Secondary batteries and methods for manufacturing secondary batteries

Abstract

A secondary battery and a method of manufacturing a secondary battery are disclosed. The secondary battery includes: an electrode assembly including a first electrode, a second electrode, and a separator between the first electrode and the second electrode; a housing including a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly; a terminal plate that closes a first opening formed at the center of the cover portion and is electrically connected to the first electrode; and a bottom plate that closes a second opening formed on the other side of the sidewall portion and is electrically connected to the second electrode, wherein the first electrode includes at least one first substrate terminal block electrically connected to the terminal plate, and wherein the second electrode includes at least one second substrate terminal block electrically connected to the bottom plate.

Description

Technical Field

[0001] Some aspects of embodiments of this disclosure relate to a secondary battery and a method of manufacturing a secondary battery. Background Technology

[0002] Unlike primary batteries, which are not designed for (re)charging, secondary (or rechargeable) batteries are designed to be discharged and recharged without damaging the battery. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources for driving motors in hybrid and electric vehicles, as well as for storing electricity (e.g., household and / or utility-scale power storage). A secondary battery typically includes an electrode assembly containing positive and negative electrodes, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] Recently, wearable devices using Bluetooth technology, such as wireless headphones and smartwatches, have been making continuous technological advancements. Consequently, consumer demand for ultra-compact rechargeable batteries is increasing, depending on the usage environment. Rechargeable batteries such as coin cell batteries are one example.

[0004] In the case of ultra-compact secondary batteries, as their absolute size decreases, technologies for effectively increasing energy density may be desired. In particular, technologies that minimize empty space within the battery cell and fill the internal space with high density can be utilized.

[0005] The information disclosed in this background section is only intended to enhance the understanding of the background art, and therefore the information discussed in this background section does not necessarily constitute prior art. Summary of the Invention

[0006] Some aspects of embodiments of this disclosure include a secondary battery that solves the above-mentioned problems and a method for manufacturing a secondary battery.

[0007] These and other aspects and features of embodiments of this disclosure will be described in or will become apparent from the following description of embodiments of this disclosure.

[0008] According to some embodiments of this disclosure, a secondary battery includes: an electrode assembly including a first electrode, a second electrode, and a separator between the first electrode and the second electrode; a housing including a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly; a terminal plate that closes a first opening formed at the center of the cover portion and is electrically connected to the first electrode; and a bottom plate that closes a second opening formed on the other side of the sidewall portion and is electrically connected to the second electrode, wherein the first electrode includes at least one first substrate terminal block electrically connected to the terminal plate, and wherein the second electrode includes at least one second substrate terminal block electrically connected to the bottom plate.

[0009] According to some embodiments, the first electrode may further include a first coated portion and a first uncoated portion provided at both ends of the first coated portion, wherein a first active material layer is located on a first substrate of the first electrode in the first coated portion, and no first active material layer is present in the first uncoated portion. The second electrode may further include a second coated portion and a second uncoated portion provided at both ends of the second coated portion, wherein a second active material layer is located on a second substrate of the second electrode in the second coated portion, and no second active material layer is present in the second uncoated portion. At least one first substrate tab protrudes from the first substrate of the first electrode toward a terminal plate, and at least one second substrate tab protrudes from the second substrate of the second electrode toward a base plate.

[0010] According to some embodiments, at least one first substrate terminal piece may include a first vertical portion extending in a vertical direction from a first coated portion and a first contact portion that bends from the first vertical portion and extends toward the center of the secondary battery, and wherein at least one second substrate terminal piece may include a second vertical portion extending in a vertical direction from a second coated portion and a second contact portion that bends from the second vertical portion and extends toward the center of the secondary battery.

[0011] According to some embodiments, at least one first substrate terminal piece is shorter in length in the winding direction of the electrode assembly than the length of the first coating portion in the winding direction, wherein at least one second substrate terminal piece is shorter in length in the winding direction than the length of the second coating portion in the winding direction.

[0012] According to some embodiments, the length of at least one first substrate terminal block in the winding direction is shorter than the length of at least one second substrate terminal block in the winding direction.

[0013] According to some embodiments, the terminal block overlaps with at least one first substrate terminal piece in the vertical direction, and wherein the at least one first substrate terminal piece is located inside the terminal block in the horizontal direction.

[0014] According to some embodiments, at least one first substrate terminal piece extends closer to the terminal plate in the vertical direction than to the diaphragm, and wherein at least one second substrate terminal piece extends closer to the base plate in the vertical direction than to the diaphragm.

[0015] According to some embodiments, the secondary battery further includes an insulator between the cover portion and the terminal plate, which insulates the cover portion and the terminal plate.

[0016] According to some embodiments, the terminal block may include a protrusion inserted into a first opening and a flange portion below the protrusion, wherein the flange portion is between the electrode assembly and the cover portion.

[0017] According to some embodiments, at least one first substrate terminal block is soldered to a terminal board, and at least one second substrate terminal block is soldered to a base plate.

[0018] According to some embodiments, the base plate and housing may comprise stainless steel (SUS), and the terminal plate may comprise aluminum (Al).

[0019] According to some embodiments, the outer portion of the electrode assembly contacts the sidewall portion.

[0020] According to some embodiments, the sidewall portion and the cover portion are integrally formed.

[0021] According to some embodiments of the present disclosure, in a method of manufacturing a secondary battery, the method includes: forming an electrode assembly including a first electrode, a separator, and a second electrode; electrically connecting the first electrode of the electrode assembly to a terminal plate; inserting the electrode assembly and the terminal plate into a housing including a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly; and connecting a bottom plate to an opening formed on the other side of the sidewall portion and electrically connecting the second electrode to the bottom plate, wherein the first electrode includes at least one first substrate terminal block electrically connected to the terminal plate, and wherein the second electrode includes at least one second substrate terminal block electrically connected to the bottom plate.

[0022] According to some embodiments, forming an electrode assembly may include forming at least one first substrate tab, wherein forming at least one first substrate tab may include removing a first portion from a region of the first substrate of the first electrode where a first active material layer is not present and leaving a second portion, and cutting the second portion at regular intervals to form at least one first substrate tab.

[0023] According to some embodiments, forming an electrode assembly may include forming at least one second substrate tab, wherein forming at least one second substrate tab may include removing a first portion from a region of the second substrate of the second electrode where a second active material layer is not present and leaving a second portion, and cutting the second portion at regular intervals to form at least one second substrate tab.

[0024] According to some embodiments, electrically connecting the first electrode to the terminal block may include: bending at least one first substrate tab, and soldering the bent at least one first substrate tab to the terminal block.

[0025] According to some embodiments, electrically connecting the second electrode to the base plate may include: bending at least one second substrate terminal piece; welding the bent at least one second substrate terminal piece to the base plate; and welding the base plate to a sidewall portion.

[0026] According to some embodiments, inserting the electrode assembly and terminal block into the housing may include arranging the electrode assembly such that the outer portion of the electrode assembly is in close contact with the sidewall portion.

