Laser welding apparatus and method using horizontal irradiation laser, and secondary battery

Abstract

Disclosed are a laser welding apparatus, a laser welding method, and a secondary battery. The laser welding apparatus includes: a chamber configured to allow a laser beam laterally irradiated to a welding region between members to be welded to pass therethrough; and a vortex forming portion configured to connect a welding region between the members to be welded and the chamber, supply gas to the welding region, and form and discharge vortex gas.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0159610 filed in the Korean Intellectual Property Office on November 16, 2023, the disclosure of which is incorporated herein in its entirety by reference. Technical Field

[0002] Aspects of embodiments of the present disclosure are directed to a welding apparatus and a secondary battery manufactured by the welding apparatus. Background Art

[0003] Unlike primary batteries that are not designed to be recharged, secondary batteries are designed to be repeatedly discharged and recharged. Typically, a secondary battery includes an electrode assembly including a positive electrode and a negative electrode, a case that accommodates the electrode assembly, an electrode terminal connected to the electrode assembly, an exhaust port for exhausting gas generated inside the case, etc.

[0004] In secondary batteries, laser welding can be used to join its components. When a high-energy laser beam is used to irradiate the base material (the component to be welded) during laser welding, heat is generated and the generated heat is transferred to adjacent components. In this case, smoke and splashes are generated due to the large energy. The generated smoke and splashes interfere with the transmission of the laser beam by falling on the component to be welded and flow into the secondary battery.

[0005] The above information disclosed in this Background section is for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute related (or prior) art. Summary of the invention

[0006] Aspects of embodiments of the present disclosure relate to an improved laser welding apparatus and method that utilizes lateral (e.g., horizontal) laser irradiation to perform welding of products such as secondary batteries to prevent or substantially block the flow of smoke and spatter into the product, and uses a gas supply structure for welding to increase the airflow of the exhaust to perfectly discharge the smoke and spatter.

[0007] Furthermore, aspects of embodiments of the present disclosure relate to a secondary battery manufactured using the above laser welding apparatus or method.

[0008] According to some embodiments of the present disclosure, a laser welding device is provided, which includes: a chamber, which is configured to allow a laser beam that is laterally irradiated to a welding area between components to be welded to pass through it; and a vortex forming part, which is configured to connect the welding area between the components to be welded and the chamber, supply gas to the welding area, and form and discharge vortex gas.

[0009] In some embodiments, the vortex forming portion includes: a gas layer forming portion configured to supply gas to the welding region; and a vortex gas outlet through which the vortex gas formed inside the vortex forming portion is emitted.

[0010] In some embodiments, the chamber includes a release port configured to release the vortex gas formed in the vortex forming portion out of the chamber.

[0011] In some embodiments, the laser welding apparatus further includes a fan configured to draw the swirling gas from the release port.

[0012] In some embodiments, the chamber includes a transparent glass shield configured to allow transmission of a laser beam irradiated laterally from the outside.

[0013] In some embodiments, the chamber further comprises a glass-shielded exhaust port communicating with the outside.

[0014] In some embodiments, the chamber includes at least one exhaust port communicating with the exterior.

[0015] In some embodiments, the vortex forming portion includes a tapered tube having a diameter that gradually decreases from the chamber to the welding region.

[0016] In some embodiments, the vortex forming portion includes: a gas injection port configured to inject gas; and a gas supply channel configured to supply the gas injected through the gas injection port to the welding area, the gas supply channel including: an inflow end configured to introduce the gas injected through the gas injection port; a closed end configured to block the advance of the gas introduced into the inflow end; and an injection port positioned at a certain distance from the closed end and open toward the vortex forming portion, and configured to inject gas in a circumferential direction of the vortex forming portion to form a vortex gas by causing the gas injected in the circumferential direction of the vortex forming portion to rotate along the inner wall of the vortex forming portion.

[0017] In some embodiments, the injection port is configured to allow injection of gas within a range of an angle formed by an inner wall of the vortex forming portion and a straight line connecting a center of the vortex forming portion and a center of the gas supply channel.

[0018] In some embodiments, the direction of injection from the injection port is 90° with respect to a straight line connecting a center of the vortex forming portion and a center of the gas supply channel.

[0019] In some embodiments, the injection port has a diameter that is smaller than a diameter of the gas supply channel.

[0020] In some embodiments, the gas supply channel includes a plurality of gas supply channels; and the vortex forming portion further includes a manifold configured to distribute the gas injected through the gas injection port to corresponding inflow ends of the plurality of gas supply channels.

[0021] In some embodiments, the manifold includes a plurality of manifolds; and the vortex forming portion further includes a branch pipe configured to branch the gas injected into the plurality of manifolds through the gas injection port.

[0022] In some embodiments, the vortex gas injected from the injection port of the gas supply channel and formed in the vortex forming portion enters the chamber.

[0023] In some embodiments, the components to be welded are a cap plate and a current collector of a secondary battery.

[0024] According to some embodiments of the present disclosure, a laser welding method is provided, the method comprising the following steps: irradiating a laser beam laterally to a welding area between components to be welded; supplying gas to the welding area; and forming a vortex gas by the gas supplied to the welding area to discharge the vortex gas together with smoke and spatter generated during welding.

[0025] In some embodiments, in the step of forming vortex gas: vortex gas is formed by spraying gas supplied to the welding area circumferentially along the inner wall of the first end of the cylindrical hollow member; and the formed vortex gas is discharged from the second end of the cylindrical hollow member while rotating along the inner wall of the cylindrical hollow member.

[0026] In some embodiments, the laser welding method further includes collecting the vortex gas exhausted in the step of forming the vortex gas in the chamber, and releasing the collected vortex gas out of the chamber.

[0027] According to some embodiments of the present disclosure, a secondary battery manufactured using the above laser welding method is provided.

[0028] According to some aspects of the present disclosure, a secondary battery manufactured using the above laser welding apparatus or laser welding method is provided.

[0029] As is apparent from the above description, according to some embodiments of the present disclosure, even if the welding equipment moves during welding, the lateral (e.g., horizontal) irradiation of the laser can prevent or substantially block the spatter from flowing into the product. The suction mechanism in the existing welding equipment of the prior art has the disadvantage that it cannot completely collect the spatter and smoke that fall into the product. However, the present disclosure can significantly reduce the occurrence of product defects because the spatter and smoke can be completely released through the improved structure. Therefore, the yield and operation rate can be ensured by minimizing or reducing the interference of smoke and spatter on the laser beam and reducing the occurrence of defects caused by contamination. However, the aspects and features of the present disclosure are not limited to the aspects and features described above, and those skilled in the art will clearly understand other aspects and features not mentioned through the detailed description described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings attached to this specification illustrate embodiments of the present disclosure, and together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to the accompanying drawings:

[0031] Figure 1 is a cross-sectional view of a cylindrical secondary battery according to some embodiments of the present disclosure;

[0032] Figure 2A is a top perspective view of a prismatic secondary battery according to some embodiments of the present disclosure;

[0033] Figure 2B According to some embodiments of the present disclosure, Figure 2A A cross-sectional view taken along line II';

[0034] Figure 3 is a schematic cross-sectional view of a welding device having a vertically irradiated laser;

[0035] Figure 4 is a conceptual diagram for explaining the principle of a welding device having a laser irradiated laterally (eg, horizontally) according to some embodiments of the present disclosure;

[0036] Figure 5 is a side cross-sectional view of a welding apparatus with a laser irradiated laterally (e.g., horizontally) according to some embodiments of the present disclosure;

[0037] Fig. 6A is a projected perspective view of a vortex forming portion viewed from a vortex gas outlet according to some embodiments of the present disclosure;

[0038] Figure 6B is a projection perspective view of a vortex forming portion viewed from a gas layer forming portion according to some embodiments of the present disclosure;

[0039] Figure 6C and Fig.6D The present invention conceptually illustrates some embodiments of the present invention. Fig. 6A and Figure 6B A schematic front view of a vortex forming portion in FIG.

