Lid-daughter board assembly, secondary battery, and method for manufacturing secondary battery

Abstract

The invention discloses a secondary battery, a cover-daughter board assembly, and a method of manufacturing the secondary battery. The secondary battery includes: an electrode assembly; a daughter board assembly including a daughter board connected to the electrode assembly and a current collector bonded to a surface of the daughter board; and a cover assembly coupled to the daughter board assembly. The cover assembly includes a cover plate, and at least one open area is formed in the cover plate such that a portion of the daughter board is not covered by the cover plate.

Description

Technical Field

[0001] Aspects of embodiments of the present disclosure relate to a cap-subplate assembly, a secondary battery, and a method of manufacturing the secondary battery. Background Art

[0002] Secondary batteries are rechargeable batteries that can be charged and discharged multiple times. They are primarily used in a variety of applications, including electronic products (e.g., smartphones, laptops, and tablets), electric vehicles, solar power generation, and emergency power supplies. Specifically, lithium (Li)-ion batteries are used in various electronic products and electric vehicles due to their high energy density and high charge and discharge efficiency.

[0003] Depending on the shape of the housing, secondary batteries can be classified into cylindrical secondary batteries, prismatic secondary batteries, and pouch-shaped secondary batteries. Prismatic secondary batteries have a structure in which an electrode assembly is housed in a cylindrical metal can. The electrode assembly is inserted into the prismatic metal can, and then the prismatic metal can is sealed by welding the cover plate to the can. However, when there is a poor fit between the current collector and the terminal plate in such a secondary battery, the electrical characteristics of the secondary battery may deteriorate.

[0004] 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

[0005] An aspect of the present disclosure is to provide a cap-sub-plate assembly, a secondary battery, and a method of manufacturing the secondary battery, which are configured to solve at least one of the above-mentioned problems.

[0006] These and other aspects and features of the present disclosure will be described in or will be apparent from the following description of embodiments of the present disclosure.

[0007] According to some embodiments of the present disclosure, a secondary battery includes: an electrode assembly; a sub-plate assembly including a sub-plate connected to the electrode assembly and a current collector bonded to a surface of the sub-plate; and a cover assembly bonded to the sub-plate assembly, wherein the cover assembly includes a cover plate, and at least one open area is formed in the cover plate so that a portion of the sub-plate is not covered by the cover plate.

[0008] In some embodiments, the cap assembly further includes a terminal plate coupled to the cap plate, and the terminal plate is connected to the current collector.

[0009] In some embodiments, the current collector includes a planar portion and a protruding portion, and the protruding portion is connected to the terminal plate.

[0010] In some embodiments, the upper surface of the terminal plate includes an area welded to the protruding portion.

[0011] In some embodiments, the sub-plate and the electrode assembly are fixed via welding through the at least one open area, thereby forming a welding area on the sub-plate.

[0012] In some embodiments, the secondary battery further includes at least one outer cover positioned in the at least one open region formed in the cap plate.

[0013] In some embodiments, the cover plate includes a weld region welded along the open area.

[0014] In some embodiments, the secondary battery further includes a case accommodating the electrode assembly, wherein the case is fixed to the cap plate by welding.

[0015] In some embodiments, the secondary battery further includes a case accommodating the electrode assembly, the case including an open first side and an open second side opposite to the first side. The cap plate covers at least one of the first side and the second side, the cap assembly includes a terminal plate coupled to the cap plate, and a sealing member is located between the cap plate and the terminal plate.

[0016] In some embodiments, the shell includes: a first long side wall and a second long side wall, facing each other and spaced apart from each other; and a first short side wall and a second short side wall, facing each other and spaced apart from each other, wherein the area of the first short side wall and the second short side wall is smaller than the area of the first long side wall and the second long side wall.

[0017] In some embodiments, the cap assembly further includes a terminal plate coupled to the cap plate, the terminal plate includes an upper terminal plate and a lower terminal plate, and the upper terminal plate and the lower terminal plate are formed of different materials.

[0018] According to some embodiments of the present disclosure, a cover-sub-plate assembly includes: a sub-plate assembly including a sub-plate and a current collector coupled to the sub-plate; and a cover assembly coupled to the sub-plate assembly, wherein the cover assembly includes: a cover plate, and at least one open area is formed in the cover plate so that a portion of the sub-plate is not covered by the cover plate; a terminal plate coupled to the cover plate; and a sealing member located between the cover plate and the terminal plate.

[0019] In some embodiments, the current collector includes a planar portion and a protruding portion, and the protruding portion is connected to the terminal plate.

[0020] In some embodiments, the upper surface of the terminal plate includes an area welded to the protruding portion.

[0021] In some embodiments, the cover-subplate assembly further includes at least one outer cover positioned in the at least one open area formed in the cover plate.

[0022] According to some embodiments of the present disclosure, a method for manufacturing a secondary battery includes the following steps: preparing a cover-sub-plate assembly including a cover assembly and a sub-plate assembly, the sub-plate assembly including a sub-plate and a current collector coupled to the sub-plate; inserting an electrode assembly into a shell; coupling the cover-sub-plate assembly to an end of the shell; and welding the sub-plate to the electrode assembly, wherein at least one open area is formed in the cover assembly so that a portion of the sub-plate is not covered by the cover assembly.