[0027] According to some embodiments, inserting the electrode assembly and terminal plate into the housing may include arranging an insulator between the cover portion and the terminal plate, and applying heat to the cover portion and the terminal plate to close a first opening formed at the center of the cover portion.

[0028] Some embodiments of this disclosure may provide a tabless structure in which electrode tabs are not connected to electrode assemblies, thereby increasing the energy density of the secondary battery.

[0029] According to some embodiments of this disclosure, because the electrode assembly has a structure in which electrode tabs and cover strips are removed, the electrode assembly can be inserted into the secondary battery casing in close contact.

[0030] According to some embodiments of this disclosure, an expanded coating area can be ensured by removing the electrode tabs and cover strips from the electrode plate.

[0031] According to some embodiments of this disclosure, the capacity of the secondary battery can be increased because a larger coated area is ensured.

[0032] According to some embodiments of this disclosure, since the internal space of the secondary battery is effectively utilized, the amount of electrolyte that can be filled into the secondary battery can be increased, and the capacity of the individual cells of the secondary battery can be increased.

[0033] According to some embodiments of this disclosure, because the terminal block includes a flange portion extending into the secondary battery, the internal pressure resistance of the secondary battery can be increased, thereby ensuring the operational stability of the secondary battery.

[0034] However, the features and characteristics of the embodiments according to this disclosure are not limited to the foregoing, and those skilled in the art will clearly understand from the following detailed description other aspects and features not mentioned. Attached Figure Description

[0035] The following accompanying drawings illustrate aspects of some embodiments of this disclosure, and together with the detailed description of this disclosure, further describe aspects and features of embodiments according to this disclosure. Therefore, this disclosure should not be construed as limited to the drawings:

[0036] Figure 1 This is a schematic diagram illustrating a secondary battery according to some embodiments of the present disclosure.

[0037] Figure 2 An exploded view of a secondary battery according to some embodiments of the present disclosure is shown.

[0038] Figure 3 This is a cross-sectional view showing a secondary battery according to some embodiments of the present disclosure.

[0039] Figure 4 This illustrates some embodiments according to the present disclosure. Figure 3 A magnified view of part R.

[0040] Figure 5 Examples of terminal boards according to some embodiments of the present disclosure are shown.

[0041] Figure 6 An example of a first electrode prior to the formation of a first substrate tab is shown according to some embodiments of the present disclosure.

[0042] Figure 7 An example of a first electrode after the formation of a first substrate tab is shown according to some embodiments of the present disclosure.

[0043] Figure 8 An example of a second electrode prior to the formation of a second substrate tab is shown according to some embodiments of the present disclosure.

[0044] Figure 9 An example of a second electrode after the formation of a second substrate tab is shown according to some embodiments of the present disclosure.

[0045] Figure 10 Examples of secondary batteries before and after bending the first substrate tab are shown according to some embodiments of the present disclosure.

[0046] Figure 11 An example is shown in which a first substrate tab is electrically connected to a terminal block along the winding direction of an electrode assembly, according to some embodiments of the present disclosure.

[0047] Figure 12 Examples of secondary batteries before and after bending the second substrate tab are shown according to some embodiments of the present disclosure.

[0048] Figure 13 An example is shown in which a second substrate terminal block is electrically connected to the base plate along the winding direction of the electrode assembly, according to some embodiments of the present disclosure.

[0049] Figure 14 Examples are shown where the base plate and the side wall portions of the housing are electrically connected by welding according to some embodiments of the present disclosure.

[0050] Figure 15 This is a diagram showing the state in which the electrode assembly is housed in the housing, viewed from a vertical direction.

[0051] Figure 16 This is a flowchart illustrating an example of a method for manufacturing a secondary battery according to some embodiments of the present disclosure.

[0052] Explanation of reference numerals in the attached figures

[0053] 10: Secondary batteries

[0054] 120: Shell

[0055] 140: Insulator

[0056] 160: Terminal block

[0057] 180: Base Plate

[0058] 200: Electrode assembly

[0059] 210: First substrate connector

[0060] 220: Second substrate connector Detailed Implementation

[0061] In the following description, aspects of some embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as having their usual or dictionary meaning, and should be interpreted in a way consistent with the technical spirit of the present disclosure, based on the principle that the inventor can be his / her own lexicographer to appropriately define the concepts of the terms in order to best describe his / her invention.

[0062] The embodiments described in this specification and the configurations shown in the accompanying drawings are merely some embodiments of this disclosure and do not represent all the technical spirit, aspects, and features of this disclosure. Therefore, it should be understood that various equivalents and modifications may exist that can replace or modify the embodiments described herein at the time of filing this application.

[0063] It will be understood that when an element or layer is described as being "on," "connected to," or "attached to" another element or layer, it can be directly on, connected to, or attached to the other element or layer, or one or more intermediary elements or layers may be present. When an element or layer is described as being "directly on," "directly connected to," or "directly attached to" another element or layer, no intermediary element or layer is present. For example, when a first element is described as being "attached" or "connected" to a second element, the first element can be directly attached to or connected to the second element, or the first element can be indirectly attached to or connected to the second element via one or more intermediary elements.

[0064] In the accompanying drawings, the dimensions of various elements, layers, etc., may be enlarged for clarity of illustration. The same reference numerals indicate the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Furthermore, the use of "may" in describing embodiments of this disclosure refers to "one or more embodiments of this disclosure." Expressions such as "at least one of..." and "any one of..." preceding / following the list of elements modify the entire list of elements, but not individual elements in the list. When phrases 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 A, B, and C" are used to specify a list of elements A, B, and C, the phrase may 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 terms "use" and "be used" may be considered synonymous with the terms "utilize" and "be exploited." As used herein, the terms “substantially,” “about,” and similar terms are used as approximations rather than terms of degree and are intended to take into account the inherent variations in measurements or calculations that would be apparent to a person skilled in the art.

[0065] 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 segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or segment from another element, component, region, layer, or segment. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment.

[0066] For ease of description, this document may use spatial relative terms such as “below,” “under,” “down,” “above,” “up,” etc., to describe the relationship between one element or feature and another element or feature as shown in the figures. It will be understood that spatial relative terms are intended to include 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 flipped, an element described as “below” or “under” other elements or features will be oriented as “above” or “upon” other elements or features. Therefore, the term “below” can include both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein should be interpreted accordingly.

[0067] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure. As used herein, the singular form “a” is intended to include the plural form as well, unless the context clearly indicates otherwise. It will be further understood that, when used in this specification, the term “comprising” specifies the presence of the stated feature, integer, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0068] Furthermore, any numerical ranges disclosed and / or enumerated herein are intended to include all subranges with the same numerical precision included within the enumerated ranges. For example, the range “1.0 to 10.0” is intended to include all subranges between the enumerated minimum value of 1.0 and the enumerated maximum value of 10.0 (and includes both the enumerated minimum value of 1.0 and the enumerated maximum value of 10.0), i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit enumerated herein is intended to include all lower numerical limits included therein, and any minimum numerical limit enumerated herein is intended to include all higher numerical limits included therein. Therefore, the applicant reserves the right to amend this specification, including the claims, to expressly enumerate any subranges included within the scope expressly enumerated herein.

