Method for manufacturing secondary battery and secondary battery manufactured using the same

Abstract

Disclosed are a method for manufacturing a secondary battery and a secondary battery manufactured using the same, the method comprising: electrically connecting a first current collector plate to a first electrode plate of an electrode assembly, the electrode assembly comprising the first electrode plate, a second electrode plate, and a separator between the first electrode plate and the second electrode plate; pressing the first current collector plate by a set pressing amount in a direction of the electrode assembly to press at least a portion of the separator protruding outward from the electrode assembly with respect to the first electrode plate; and performing an internal insulation process in which a set pressing amount may be set based on a length of an initial gap between the first current collector plate and the separator and a length of an initial separator pressing allowance space between the separator and the first electrode plate.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0036414 filed on March 15, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] Aspects of some embodiments of the present disclosure relate to a method for manufacturing a secondary battery and a secondary battery manufactured using the method. Background Art

[0003] Unlike primary batteries, which are not designed to be (re)charged, secondary (or rechargeable) batteries are designed to be discharged and charged. Low-capacity secondary batteries are used in small portable electronic devices such as smartphones, feature phones, notebook computers, digital cameras, and camcorders, while large-capacity secondary batteries are widely used as power sources for driving motors in hybrid and electric vehicles and for storing electricity (e.g., home and / or utility-scale electricity storage). Secondary batteries typically include an electrode assembly consisting of a positive electrode and a negative electrode, a casing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0004] Meanwhile, in recent years, interest in electric vehicles has increased in order to prevent or reduce environmental pollution, and therefore, high-capacity secondary batteries are being adopted for electric vehicles. These secondary batteries can desirably have characteristics such as high density, high output, and stability.

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

[0006] Aspects of some embodiments of the present disclosure include a method for manufacturing a secondary battery, in which capacity is increased by securing an inner space of a case and flow of an electrode assembly inside the case can be suppressed, and a secondary battery manufactured using the method.

[0007] 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.

[0008] According to some embodiments of the present disclosure, in a method for manufacturing a secondary battery, the method includes: electrically connecting a first current collector plate to a first electrode plate of an electrode assembly, the electrode assembly including a first electrode plate, a second electrode plate, and a diaphragm, the diaphragm being between the first electrode plate and the second electrode plate and including a diaphragm extrusion margin space and a portion that is not squeezed even when squeezed; squeezing the first current collector plate with a set extrusion amount in the direction of the electrode assembly to squeeze at least a portion of the diaphragm extrusion margin space of the diaphragm that protrudes outward from the electrode assembly relative to the first electrode plate; and performing internal insulation treatment, wherein the set extrusion amount can be set based on the length of an initial gap between the first current collector plate and the diaphragm and the length of an initial diaphragm extrusion margin space between the diaphragm and the first electrode plate.

[0009] According to some embodiments, the step of pressing the first current collector plate may include bringing the separator and the first current collector plate into close contact with each other such that there is no gap therebetween.

[0010] According to some embodiments, the initial diaphragm extrusion margin space can be set to a length obtained by subtracting the length between the end of the portion of the diaphragm that is not squeezed even when squeezed and the protruding position of the first electrode plate and the length between the protruding position of the first electrode plate and the alignment position of the first electrode plate from the length between the end of the diaphragm extrusion margin space of the diaphragm and the alignment position of the first electrode plate.

[0011] According to some embodiments, a region corresponding to a length between a protruding position of the first electrode plate and an aligned position of the first electrode plate may be a reversal prevention region of the positive electrode position and the negative electrode position.

[0012] According to some embodiments, a region corresponding to a length between an end portion of the separator and a protruding position of the first electrode plate may be a positive-negative electrode short circuit preventing region.

[0013] According to some embodiments, after the first current collector plate is compressed, the length of the initial separator compression allowance space may be reduced.

[0014] According to some embodiments, after the first current collector plate is pressed, the length of the initial design width of the separator may be reduced.

[0015] According to some embodiments, after electrically connecting the first current collector plate to the first electrode plate, further comprising coupling a first insulating plate to one side of the first current collector plate.

[0016] According to some embodiments, performing the internal insulation process may include attaching an insulation member to at least one side of the electrode assembly and the first insulation plate.

[0017] According to some embodiments, the step of pressing the first current collector plate may include pressing a side surface of the separator plate based on a length direction of the electrode assembly.

[0018] According to some embodiments, the set pressing amount may be set to 0.7% to 1.2% of the length between the outer surface of the first collector plate before pressing the first collector plate and the outer surface of the second collector plate coupled to the other side of the electrode assembly.