[0023] In some embodiments, the cover assembly includes a cover plate, and the step of coupling the cover-subplate assembly to the end of the housing includes joining the end of the housing and the cover plate by welding.

[0024] In some embodiments, welding the sub-plate to the electrode assembly includes welding the sub-plate and the electrode assembly exposed through the at least one open area.

[0025] In some embodiments, the method further includes positioning an outer cover to the at least one open area of the cover assembly and welding the outer cover to the cover assembly.

[0026] In some embodiments, the step of preparing the cap-sub-plate assembly includes: forming a cap assembly by combining the cap plate and the terminal plate; forming a sub-plate assembly by combining the sub-plate and the current collector; and welding the terminal plate and the current collector.

[0027] According to the embodiments of the present disclosure, before being installed on the housing, it is possible to determine whether the current collector and the terminal plate are tightly fitted together, and the cap assembly and the sub-plate assembly can be combined with each other. Therefore, defects in the welded joint between the current collector and the terminal plate can be reduced, thereby improving the reliability of the secondary battery.

[0028] According to the embodiments of the present disclosure, it is possible to determine whether the current collector and the terminal plate are tightly fitted together, and whether the cap assembly and the sub-plate assembly can be combined with each other. Any defects in the combination between the current collector and the terminal plate can be easily detected, thereby making the manufacturing process easier and reducing manufacturing costs.

[0029] However, aspects and features of the present disclosure are not limited to the above-mentioned aspects and features, and other aspects and features not mentioned will be clearly understood by those skilled in the art 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: Figure 1 shows a perspective view illustrating a secondary battery according to some embodiments of the present disclosure; Figure 2shows a cross-sectional view illustrating a secondary battery according to some embodiments of the present disclosure; Figure 3 shows a perspective view illustrating a housing according to some embodiments of the present disclosure; Figure 4 Shown Shown Figure 2 An enlarged view of region R1 in FIG; Figure 5 A first cover assembly according to some embodiments of the present disclosure is shown; Figure 6 Shown Shown Figure 2 An enlarged view of region R2 in FIG; Figure 7 shows a second cover assembly according to some embodiments of the present disclosure; Figure 8 shows a perspective view of a cover-subplate assembly according to some embodiments of the present disclosure; Figures 9 to 12 A method of manufacturing a secondary battery according to some embodiments of the present disclosure is shown; Figure 13 A flowchart illustrating a method of manufacturing a secondary battery according to some embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0031] Hereinafter, 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 should not be interpreted as limited to the ordinary meaning or dictionary meaning, and should be interpreted as meanings and concepts consistent with the technical concept of the present disclosure based on the principle that the inventor can be his / her own lexicographer to appropriately define the concept of the term to best explain his / her invention.

[0032] The embodiments described in this specification and the configurations shown in the accompanying drawings are only some embodiments of the present disclosure and do not represent all technical concepts, aspects, and features of the present disclosure. Therefore, it should be understood that there may be various equivalents and modifications that can replace or modify the embodiments described herein when filing this application.

[0033] It will be understood that when an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it can be directly on, directly connected to, or directly coupled to the other element or layer, or one or more intervening elements or layers may be present. When an element or layer is referred to as being “directly on,” “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 “connected to” a second element, the first element can be directly coupled to or directly coupled to the second element, or the first element can be indirectly coupled to or indirectly coupled to the second element via one or more intervening elements.

[0034] In the figures, the dimensions of various elements, layers, etc. may be exaggerated for clarity. Identical reference numerals denote identical elements. As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items. Furthermore, when describing embodiments of the present disclosure, the use of "may" refers to "one or more embodiments of the present disclosure." Expressions such as "at least one of" and "any of" modify the entire list of elements when following a list of elements, rather than the individual elements in that list. When a phrase such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group of A, B, and C," or "at least one selected from among A, B, and C" is used to designate a list of elements A, B, and C, the phrase may refer to any suitable combination (or subset) of A, B, and C and all suitable combinations (or subsets), 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, not as terms of degree, and are intended to account for the inherent variation in measured or calculated values that one of ordinary skill in the art would recognize.

[0035] It will be understood that, although the terms first, second, third, etc. may be used herein 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 teachings of the exemplary embodiments, the first element, first component, first region, first layer or first part discussed below may be referred to as the second element, second component, second region, second layer or second part.

[0036] For ease of description, spatially relative terms such as “under,” “beneath,” “lower,” “above,” and “upper,” etc., may be used herein to describe the relationship of one element or feature to another element or feature as shown in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, an element described as “under” or “beneath” other elements or features would then be oriented “above” or “on” the other elements or features. Thus, the term “under” can encompass both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0037] 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 "a" and "an" are also intended to include the plural forms. It will also be understood that when the terms "comprises," "comprising," and / or variations thereof are used in this specification, the existence of the stated features, integers (entities), steps, operations, elements, and / or components is indicated, but the existence or addition of one or more other features, integers (entities), steps, operations, elements, components, and / or groups thereof is not excluded.