[0069] Referring to two compared elements, features, etc., as “identical” may mean that they are “substantially identical.” Therefore, the phrase “substantially identical” can include cases with deviations considered low in the art, such as less than 5%. Furthermore, when a parameter is said to be consistent in a given region, this may mean that it is consistent in terms of average value.

[0070] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0071] Placing any element "above (or below)" or "on (below)" another element can mean that the arbitrary element can be positioned to contact the upper (or lower) surface of the element, and the other element can also be located between the element and any element located above (or below) the element.

[0072] Additionally, it will be understood that when a component is referred to as “connected,” “linked,” or “attached” to another component, the components can be directly “connected,” “linked,” or “attached” to each other, or another component can be “between” the components.

[0073] Throughout this specification, unless otherwise stated, when “A and / or B” is used, it means A, B, or A and B. In other words, “and / or” includes any or all combinations of the listed items. Unless otherwise indicated, when “C~D” is used, it means C and below D.

[0074] According to some embodiments, the secondary battery may be a coin-type battery (coin cell) or a button cell; however, this disclosure is not limited thereto, and may instead be a cylindrical or pin-type battery.

[0075] Coin-type or button-type batteries are typically thin, coin-shaped or button-shaped batteries with a height-to-diameter ratio (H / D) of less than 1, although this ratio is not strictly limited to this value. Because these batteries are typically cylindrical, their horizontal cross-section is usually circular; however, the term also includes variations where the horizontal cross-section is elliptical or polygonal. Here, "diameter" refers to the maximum distance the battery can be measured horizontally, and "height" refers to the maximum distance the battery can be measured vertically (i.e., the distance from the flat bottom surface to the flat top surface).

[0076] Figure 1 This is a schematic diagram illustrating a secondary battery 10 according to some embodiments of the present disclosure. Figure 2 An exploded view of a secondary battery according to some embodiments of the present disclosure is shown. Figure 3 This is a cross-sectional view showing a secondary battery according to some embodiments of the present disclosure.

[0077] exist Figures 1 to 3 The diagram illustrates the structure and sub-configuration of a secondary battery 10 according to some embodiments of the present invention. Figure 3The secondary battery 10 includes: a housing 120; an electrode assembly 200 inserted into the housing 120; at least one first substrate terminal piece 210 included in the electrode assembly 200 and electrically connected to a terminal plate 160; at least one second substrate terminal piece 220 included in the electrode assembly 200 and electrically connected to a base plate 180; a terminal plate 160; and a base plate 180. Additionally, the secondary battery 10 may also include an insulator 140 for insulating the housing 120 from the terminal plate 160. Figure 3 It is along Figure 2 A cross-sectional view of the secondary battery 10 taken along the imaginary lines c1-c2. Figure 1 To the lower left, for understanding purposes, virtual direction references are shown: a first direction (X direction), a second direction perpendicular to the first direction (Z direction), and a third direction perpendicular to both the first and second directions (Y direction).

[0078] According to some embodiments of this disclosure, the housing 120 may include: a sidewall portion 122 surrounding a side surface of the electrode assembly 200; and a cover portion 121 extending horizontally from one side of the sidewall portion 122 and located on the electrode assembly 200. The cover portion 121 may include a first opening that may receive a terminal plate 160 or an insulator 140, thereby completing the shape of the secondary battery 10. Although the first opening may be formed at the center of the cover portion 121, it is not limited thereto and may be displaced from the center to another location. For example, the first opening may be offset to the left from the center of the cover portion 121 by a certain distance (e.g., a set or predetermined distance). According to some embodiments, the sidewall portion 122 may surround a side surface of the electrode assembly 200 and form an outer portion of the secondary battery 10. The sidewall portion 122 may be integrally formed with the cover portion 121. Thus, unlike an alternative cover assembly, the secondary battery 10 may have an integrated upper housing structure. However, the sidewall portion 122 and the cover portion 121 may also be formed separately and then connected to each other. Moreover, the sidewall portion 122 may also have Figure 1 Shapes other than cylindrical structures, such as those with curved cross-sections. Although Figure 1 The housing 120 is shown to have a cylindrical shape for the secondary battery 10, but the shape of the secondary battery 10 is not limited to this and can be prism or pouch-shaped.

[0079] Electrode assembly 200 according to some embodiments of this disclosure may include a first electrode 230, a second electrode 240, and a separator 250 between the first electrode 230 and the second electrode 240. The first electrode 230, the second electrode 240, and the separator 250 are wound to form a core structure housed in a housing 120. Additionally, to insulate the housing 120 from the core, the electrode assembly 200 may also include an insulating layer on its surface. The outer portion of the electrode assembly 200 may be positioned in close contact with a sidewall portion 122 of the housing 120 (e.g., contacting the sidewall portion 122 of the housing 120), which increases the amount of electrolyte that can be charged into the secondary battery 10, thereby increasing the single-cell capacity of the secondary battery 10.

[0080] According to some embodiments, the first electrode 230 of the electrode assembly 200 can be used as a positive electrode. The first electrode 230 may include: a first substrate made of a metal such as aluminum (Al); a first coated portion wherein a first active material layer (e.g., a transition metal oxide) is located on the first substrate; and a first uncoated portion provided at both ends of the first coated portion wherein the first active material layer is absent. Furthermore, the first electrode 230 may include at least one first substrate tab 210 electrically connected to the terminal block 160. Reference is made below. Figure 6 and Figure 7 A detailed description of the substructure of the first electrode, excluding the first substrate tab, is provided.

[0081] According to some embodiments, the second electrode 240 of the electrode assembly 200 can be used as a negative electrode. The second electrode 240 may include: a second substrate made of a metal such as copper (Cu) or nickel (Ni); a second coated portion wherein a second active material layer (e.g., graphite) is located on the second substrate; and a second uncoated portion provided at both ends of the second coated portion wherein the second active material layer is absent. Furthermore, the second electrode 240 may include at least one second substrate tab 220 electrically connected to the base plate 180. Reference is made below. Figure 8 and Figure 9 A detailed description of the substructure of the second electrode, excluding the second substrate terminal block, is provided.

[0082] According to some embodiments of this disclosure, the first substrate tab 210 can extend outward from the first substrate of the first electrode 230 and protrude toward the terminal plate 160, and electrically connect the first electrode 230 and the terminal plate 160. For example, the first substrate tab 210 can be connected to the terminal plate 160 by soldering, but is not limited to soldering, and can utilize any other suitable connection technology. In this way, the secondary battery 10 can adopt a tabless structure in which no additional electrode tabs are provided, allowing the electrode assembly 200 to be inserted into close contact with the housing 120, and ensuring an enlarged coating area, thereby increasing battery capacity.

[0083] According to some embodiments of this disclosure, the second substrate terminal piece 220 can extend outward from the second substrate of the second electrode 240 and protrude toward the base plate 180, thereby electrically connecting the second electrode 240 and the base plate 180. For example, the second substrate terminal piece 220 can be soldered to the base plate 180, but is not limited to soldering. Therefore, the second substrate terminal piece 220 can have a structure that protrudes in the opposite direction to the first substrate terminal piece 210. Thus, the same effect as the first substrate terminal piece 210 described above can be achieved, increasing the capacity of the secondary battery.