[0040] Fig. 6E is a schematic diagram of a vortex forming part viewed from a gas layer forming part according to some embodiments of the present disclosure;

[0041] FIG. 7A to FIG. 7C An implementation of a welding apparatus with a laser irradiated laterally (eg, horizontally) according to some embodiments of the present disclosure is shown;

[0042] Figure 8 shows simulation data for verifying the effect of supplying a high concentration of gas (N2) to a welding area according to some embodiments of the present disclosure;

[0043] Fig.9A shows simulation data for verifying the behavior velocity of nitrogen in a vortex formation space according to some embodiments of the present disclosure;

[0044] Fig. 9B Some embodiments of the present disclosure are shown Fig.9A The measurement position in

[0045] Fig. 9C shows simulation data of the behavior velocity of nitrogen in a welding zone according to some embodiments of the present disclosure;

[0046] Fig.9D shows simulation data obtained by viewing the flow path of vortex gas according to some embodiments of the present disclosure; and

[0047] Fig.10 is an exemplary view of a module in which secondary batteries manufactured by the welding apparatus of the present disclosure are arranged according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0048] Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims shall not be narrowly interpreted as general or dictionary meanings, but shall be interpreted as meanings and concepts consistent with the technical ideas of the present disclosure based on the principle that the inventor can appropriately define the concepts of the terms as his / her own dictionary writer to describe his / her invention in an appropriate manner.

[0049] The embodiments described in this specification and the configurations shown in the accompanying drawings are only some of the embodiments of the present disclosure and do not represent all of the technical spirit, aspects and features of the present disclosure. Therefore, it should be understood that from the time of filing this application, there may be various equivalents and modifications that can replace or modify the embodiments described herein.

[0050] It will be understood that when an element or layer is referred to as being "on," "linked to," "connected to," or "coupled to" another element or layer, it may be directly on, directly linked to, directly connected to, or directly coupled to the other element or layer, or one or more intervening elements or layers may also be present. When an element or layer is referred to as being "directly on," "directly linked to," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers. For example, when a first element is described as being "coupled to" or "coupled to" a second element, the first element may be directly coupled to or directly coupled to the second element, or the first element may be indirectly coupled to or indirectly coupled to the second element via one or more intermediate elements.

[0051] In the figure, for the sake of clarity, the sizes of various elements, layers, etc. may be exaggerated. The same reference numerals represent the same elements. As used herein, the term "and / or" includes any combination and all combinations of one or more of the relevant listed items. In addition, when describing the embodiments of the present disclosure, the use of "may" relates to "one or more embodiments of the present disclosure". The expressions such as "at least one (kind / person) in ... " and "any one (kind / person) in ... " modify the entire row of elements after a row of elements without modifying the individual elements of the row. When phrases such as "at least one (kind / person) in A, B and C", "at least one (kind / person) in A, B or C", "at least one (kind / person) selected from the group of A, B and C" or "at least one (kind / person) selected from A, B and C" are used to specify a row of elements A, B and C, the phrase can refer to any and all suitable combinations or subsets of A, B and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the term "use" and variations thereof may be considered synonymous with the term "utilize" and variations thereof, respectively. As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation rather than as terms of degree, and are intended to account for the inherent deviations in measurements or calculations that one of ordinary skill in the art would recognize.

[0052] It will be understood that, although the terms first, second, third, etc. can be used here to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teaching of the exemplary embodiment, the first element, component, region, layer or part discussed below can be referred to as a second element, component, region, layer or part.

[0053] For ease of description, spatially relative terms such as "under", "below", "below", "above", "on", etc. may be used herein to describe the relationship of one element or feature to another element or features as shown in the figure. It will be understood that in addition to the orientation depicted in the figure, the spatially relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the figure is turned over, the element described as "under" or "below" other elements or features will then be oriented to be "above" or "on" the other elements or features. Therefore, the term "under" can cover both above and below. The device can be oriented otherwise (rotated 90 degrees or in other orientations), and the spatially relative descriptors used here should be interpreted accordingly.

[0054] The terms used herein are for the purpose of describing the embodiments of the present disclosure, and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "one" and "one (kind / person)" are also intended to include plural forms. It will also be understood that when the terms "include", "comprise" and / or its variations are used in this specification, the features, wholes, steps, operations, elements and / or components stated are indicated, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their groups are not excluded.

[0055] In addition, any numerical range disclosed and / or narrated herein is intended to include all sub-ranges of the same numerical precision contained in the narrated range. For example, the range of "1.0 to 10.0" is intended to include all sub-ranges between the narrated minimum value 1.0 and the narrated maximum value 10.0 (and including the narrated minimum value 1.0 and the narrated maximum value 10.0), that is, with a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6 as an example. Any maximum numerical limit narrated here is intended to include all lower numerical limits contained therein, and any minimum numerical limit narrated in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to amend this specification and claims to clearly narrate any sub-range contained in the scope clearly narrated here. All such scopes are intended to be inherently described in this specification so that the modification of any such sub-range clearly narrated will meet the requirements of patent law.

[0056] Referring to two compared elements, features, etc. as "the same" may mean that they are "substantially the same." Thus, the phrase "substantially the same" may include situations with deviations that are considered low in the art (e.g., 5% or less). Additionally, when a parameter is referred to as being uniform in a given area, this may mean that it is uniform in terms of average value.

[0057] Throughout the specification, unless otherwise stated, each element may be in the singular or in the plural.

[0058] Throughout the specification, when "A and / or B" is stated, it means A, B, or A and B unless otherwise stated. That is, "and / or" includes any combination or all combinations of multiple listed items. When "C to D" is stated, it means C or greater and D or less unless otherwise stated.

[0059] The terminology used herein is for the purpose of describing embodiments of the present disclosure and is not intended to be limiting of the present disclosure.

[0060] Examples of the secondary battery include a coin type, a cylindrical type, a prismatic type, a pouch type, and the like.

[0061] Cylindrical and prismatic secondary batteries to which the welding apparatus of the present disclosure is applicable will be briefly described.

[0062] Figure 1 A cylindrical secondary battery according to some embodiments of the present disclosure is shown.