[0038] In addition, any numerical range disclosed and / or described herein is intended to include all subranges of the same numerical precision contained within the described range. For example, the range of "1.0 to 10.0" is intended to include all subranges between the described minimum value of 1.0 and the described maximum value of 10.0 (and including the described minimum value of 1.0 and the described maximum value of 10.0), that is, having 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. Any maximum numerical limit described herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit described in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to amend this specification and the claims to explicitly describe any subranges contained within the range explicitly described herein. All such ranges are intended to be inherently described in this specification so that modifications to explicitly describe any such subranges will meet the requirements.

[0039] 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 what is considered in the art to be low deviations (e.g., 5% or less). Additionally, when a parameter is referred to as being uniform in a given area, it may mean that it is uniform with respect to the average value.

[0040] Throughout the specification, unless stated otherwise, each element may be in the singular or in the plural.

[0041] Arranging an arbitrary element “on (or below)” or “upper (lower)” another element may mean that the arbitrary element may be positioned in contact with the upper (or lower) surface of that element, and another element may also be placed between the element and the arbitrary element positioned on (or below) that element.

[0042] Additionally, it will be understood that when a component is referred to as being “linked,” “coupled” or “connected” to another component, the elements may be directly “coupled,” “linked” or “connected” to each other or another component may be “interposed” between the components.

[0043] Throughout the specification, unless otherwise stated, when "A and / or B" is stated, it means A, B, or A and B. That is, "and / or" includes any and all combinations of multiple listed items. When "C to D" is stated, unless otherwise stated, it means C or greater and D or less.

[0044] Figure 1 A perspective view illustrating a secondary battery according to some embodiments of the present disclosure is shown. Figure 2 A cross-sectional view illustrating a secondary battery according to some embodiments of the present disclosure is shown.

[0045] Reference Figure 1 and Figure 2 , the secondary battery may include an electrode assembly 100 , a case 200 accommodating the electrode assembly 100 , a first sub-plate assembly 310 , a second sub-plate assembly 410 , a first cap assembly 350 , and a second cap assembly 450 .

[0046] The electrode assembly 100 may be included in the housing 200. The electrode assembly 100 may be formed by winding or stacking a laminate comprising a first electrode plate (not shown), a separator (not shown), and a second electrode plate (not shown). Each of the first electrode plate, the separator, and the second electrode plate may be formed from a thin plate or film. When the electrode assembly 100 is a wound laminate, the axis of its winding may be parallel to the length of the housing 200. Instead of a wound type, the electrode assembly 100 may be a stacked type, but the shape of the electrode assembly 100 of the present disclosure is not limited in this respect. Furthermore, the electrode assembly 100 may be a Z-stack electrode assembly in which the positive and negative electrode plates are arranged on opposite sides of a separator bent into a Z-shaped stack. Alternatively, one or more electrode assemblies 100 may be stacked and housed in the housing 200 so that their long sides are adjacent to each other, but the present disclosure is not limited in the number of electrode assemblies 100. In the electrode assembly 100, the first and second electrode plates may serve as the positive and negative electrodes, respectively, or vice versa.

[0047] The first electrode plate can be formed by applying a first electrode active material, such as graphite or carbon, to a first electrode current collector formed from a metal foil such as copper (Cu), a Cu alloy, nickel (Ni), or a Ni alloy. The first electrode plate may include a first electrode tab (or a first uncoated portion), which is a portion not coated with the first electrode active material. The first electrode tab may form a path for current flow between the first electrode plate and the first sub-plate assembly 310. In some examples, the first electrode tab may be formed by cutting the first electrode plate so that the first electrode tab protrudes from a first side of the electrode assembly and, without additional cutting, may protrude further from the first side than the separator.

[0048] The second electrode plate can be formed by applying a second electrode active material, such as a transition metal oxide, to a second electrode current collector formed from a metal foil such as aluminum (Al), an Al alloy, or the like. The second electrode plate may include a second electrode tab (or a second uncoated portion), which is a portion not coated with the second electrode active material. The second electrode tab may form a path for current flow between the second electrode plate and the second sub-plate assembly 410. In some examples, the second electrode tab may be formed by cutting the second electrode plate so that the second electrode tab protrudes from the second side of the electrode assembly and, without additional cutting, may protrude further from the second side than the separator.

[0049] In some examples, the first electrode tab may be located on the right end side of the electrode assembly, and the second electrode tab may be located on the left end side of the electrode assembly. The terms "left" and "right" used herein are for ease of reference. Figure 2 The description is made with respect to the secondary battery shown in , and the position may be changed as the secondary battery is rotated left and right or up and down.

[0050] In some embodiments, the electrolyte inlet 130 may be provided on the first outer cover 390. The electrolyte may be injected into the housing 200 through the electrolyte inlet 130. Figure 1 In the embodiment, the electrolyte inlet 130 is shown as being provided on the first outer cover 390, but is not limited to the depicted configuration. For example, the electrolyte inlet 130 may be provided on the first cover plate 360. After the injection of the electrolyte is completed, the electrolyte inlet 130 may be sealed using a sealing device such as a stopper.

[0051] In some embodiments, the exhaust port 110 may be provided on one side of the housing 200. For example, the exhaust port 110 may be provided on the lower surface of the housing 200. Here, the lower surface may refer to the surface facing downward when the secondary battery is installed. The exhaust port 110 may prevent the secondary battery from exploding or prevent a chain exothermic reaction of secondary batteries arranged in close proximity. For example, the exhaust port 110 may be configured to open when the internal pressure of the secondary battery exceeds a predetermined critical pressure. The critical pressure may be set differently depending on the application, material, purpose, etc. of the secondary battery. In another example, the exhaust port 110 may be configured to open when the internal temperature of the secondary battery exceeds a predetermined critical temperature.