[0084] refer to Figure 2 and Figure 3 The first substrate terminal piece 210 and the second substrate terminal piece 220 of the electrode assembly 200 may have a curved structure toward the center of the secondary battery 10 and may be electrically connected to the terminal plate 160 and the base plate 180, respectively. However, the shapes of the first substrate terminal piece 210 and the second substrate terminal piece 220 are not limited thereto. For example, the first substrate terminal piece 210 and the second substrate terminal piece 220 may extend vertically from the first substrate or the second substrate without bending and be connected to the terminal plate 160 or the base plate 180. (See below for reference...) Figure 4 The structure and features of the first substrate connector and the second substrate connector are described in detail.

[0085] refer to Figure 2 and Figure 3 According to some embodiments, the length of the first substrate terminal piece 210 in the winding direction of the electrode assembly 200 may be shorter than the length of the second substrate terminal piece 220 in the winding direction. This is due to the structure of the terminal plate 160, which is part of the internal structure of the secondary battery 10, preventing or reducing direct contact between the terminal plate 160 and the housing 120. However, Figure 3 The arrangement shown is merely illustrative, and the length of the first substrate terminal 210 in the winding direction may be greater toward the center of the electrode assembly 200 or toward its edge. In another example, the length of the second substrate terminal 220 in the winding direction may be greater than... Figure 3 The length shown is short.

[0086] According to some embodiments, the terminal plate 160 may overlap with the first substrate tab 210 in a vertical direction (which may be a second direction). Therefore, when the first electrode 230 and the terminal plate 160 are electrically connected, the first substrate tab 210 and the terminal plate 160 can be electrically connected (e.g., soldered) from the upper portion of the terminal plate 160 in the vertical direction in the winding direction of the electrode assembly 200.

[0087] According to some embodiments, the first substrate terminal piece 210 may be located horizontally inside the terminal plate 160. (See reference...) Figure 3 Both ends of the terminal block 160 protrude outwards in the third direction (Y direction) beyond the first substrate connector 210. Therefore, it prevents the first substrate connector 210 from contacting external terminals or the housing 120 and causing an internal short circuit. However, the arrangement is not limited to this. Figure 3 Furthermore, the first substrate tab 210 may be located on the outside relative to the protrusions at both ends of the terminal plate 160. In this case, in order to prevent or reduce short circuits caused by the outwardly protruding tab, an external insulating layer or the like may be further included in the electrode assembly 200.

[0088] According to some embodiments, in the vertical direction, the first substrate terminal piece 210 may extend closer to the terminal plate 160 than to the diaphragm 250. Therefore, the first substrate terminal piece 210 can be electrically connected to the terminal plate 160. Similarly, according to some embodiments, the second substrate terminal piece 220 may extend in the vertical direction closer to the base plate 180 than to the diaphragm 250. Similar to the first substrate terminal piece 210, the second substrate terminal piece 220 can therefore be electrically connected to the base plate 180.

[0089] According to some embodiments of this disclosure, terminal plate 160 closes the first opening formed in cover portion 121 and is electrically connected to the first electrode 230. Therefore, terminal plate 160 can be used as an external positive electrode connected to an internal positive electrode. Figure 2 and Figure 3 As shown, the terminal plate 160 may include a flange portion at the lower side and a protrusion at the upper side. The flange portion can be electrically connected to the first substrate contact 210. Therefore, the secondary battery with this structure can improve its internal pressure resistance, thereby ensuring the operational stability of the secondary battery. However, the structure of the terminal plate 160 is not limited to this arrangement, and the terminal plate 160 may have a flange portion at the upper side and a protrusion at the lower side. In this case, the first substrate contact 210 can be electrically connected to the protrusion at the lower side.

[0090] According to some embodiments of this disclosure, a base plate 180 closes a second opening formed on the other side of a sidewall portion 122 of the housing 120 and is electrically connected to a second electrode 240, thereby serving as an external negative electrode connected to an internal negative electrode, similar to how the terminal plate 160 functions. The base plate 180 may also be electrically connected to the sidewall portion 122 of the housing 120. For example, the base plate 180 may be electrically connected to the housing 120 by welding, but is not limited thereto. They may also be electrically connected by physically inserting components such as rivets. Figure 14 The image shows an example of electrically connecting the base plate to the housing by welding.

[0091] According to some embodiments of the present disclosure, the secondary battery 10 may additionally include an insulator 140 located between the cover portion 121 and the terminal plate 160 to insulate the cover portion 121 from the terminal plate 160. Figures 1 to 3 An example is shown where the terminal plate 160 is housed within the secondary battery 10. The insulator 140 may comprise a material such as polypropylene, nylon, or silicone (Si), for example, to provide electrical insulation between the housing 120, which serves as a different external electrode, and the terminal plate 160. However, it is not limited to such materials, and any insulating material having electrical insulating properties and chemical stability may be used. Therefore, the insulator 140 can prevent or reduce electrical short circuits between the housing 120 and the terminal plate 160, ensuring the safety of the secondary battery 10. According to some embodiments, the insulator 140 may be clamped between the cover portion 121 and the terminal plate 160 under pressure. However, the method of forming the insulator 140 is not limited to this; for example, an insulating coating formed by a coating method may be used instead of a physically formed or arranged insulator.

[0092] According to some embodiments of this disclosure, housing 120 and base plate 180 may comprise stainless steel (SUS). However, they are not limited thereto and may comprise any conductive material that does not cause side reactions with the electrolyte, such as aluminum, aluminum alloys, or nickel-plated steel. According to some embodiments, terminal plate 160 may comprise aluminum (Al). However, like housing 120 and base plate 180, terminal plate 160 may be made of copper (Cu), nickel foil, or another metal commonly used in the art.

[0093] Figure 4 According to some embodiments of this disclosure Figure 3 A magnified view of part R.

[0094] refer to Figure 4This diagram illustrates a portion of the electrode assembly 200, as well as the structure of the housing 120, base plate 180, and terminal plate 160, and their interconnections. Furthermore, it shows the sequential winding structure of the first electrode 230, diaphragm 250, and second electrode 240 included in the electrode assembly 200, and the stacked structure of the housing 120, insulator 140, and terminal plate 160. Specifically, the following... Figure 4 The description focuses on the relationship between the first substrate terminal block 210 and the second substrate terminal block 220, which are electrically connected to the terminal block 160 and the base plate 180, respectively.

[0095] According to some embodiments of this disclosure, the first substrate tab 210 can extend vertically from the first substrate of the first electrode 230 and is electrically connected to the terminal block 160 (e.g., by soldering or another method). Figure 4 As shown, the first substrate terminal piece 210 can be bent toward the center of the secondary battery to reduce the space it occupies in the vertical direction inside the secondary battery and maximize or relatively increase the utilization of internal space. However, the first substrate terminal piece 210 does not need to be bent and can extend straight from the first substrate in the vertical direction to be electrically connected to the terminal plate 160.