[0019] According to some embodiments, the length of the initial diaphragm squeeze margin space may be set to 0.84% ​​to 0.86% of the initial design width of the diaphragm.

[0020] According to some embodiments, the length of the changed separator crushing allowance space after the first current collector plate is crushed may be 38% to 42% of the length of the initial separator crushing allowance space.

[0021] According to some embodiments of the present disclosure, a secondary battery may be manufactured by a secondary battery manufacturing method.

[0022] According to some embodiments, the end portion of the separator and the first current collector plate may be in close contact with each other without a gap.

[0023] According to some embodiments, at least a portion of the first current collector plate may be coupled to the separator crush allowance space of the separator.

[0024] According to some embodiments, the present invention may include: a case accommodating the electrode assembly and the first current collector plate and being open at both sides; a first cover plate sealing the one-side opening of the case; and a first terminal electrically connected to the first current collector plate and exposed outside the first cover plate.

[0025] According to some embodiments, a first protruding current collector plate connected to an outer surface of the first current collector plate and contacting and coupled to an inner surface of the first terminal may be further included. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 is a perspective view of a secondary battery according to some embodiments of the present disclosure.

[0028] Figure 2 It is along Figure 1 A cross-sectional view of a secondary battery taken along line 2-2'.

[0029] Figures 3A to 3Cis a diagram for explaining a pressing operation of a method for manufacturing a secondary battery according to some embodiments of the present disclosure.

[0030] Figure 4 is a diagram illustrating a state of a separator according to some embodiments of the present disclosure before being bonded to a current collector.

[0031] Figure 5 is a diagram illustrating a state of a separator after being bonded to a current collector according to some embodiments of the present disclosure.

[0032] Figure 6 is a diagram illustrating a state after the first current collector plate is pressed according to some embodiments of the present disclosure.

[0033] Figure 7 is a perspective view of an example of a battery module.

[0034] Figure 8A and Figure 8B A perspective view illustrating an example of a battery pack is shown.

[0035] Figure 9A and Figure 9B Perspective and side views of examples of vehicle bodies and vehicle components are shown. DETAILED DESCRIPTION

[0036] Hereinafter, 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 interpreted as limited to the ordinary meaning or dictionary meaning, but 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 so as to best explain his / her invention.

[0037] The embodiments described in this specification and the configurations shown in the accompanying drawings are only some of the embodiments of the present disclosure and do not represent all 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.

[0038] 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” or “connected to” a second element, the first element can be directly coupled to or directly connected 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.

[0039] In the figures, the dimensions of various elements, layers, etc. may be exaggerated for clarity. Identical reference numerals represent 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." When expressions such as "at least one of..." and "any of..." follow a list of elements, they modify the entire list of elements, not the individual elements in that 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 refer to 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, 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 (essentially or approximately)", "approximately" and similar terms are used as terms of approximation, not as terms of degree, and are intended to account for the inherent variations in measured or calculated values ​​that one of ordinary skill in the art would recognize.

[0040] It will be understood that, although the terms first, second, third, etc. can 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 can be referred to as the second element, second component, second region, second layer or second part.

[0041] For ease of description, spatially relative terms such as “under,” “beneath,” “below,” “above,” and “on” 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.

[0042] 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, steps, operations, elements, and / or components is indicated, but the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof is not excluded.

[0043] 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 (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 expressly describe any subranges contained within the ranges expressly described herein. All such ranges are intended to be inherently described in this specification so that modifications to expressly describe any such subranges will meet the requirements.

[0044] 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 variations that are considered low in the art (e.g., 5% or less). Furthermore, when a parameter is referred to as uniform in a given area, this may mean that it is uniform with respect to the average value.

[0045] Throughout the specification, unless stated otherwise, each element may be in the singular or in the plural.

[0046] When any element is referred to as being disposed (or positioned or located) “on (or below)” or “on (or below)” a component, this may mean that the arbitrary element is placed in contact with the upper (or lower) surface of the component, and may also mean that another component may be interposed between the component and the arbitrary element disposed (or positioned or located) on (or below) the component.

[0047] Furthermore, it will be understood that when an element is referred to as being “coupled,” “linked,” or “connected” to another element, the elements may be directly “coupled,” “linked,” or “connected” to each other, or there may be intervening elements between them through which the element is “coupled,” “linked,” or “connected” to the other element. Furthermore, when a component is referred to as being “electrically coupled” to another component, the component may be directly connected to the other component, or there may be intervening components between them such that the component and the other component are indirectly connected to each other.

[0048] Throughout this 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 a plurality of the listed items. Unless otherwise stated, when "C to D" is stated, it means C or greater and D or less.