[0052] exist Figure 1 , the exhaust port 110 is shown as a single exhaust port provided at the center of the side of the housing 200, but the exhaust port is not limited in this respect. Any number of exhaust ports 110 may be provided at any position in the side of the housing 200. For example, two or more exhaust ports 110 may be provided on the side of the housing 200.

[0053] Figure 3 A perspective view illustrating a housing according to some embodiments of the present disclosure is shown.

[0054] Reference Figure 2 and Figure 3 , the housing 200 may include long sidewalls 230 facing each other, short sidewalls 240 facing each other, an open first side 210 , and an open second side 220 .

[0055] In the figures, a first direction X may refer to an X-axis direction. A second direction Y may be orthogonal to the first direction X. The second direction Y may refer to a Y-axis direction. A third direction Z may be orthogonal to each of the first direction X and the second direction Y. The third direction Z may refer to a Z-axis direction.

[0056] The long sidewall 230 may include a first long sidewall portion and a second long sidewall portion. The first long sidewall portion and the second long sidewall portion may face each other. The first long sidewall portion and the second long sidewall portion may face each other while being spaced apart from each other along the second direction Y.

[0057] The short sidewall 240 may include a first short sidewall portion and a second short sidewall portion. The first short sidewall portion and the second short sidewall portion may face each other. The first short sidewall portion and the second short sidewall portion may face each other while being spaced apart from each other along the third direction Z. The areas of the first short sidewall portion and the second short sidewall portion may be smaller than the areas of the first long sidewall portion and the second long sidewall portion.

[0058] The open first side 210 and the open second side 220 may be provided on opposite sides of the housing 200. The open second side 220 may face the open first side 210. The open second side 220 and the open first side 210 may be spaced apart from each other while facing each other along the first direction X. Each of the open first side 210 and the open second side 220 may refer to an open area.

[0059] The housing 200 may be formed of a conductive metal such as Al, Al alloy, or Ni-plated steel.

[0060] The first cover plate (e.g. Figure 4 and Figure 5 360) can cover the opened first side 210 and can be coupled to the housing 200. The second cover plate (eg, Figure 6 and Figure 7 The first cover plate 360 and the second cover plate 460 may cover the opened second side 220 and may be coupled to the housing 200. For example, each of the first cover plate 360 and the second cover plate 460 may be welded to the housing 200. The first cover plate 360 and the second cover plate 460 may seal the housing 200.

[0061] Figure 4 Shown Shown Figure 2 Magnified view of region R1 in FIG.

[0062] Reference Figure 4 , the first sub-plate assembly 310 and the first cap assembly 350 may be coupled to the first side of the electrode assembly 100 .

[0063] The first sub-plate assembly 310 may be coupled to a first side of the electrode assembly 100 and may be electrically connected to a first electrode plate (eg, a positive electrode plate) of the electrode assembly 100 . The first sub-plate assembly 310 may include a first sub-plate 320 and a first current collector 330 .

[0064] The first sub-plate 320 may be coupled to the first electrode tab of the electrode assembly 100. For example, the first electrode tab may be welded to the first sub-plate 320. The first sub-plate 320 may be connected to the first electrode tab and may be electrically connected to the first electrode plate.

[0065] The first current collector 330 may be coupled to the first sub-plate 320. For example, the first current collector 330 and the first sub-plate 320 may be joined by welding. The first current collector 330 may be electrically connected to the first sub-plate 320.

[0066] The first current collector 330 may include a first planar portion 330_PL and a first protruding portion 330_PR. The first planar portion 330_PL may be bonded to the first sub-plate 320 by welding. The first protruding portion 330_PR may protrude from the first planar portion 330_PL. The first protruding portion 330_PR may have a cylindrical shape.

[0067] The first insulating member 340 may be located between the first sub-board assembly 310 and the first cap assembly 350. The first insulating member 340 may prevent the first sub-board 320 and the first cap plate 360 from contacting each other.

[0068] The first cap assembly 350 may include a first cap plate 360 , a first sealing member 370 , and a first terminal plate 380 .

[0069] The first sealing member 370 may be coupled to the first cap plate 360. The first sealing member 370 may include a first through hole TH1. The first sealing member 370 may provide a seal between the first terminal plate 380 and the first cap plate 360. The first sealing member 370 may include an insulating material that insulates the first cap plate 360 and the first terminal plate 380 from each other.

[0070] The first terminal plate 380 may be coupled to a surface of the first sealing member 370. The upper surface of the first terminal plate 380 may include a recess. For example, the recess may be formed in a portion of the upper surface of the first terminal plate 380 that overlaps the first protruding portion 330_PR in the first direction X. Due to the recess, the thickness of the central portion of the first terminal plate 380 may be less than the thickness of other portions of the first terminal plate 380.

[0071] The first terminal plate 380 may be a positive electrode terminal of the secondary battery. A bus bar may be welded to a surface of the first terminal plate 380 and may be electrically connected to another secondary battery.