[0096] According to some embodiments, the first substrate tab 210 may include a first vertical portion 211 extending vertically from the first coated portion and a first contact portion 212 that bends from the first vertical portion 211 and extends toward the center of the secondary battery. For example, after forming the first vertical portion 211, a press may mechanically bend the first vertical portion 211 to form the first contact portion 212. However, it is not limited thereto, and in various embodiments of this disclosure, the first vertical portion 211 may be directly electrically connected to the terminal block 160 without the first contact portion 212.

[0097] According to some embodiments of this disclosure, the second substrate terminal block 220 can extend vertically from the second substrate of the second electrode 240 and is electrically connected to the substrate 180, for example, by soldering or other methods. The second substrate terminal block 220 can extend in the opposite direction to the first substrate terminal block 210. Furthermore, as... Figure 4 As shown, the second substrate terminal 220 can be configured to be bent toward the center of the secondary battery 10. Similar to the first substrate terminal 210, this configuration reduces the length occupied by the second substrate terminal 220 in the vertical direction inside the secondary battery and maximizes or relatively improves internal space efficiency. However, it is not limited to this; the second substrate terminal 220 does not need to be bent and can be electrically connected to the base plate 180 inside the secondary battery in a state of extending straight from the second substrate in the vertical direction.

[0098] According to some embodiments, the second substrate tab 220 may include a second vertical portion 221 extending vertically from the second coated portion and a second contact portion 222 bending from the second vertical portion 221 toward the center of the secondary battery. For example, after forming the second vertical portion 221, a pressing machine may bend the second vertical portion 221 to form the second contact portion 222. However, according to various embodiments of the present disclosure, if the second vertical portion 221 is directly electrically connected to the substrate 180, the second contact portion 222 is not required.

[0099] According to some embodiments of this disclosure, the first substrate terminal block 210 and the second substrate terminal block 220 can replace conventional electrode terminal blocks. Therefore, the space occupied by the electrode terminal blocks and cover strips in the secondary battery can be eliminated, and the electrode assembly 200 can have a near-circular shape when viewed vertically. This can maximize or relatively improve the space efficiency of the internal structure of the secondary battery.

[0100] Figure 5 An example of a terminal board 500 according to some embodiments of the present disclosure is shown. Figure 5 The terminal block 500 shown can be used with Figures 1 to 3 The terminal block 160 is basically the same.

[0101] refer to Figure 5 The terminal plate 500 may include a protrusion 540 inserted into a first opening formed at the center of the housing and a flange portion 520 located below the protrusion 540. The flange portion 520 may be located between the electrode assembly and the cover portion. This differs from conventional stainless steel secondary battery terminal plates in that it has a different shape for electrically connecting a first substrate tab used as a positive electrode. With this structure, the flange portion 520 can be electrically connected to the first substrate tab (e.g., by welding), enabling the terminal plate 500 to function as an external positive electrode. Furthermore, the flange portion 520 at the lower side can increase the secondary battery's resistance to internal pressure and ensure operational stability. Therefore, because the secondary battery can have a tabless structure without electrode tabs and a cover strip, the energy density of the secondary battery can be increased. In addition, because the coated area of ​​the electrode plate is increased, the capacity of the secondary battery can be maximized or relatively increased.

[0102] However, as mentioned above, the internal structure of the terminal board 500 is not limited to... Figure 5 The structure is shown. For example, as long as the terminal plate 500 can be electrically connected to the first electrode, the flange portion 520 can be positioned above the protrusion 540 in the same manner as in conventional designs. As another example, a terminal plate having a cylindrical structure in which the protrusion 540 and the flange portion 520 are not separated can be inserted into the first opening.

[0103] Figure 6 An example of a first electrode 600 prior to the formation of a first substrate tab is shown according to some embodiments of the present disclosure. Figure 7 An example of a first electrode 700 after the formation of a first substrate tab 720 is shown according to some embodiments of the present disclosure. Figure 8 An example of a second electrode 800 prior to the formation of a second substrate tab is shown according to some embodiments of the present disclosure. Figure 9 An example of a second electrode 900 after the formation of a second substrate tab 920 is shown according to some embodiments of the present disclosure.

[0104] refer to Figure 6 and Figure 7 The diagram shows a first electrode 600, 700 that can be used as a positive electrode, a first coated portion 640, 740 where a first active material layer is placed, a first uncoated portion 660, 760 where the first active material layer is not present, a region 620 of a first substrate extending vertically from the first coated portions 640, 740, and a first substrate tab 720. However, Figure 6 and Figure 7 The length and structure of the first electrodes 600, 700 and their sub-components shown are not limited to those shown. For example, the first coated portions 640, 740 may extend further downward.

[0105] According to some embodiments, the first coated portions 640, 740 are located on the first substrate of the first electrodes 600, 700, and may include a first active material layer. The first coated portions 640, 740 can be formed by coating a positive electrode active material, such as a transition metal oxide, onto the first substrate during the manufacture of the first electrodes 600, 700. For example, the first active material layer can be placed on the first substrate by a coating method. According to some embodiments, first uncoated portions 660, 760, where the first active material layer is absent, can be formed at both ends of the first coated portions 640, 740.

[0106] refer to Figure 7 According to some embodiments of the present disclosure, the first electrode 700 may include at least one first substrate tab 720. Figure 7 Show Figure 6In the first electrode 600, a region 620 of the first substrate, extending vertically, is slotted to form a first substrate tab 720. According to some embodiments, a first portion 722 of the first electrode 600 where the first active material layer is absent can be removed, leaving a second portion. The second portion can be cut at intervals (e.g., set or predetermined intervals) to form at least one first substrate tab 720. To ensure process efficiency and / or process consistency, the first portion 722 having lengths (e.g., set or predetermined lengths) l1, l2 can be removed, and one or more first substrate tabs 720 can then be formed. However, because the length cut for forming the first substrate tab is set or predetermined for process standardization, the cutting length does not need to be predetermined if the first electrode is formed in another manner.

[0107] refer to Figure 8 and Figure 9 The diagram shows second electrodes 800 and 900 that can be used as negative electrodes, second coated portions 840 and 940 where a second active material layer is placed, second uncoated portions 860 and 960 where no second active material layer is present, a region 820 of a second substrate extending vertically from the second coated portions 840 and 940, and a second substrate tab 920. However, Figure 8 and Figure 9 The length and structure of the second electrodes 800, 900 and their sub-components shown are not limited thereto. For example, the second coating portions 840, 940 may extend further upward.

[0108] According to some embodiments, the second coated portions 840, 940 are located on the second substrate of the second electrodes 800, 900, and may include a second active material layer. The second coated portions 840, 940 can be formed by coating a negative electrode active material, such as graphite, onto the second substrate during the manufacture of the second electrodes. For example, the second active material layer can be placed on the second substrate by a coating method. According to some embodiments, second uncoated portions 860, 960, where the second active material layer is absent, can be formed at both ends of the second coated portions 840, 940.