[0063] like Figure 1As shown in , the secondary battery may include an electrode assembly 30, a case accommodating the electrode assembly 30 and an electrolyte therein, a cap assembly 50 coupled to an opening of the case 10 to seal the case 10, and an insulating plate 37 located between the electrode assembly 30 and the cap assembly 50 inside the case 10.

[0064] The electrode assembly 30 may include a separator 32 and first and second electrodes 33 and 31 , and may be wound in a core shape, with the first and second electrodes 33 and 31 positioned with the separator 32 interposed therebetween.

[0065] The first electrode 33 includes a first substrate and a first active material layer on the first substrate. The first lead tab 35 may extend outward from a first non-coating portion of the first substrate where the first active material layer is not located, and the first lead tab 35 may be electrically connected to the cap assembly 50 .

[0066] The second electrode 31 has a second substrate and a second active material layer on the second substrate. The second lead tab 34 may extend outward from a second non-coated portion of the second substrate where the second active material layer is not located, and the second lead tab 34 may be electrically connected to the housing 10. The first lead tab 35 and the second lead tab 34 may extend in opposite directions.

[0067] The first electrode 33 may be used as a positive electrode. In such an embodiment, the first substrate is made of, for example, aluminum foil, and the first active material layer may include, for example, a transition metal oxide. The second electrode 31 may be used as a negative electrode. In such an embodiment, the second substrate is made of, for example, copper foil or nickel foil, and the second active material layer includes, for example, graphite.

[0068] The separator 32 prevents or substantially reduces short circuit between the first electrode 33 and the second electrode 31 while allowing lithium ions to move between the first electrode 33 and the second electrode 31. The separator 32 may be made of, for example, a polyethylene film, a polypropylene film, a polyethylene-polypropylene film, or the like.

[0069] The case 10 accommodates the electrode assembly 30 and the electrolyte, and forms the appearance of the secondary battery together with the cap assembly 50. The case 10 may have a substantially cylindrical body portion 12 and a bottom portion 11 connected to one side of the body portion 12 (e.g., connected to one end of the body portion 12). An inwardly deformed crimping portion 13 (e.g., a crimping piece) may be formed in the body portion 12, and an inwardly bent crimping portion 15 (e.g., a crimping piece) may be formed at an open end of the body portion 12.

[0070] The crimping portion 13 can reduce or prevent movement of the electrode assembly 30 inside the case 10 and can facilitate placement of the gasket and the cap assembly 50. The crimping portion 15 can securely fix the cap assembly 50 by pressing the edge of the case 10 against the gasket 14. For example, the case 10 can be formed of nickel-plated iron.

[0071] The cover assembly 50 may be fixed to the inside of the crimping portion 15 by the gasket 14 to seal the housing 10. The cover assembly 50 may include an upper cover, a safety vent, a lower cover, an insulating member, and a sub-board; however, the embodiments of the present disclosure are not limited thereto and may be modified in various suitable ways.

[0072] The upper cover may be located at the uppermost portion of the cap assembly 50. The upper cover may include a terminal portion protruding upward and connected to an external circuit, and an outlet for exhausting gas may be arranged around the terminal portion.

[0073] The safety vent may be positioned below the upper cover. The safety vent may include a protruding portion protruding downward and connected to the sub-board, and at least one notch may be formed in the safety vent around the protruding portion.

[0074] When gas is generated due to overcharge or abnormal operation of the secondary battery, the raised portion is deformed upward due to pressure and separated from the sub-plate, and the safety vent is cut (e.g., ruptured or torn) along the notch. The cut safety vent can prevent the secondary battery from exploding or significantly reduce the possibility of the secondary battery exploding by allowing gas to be discharged to the outside.

[0075] The lower cover may be below the safety vent. The lower cover may have a first opening for exposing a raised portion of the safety vent and a second opening for gas discharge. An insulating member may be located between the safety vent and the lower cover to insulate the safety vent and the lower cover.

[0076] The sub-plate may be below the lower cover. The sub-plate may be fixed to the lower surface of the lower cover to block the first opening of the lower cover, and the raised portion of the safety vent may be fixed to the sub-plate. The first lead tab 35 led out from the electrode assembly 30 may be fixed to the sub-plate. Thus, the upper cover, the safety vent, the lower cover, and the sub-plate may be electrically connected to the first electrode 33 of the electrode assembly 30.

[0077] The insulating plate 37 may be positioned to contact the electrode assembly 30 below the curling portion 13. The insulating plate 37 may have a tab opening through which the first lead tab 35 is led out. The cap assembly 50 electrically connected to the first electrode 33 through the first lead tab 35 may face the electrode assembly 30 with the insulating plate 37 interposed between the cap assembly 50 and the electrode assembly 30, and may be kept insulated (e.g., electrically insulated) from the electrode assembly 30 by the insulating plate 37. In addition, a different insulating plate 36 may be included for insulation between the electrode assembly 30 and the bottom 11 of the case 10.

[0078] Figure 2A is a top perspective view of a prismatic secondary battery according to some embodiments of the present disclosure. Figure 2B According to some embodiments of the present disclosure, Figure 2A A cross-sectional view taken along line II'.

[0079] First, we will describe Figure 2A Appearance of a prismatic secondary battery shown in FIG.

[0080] The case 51 defines the overall appearance of the prismatic secondary battery, and may be made of a conductive metal such as aluminum, an aluminum alloy, nickel-plated steel, etc. In addition, the case 51 may provide a space therein for accommodating an electrode assembly.

[0081] The cap assembly 60 may include a cap plate 61 covering the opening of the housing 51. The housing 51 and the cap plate 61 may be made of a conductive material. Here, the first terminal 62 and the second terminal 63 may be electrically connected to the corresponding positive electrode and negative electrode (or negative electrode and positive electrode) inside the housing, and may be installed to protrude outward through the cap plate 61.

[0082] The cap plate 61 may be provided with an electrolyte injection port 64 formed for mounting a sealing plug (or sealing pin) and a vent 66 formed with a notch 65. The vent 66 is for discharging gas generated inside the secondary battery.

[0083] Reference Figure 2B , the internal structure of the prismatic secondary battery and the coupling structure with the cap assembly 60 will be further described below.

[0084] like Figure 2B As shown in , a prismatic secondary battery may include an electrode assembly 40 , a first current collector 41 , a first terminal 62 , a second current collector 42 , a second terminal 63 , a case 51 , and a cap assembly 60 .

[0085] The electrode assembly 40 may be formed by winding or stacking a stack of a first electrode plate, a separator, and a second electrode plate formed as a thin plate or a film. When the electrode assembly 40 is a wound stack, the winding axis may be parallel to the longitudinal direction of the housing 51. In some other embodiments, the electrode assembly 40 may be a stacked type rather than a wound type, and the shape of the electrode assembly 40 is not limited in the present disclosure. In addition, the electrode assembly 40 may be a Z stacked electrode assembly in which the positive electrode plate, the separator, and the negative electrode plate are sequentially stacked and then bent into a Z stack. In addition, one or more electrode assemblies may be stacked so that the long sides of the electrode assemblies are adjacent to each other and accommodated in the housing, and the number of electrode assemblies in the housing is not limited in the present disclosure. The first electrode plate of the electrode assembly may be used as a negative electrode, and the second electrode plate may be used as a positive electrode, and vice versa.