[0072] In some embodiments, the first terminal plate 380 may include a first hole H1 provided in a recess of the first terminal plate 380. A portion of the upper surface of the first protruding portion 330_PR may be exposed through the first hole H1. When a portion of the upper surface of the first protruding portion 330_PR is exposed through the first hole H1, it can be determined whether the first terminal plate 380 and the first protruding portion 330_PR are in contact with each other. However, the present disclosure is not limited in this respect. For example, the first terminal plate 380 may not be provided with the first hole H1 so as to completely cover the upper surface of the first protruding portion 330_PR.

[0073] The first current collector 330 may be coupled to the first terminal plate 380. Specifically, the first protruding portion 330_PR may extend through the through-hole formed in the first sealing member 370 so as to contact the first terminal plate 380. The first protruding portion 330_PR and the first terminal plate 380 may be welded. For example, the first welding region (e.g., Figure 5 A first welding area WA1 (see FIG. 5 ) may be formed on the upper surface of the first terminal plate 380. A welding process may be performed on the first welding area WA1 to thereby join the first terminal plate 380 and the first current collector 330. Thus, the first current collector 330 and the first terminal plate 380 may be electrically connected. As a result of the welding process, a weld bead or the like may be formed in the first welding area WA1. The first welding area WA1 is shown as having a ring shape, but is not limited thereto. That is, the first welding area WA1 may have any shape by which the first terminal plate 380 and the first current collector 330 are joined by welding.

[0074] Figure 5 A first cover assembly according to some embodiments of the present disclosure is shown. For reference, Figure 5 Can be viewed in the first direction X Figure 2 Plan view of a secondary battery.

[0075] Reference Figure 5 , the first cover assembly 350 may include a first outer cover 390 .

[0076] The first cover plate 360 may include at least one open area (eg, Figure 8 360_OP in the first cover plate 360). The first outer cover 390 may be located in the first open area 360_OP of the first cover plate 360 and may be coupled to the first cover plate 360. For example, the first cover plate 360 and the first outer cover 390 may be welded along the first open area 360_OP of the first cover plate 360. As a result, a second weld area WL1 may be formed along the first open area 360_OP of the first cover plate 360. The second weld area WL1 may include a weld bead, etc.

[0077] In some embodiments, the electrolyte inlet 130 may be disposed on at least one of the first outer covers 390 , but the present disclosure is not limited in this regard. For example, the electrolyte inlet 130 may be disposed on the first cover plate 360 .

[0078] Figure 6 Shown Shown Figure 2 Magnified view of region R2 in FIG.

[0079] Reference Figure 6, the second sub-plate assembly 410 and the second cap assembly 450 may be coupled to the second side of the electrode assembly 100. The second sub-plate assembly 410 may be coupled to the second side of the electrode assembly 100 and may be electrically connected to the second electrode plate (e.g., the negative electrode plate) of the electrode assembly 100. The second sub-plate assembly 410 may include a second sub-plate 420 and a second current collector 430.

[0080] The second sub-plate 420 may be coupled to the second electrode tab of the electrode assembly 100. For example, the second electrode tab may be welded to the second sub-plate 420. The second sub-plate 420 may be connected to the second electrode tab, and the second sub-plate 420 may be electrically connected to the second electrode plate.

[0081] The second current collector 430 may be coupled to the second sub-plate 420. For example, the second current collector 430 and the second sub-plate 420 may be joined by welding. The second current collector 430 may be electrically connected to the second sub-plate 420.

[0082] The second current collector 430 may include a second planar portion 430_PL and a second protruding portion 430_PR. The second planar portion 430_PL may be bonded to the second sub-plate 420 by welding. The second protruding portion 430_PR may protrude from the second planar portion 430_PL. The second protruding portion 430_PR may have a cylindrical shape.

[0083] The second insulating member 440 may be located between the second sub-board assembly 410 and the second cap assembly 450. The second insulating member 440 may prevent the second sub-board 420 and the second cap plate 460 from contacting each other.

[0084] The second cap assembly 450 may include a second cap plate 460 , a second sealing member 470 , and a second terminal plate 480 .

[0085] The second sealing member 470 may be coupled to the second cap plate 460. A through hole may be formed in the second sealing member 470. The second sealing member 470 may provide a seal between the second terminal plate 480 and the second cap plate 460. The second sealing member 470 may include an insulating material. The second sealing member 470 may insulate the second cap plate 460 and the second terminal plate 480 from each other.

[0086] The second terminal plate 480 may be coupled to the surface of the second sealing member 470. The second terminal plate 480 may be a negative electrode terminal of the secondary battery. A bus bar may be welded to the surface of the second terminal plate 480 and may be electrically connected to another secondary battery. For example, the bus bar may be welded to the upper terminal plate 480_UT.

[0087] The second terminal plate 480 may include an upper terminal plate 480_UT and a lower terminal plate 480_LT. The lower terminal plate 480_LT may contact the second sealing member 470. The upper terminal plate 480_UT may be located on top of the lower terminal plate 480_LT. For example, the lower terminal plate 480_LT may be located between the second sealing member 470 and the upper terminal plate 480_UT.