[0109] refer to Figure 9 According to some embodiments of the present disclosure, the second electrode 900 may include at least one second substrate terminal block 920. Figure 9 Show Figure 8In the second electrode 800, a region 820 of the second substrate, extending vertically, is slotted to form a second substrate tab 920. According to some embodiments, a first portion 922 of the region of the second electrode 900 where the second active material layer is absent can be removed, leaving a second portion. The second portion can be cut at intervals (e.g., set or predetermined intervals) to form at least one second substrate tab 920. For process efficiency, the first portion 922 having lengths (e.g., set or predetermined lengths) l3, l4 can be removed, thereby forming one or more second substrate tabs 920. Similarly, because the length cut for forming the second substrate tab is set or predetermined for process standardization, the cutting length does not need to be predetermined if the second electrode is formed in another manner.

[0110] According to some embodiments, the lengths (e.g., a set or predetermined length) l3, l4 used for cutting and forming the second substrate terminal piece can be shorter than the lengths (e.g., a set or predetermined length) l1, l2 used for cutting and forming the first substrate terminal piece. As a result, after winding the electrode assembly, the length of the first substrate terminal piece 720 in the winding direction of the electrode assembly can be shorter than the length of the second substrate terminal piece 920 in the winding direction. (Refer to the above...) Figures 1 to 4 This allows for the formation of a terminal board extending into the secondary battery without causing a short circuit with the secondary battery housing, thereby allowing the terminal board to be electrically connected to the first substrate terminal block 720.

[0111] According to some embodiments, after the electrode assembly is wound, the length of the first substrate tab 720 in the winding direction of the electrode assembly may be shorter than the length of the first coating portions 640 and 740 in the winding direction. Furthermore, the length of the second substrate tab 920 in the winding direction of the electrode assembly may be shorter than the length of the second coating portions 840 and 940 in the winding direction.

[0112] According to some embodiments, because the first substrate tab 720 and the second substrate tab 920 can be formed without requiring any separate electrode tabs or cover strips in the first and second uncoated portions, the lengths of the first and second uncoated portions can be significantly reduced, or may not exist at all, compared to conventional lengths. Therefore, by ensuring a larger coated area, the capacity of the secondary battery can be increased.

[0113] like Figures 6 to 9 The shapes of the first substrate terminal block 720 and the second substrate terminal block 920 are not limited thereto, as shown and described in detail. The number and shape of the substrate terminal blocks can vary as long as they can be electrically connected to the base plate and terminal plate used as external electrodes. For example, with... Figure 9As shown, the second substrate terminal block can be formed in a diamond shape, with its width at the bottom being narrower than that at the top. As another example, multiple first substrate terminal blocks can be formed at intervals, separated from each other.

[0114] Figure 10 Examples of secondary batteries before and after bending the first substrate tab are shown according to some embodiments of the present disclosure. Figure 11 An example is shown in which a first substrate tab is electrically connected to a terminal block along the winding direction of an electrode assembly, according to some embodiments of the present disclosure.

[0115] refer to Figure 10 This illustrates the transition from the unbent first substrate tab 210-1 to the bent first substrate tab 210-2 before the electrode assembly 200 is electrically connected to the terminal block. Figure 10 The lower structure of the electrode assembly 200 is also depicted, which includes a second substrate terminal block 220, a first electrode 230, a second electrode 240, and a diaphragm 250. Figure 10 and Figure 11 The focus is on the bending process of the first substrate terminal piece 210 and the method of electrically connecting the first electrode 230 to the terminal block 160.

[0116] refer to Figure 10 In (a), before bending, the first substrate tab 210-1 can extend vertically from the first electrode 230. (See reference...) Figure 10 In (b), after bending, the first substrate terminal piece 210-1 is formed by mechanically bending (e.g., using a press or bending machine) the portion of the first substrate terminal piece 210-1 extending vertically from the first substrate so that it faces the center of the secondary battery, thus forming a bent first substrate terminal piece 210-2. For example, a press or bending machine can apply physical force to a specific portion of the vertically extending portion, bending it towards the center to form the first substrate terminal piece 210-2. In this way, the first substrate terminal piece 210 is electrically connected to the terminal plate 160, allowing the terminal plate 160 to be used as an external electrode. Furthermore, the vertical space occupied by the first substrate terminal piece 210 is reduced, thereby preserving the internal capacity in the secondary battery. However, as mentioned above, the first substrate terminal piece 210 does not need to be bent towards the center of the secondary battery and can be directly electrically connected to the terminal plate 160; in this case, it can be omitted. Figure 10 The bending process is shown in the figure.

[0117] like Figure 11As shown in (a), the first substrate tab 210 is electrically connected to the terminal block 160. According to some embodiments, the electrical connection can be achieved by soldering using soldering equipment W1. However, the connection method is not limited to soldering. It can include any method capable of achieving an electrical connection without damaging the metal surface or the first substrate tab 210, such as ultrasonic bonding, where ultrasonic energy is used to locally heat and press the metal surface and the first substrate tab 210 together to join them.

[0118] refer to Figure 11 In (b), the welding equipment W1 can electrically connect the first substrate tab 210 and the terminal plate 160 along the winding direction of the electrode assembly. Therefore, each first substrate tab 210 formed on the first electrode wound along the winding direction of the electrode assembly can be electrically connected to the terminal plate 160. Although Figure 11 (b) in the diagram appears to show a fixed welding direction and number of welds, but is not limited to such an arrangement. For example, the welding direction may be set along a line that overlaps with the terminal block 160 in a direction parallel to the vertical direction along the first substrate tab 210.

[0119] Figure 12 Examples of secondary batteries before and after bending the second substrate tab are shown according to some embodiments of the present disclosure. Figure 13 An example is shown in which a second substrate terminal block is electrically connected to the base plate along the winding direction of the electrode assembly, according to some embodiments of the present disclosure. Figure 14 Examples are shown where, according to some embodiments of the present disclosure, the base plate and the sidewall portions of the housing are electrically connected by welding. Specifically, Figures 12 to 14 The insulator 140 and housing 120 can be depicted and additionally connected to the reference. Figure 10 and Figure 11 The description covers the electrode assembly and terminal block. In other words, Figures 12 to 14 The electrode assembly 200 and terminal plate 160 in the reference can be used with Figure 10 and Figure 11 The electrode assembly 200 and terminal board 160 described are essentially the same. See below for reference. Figure 16 A detailed description is provided of how the insulator 140 and the housing 120 are connected during the manufacture of a secondary battery.

[0120] refer to Figure 12 This illustrates the transition from the unbent second substrate tab 220-1 to the bent second substrate tab 220-2 before the electrode assembly 200 is electrically connected to the terminal block 160. Figure 12 The upper structure of the electrode assembly 200 is also shown, which includes a first substrate terminal block 210, a first electrode 230, a second electrode 240 and a diaphragm 250. Figures 12 to 14The process focuses on the bending process of the second substrate terminal 220, the method of electrically connecting the second electrode 240 to the base plate 180, and the method of connecting the base plate 180 to the side wall portion 122 of the housing 120.

[0121] refer to Figures 12 to 14 The diagram illustrates the process of electrically connecting the second electrode 240 to the base plate 180 at the lower end of the housing 120, and the process of connecting the base plate 180 to the side wall portion 122 of the housing. However, this illustration is provided merely for ease of explanation, and during the actual connection process, the secondary battery can be inverted in the vertical direction to facilitate connection. For example, the secondary battery can be flipped so that the base plate 180 faces upwards, and then the connection process can be performed.