[0086] The first electrode plate may be formed by applying a first electrode active material (such as graphite or carbon) to a first electrode current collector formed of a metal foil (such as copper, copper alloy, nickel or nickel alloy). The first electrode plate may include a first electrode tab 43 (e.g., a first uncoated portion) as an area where the first electrode active material is not applied. The first electrode tab 43 may be used as a current flow path between the first electrode plate and the first current collector 41. In some embodiments, when manufacturing the first electrode plate, the first electrode tab 43 may be formed by pre-cutting to protrude to one side of the electrode assembly 40, or the first electrode tab 43 may protrude to one side of the electrode assembly 40 more than the diaphragm (e.g., farther than the diaphragm or beyond the diaphragm) without separate cutting.

[0087] The second electrode plate can be formed by applying a second electrode active material (such as a transition metal oxide) on a second electrode current collector formed of a metal foil (such as aluminum or an aluminum alloy). The second electrode plate may include a second electrode terminal tab 44 (e.g., a second uncoated portion) as an area where the second electrode active material is not applied. The second electrode terminal tab 44 may be used as a current flow path between the second electrode plate and the second current collector 42. In some embodiments, when manufacturing the second electrode plate, the second electrode terminal tab 44 may be formed by pre-cutting to protrude to the other side (e.g., the opposite side) of the electrode assembly, or the second electrode plate may protrude to the other side of the electrode assembly more than the diaphragm (e.g., farther than the diaphragm or beyond the diaphragm) without separate cutting.

[0088] In some embodiments, the first electrode tab 43 may be positioned on the left side of the electrode assembly 40, and the second electrode tab 44 may be positioned on the right side of the electrode assembly 40. In some other embodiments, the first electrode tab 43 and the second electrode tab 44 may be positioned on one side of the electrode assembly 40 in the same direction. Here, for ease of description, the left side and the right side are described as follows: Figure 1 The position of the secondary battery is defined by a secondary battery oriented in the middle, and changes when the secondary battery is rotated left to right or up to down.

[0089] The separator prevents or substantially reduces the short circuit between the first electrode and the second electrode while allowing lithium ions to move between the first electrode and the second electrode. For example, the separator may be made of a polyethylene film, a polypropylene film, a polyethylene-polypropylene film, or the like.

[0090] The first electrode tab 43 of the first electrode plate and the second electrode tab 44 of the second electrode plate may be respectively located at both ends (e.g., opposite ends) of the electrode assembly 40. In some embodiments, the electrode assembly 40 may be housed in the case 10 together with the electrolyte. In addition, in the electrode assembly 40, the first current collector 41 and the second current collector 42 may be respectively welded and connected to the first electrode tab 43 of the first electrode plate and the second electrode tab 44 of the second electrode plate exposed on both sides, and then respectively located at the first electrode tab 43 of the first electrode plate and the second electrode tab 44 of the second electrode plate.

[0091] In the secondary battery including the cylindrical and prismatic secondary batteries described above, laser welding may be used to join its components. Examples of laser welding may include joining of the terminals 62, 63 with the connecting member 67 and joining of the vent 66 with the Figure 2A The engagement of the cover plate 61 in the cover assembly 60 described in .

[0092] When welding is performed using a laser, energy is concentrated. When the base material (e.g., a member to be welded) is irradiated with a laser beam, heat is generated and transferred to adjacent elements. In this case, smoke and spatter are generated due to the large energy. The generated smoke and spatter interfere with the transmission of the laser beam, which may cause quality risks.

[0093] Figure 3 is a schematic cross-sectional view of a welding device with a vertically irradiated laser.

[0094] For welding, the members to be welded 71, 72 are welded by installing a shielding device 80 at the top of the welding apparatus and vertically irradiating a laser beam from the top to the bottom through a chamber 82 therein (ie, the irradiated laser beam is indicated by "L").

[0095] The components to be welded 71 and 72 can be placed on a welding fixture 81 installed in the shielding device 80. The welding fixture 81 can be made of copper material to fit the shape of the specific components to be welded, and is used to align the positions of the components to be welded, ensure welding accuracy, improve the convenience of welding, etc. Here, reference numeral 73 indicates a region (e.g., welding region) to be welded between the components to be welded 71 and 72, and reference numeral 83 indicates a gas (e.g., nitrogen, argon, helium, etc.) supplied to the chamber 82 in order to improve (e.g., increase) weld formability and weld quality.

[0096] When welding is performed by irradiating the laser beam vertically downward in this manner, the spatter 74 and the smoke 75 as described above may flow into the product (e.g., secondary battery) by falling toward the members to be welded 71 and 72 positioned below. This may be further exacerbated if the shielding device 80 moves up and down during welding.

[0097] In the prior art, in order to perform welding in a secondary battery having a terminal structure in which the terminal is positioned at the top thereof, as Figure 3 The laser beam is irradiated from top to bottom as shown. In this case, spatter 74 generated and falling into the welding area 73 will rebound and fall again due to gravity, which will cause defects by contaminating the welding area 73 and flowing into the battery.

[0098] Laser welding equipment with vertically irradiated lasers uses a suction mechanism to collect and remove spatter 74 and fume 75. However, this may have limitations because it does not collect (eg, 100% collect or completely collect) all spatter and fume generated in the welding area 73.

[0099] Figure 4 is a conceptual diagram for explaining the principle of a welding apparatus with a laser irradiated laterally (eg, horizontally) according to some embodiments of the present disclosure.

[0100] The welding device (or laser welding device) with a laser that irradiates laterally (e.g., horizontally) and represented by the reference numeral 100 may include: a chamber 110, through which a laser beam L passes laterally (e.g., horizontally) to irradiate a welding area 73 between components to be welded 71, 72; and a vortex forming space 112, which connects the chamber 110 and the welding area 73 between components to be welded 71, 72 and is defined to supply welding gas to the welding area and discharge spatter 74 and smoke 75 into the chamber 110 by generating vortex gas.

[0101] The components to be welded 71 and 72 may both be connecting components for connecting the cap assembly (or cap plate) and the current collector of the secondary battery, but are not limited thereto. For example, the components to be welded 71 and 72 may be the cap plate and the exhaust port joined to the cap plate, or may alternatively be other objects for welding instead of the objects of the secondary battery.

[0102] For transverse (e.g., horizontal) welding of the components 71, 72 to be welded, the welding apparatus 100 with a transverse (e.g., horizontal) irradiated laser according to the present disclosure may be equipped with a transverse (e.g., horizontal) mounted welding jig 200 for the components 71, 72 to be welded. The components 71, 72 to be welded are placed and mounted on the welding jig 200 and are irradiated by the laser beam L transversely (e.g., horizontally).

