to the sealing cover 130.

[0125] The laser oscillator 231 can output a laser source or a laser beam. The laser oscillator 231 can output a laser source or laser beam that meets the following conditions: average power of 300W, frequency of 2500kHz or higher and 3000kHz or lower, duration of 60ns, overlap of 50%, and peak power of 1.67kW or higher and 2.0kW or lower. Therefore, it is possible to remove only the defective areas without removing the normal areas of the sealing cover 130 and the cover plate 120, or without causing a degradation in the quality of the sealing cover 130 and the cover plate 120. In this case, the peak power can be calculated using the following formula.

[0126] [Equation]

[0127] Peak power = Average power / (Frequency × Duration)

[0128] Peak power can represent the maximum instantaneous power of the laser source or laser beam. The laser source or laser beam generated by laser oscillator 231 can have predetermined pulse characteristics. The pulse has a width, and the peak power can be calculated from the width (peak duration) value and the repeatability (frequency) value of the width (peak duration). For example, peak power can be the ratio of pulse duration to pulse energy. Scanner 232 can provide or deflect the laser source or laser beam to the sealing cap 130. As an example, scanner 232 can provide or deflect the laser source or laser beam to the sealing cap 130 or the pre-etched weld bead region 132b.

[0129] In another embodiment, the battery cell manufacturing apparatus 200 may further include a vision system for acquiring image information of at least one of the sealing cap 130, the pre-etched weld bead region 132b, and the cover plate 120. Laser etching can be performed based on the image information acquired by the vision system.

[0130] exist Figure 7 In this context, the fourth height H4 can be the height of the pre-etched weld bead region 132b, and can be the straight-line distance from the first surface 131 of the sealing cap 130 to the end 132c of the pre-etched weld bead region 132b. In this case, the height of the pre-etched weld bead region 132b can be the height of the point with the highest height in the pre-etched weld bead region 132b.

[0131] The third height H3 can be the height of the weld bead region 132, which can be the straight-line distance from the first surface 131 of the sealing cap 130 to the end 132a of the weld bead region 132. The weld bead region 132 can be in a state where a portion of the weld bead region 132b before etching is removed by irradiating it with a laser. In this case, the height of the weld bead region 132 can be the height of the point with the highest height in the weld bead region 132.

[0132] The fourth height H4 can be higher than the third height H3. The etching section 230 can irradiate the pre-etched weld bead region 132b with a laser to reduce the height of the pre-etched weld bead region 132b to a fifth height H5. The fifth height H5 can be the height of the pre-etched weld bead region 132b removed by the laser.

[0133] The sum of the third altitude H3 and the fifth altitude H5 can be the fourth altitude H4.

[0134] The etching section 230 can reduce the height of the pre-etched weld bead region 132b by a fifth height H5 from the end 132c of the pre-etched weld bead region 132b. As an example, in the thickness direction section (XY plane) of the cover plate 120, the etching section 230 can remove the fifth height H5 from the pre-etched weld bead region 132b at the point with the highest height, the point with the lowest height, and the region connecting the point with the highest height and the point with the lowest height, among the multiple ends 132c of the pre-etched weld bead region 132b. In this case, if the pre-etched weld bead region 132b is tilted in the XY plane, there are multiple points or regions in the XY plane corresponding to the ends 132c of the pre-etched weld bead region 132b, therefore, multiple ends 132c of the pre-etched weld bead region 132b can exist.

[0135] In one embodiment, the third height H3 is the etching height, which can be the height of the weld bead region 132. The etching height can be the height of the weld bead region 132b after etching. The aforementioned first height can have the same value as the height of the weld bead region 132 and the third height H3.

[0136] In one embodiment, the value of the fifth height H5 can be more than 40% and less than 60% of the fourth height H4. That is, the fifth height H5 can have any value within the range of more than 40% and less than 60% of the fourth height H4. Here, when the weld bead region 132 and / or the pre-etch weld bead region 132b is formed at an angle or obliquely, the fifth height H5 can have multiple values.

[0137] That is, in the thickness direction section (XY plane) of the cover plate 120, when the end 132c of the pre-etched weld bead region 132b and the end 132a of the weld bead region 132 are connected by a straight line parallel to the Y axis, the fifth height H5 can have the same value as the height or length of the straight line.

[0138] When the weld bead region 132 and / or the pre-etch weld bead region 132b are formed at an angle or at an inclination, the fifth height H5 can be calculated by moving the end 132c of the pre-etch weld bead region 132b and the end 132a of the weld bead region 132 along the width direction (X direction) of the weld bead region 132. In this case, the fifth height H5 can have multiple values.