[0122] refer to Figure 12 In (a), the second substrate tab 220-1, before bending, can extend vertically from the second electrode 240. (See reference...) Figure 12 In (b), after bending, the second substrate terminal piece 220-2 can be bent such that the portion previously extending vertically from the second substrate can be directed toward the center of the secondary battery by mechanical methods such as pressing or bending. For example, a pressing machine or bending machine can apply physical force toward the center of the secondary battery on the vertically extending portion of the second substrate, thereby mechanically bending the second substrate terminal piece 220-1. As a result, the second substrate terminal piece 220 is electrically connected to the base plate 180, allowing the base plate 180 to be used as an external electrode. In addition, the portion of the second substrate terminal piece 220 occupying in the vertical direction within the secondary battery is reduced, thereby ensuring internal capacity. However, as mentioned above, the second substrate terminal piece 220 does not necessarily need to be bent toward the center of the secondary battery, but can instead be directly connected to the base plate 180 in a conductive manner. In this case, it can be omitted. Figure 12 The bending process of the second substrate terminal piece 220 described in the document.

[0123] Figure 13 The process of electrically connecting the second substrate terminal block 220 to the substrate 180 is shown. According to some embodiments, see reference... Figure 13 In (a), the electrical connection can be achieved by welding using welding equipment W2. However, the connection method is not limited to welding and can include any method that can form an electrical connection without damaging the metal surface or the second substrate tab 220, such as cold welding, which uses high pressure without heating to form atomic bonds.

[0124] refer to Figure 13 In (b), the welding equipment W2 can electrically connect the second substrate tab 220 and the base plate 180 along the winding direction of the electrode assembly. Therefore, each second substrate tab 220 formed on the second electrode wound along the winding direction of the electrode assembly can be electrically connected to the base plate 180. Although Figure 13 (b) in the diagram appears to show a fixed welding direction and number of welds, but is not limited thereto. For example, the welding direction may be set along a line that overlaps with the base plate 180 in a direction parallel to the vertical direction along the second substrate tab 220.

[0125] Figure 14 The process of electrically connecting the base plate 180 and the side wall portion 122 of the housing 120 is shown. This can be performed by welding using welding equipment W3, but is not limited to this. For example, they can be physically connected by rivets. In this way, the housing 120 and the base plate 180 are electrically connected such that the base plate 180 and the housing 120, which are electrically connected to the second substrate terminal piece 220, can simultaneously serve as external electrodes. Furthermore, when the base plate 180 is attached to the housing 120, the second opening formed on the other side of the side wall portion 122 can be closed. Therefore, the coin-type battery can have an external structure that seals the secondary battery and houses the electrode assembly.

[0126] Figure 15 This is a diagram showing the state of the electrode assembly 1520 housed in the housing 1510 from a vertical perspective.

[0127] refer to Figure 15 The diagram shows an arrangement in which the electrode assembly 1520 is positioned in close contact with a portion of the sidewall of the housing 1510 (e.g., contacting a portion of the sidewall of the housing 1510), and a partially enlarged view shows the portion of the electrode assembly 1520 in close contact. Furthermore, Figure 15 The radius Jr of the electrode assembly 1520, measured from the center of the secondary battery, and the radius CR of the inner sidewall portion of the housing 1510 are shown.

[0128] According to some embodiments, the electrode assembly 1520 is positioned in close contact with a sidewall portion of the housing 1510 (e.g., contacting a sidewall portion of the housing 1510), thereby allowing it to have a near-circular shape when viewed from the vertical direction. Therefore, the amount of electrolyte that can be charged into the secondary battery can be increased, thereby increasing the single-cell capacity of the secondary battery. The space utilization of this secondary battery can be evaluated by a "circularity ratio," which is the ratio of the radius Jr of the electrode assembly to the radius CR of the inner sidewall portion of the housing 1510, according to the following equation (1):

[0129] Equation (1)

[0130] Circularity = (Radius of smallest circumcircle - Radius of smallest incircle) / (Radius of smallest circumcircle)

[0131] Here, the closer the roundness is to 0, the higher the efficiency of inserting the electrode assembly 1520 into the housing 1510. In equation (1) above, the radius of the smallest inscribed circle can be the radius JR of the electrode assembly 1520, and the radius of the largest inscribed circle can be the radius CR of the inner sidewall portion of the housing 1510. According to some embodiments of this disclosure, instead of the electrode tabs and cover strips present on the outer portion of the electrode assembly, the first substrate tab and the second substrate tab replace the function of the electrode tabs. That is, no other components can be located on the outer portion of the electrode assembly. Therefore, the roundness of the electrode assembly according to equation (1) can be 0 or can be approximately 0.

[0132] However, equation (1) is merely one formula for evaluating the space utilization efficiency of an electrode assembly. If the electrode assembly has a shape other than a cylinder, space utilization efficiency can be evaluated in another way. For example, the ratio of the internal area of ​​the electrode assembly to the internal area within the sidewall portion of the housing can be used to evaluate space utilization efficiency.

[0133] Figure 16 This is a flowchart 1600 illustrating an example of a method for manufacturing a secondary battery according to some embodiments of the present disclosure. The method can be performed by a secondary battery manufacturing apparatus.

[0134] refer to Figure 16 According to some embodiments, the method can begin by forming an electrode assembly including a first electrode, a diaphragm, and a second electrode (S1610). Here, the first electrode can be used as a positive electrode, and the second electrode can be used as a negative electrode.

[0135] Next, the method may include electrically connecting a first electrode of the electrode assembly to a terminal board (S1620). Here, the first electrode to be electrically connected to the terminal board may include at least one first substrate tab.

[0136] Next, the method may include inserting an electrode assembly and a terminal block into a housing, the housing including a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly (S1630).

[0137] Alternatively, the method may include connecting a base plate to an opening formed on the other side of the sidewall portion and electrically connecting a second electrode to the base plate (S1640). Here, the second electrode electrically connected to the base plate may include at least one second substrate terminal block.

[0138] According to some embodiments, forming an electrode assembly may include forming a first substrate tab. Forming the first substrate tab may include removing a first portion from a region of the first substrate of the first electrode where a first active material layer is absent, leaving a second portion, and cutting the second portion at regular intervals to form at least one first substrate tab. (See above references.) Figure 6 and Figure 7 A detailed description of this step is provided.

[0139] According to some embodiments, forming an electrode assembly may include forming a second substrate tab. Forming the second substrate tab may include removing a first portion from a region of the second substrate of the second electrode where a second active material layer does not exist, leaving a second portion, and cutting the second portion at regular intervals to form at least one second substrate tab. (See above for reference.) Figure 8 and Figure 9 A detailed description of this step is provided.

[0140] According to some embodiments, electrically connecting the first electrode to the terminal block may include bending the first substrate tab and soldering the bent first substrate tab to the terminal block. Similarly, the above references... Figure 10 and Figure 11 A detailed description of this step is provided.