[0103] The end of the chamber 110 included in the welding device 100 (i.e., the vortex forming space 112 connecting the chamber 110 and the welding area 73) may be in the form of a tube. The tubular space 112 is shown as having a conical shape having a diameter that narrows from the chamber 110 to the welding area 73; however, the embodiments of the present disclosure are not limited thereto. The vortex forming space 112 may be used to supply a gas 83 (such as nitrogen, argon, and helium) to the welding area 73, and to discharge the spatter 74 and the fume 75 into the chamber 110 with a strong force by generating a vortex of the gas 83. Figure 4 The concept of the spiral release of smoke 75 and splash 74 along the vortex of gas 83 through chamber 110 is schematically shown.

[0104] The spatter 74 generated by the lateral (e.g., horizontal) irradiation of the laser during welding according to the present disclosure can accumulate under the welding device 100 or accumulate in the vortex forming space 112 (rather than the welding area 73). Even if the welding device 100 moves laterally (e.g., horizontally) during welding, the spatter 74 will not flow to the welding area 73, so there is no possibility of entering the secondary battery. In addition, smoke 75 can be generated and collected in the chamber 110 simultaneously (e.g., concurrently) with the strong vortex gas generated in the vortex forming space 112, and then can be quickly and strongly released to the outside. Not only smoke 75, but also spatter 74 can be released to the outside along the vortex gas.

[0105] Thus, some embodiments of the present disclosure are directed to reducing (e.g., minimizing) the likelihood of spatter 74 and smoke 75 flowing into a secondary battery, and completely (e.g., 100%) collecting and releasing all spatter 74 and smoke 75 through lateral (e.g., horizontal) irradiation of a laser beam and improvements in the structure of welding equipment.

[0106] Now we will further describe the method for implementing Figure 4Some embodiments of the principles of the present disclosure are described in the accompanying drawings.

[0107] Figure 5 is a side cross-sectional view of a welding apparatus 100 having a laser irradiated laterally (eg, horizontally) according to some embodiments of the present disclosure.

[0108] As in Figure 4 As conceptually explained in FIG. 1 , the welding apparatus 100 having a laser irradiated laterally (eg, horizontally) may include a chamber 110 therein, and may be equipped with a welding jig 200 for mounting members 71 , 72 to be welded.

[0109] The welding apparatus 100 includes an eddy current forming portion 113 (see FIG. 1 ) in contact with the welding area 73 between the welding members 71 and 72. Figure 6B ), the vortex forming portion 113 is defined Figure 4 The structure of the vortex forming space 112 described in the figure. The vortex forming portion 113 may be in communication with the chamber 110, and a transparent glass shielding member 134 may be installed on the opposite side of the vortex forming portion 113 to seal the chamber 110. The laser beam L may be irradiated laterally (e.g., horizontally) from the outside of the transparent glass shielding member 134. The irradiated laser beam L may enter the chamber 110 through the glass shielding member 134, and exit from reference numerals 114 to 116 in the vortex forming portion 113 via the chamber 110 to weld the welding region 73 between the components 71, 72 to be welded.

[0110] Here, reference numeral 114 in the vortex forming portion 113 is an inlet from the perspective of the laser beam L, but because it is a position where the vortex gas formed in the vortex forming space 112 is emitted, it will be referred to as a vortex gas outlet 114 hereinafter. In addition, reference numeral 116 in the vortex forming portion 113 is an outlet from the perspective of the laser beam L, but because it is a position where a gas layer is formed to supply gas to the welding area 73, it will be referred to as a gas layer forming portion 116 hereinafter (which will be further described below).

[0111] The vortex gas outlet 114 of the vortex forming portion 113 may be as follows: Figure 4 The gas layer forming portion 116 may be opened to communicate with the chamber 110 as described in the foregoing, and the gas layer forming portion 116 may be opened to supply gas to the welding region 73. The outer shape of the vortex forming portion 113 may be defined by an outer wall 118 separated from the welding jig 200.

[0112] A gas (such as nitrogen) may be supplied to the vortex forming portion 113 through a gas injection port 120. A further description of supplying gas to the vortex forming portion 113 will be provided below with reference to other drawings. The gas injection port 120 may be separated from the chamber 110 by a partition wall 122 (which may be formed by placing a gas injection port 122 between the chamber 110 and the gas injection port 122). Fig. 6A and Figure 6B The gas introduction pipe 121 described in the embodiment is separated from the chamber 110).

[0113] The chamber 110 further includes a release port 132 for releasing the vortex gas from the vortex gas outlet 114 of the vortex forming portion 113 out of the chamber 110. The release port 132 may be equipped with a suction fan to more effectively release the vortex gas; however, the embodiments of the present disclosure are not limited thereto. The released vortex gas may include smoke 75 and spatter 74 generated in the welding area 73 during laser welding.

[0114] The chamber 110 may be formed with a first exhaust port 131 to smoothly release the vortex gas from the release port 132. In some embodiments, by supplying air from the outside to the chamber 110 via the first exhaust port 131, the vortex gas is easily released through the release port 132. However, in some other embodiments, the first exhaust port 131 is a simple hole for equalizing the atmospheric pressure and the pressure within the chamber 110.

[0115] In addition, the chamber 110 may be formed with other second exhaust ports 133a, 133b, 133c to further promote the release of the vortex gas through the release port 132. These second exhaust ports 133a, 133b, 133c may be holes for equalizing the atmospheric pressure and the pressure in the chamber 110. Figure 5 The number of the second exhaust ports is shown as three, but the present disclosure is not limited thereto.

[0116] In addition, the chamber 110 may include a glass shielding exhaust port 130. The glass shielding exhaust port 130 may prevent the glass shielding member 134 from fogging or contamination, or significantly reduce the possibility thereof. To this end, the glass shielding exhaust port 130 may be designed to be positioned adjacent to the glass shielding member 134 and blow in or out a gas (such as air) to flow along the surface of the glass shielding member 134; however, embodiments of the present disclosure are not limited thereto.

[0117] Hereinafter, the detailed structure and operation of the vortex flow forming portion 113 will be described.

[0118] Fig. 6A is a projected perspective view of the vortex forming portion 113 viewed from the vortex gas outlet 114 according to some embodiments of the present disclosure. Figure 6B is a projection perspective view of the vortex forming portion 113 viewed from the gas layer forming portion 116 according to some embodiments of the present disclosure.

[0119] exist Fig. 6A and Figure 6B In the embodiment shown in FIG. 1 , the outer wall 118 may define the contour of the vortex forming portion 113 . The outer shape of the vortex gas outlet 114 may be defined by the first end 118 a of the outer wall 118 , and the outer shape of the gas layer forming portion 116 may be defined by the second end 118 b of the outer wall 118 .

[0120] The first end 118a may be connected to a gas introduction pipe 121 that communicates with the gas injection port 120. The gas introduction pipe 121 may be branched into a first branch pipe 122a and a second branch pipe 122b by communicating with the interior of the first end 118a. The first branch pipe 122a may have an outlet 127a connected to a first manifold 124a, and the second branch pipe 122b may have an outlet 127b connected to a second manifold 124b. The first manifold 124a may be in communication with two gas supply channels 123a, 123b, and the second manifold 124b may be in communication with two other gas supply channels 123c, 123d.