[0139] For example, the straight line connecting the end 132c of the pre-etched weld bead region 132b with the lowest height and the end 132a of the weld bead region 132 that overlaps with the end 132c of the pre-etched weld bead region 132b with the lowest height in the Y-axis direction can also be the fifth height H5. Similarly, the straight line connecting the end 132c of the pre-etched weld bead region 132b with the highest height and the end 132a of the weld bead region 132 that overlaps with the end 132c of the pre-etched weld bead region 132b with the highest height in the Y-axis direction can also be the fifth height H5. Under this principle, the straight line can be formed by moving along the width direction (X direction) of the weld bead region 132. Therefore, the fifth height H5 can have multiple values.

[0140] In this case, the multiple fifth heights H5 may have the same value as each other, or they may have different values. However, the values ​​of the multiple fifth heights H5 may be in the range of more than 40% and less than 60% of the fourth height H4.

[0141] In one embodiment, the fourth height H4 can be 120 μm, the fifth height H5 can be 60 μm, and the third height H3 can be 60 μm. This allows for the removal of poorly welded areas (such as hump welds) formed on the sealing cap 130. In this case, the poorly welded area can be formed on at least one of the sealing cap 130 and the cover plate 120.

[0142] In one embodiment, a vision system, sensors, etc., may be used to detect the state of the weld bead region 132b before etching removal, the height of the weld bead region 132, etc.

[0143] In another embodiment, the etching section 230 may also include a focusing lens 233, which focuses the laser light source provided by the scanner 232 onto a focusing point P located on the upper part of the cover plate 120.

[0144] The laser light source can illuminate the focusing point P. The position of the focusing point P can be adjusted by changing the specifications and position of the focusing lens 233.

[0145] In one embodiment, the focusing point P can be spaced from the cover plate 120 by a distance of 1 mm or more and less than 2 mm. As an example, in the thickness direction section (XY plane) of the cover plate 120, the focusing point P can be spaced from the cover plate 120 by a second height H2. The second height H2 can have the same value as the spacing distance between the focusing point P and the cover plate 120. In this case, the spacing distance or the second height H2 can have any value within the range of 1 mm or more and less than 2 mm.

[0146] A scorch mark M can be formed at the end 132a of the weld bead area 132 after laser etching. The quality of the weld bead area 132 can be inspected by a vision system or the like.

[0147] In one embodiment, the etching section 230 and the soldering section 220 can be connected to a controller. The controller may include at least one of a microcontroller or micro controller unit and a programmable logic controller (PLC). This allows etching to be performed automatically. However, the etching operation can also be performed manually.

[0148] Figure 8 The illustration schematically shows the state in which the etched portion 230, according to an embodiment of the present disclosure, irradiates the sealing cover 130 with a laser.

[0149] like Figure 8 As shown, the battery cell manufacturing apparatus 200 according to an embodiment of the present disclosure may further include a foreign matter removal unit 240 for supplying gas to the sealing cap 130.

[0150] In one embodiment, the foreign matter removal unit 240 may supply nitrogen gas to the sealing cap 130. Therefore, foreign matter (or waste, debris, etc.) generated during laser etching can be moved to the outside of the battery cell 100 by means of nitrogen gas. Nitrogen gas can help prevent oxidation of the welding area or weld bead area 132 of the sealing cap 130.

[0151] In some cases, a separate discharge box may also be installed to collect foreign objects. However, this is not necessarily limited to this disclosure.

[0152] Furthermore, another aspect of this disclosure provides a method for manufacturing a battery cell 100, the battery cell 100 comprising: a housing 110 for housing an electrode assembly 10; a cover plate 120 connected to the housing 110 and including an electrolyte injection port 121; and a sealing cap 130 welded to the cover plate 120 to seal the electrolyte injection port 121, the first surface 131 of the sealing cap 130 being exposed to the outside of the cover plate 120, and the sealing cap 130 including a weld bead region 132 protruding from the first surface 131.

[0153] Figure 9 The illustration schematically depicts a method for manufacturing a battery cell 100 according to an embodiment of the present disclosure.

[0154] like Figures 1 to 9 As shown, a method for manufacturing a battery cell 100 according to an embodiment of the present disclosure may include: a sealing step S110, in which the sealing cap 130 and the cover plate 120 are welded together while the electrolyte injection port 121 is covered by the sealing cap 130 to form a pre-etched weld bead region 132b on the first surface 131; and an etching step S120, performed after the sealing step S110, in which a laser is irradiated onto the pre-etched weld bead region 132b to form the weld bead region 132, and a scorch mark M is formed in the weld bead region 132.