[0141] According to some embodiments, electrically connecting the second electrode to the base plate may include bending a second substrate connector, welding the bent second substrate connector to the base plate, and welding the base plate to a sidewall portion. (See above for reference.) Figures 12 to 14 A detailed description of this step is provided.

[0142] According to some embodiments, the insertion step may include placing the electrode assembly such that its outer portion is in close contact with a sidewall portion of the housing. Figure 15 The electrode assembly and housing are shown as viewed vertically after this insertion. With the electrode assembly in such close contact, the internal space of the secondary battery can be used more efficiently. Therefore, the amount of electrolyte that can be charged into the secondary battery can be increased, and the battery capacity can be increased.

[0143] According to some embodiments, the insertion step may include placing an insulator between the cover portion and the terminal plate, and applying heat to the cover portion and the terminal plate to close a first opening formed at the center of the cover portion. In doing so, it may become possible to prevent or reduce leakage of electrolyte or other internal components of the secondary battery, and relatively increase the yield of the fully sealed secondary battery containing the electrode assembly.

[0144] Figure 16The flowchart and the above description are merely examples of this disclosure, and the scope of this disclosure is not limited thereto. For example, one or more steps in the flowchart and the above description may be added, changed, or omitted; the order of one or more steps may be changed; or one or more steps may be performed simultaneously.

[0145] Although this disclosure has been described above with reference to embodiments and the accompanying drawings illustrating aspects thereof, this disclosure is not limited thereto. Various modifications and variations can be made by those skilled in the art within the spirit of this disclosure and within the scope of the following claims and their equivalents.

Claims

1. A secondary battery, comprising: An electrode assembly includes a first electrode, a second electrode, and a diaphragm between the first electrode and the second electrode; The housing includes a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly; A terminal plate that closes the first opening formed at the center of the cover portion and is electrically connected to the first electrode; as well as The base plate closes the second opening formed on the other side of the sidewall portion and is electrically connected to the second electrode. The first electrode includes at least one first substrate terminal block electrically connected to the terminal board, and The second electrode includes at least one second substrate terminal block electrically connected to the base plate.

2. The secondary battery according to claim 1, in, The first electrode further includes a first coated portion and first uncoated portions provided at both ends of the first coated portion. In the first coated portion, a first active material layer is on a first substrate of the first electrode, and in the first uncoated portions, the first active material layer is absent. The second electrode further includes a second coated portion and second uncoated portions provided at both ends of the second coated portion. In the second coated portion, a second active material layer is formed on a second substrate of the second electrode, and in the second uncoated portions, the second active material layer is absent. Wherein, at least one first substrate terminal protrudes from the first substrate of the first electrode toward the terminal plate, and In this embodiment, at least one second substrate terminal protrudes from the second substrate of the second electrode toward the base plate.

3. The secondary battery according to claim 2, in, The at least one first substrate terminal includes a first vertical portion extending vertically from the first coated portion and a first contact portion that bends from the first vertical portion and extends toward the center of the secondary battery. The at least one second substrate terminal includes a second vertical portion extending from the second coated portion in the vertical direction and a second contact portion extending from the second vertical portion toward the center of the secondary battery.

4. The secondary battery according to claim 2, in, The length of at least one first substrate terminal piece in the winding direction of the electrode assembly is shorter than the length of the first coated portion in the winding direction. Wherein, the length of the at least one second substrate terminal piece in the winding direction is shorter than the length of the second coated portion in the winding direction.

5. The secondary battery according to claim 4, in, The length of the at least one first substrate terminal block in the winding direction is shorter than the length of the at least one second substrate terminal block in the winding direction.

6. The secondary battery according to claim 1, in, The terminal block overlaps with the at least one first substrate terminal piece in the vertical direction, and Wherein, the at least one first substrate terminal piece is located inside the terminal plate in the horizontal direction.

7. The secondary battery according to claim 1, in, The at least one first substrate terminal piece extends closer to the terminal plate in the vertical direction than it would be near the diaphragm, and Wherein, the at least one second substrate terminal extends closer to the base plate in the vertical direction than to the diaphragm.

8. The secondary battery according to claim 1, It further includes an insulator between the cover portion and the terminal plate, which insulates the cover portion from the terminal plate.

9. The secondary battery according to claim 1, in, The terminal plate includes a protrusion inserted into the first opening and a flange portion below the protrusion, and The flange portion is located between the electrode assembly and the cover portion.

10. The secondary battery according to claim 1, in, The at least one first substrate terminal piece is soldered to the terminal board, and The at least one second substrate terminal block is connected to the base plate by welding.

11. The secondary battery according to claim 1, in, The base plate and the housing are made of stainless steel, and The terminal block comprises aluminum.

12. The secondary battery according to claim 1, in, The outer portion of the electrode assembly contacts the sidewall portion.

13. The secondary battery according to claim 1, in, The sidewall portion and the cover portion are integrally formed.

14. A method for manufacturing a secondary battery, the method comprising: An electrode assembly comprising a first electrode, a diaphragm, and a second electrode is formed; The first electrode of the electrode assembly is electrically connected to the terminal board; The electrode assembly and the terminal plate are inserted into a housing, the housing including a sidewall portion surrounding a side surface of the electrode assembly and a cover portion extending horizontally from one side of the sidewall portion and located on the electrode assembly; as well as The base plate is connected to an opening formed on the other side of the sidewall portion, and the second electrode is electrically connected to the base plate. The first electrode includes at least one first substrate terminal block electrically connected to the terminal board, and The second electrode includes at least one second substrate terminal block electrically connected to the base plate.

15. The method according to claim 14, in, The formation of the electrode assembly includes forming at least one first substrate terminal block, and Wherein, forming the at least one first substrate terminal block includes: Remove the first portion from the region of the first substrate of the first electrode where the first active material layer does not exist, leaving the second portion; and The second portion is cut at regular intervals to form at least one first substrate terminal block.

16. The method according to claim 14, in, The formation of the electrode assembly includes forming at least one second substrate terminal block, and Wherein, forming the at least one second substrate terminal block includes: Remove the first portion from the region of the second substrate of the second electrode where the second active material layer does not exist, leaving the second portion; and The second portion is cut at regular intervals to form the at least one second substrate terminal block.

17. The method according to claim 14, in, The step of electrically connecting the first electrode to the terminal board includes: Bending at least one first substrate terminal piece; and The bent at least one first substrate terminal piece is soldered to the terminal block.

18. The method according to claim 14, in, The step of electrically connecting the second electrode to the base plate includes: Bending at least one of the second substrate terminals; The bent at least one second substrate terminal piece is welded to the base plate; and The base plate is welded to the side wall portion.

19. The method according to claim 14, in, Inserting the electrode assembly and the terminal plate into the housing includes arranging the electrode assembly such that the outer portion of the electrode assembly contacts the sidewall portion.

20. The method according to claim 14, in, The step of inserting the electrode assembly and the terminal plate into the housing includes: An insulator is arranged between the cover portion and the terminal plate; and Heat is applied to the cover portion and the terminal plate to seal the opening formed at the center of the cover portion.

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