[0088] The upper surface of the second terminal plate 480 may include a recess. A portion of the lower terminal plate 480_LT may be exposed through the upper terminal plate 480_UT. For example, a portion of the lower terminal plate 480_LT may be exposed through the recess in the center portion of the upper terminal plate 480_UT. The recess of the upper terminal plate 480_UT may overlap with the second protruding portion 430_PR in the first direction X. The recess of the upper terminal plate 480_UT may overlap with the second protruding portion 430_PR. Figure 4 The recesses of the first terminal plates 380 have the same shape.

[0089] In some embodiments, the upper terminal plate 480_UT and the lower terminal plate 480_LT can be formed of different materials. The upper terminal plate 480_UT can include, for example, aluminum (Al). The lower terminal plate 480_LT can include, for example, copper (Cu). Specifically, the upper terminal plate 480_UT can be a conductive material including Al as a main component. The lower terminal plate 480_LT can be a conductive material including Cu as a main component. As used herein, in the language of ordinary skill in the art, the term "main component" refers to the main content material in the material of the alloy.

[0090] Although the upper terminal plate 480_UT has been described as including Al and the lower terminal plate 480_LT has been described as including Cu, these descriptions are merely illustrative. In some embodiments, the upper terminal plate 480_UT and the lower terminal plate 480_LT may include other conductive metals.

[0091] In some embodiments, the lower terminal plate 480_LT may include a second hole H2. The second hole H2 may be formed so that the second protrusion 430_PR is exposed through the lower terminal plate 480_LT. That is, a portion of the upper surface of the second protrusion 430_PR may be exposed through the second hole H2. However, the present disclosure is not limited in this respect. For example, the second terminal plate 480 may not include the second hole H2, and therefore, the second terminal plate 480 may completely cover the upper surface of the second protrusion 430_PR.

[0092] The second current collector 430 may be coupled to the second terminal plate 480. Specifically, the second protruding portion 430_PR may extend through the through hole formed in the second sealing member 470 so as to contact the lower terminal plate 480_LT. The second protruding portion 430_PR and the second terminal plate 480 may be welded. For example, the third welding region (e.g., Figure 7 A third welding area WA2 may be formed on the upper surface of the lower terminal plate 480_LT. A welding process may be performed in the third welding area WA2 to join the second terminal plate 480 and the second current collector 430. Thus, the second current collector 430 and the second terminal plate 480 may be electrically connected. As a result of the welding process, a weld bead, etc., may be formed in the third welding area WA2. The third welding area WA2 is shown as having a ring shape, but is not limited in this respect. The third welding area WA2 may have any shape by which the second terminal plate 480 and the second current collector 430 are joined by welding.

[0093] Figure 7 A second cover assembly according to some embodiments of the present disclosure is shown. For reference, Figure 7 Can be viewed in the first direction X Figure 2 Plan view of a secondary battery.

[0094] Reference Figure 7 , the second cover assembly 450 may further include a second outer cover 490 .

[0095] The second cover plate 460 may include one or more second open areas. The second open areas of the second cover plate 460 may have the same shape as the first open area 360_OP of the first cover plate 360. The second outer cover 490 may be located in the second open areas of the second cover plate 460 and may be coupled to the second cover plate 460. For example, the second cover plate 460 and the second outer cover 490 may be welded along the second open areas of the second cover plate 460. As a result, a fourth weld area WL2 may be formed along the second open areas of the second cover plate 460. The fourth weld area WL2 may include a weld bead, etc.

[0096] Figure 8 A perspective view of a cover-subplate assembly according to some embodiments of the present disclosure is shown.

[0097] Reference Figure 8 , the first cover-sub-plate assembly 300 according to some embodiments of the present disclosure may include a first sub-plate assembly 310 and a first cover assembly 350 .

[0098] The first cover-subplate assembly 300 can be used as shown in FIG. Figure 1 and Figure 2In the secondary battery described above, the first sub-plate assembly 310 may include a first sub-plate 320 and a first current collector 330. The first sub-plate assembly 310 may be the same as that described above. Figure 4 Same as described.

[0099] The first cap assembly 350 may include a first cap plate 360, a first sealing member 370, and a first terminal plate 380. The first sealing member 370 and the first terminal plate 380 may be the same as those described above. Figure 4 Hereinafter, the first cover plate 360 and the first open area 360_OP will be described.

[0100] The first cover plate 360 may include one or more open areas 360_OP. A portion of the first sub-plate 320 may be exposed through each of the first open areas 360_OP. For example, when the first cover plate 360 is attached to Figure 3 When the first side 210 of the housing 200 is in the center, the first sub-board 320 may be exposed through the first open area 360_OP.

[0101] In some embodiments, Figure 5 The first outer cover 390 may be coupled to the first open region 360_OP. Specifically, the first outer cover 390 may be coupled to the first open region 360_OP to seal the secondary battery.

[0102] The first open areas 360_OP are shown as two first open areas provided on opposite sides of the first terminal plate 380, but are not limited to such a configuration. Contrary to what is shown, the first open areas 360_OP may be placed in various positions and provided in different numbers.

[0103] A secondary battery can be manufactured by combining an electrode assembly with a current collector, and then combining the current collector with a terminal plate. In such a secondary battery manufacturing process, defects may occur in the weld joint when the current collector and the terminal plate do not fit tightly together. In addition, when the electrode assembly is combined with the current collector and the cover plate is attached to the surface of the housing, it may be impossible to determine whether the terminal plate and the current collector fit tightly together. Moreover, when the current collector and the terminal plate do not fit tightly together or are misaligned, the electrical characteristics of the secondary battery may deteriorate.