[0155] For example, a method for manufacturing a battery cell 100 according to an embodiment of the present disclosure may include step S110, which involves welding a sealing cap 130 and a cover plate 120 as part of a sealing or sealing operation. For example, an electrolyte inlet 121 is covered by the sealing cap 130, and a pre-etched weld bead region 132b may be formed on the outwardly exposed surface 131 of the sealing cap 130. Subsequently, a laser may be irradiated onto the pre-etched weld bead region 132b to form a weld bead region 132, and as part of the etching step S120 performed after the sealing operation, a scorch mark M may be formed on the weld bead region 132.

[0156] In the sealing step S110, the sealing cap 130 and the cover plate 120 can be laser welded. As an example, the aforementioned battery cell manufacturing apparatus 200 can be used to perform the sealing step S110.

[0157] In the sealing step S110, the sealing cap 130 is fixed to the cover plate 120, and the electrolyte injection port 121 can be sealed by the sealing cap 130.

[0158] After sealing step S110 is completed, a weld bead region 132 may be formed in at least one region of the sealing cover 130 and the cover plate 120. As an example, after sealing step S110 is completed, a weld bead region 132 may be formed in the sealing cover 130.

[0159] The weld bead area 132 may include at least one of a back weld bead and a protrusion (hump weld bead). A protrusion may be a raised or protruding area caused by excessive buildup of molten metal on the welding line during welding. Protrusions may occur during high-speed welding or when excessive current is used, and may reduce weld quality.

[0160] The etching step S120 can remove at least a portion of at least one of the back weld bead and the protrusion (hump weld bead). Therefore, the welding quality can be improved. As an example, the etching step S120 can be performed using the aforementioned battery cell manufacturing apparatus 200.

[0161] The etching step S120 can be performed after the sealing step S110 is completed. The etching step S120 can be performed with the sealing cap 130 fixed to the cover plate 120. That is, the etching step S120 can be performed with the sealing cap 130 sealing the electrolyte injection port 121.

[0162] After the etching step S120 is completed, the pre-etched weld bead region 132b becomes the weld bead region 132, and a scorch mark M can be formed in the weld bead region 132.

[0163] In one embodiment, during etching step S120, a laser can be irradiated onto the pre-etched weld bead region 132b to bring the height of the weld bead region 132b to the etching height. The etching height can be a third height H3. The etching height or the third height H3 can be a value that is more than 40% and less than 60% of the height of the pre-etched weld bead region 132b. The height of the pre-etched weld bead region 132b can be a fourth height H4.

[0164] In one embodiment, during the etching step S120, a laser source or laser beam may be irradiated onto the pre-etched weld area 132b, which meets the following conditions: average power of 300W, frequency of 2500kHz or more and 3000kHz or less, duration of 60ns, overlap of 50%, and peak power of 1.67kW or more and 2.0kW or less.

[0165] Figure 10 The diagram schematically illustrates a focusing point P in a method for manufacturing a battery cell 100 according to an embodiment of the present disclosure. Figure 11 The illustration schematically depicts a method for manufacturing a battery cell 100 according to an embodiment of the present disclosure.

[0166] like Figure 10 and Figure 11As shown, in one embodiment of this disclosure, the etching step S120 may include a focusing step S121 of focusing the laser beam to a focusing point P located on the upper part of the cover plate 120. In this case, the focusing point P may be spaced from the cover plate 120 by a distance of more than 1 mm and less than 2 mm.

[0167] The focusing step S121 can be performed using a focusing lens 233. The focusing step S121 may also include a step of moving the focusing lens 233. The focusing point P can be set by adjusting the specifications of the focusing lens 233, such as its thickness, and its position.

[0168] According to the focusing step S121, the weld bead region 132b before etching can be etched such that the height of the etched weld bead region 132 is within a range of 40% to 60% of the height of the weld bead region 132b before etching. For example, the height of the etched weld bead region 132 can be approximately 50% of the height of the weld bead region 132b before etching. This can suppress quality degradation or breakage of the sealing cap 130 and the cover plate 120, and allows for easy removal of only the poorly welded areas.

[0169] In another embodiment, during etching step S120, a laser can be irradiated onto the end 132c or outer edge of the weld bead region 132b before etching, or the laser can be focused. Therefore, a scorch mark M can be formed at the end 132a of the etched weld bead region 132. The scorch mark M can be a mark or trace formed in the weld bead region 132 by laser etching.

[0170] The above description is merely an example of applying the principles of this disclosure. Other structures may be included or substituted for within the scope of this disclosure. Furthermore, this disclosure can be implemented by deleting or changing some constituent elements of the foregoing embodiments, or by combining various embodiments.

Claims

1. A single battery cell, comprising: Housing that houses the electrode assembly; A cover plate, connected to the housing, includes an electrolyte injection port; as well as A sealing cap, welded to the cover plate, seals the electrolyte injection port. The sealing cap includes: The first side is exposed to the outside of the cover plate; The weld area protrudes from the first surface; and Burn marks are formed in the weld area.