[0121] According to this structure, when a gas such as nitrogen is injected through the gas injection port 120, the gas can flow along the gas introduction pipe 121 and branch from the inside of the first end 118a into the first branch pipe 122a and the second branch pipe 122b. The gas entering the first branch pipe 122a can be transported to the second end 118b along the two gas supply channels 123a and 123b connected to the first manifold 124a. The gas entering the second branch pipe 122b can be transported to the second end 118b along the two gas supply channels 123c and 123d connected to the second manifold 124b.

[0122] The configuration of the gas supply channels 123a, 123b, 123c, 123d will be further described below.

[0123] The gas supply passage 123a may include an inflow end 128a communicating with the first manifold 124a to introduce gas, a closed end 125a blocked at the second end 118b, and an injection port 126a positioned at a distance from the closed end 125a to inject gas toward the vortex forming portion 113. Similarly, the gas supply passage 123b may include an inflow end 128b communicating with the first manifold 124a to introduce gas, a closed end 125b blocked at the second end 118b, and an injection port 126b positioned at a distance from the closed end 125b to inject gas toward the vortex forming portion 113.

[0124] Likewise, the gas supply passage 123c may include an inflow end 128c communicating with the second manifold 124b to introduce gas, a closed end 125c blocked at the second end 118b, and an injection port 126c positioned at a distance from the closed end 125c to inject gas toward the vortex forming portion 113. In addition, the gas supply passage 123d may include an inflow end 128d communicating with the second manifold 124b to introduce gas, a closed end 125d blocked at the second end 118b, and an injection port 126d positioned at a distance from the closed end 125d to inject gas toward the vortex forming portion 113.

[0125] exist Fig. 6A and Figure 6B , the gas supply channels 123a, 123b, 123c, 123d are shown as being formed in the wall of the outer wall 118 and extending to the second end 118b; however, the embodiments of the present disclosure are not limited thereto. For example, the gas supply channels 123a, 123b, 123c, 123d may extend to the second end 118b along the surface of the outer wall 118 in the space within the vortex forming portion 113. In addition, the number of gas supply channels 123a, 123b, 123c, 123d is Fig. 6A and Figure 6B However, the embodiments of the present disclosure are not limited thereto. In addition, the first branch pipe 122a and the second branch pipe 122b may be omitted. In this case, the gas flowing into the gas introduction pipe 121 may directly enter the first manifold 124a and the second manifold 124b, and then enter the gas supply channels 123a, 123b, 123c, 123d connected to the respective manifolds.

[0126] Now refer to Figure 6C , 6D and 6E further describe the operation of the vortex forming portion 113 constructed as above.

[0127] Figure 6C and Fig.6D The present invention conceptually illustrates some embodiments of the present invention. Fig. 6A and Figure 6B Schematic front view of the vortex forming portion 113 in FIG. Fig. 6E is a schematic left side view of the vortex forming portion 113 viewed from the gas layer forming portion 116 according to some embodiments of the present disclosure.

[0128] The gas G injected through the gas injection port 120 may enter the first manifold 124 a and the second manifold 124 b through the gas introduction pipe 121 . Figure 6C and Fig.6DThe schematic diagram of the first branch pipe 122a and the second branch pipe 122b is omitted for the sake of convenience of explanation and better understanding of the operation. Figure 6C and Fig.6D yes Fig. 6A and Figure 6B The front view, so Figure 6C and Fig.6D Only the first manifold 124a and the gas supply channels 123a, 123b connected thereto are shown.

[0129] The gas G entering the first manifold 124a and the second manifold 124b can be distributed to the gas supply channels 123a, 123b, 123c, 123d connected to the respective manifolds. The distributed gas can flow to the gas layer forming portion 116 through the gas supply channels 123a, 123b, 123c, 123d. The gas G blocked at the closed ends 125a, 125b, 125c, 125d of the respective gas supply channels can be ejected from the ejection ports 126a, 126b, 126c, 126d positioned at a set or predetermined distance from the respective closed ends.

[0130] Since the injection ports 126a, 126b, 126c, and 126d are open toward the vortex forming space 112, the injected gas G' can be guided toward the vortex forming space 112. The injection ports 126a, 126b, 126c, and 126d can each have a relatively smaller diameter than the diameter of the gas supply passages 123a, 123b, 123c, and 123d. Therefore, the gas G' injected through the injection ports 126a, 126b, 126c, and 126d can enter the vortex forming space 112 at a high speed.

[0131] Since the gas G′ is ejected from the ejection ports 126a, 126b, 126c, 126d in this manner, a gas layer 129 (see, for example, FIG. 114 ) can be formed in the gas layer forming portion 116. Fig.6D ). The gas layer 129 can play a role in supplying high-concentration gas to the welding area 73. Figure 8 The effect of increasing the concentration of gas layer 129 is shown in FIG.

[0132] Fig.6D It is shown that the gas G′ injected from the injection ports 126 a , 126 b , 126 c , 126 d forms a vortex gas G″ in the vortex forming space 112 and the vortex gas G″ is discharged to the vortex gas outlet 114 . The vortex gas G″ discharged from the vortex gas outlet 114 enters the chamber 110 . Fig. 6E The formation principle of the vortex gas G" is shown in FIG.

[0133] Reference Fig. 6E, when viewed from the gas layer forming portion 116, the direction of the injection from each injection port 126a, 126b, 126c, 126d is toward the right circumferential direction (i.e., clockwise) relative to the inner wall 127. Therefore, the gas G' rapidly injected from the injection ports 126a, 126b, 126c, 126d is transformed into a vortex gas G" in the form of a vortex rotating clockwise along the inner wall 127 in the vortex forming space 112, and spirally ejected through the vortex gas outlet 114. The ejected vortex gas G" enters Figure 5 The chamber 110 shown in FIG. 1 is finally released through the release port 132. If a suction fan is installed at the release port 132 for suction, the vortex gas G" can be released more effectively.

[0134] like Fig. 6E As shown in the figure, the direction of injection from each injection port 126a, 126b, 126c, 126d for forming the vortex gas G" can be within the range of the angle a formed by the inner wall 127 and the straight line (Oc straight line) connecting the center O of the gas layer forming part 116 or the vortex forming space 112 with the center c of each gas supply channel 123a, 123b, 123c, 123d. However, in order to form a larger (e.g., optimal) vortex, it can be expected that the direction of injection from each injection port 126a, 126b, 126c, 126d is approximately 90° relative to the Oc straight line.

[0135] Fig. 6E According to some embodiments, the direction of the jets from the jet ports 126a, 126b, 126c, and 126d is clockwise when viewed from the gas layer forming portion 116. However, in some other embodiments, the direction of the jets from the jet ports 126a, 126b, 126c, and 126d is toward the left circumferential direction (i.e., counterclockwise) when viewed from the gas layer forming portion 116. In this case, the vortex direction of the vortex gas G" will be in the same direction as Fig. 6E Formed in the direction opposite to the direction of.

[0136] FIG. 7A to FIG. 7C A practical implementation of a welding apparatus 100 with a laser irradiated laterally (eg, horizontally) as described above is shown according to some embodiments of the present disclosure.