[0104] The first cover-sub-plate assembly 300 according to some embodiments of the present disclosure may include a first cover assembly 350 and a first sub-plate assembly 310. Specifically, the first sub-plate assembly 310 and the first cover assembly 350 may be arranged in a combined state. Before the first cover-sub-plate assembly 300 is coupled to the housing 200, the first current collector 330 and the first terminal plate 380 may be joined by welding. As a result, it can be determined whether the first current collector 330 and the first terminal plate 380 are tightly fitted and aligned after the welding process. Therefore, the defect rate of the secondary battery can be reduced, and the reliability of the secondary battery can be improved.

[0105] When the manufacturing process causes the current collector and terminal plate to not fit tightly or be misaligned, this defect can be detected during a later testing phase. That is, the defect can be detected after significant steps in the secondary battery manufacturing process have already been performed. Consequently, this can increase the manufacturing cost of the secondary battery.

[0106] When using the first cover-subplate assembly 300 according to some embodiments of the present disclosure, the manufacturing process can be simplified and manufacturing costs can be reduced. If there is a problem with the bonding between the first current collector 330 and the first terminal plate 380, the secondary battery manufacturing process can be continued by replacing the first cover-subplate assembly 300 with another one. Therefore, the components used to manufacture the secondary battery can be easily managed, the difficulty of the manufacturing process can be reduced, and the manufacturing costs can be reduced.

[0107] Figures 9 to 12 A method of manufacturing a secondary battery according to some embodiments of the present disclosure is shown.

[0108] Reference Figure 9 , the electrode assembly 100 may be inserted into the case 200. The electrode assembly 100 may extend through the first side 210 (or the second side 220) of the case 200 to be inserted into the case 200 in the first direction X.

[0109] Reference Figure 10 , the first cover-sub-plate assembly 300 and the second cover-sub-plate assembly 400 can be coupled to opposite sides of the housing 200. Specifically, the first cover plate 360 can be welded to the first end of the housing 200, and the second cover plate 460 can be welded to the second end of the housing 200. However, the present disclosure is not limited in this respect. The order of welding the first cover plate 360 and the second cover plate 460 can be reversed, and the welding of the first cover plate 360 and the second cover plate 460 can be performed substantially simultaneously.

[0110] In some embodiments, the first terminal plate 380 and the first current collector 330 may be joined by welding, and the second terminal plate 480 and the second current collector 430 may be joined by welding. As described above, the first cover plate 360 and the housing 200 are joined by welding, and the first terminal plate 380 is welded to the first current collector 330, but the present disclosure is not limited in this regard. Figure 8 As shown in FIG, in some embodiments, the first cover-subplate assembly 300 may be provided by welding the first terminal plate 380 and the first current collector 330 .

[0111] Reference Figure 11 The first sub-plate 320 and the electrode assembly 100 may be joined by welding. Specifically, a welding process may be performed on the first sub-plate 320 exposed by the first open region 360_OP, so that the first sub-plate 320 and the first electrode tab of the electrode assembly 100 are joined by welding. As a result, a fifth welding region SWL may be formed on the first sub-plate 320. The fifth welding region SWL may include a weld bead, etc.

[0112] For ease of description, the first sub-plate 320 and the electrode assembly 100 are illustrated, but the second sub-plate 420 and the electrode assembly 100 may be combined in the same manner.

[0113] Reference Figure 12 , the first outer cover 390 can be joined to the first open area 360_OP by welding. The first outer cover 390 can be located in the first open area 360_OP and secured by the welded joint. As a result, the housing 200 can be sealed. For ease of description, the first open area 360_OP and the first outer cover 390 are shown, but the second outer cover 490 can be joined to the second open area of the second cover plate in the same manner.

[0114] Figure 13 A flowchart illustrating a method of manufacturing a secondary battery 1300 according to some embodiments of the present disclosure is shown.

[0115] Reference Figure 13 In step S1310, a cover-sub-plate assembly including a cover assembly and a sub-plate assembly may be prepared. In some embodiments, the cover-sub-plate assembly including the cover assembly and the sub-plate assembly is joined by welding. However, the cover-sub-plate assembly is not limited in this respect. The cover-sub-plate assembly may be provided when the cover assembly and the sub-plate assembly are separate.

[0116] In step S1320, the electrode assembly can be inserted into the housing. The electrode assembly can be inserted into the open side of the housing. As described above, the cover-sub-plate assembly is prepared and the electrode assembly is inserted into the housing, but the present disclosure is not limited to such a process. For example, the electrode assembly can be inserted into the housing and the cover-sub-plate assembly can be prepared.

[0117] In step S1330, the cover-subplate assembly can be joined to the first end of the housing. Specifically, the cover plate of the cover-subplate assembly can be welded to the first side of the housing. If the cover assembly and subplate assembly are provided separately, the cover assembly and subplate assembly can be welded together. Alternatively, the cover-subplate assembly can be joined to the second end of the housing in the same or similar manner.