2. The battery cell according to claim 1, wherein: The scorch marks are formed at the outer edge of the weld area.

3. The battery cell according to claim 1 or 2, wherein: In the weld bead region, the outer edge of the weld bead region protrudes from the first surface by a first height. The value of the first height is greater than 50 μm and less than 70 μm.

4. The battery cell according to claim 1 or 2, wherein: The width of the weld bead area is greater than 0.80 mm and less than 1 mm.

5. The battery cell according to claim 1 or 2, wherein: The weld area is formed around the sealing cap.

6. A battery cell manufacturing apparatus for manufacturing battery cells, the battery cell comprising: Housing that houses the electrode assembly; A cover plate, connected to the housing, includes an electrolyte injection port; A sealing cap, welded to the cover plate, seals the electrolyte injection port. A first surface of the sealing cap protrudes from the outside of the cover plate. The sealing cap includes a weld bead area protruding from the first surface. The battery cell manufacturing apparatus includes: The welding section involves welding the sealing cap and the cover plate while the electrolyte injection port is covered by the sealing cap, forming a pre-etching weld area on the first surface. as well as In the etching section, a laser is irradiated onto the pre-etched weld bead area to form a scorch mark, thereby forming the weld bead area.

7. The battery cell manufacturing apparatus according to claim 6, wherein, The etched portion includes: Laser oscillator, used to generate a laser source; and The scanner provides the laser light source to the sealing cover.

8. The battery cell manufacturing apparatus according to claim 7, wherein, The etched portion further includes: A focusing lens focuses the laser light source provided by the scanner onto a focusing point located on the upper part of the cover plate.

9. The battery cell manufacturing apparatus according to claim 8, wherein: The focusing point is separated from the cover plate by a distance of more than 1 mm and less than 2 mm.

10. The battery cell manufacturing apparatus according to any one of claims 6 to 9, wherein, Also includes: The foreign matter removal unit supplies gas to the sealing cover.

11. The battery cell manufacturing apparatus according to claim 10, wherein: The foreign matter removal unit supplies nitrogen gas to the sealing cap.

12. A method for manufacturing a battery cell, used to manufacture a battery cell, the battery cell comprising: Housing that houses the electrode assembly; A cover plate, connected to the housing, includes an electrolyte injection port; A sealing cap, welded to the cover plate, seals the electrolyte injection port. A first surface of the sealing cap protrudes from the outside of the cover plate. The sealing cap includes a weld bead area protruding from the first surface. The battery cell manufacturing method includes: In the sealing step, the sealing cap and the cover plate are welded together while the electrolyte injection port is covered by the sealing cap to form a pre-etching weld area on the first surface. as well as The etching step, performed after the sealing step, involves irradiating the pre-etched weld area with a laser to form the weld area and creating scorch marks in the weld area.

13. The method for manufacturing a battery cell according to claim 12, wherein: In the etching step, a laser is irradiated onto the pre-etched weld bead area so that the height of the weld bead area reaches the etching height. The etching height is more than 40% and less than 60% of the height of the weld area before etching.

14. The method for manufacturing a battery cell according to claim 12 or 13, wherein: The etching step includes a focusing step of concentrating the laser beam to a focusing point located on the upper part of the cover plate. The focusing point is separated from the cover plate by a distance of more than 1 mm and less than 2 mm.

15. The method for manufacturing a battery cell according to claim 12 or 13, wherein: In the etching step, a laser is irradiated onto the outer edge of the pre-etched weld bead area.

16. The method for manufacturing a battery cell according to claim 14, wherein, The focusing step includes: The step of focusing the laser beam to a point that is spaced more than 1 mm and less than 2 mm away from the upper part of the cover plate.

17. A method for sealing the electrolyte injection port of a casing, comprising: The step of covering the electrolyte injection port of the housing with a sealing cap; The step of welding the sealing cap to the housing by forming a pre-etched weld bead area on the exposed external surface of the sealing cap; as well as The steps involve removing at least a portion of the pre-etched weld area from the sealing cap by irradiating the pre-etched weld area with a laser, and forming scorch marks in the weld area protruding from the sealing cap.

18. The sealing method for the electrolyte injection port of the casing according to claim 17, wherein: The laser conditions are set such that a weld bead region with a height of more than 40% and less than 60% of the height of the weld bead region before etching is formed on the sealing cover, and the laser is irradiated onto the weld bead region before etching according to the laser conditions.

19. The sealing method for the electrolyte injection port of the casing according to claim 18, wherein: The laser conditions are: average power 300W, frequency above 2500kHz and below 3000kHz, irradiation duration 60ns, overlap 50%, and peak power above 1.67kW and below 2.0kW.

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