[0137] Fig. 7A The state in which the components to be welded 71, 72 are not mounted on the welding jig 200 is shown. The welding jig 200 is mounted on one side of the housing of the laser welding apparatus 100. The welding jig 200 has a mounting portion (e.g., component to be welded mounting portion) 202 for mounting the components to be welded 71, 72 thereon. As described above, the mounting portion 202 can be modified to suit the type, shape, etc. of each component to be welded. The vortex forming portion (e.g., Figure 5The gas layer forming portion 116 of the laser welding apparatus 100 is positioned in the mounting portion 202. When the components to be welded 71, 72 are mounted on the mounting portion 202, the gas layer forming portion 116 contacts the welding area 73 between the components to be welded 71, 72. The gas injection port 120 and the first exhaust port 131 are mounted on the upper surface of the housing of the laser welding apparatus 100. Second exhaust ports 133a, 133b and 133c are formed on the upper surface of the housing. The glass shielding exhaust port 130 is positioned on the right side of the housing. The release port 132 is positioned on the bottom of the housing.

[0138] Figure 7B FIG. 2 shows a state where components 71 and 72 to be welded are mounted on a welding fixture 200. Fig. 7A On the mounting portion 202 shown in .

[0139] Figure 7C FIG. 2 shows a state where the welding jig 200 is removed. Figure 7C , there is shown a vortex forming portion 113 in which the laser beam L is irradiated, a gas layer is formed, and a vortex gas is formed.

[0140] Figure 8 The simulation data for verifying the effect of supplying a high concentration gas (e.g., N2) to the welding area 73 in the welding apparatus 100 with a laser irradiated laterally (e.g., horizontally) according to some embodiments of the present disclosure are shown. As described above, by supplying gas to the vortex forming portion 113 through the gas injection port 120 to form the gas layer 129, the quality of laser welding can be improved (e.g., enhanced). Figure 8 , the highest nitrogen concentration (N2 mass fraction = 1.0) appears in the gas injection port 120 for injecting nitrogen (N2), and a relatively high level of nitrogen concentration (N2 mass fraction = 0.95 to 0.98) is supplied to the gas layer forming portion 116. Compared with the laser welding equipment of the prior art, this concentration is increased by 96%.

[0141] Fig.9A Simulation data for verifying the behavior velocity of nitrogen in the vortex forming space 112 in the welding apparatus 100 with a transversely (eg, horizontally) irradiated laser according to some embodiments of the present disclosure are shown.

[0142] Fig.9A The data in FIG. 1 are at a position of 20 mm from the gas layer forming portion 116 toward the chamber 110 (i.e., Fig. 9B The measurement of the behavior speed of nitrogen in the vortex forming space 112 is shown in FIG. Fig.9AAs shown in , the velocity in the vortex forming space 112 may be in the range of about 50 m / s at the center thereof to about 80 m / s at the periphery thereof. Fig.9A The clockwise arrow shown in refers to the above-mentioned vortex gas G″. As shown, the nitrogen gas forms a vortex and moves at a high speed in the vortex forming space 112.

[0143] Fig. 9C The simulation data of the behavior speed of nitrogen in the gas layer forming part 116 (i.e., the welding area 73) according to some embodiments of the present disclosure are shown. In the gas layer forming part 116, the nitrogen rotates at a speed of about 25m / s. Fig.9A In contrast, the velocity of the nitrogen gas rapidly increases from the gas layer forming portion 116 to the vortex forming space 112 .

[0144] Fig.9D Simulation data obtained by observing the flow path of vortex gas in welding equipment 100 with a laser irradiated laterally (e.g., horizontally) according to some embodiments of the present disclosure are shown. A flow path is shown in which a gas (e.g., nitrogen) injected through a gas injection port 120 forms a high-concentration gas layer in a gas layer forming portion 116, enters a chamber 110 via a vortex forming portion 113, and is then released through a release port 132. The simulation data verifies that the vortex gas is completely released through the release port 132 rather than toward the glass shield 134.

[0145] The welding method using a laser irradiated laterally (e.g., horizontally) according to the present disclosure will be further described below. The welding method may include: irradiating a laser beam laterally (e.g., horizontally) to a welding region between components to be welded; supplying gas to the welding region; and forming a vortex gas by the gas supplied to the welding region to discharge the vortex gas together with smoke and spatter generated during welding.

[0146] Here, the step of forming the vortex gas may be performed by circumferentially spraying the gas supplied to the welding area along the inner wall of the first end of the cylindrical hollow member (such as the vortex forming space 112) of the vortex forming portion 113. The gas sprayed circumferentially along the inner wall of the first end of the cylindrical hollow member may be discharged from the second end of the cylindrical hollow member in the form of a vortex while rotating along the inner wall.

[0147] Additionally, the exhausted vortex gas may be collected in the chamber, and the collected vortex gas may be released out of the chamber.

[0148] The welding method using the transversely (eg, horizontally) irradiated laser according to the present disclosure may be performed using the welding apparatus 100 having the transversely (eg, horizontally) irradiated laser described above.

[0149] Hereinafter, any material that can be used for a secondary battery according to the present disclosure will be further described below.

[0150] As the positive electrode active material, a compound capable of reversibly intercalating / deintercalating lithium (eg, a lithiated intercalation compound) may be used. For example, at least one composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and a combination thereof may be used.

[0151] The composite oxide may be a lithium transition metal composite oxide, and examples thereof may include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, nickel manganese-based oxides not containing cobalt, or combinations thereof.

[0152] As an example, a compound represented by any one of the following formulae may be used as the composite oxide: Li a A 1-b X b O 2- c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b- c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NeG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG bO2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn b O4(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4(0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3(0≤f≤2); and Li a FePO4(0.90≤a≤1.8).

[0153] In the above formula: A is Ni, Co, Mn or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element or a combination thereof; D is O, F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; and L 1 It is Mn, Al or a combination thereof.

[0154] A positive electrode for a lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may include a positive electrode active material, and may further include a binder and / or a conductive material.

[0155] The content of the positive electrode active material is in the range of about 90 wt % to about 99.5 wt % based on 100 wt % of the positive electrode active material layer, and the content of the binder and the conductive material are respectively in the range of about 0.5 wt % to about 5 wt % based on 100 wt % of the positive electrode active material layer.

[0156] The current collector may be aluminum (Al); however, embodiments of the present disclosure are not limited thereto.

[0157] The negative electrode active material may include a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of being doped and undoped with lithium, a transition metal oxide, and the like.

[0158] The material capable of reversibly inserting / deinserting lithium ions may be a carbon-based negative electrode active material, which may include, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon may include graphite (such as natural graphite or artificial graphite), and examples of amorphous carbon may include soft carbon, hard carbon, pitch carbide, mesophase pitch carbide, sintered coke, etc.

[0159] Si-based negative electrode active materials or Sn-based negative electrode active materials can be used as materials that can be doped and undoped with lithium. The Si-based negative electrode active materials can be silicon, silicon-carbon composites, SiO x (0 < x < 2), Si-based alloys, or combinations thereof.