[0118] In step S1340, the sub-plate may be bonded to the electrode assembly by welding. Specifically, the sub-plate exposed through the open area of the cap plate may be bonded to the electrode tab of the electrode assembly by welding.

[0119] In step S1350, the outer cover may be joined to the open area of the cap assembly by welding. By joining the outer cover to the open area of the cap plate by welding, a secondary battery may be manufactured.

[0120] Although the present disclosure has been described above with respect to the embodiments of the present disclosure, the present disclosure is not limited thereto, and various modifications and variations may be made by those skilled in the art within the spirit of the present disclosure and the equivalent scope of the appended claims.

[0121] <Description of Reference Signs> 100: Electrode assembly 200: Shell 310: First daughter board assembly 320: First daughter board 330: First current collector 340: First insulating member 350: First cover assembly 360: First cover plate 360_OP: First open area 370: First sealing member 380: First terminal plate 390: First outer cover 410: Second daughter board assembly 420: Second daughter board 430: Second current collector 440: Second insulating member 450: Second cover assembly 460: Second cover plate 470: Second sealing member 480: Second terminal plate 490: Second outer cover.

Claims

1. A secondary battery, comprising: electrode assembly; a sub-plate assembly comprising a sub-plate connected to the electrode assembly and a current collector bonded to a surface of the sub-plate; as well as a cover assembly, coupled to the daughterboard assembly, The cover assembly includes a cover plate, and at least one open area is formed in the cover plate so that a portion of the sub-plate is not covered by the cover plate.

2. The secondary battery according to claim 1, wherein The cap assembly further includes a terminal plate coupled to the cap plate, and Wherein, the terminal plate is connected to the current collector.

3. The secondary battery according to claim 2, wherein The current collector includes a planar portion and a convex portion, and Wherein, the protruding portion is connected to the terminal plate.

4. The secondary battery according to claim 3, wherein The upper surface of the terminal plate includes an area welded to the protruding portion.

5. The secondary battery according to claim 1, wherein The sub-plate and the electrode assembly are fixed via welding through the at least one open area, thereby forming a welding area on the sub-plate. 6 . The secondary battery according to claim 1 , further comprising at least one outer cover positioned in the at least one open region formed in the cap plate.

7. The secondary battery according to claim 1, wherein The cover plate includes a weld region welded along the at least one open region.

8. The secondary battery according to claim 1, further comprising a case accommodating the electrode assembly, in, The housing is fixed to the cover plate by welding.

9. The secondary battery according to claim 1, further comprising a case accommodating the electrode assembly, the case comprising an open first side and an open second side opposite to the first side, in, The cap plate covers at least one of the first side and the second side, the cap assembly includes a terminal plate coupled to the cap plate, and a sealing member is located between the cap plate and the terminal plate.

10. The secondary battery according to claim 9, wherein The housing comprises: a first long side wall and a second long side wall facing each other and spaced apart from each other; and a first short side wall and a second short side wall facing each other and spaced apart from each other, The areas of the first short sidewall and the second short sidewall are smaller than the areas of the first long sidewall and the second long sidewall.

11. The secondary battery according to claim 1, wherein The cap assembly further includes a terminal plate coupled to the cap plate, Wherein, the terminal plate includes an upper terminal plate and a lower terminal plate, and Wherein, the upper terminal plate and the lower terminal plate are formed of different materials.

12. A cover-sub-plate assembly, comprising: a daughter plate assembly comprising a daughter plate and a current collector coupled to the daughter plate; as well as a cover assembly, coupled to the daughterboard assembly, The cover assembly includes: a cover plate, and at least one open area is formed in the cover plate so that a portion of the sub-plate is not covered by the cover plate; a terminal plate coupled to the cover plate; and a sealing member located between the cover plate and the terminal plate.

13. The cover-subplate assembly according to claim 12, wherein: The current collector includes a planar portion and a convex portion, and Wherein, the protruding portion is connected to the terminal plate.

14. The cover-subplate assembly according to claim 13, wherein: The upper surface of the terminal plate includes an area welded to the protruding portion.

15. The cover-subplate assembly of claim 12, further comprising at least one outer cover positioned in the at least one open area formed in the cover plate.

16. A method for manufacturing a secondary battery, the method comprising the following steps: preparing a cap-subplate assembly including a cap assembly and a subplate assembly, the subplate assembly including a subplate and a current collector coupled to the subplate; inserting the electrode assembly into the housing; coupling the cover-subplate assembly to an end portion of the housing; and welding the sub-plate to the electrode assembly, At least one open area is formed in the cover assembly such that a portion of the sub-board is not covered by the cover assembly.

17. The method according to claim 16, wherein: The cover assembly includes a cover plate, and The step of coupling the cover-subplate assembly to the end portion of the housing includes joining the end portion of the housing and the cover plate by welding.

18. The method according to claim 16, wherein The step of welding the sub-plate to the electrode assembly includes welding the sub-plate exposed through the at least one open area and the electrode assembly.

19. The method of claim 16, further comprising positioning an outer cover to the at least one open area of the cover assembly and welding the outer cover to the cover assembly.

20. The method according to claim 16, wherein The steps of preparing the cover-subplate assembly include: forming the cover assembly by combining a cover plate and a terminal plate; forming the daughter plate assembly by combining the daughter plate and the current collector; and The terminal plate and the current collector are welded.

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