[0160] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to some embodiments, the silicon-carbon composite is in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0161] The silicon-carbon composite can also include crystalline carbon. For example, the silicon-carbon composite can include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0162] The negative electrode for a lithium secondary battery can include a current collector and a negative electrode active material layer provided on the current collector. The negative electrode active material layer can include a negative electrode active material and can also include a binder and / or a conductive material.

[0163] For example, the negative electrode active material layer can include about 90 wt% to about 99 wt% of the negative electrode active material, about 0.5 wt% to about 5 wt% of the binder, and about 0 wt% to about 5 wt% of the conductive material.

[0164] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used as the binder. In the case where an aqueous binder is used as the negative electrode binder, a cellulose-based compound capable of imparting viscosity can also be included.

[0165] As the negative electrode current collector, one selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and combinations thereof can be used.

[0166] The electrolyte for a lithium secondary battery can include a non-aqueous organic solvent and a lithium salt.

[0167] The non-aqueous organic solvent acts as a medium through which ions participating in the electrochemical reaction of the battery can move.

[0168] The non-aqueous organic solvent can be a carbonate, an ester, an ether, a ketone, an alcohol solvent, an aprotic solvent, and can be used alone or in combination of two or more.

[0169] In addition, in the case of using a carbonate solvent, a mixture of a cyclic carbonate and a linear carbonate can be used.

[0170] According to the type of lithium secondary battery, the separator may be present between the first electrode plate (eg, negative electrode) and the second electrode plate (eg, positive electrode). As the separator, polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof may be used.

[0171] The separator may include a porous substrate and a coating layer on one or both surfaces of the porous substrate, the coating layer including an organic material, an inorganic material, or a combination thereof.

[0172] The organic material may include a polyvinylidene fluoride-based polymer or a (meth)acrylic polymer.

[0173] The inorganic material may include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite and combinations thereof, but is not limited thereto.

[0174] The organic material and the inorganic material may be mixed in one coating layer, or may be in the form that a coating layer including an organic material and a coating layer including an inorganic material are stacked on each other.

[0175] Fig.10 According to some embodiments of the present disclosure, a prismatic secondary battery (such as Figure 2A 2B or 2B). As the capacity of secondary batteries used to drive electric vehicles, etc. increases, a secondary battery module can be manufactured by arranging and connecting multiple secondary battery cells laterally and / or longitudinally. Multiple secondary batteries can be arranged in a space defined by a pair of facing end plates 68a, 68b and a pair of facing side plates 69a, 69b. The secondary batteries can be appropriately designed in arrangement (e.g., direction) and quantity to obtain desired voltage and current values.

[0176] Secondary battery modules can be integrated into battery packs for end products (e.g., electric vehicles). Battery packs can include components to which individual batteries are electrically connected and a housing that houses the components. The housing can include components including bus bars, cooling units, external terminals for electrically connecting batteries, and the like.

[0177] The battery pack may be mounted on (or in) a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle may be a four-wheel vehicle or a two-wheel vehicle, but is not limited thereto.

[0178] It should be understood that the embodiments described herein should be considered in a descriptive sense and not for limiting purposes. The description of features or aspects within each embodiment should generally be considered to be applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the drawings, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope defined by the appended claims and their equivalents.

Claims

1. A laser welding device, comprising: a chamber configured to allow a laser beam to be irradiated transversely to a welding area between components to be welded to pass therethrough; as well as The vortex forming portion is configured to connect the welding region between the members to be welded with the chamber, supply gas to the welding region, and form and discharge vortex gas.

2. The laser welding equipment according to claim 1, wherein: The vortex forming part comprises: a gas layer forming portion configured to supply the gas to the welding region; and A vortex gas outlet through which the vortex gas formed inside the vortex forming portion is emitted.

3. The laser welding equipment according to claim 1, wherein: The chamber includes a release port configured to release the vortex gas formed in the vortex forming portion out of the chamber. 4 . The laser welding apparatus according to claim 3 , further comprising a fan configured to draw the vortex gas from the release port.

5. The laser welding equipment according to claim 1, wherein: The chamber includes a transparent glass shield configured to allow the laser beam laterally irradiated from the outside to transmit.

6. The laser welding equipment according to claim 5, wherein: The chamber also includes a glass-shielded exhaust port communicating with the outside.

7. The laser welding equipment according to claim 1, wherein: The chamber includes at least one exhaust port communicating with the outside.

8. The laser welding equipment according to claim 1, wherein: The vortex forming portion includes a tapered tube whose diameter gradually decreases from the chamber to the welding area.

9. The laser welding equipment according to claim 1, wherein: The vortex forming part comprises: a gas injection port configured to inject the gas; and A gas supply channel is configured to supply the gas injected through the gas injection port to the welding area, and the gas supply channel includes: an inflow end, configured to introduce the gas injected through the gas injection port; a closed end, configured to block the advancement of the gas introduced into the inflow end; and an injection port, which is positioned at a certain distance from the closed end and is open toward the vortex forming part, and is configured to inject gas in a circumferential direction of the vortex forming part to form the vortex gas by causing the gas injected in the circumferential direction of the vortex forming part to rotate along the inner wall of the vortex forming part.

10. The laser welding device according to claim 9, wherein: The injection port is configured to allow the gas to be injected within a range of an angle formed by the inner wall of the vortex flow forming portion and a straight line connecting a center of the vortex flow forming portion and a center of the gas supply passage.

11. The laser welding equipment according to claim 9, wherein: The direction of injection from the injection port is 90° with respect to a straight line connecting the center of the vortex forming portion and the center of the gas supply passage.

12. The laser welding equipment according to claim 9, wherein: The injection port has a diameter smaller than a diameter of the gas supply passage.

13. The laser welding apparatus according to claim 9, wherein: The gas supply channel comprises a plurality of gas supply channels; and The vortex forming portion further includes a manifold configured to distribute the gas injected through the gas injection port to the respective inflow ends of the plurality of gas supply channels.

14. The laser welding apparatus according to claim 13, wherein: The manifold comprises a plurality of manifolds; and The vortex forming portion further includes a branch pipe configured to branch the gas injected into the plurality of manifolds through the gas injection port.

15. The laser welding equipment according to claim 9, wherein: The vortex gas injected from the injection port of the gas supply channel and formed in the vortex forming portion enters the chamber.

16. The laser welding device according to claim 1, wherein: The components to be welded are a cap plate and a current collector of a secondary battery.

17. A laser welding method, comprising the following steps: Irradiate the laser beam laterally to the welding area between the components to be welded; supplying gas to the welding area; as well as A swirling gas is formed by the gas supplied to the welding area to discharge the swirling gas together with fumes and spatters generated during welding.

18. The laser welding method according to claim 17, wherein: In the step of forming the vortex gas: forming the swirling gas by jetting the gas supplied to the welding area circumferentially along the inner wall of the first end of the cylindrical hollow member; and The formed vortex gas is discharged from the second end of the cylindrical hollow member while rotating along the inner wall of the cylindrical hollow member.

19. The laser welding method according to claim 17, further comprising collecting the vortex gas exhausted in the step of forming the vortex gas in a chamber, and releasing the collected vortex gas out of the chamber.

20. A secondary battery manufactured using the laser welding method according to claim 18.

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