[0049] Figure 1 is a perspective view of a secondary battery according to some embodiments of the present disclosure. Figure 2 It is along Figure 1 Hereinafter, the structure of the secondary battery 100 according to an embodiment of the present disclosure will be described.

[0050] Reference Figure 1 and Figure 2 The secondary battery 100 may include an electrode assembly 110 , a first current collector 120 , a first terminal 130 , a second current collector 140 , a second terminal 150 , a case 160 , a first cap assembly 170 , and a second cap assembly 180 .

[0051] The electrode assembly 110 can be formed by winding or stacking a stack of a first electrode plate 111, a separator 113, and a second electrode plate 112, each of which is configured in a thin plate or film shape. When the electrode assembly 110 is a wound stack, the winding axis can be parallel to the length of the housing 160 (e.g., the y-direction). In some embodiments, the electrode assembly 110 can be a stacked electrode assembly rather than a wound one, but the shape or type of the electrode assembly 110 is not limited. In some embodiments, the electrode assembly 110 can be a Z-stack electrode assembly, in which the first and second electrode plates 111, 112 are inserted between two sides of the separator 113 and then folded (or bent) into a Z-stack. In some embodiments, the electrode assemblies 110 can be stacked such that one or more electrode assemblies 110 are adjacent to each other and housed in the housing 160. The number of electrode assemblies 110 in the housing 160 is not limited.

[0052] The first electrode plate 111 of the electrode assembly 110 may function as a negative electrode, and the second electrode plate 112 may function as a positive electrode, but vice versa.

[0053] The first electrode plate 111 can be formed by applying a first electrode active material (such as graphite and carbon) to a first electrode current collector made of a metal foil (such as copper, a copper alloy, nickel, or a nickel alloy). The first electrode plate 111 may include a first electrode tab (e.g., a first uncoated portion) 114 that is not coated with the first electrode active material. The first electrode tab may be a passage for current to flow between the first electrode plate 111 and the first current collector 120. In some embodiments, the first electrode tab may be formed by pre-cutting the first electrode plate 111 so that it protrudes to one side during manufacture, and the first electrode tab may protrude more to one side than the uncut separator 113.

[0054] The second electrode plate 112 can be formed by applying a second electrode active material (such as a transition metal oxide) to a second electrode current collector made of a metal foil (such as aluminum or an aluminum alloy). The second electrode plate 112 may include a second electrode tab (e.g., a second uncoated portion) 115 that is not coated with the second electrode active material. The second electrode tab can be a channel for current to flow between the second electrode plate 112 and the second current collector 140. In some embodiments, the second electrode tab can be formed by pre-cutting the second electrode plate 112 so that it protrudes toward the other side during manufacture, and the second electrode tab can protrude more toward the other side than the uncut separator 113.

[0055] In some embodiments, the first electrode tab may be located on the side surface at the left end of the electrode assembly 110, and the second electrode tab may be located on the side surface at the right end of the electrode assembly 110. Figure 1 and Figure 2 The left side and the right side are named according to the orientation of the secondary battery 100 in FIG. 1 , and the orientation of the secondary battery 100 may change when the secondary battery 100 is rotated left and right or up and down.

[0056] In some embodiments, the separator 113 can be placed between the first electrode plate 111 and the second electrode plate 112 to prevent or reduce short circuits therebetween while allowing lithium ions to move therebetween. The separator 113 can include polyethylene, polypropylene, or a composite film of polyethylene and polypropylene. In some embodiments, the separator 113 can be replaced with an inorganic solid electrolyte (such as a sulfide, oxide, or phosphate compound) or a gel electrolyte that does not require a liquid. In some examples, the fixing member 116 can be attached to at least a portion of the electrode assembly 110. The fixing member 116 can fix the electrode assembly 110 and insulate the electrode assembly 110. The fixing member 116 can cover a portion of the periphery of the electrode assembly 110, and multiple fixing members 116 can be attached.

[0057] As described above, the first electrode tab of the first electrode plate 111 and the second electrode tab of the second electrode plate 112 may be located at both ends of the electrode assembly 110, respectively. In some embodiments, the electrode assembly 110 may be housed in the housing 160 together with the electrolyte. In some embodiments, the electrolyte may include an organic solvent such as EC, PC, DEC, EMC, or DMC and a lithium salt such as LiPF6 or LiBF4. In some embodiments, the electrolyte may be in a liquid phase or a gel phase. In some embodiments, an inorganic solid electrolyte may be used, thereby omitting the liquid or gel electrolyte.

[0058] In addition, in the electrode assembly 110 , the first current collector 120 and the second current collector 140 may be welded and connected to first and second electrode tabs of the first and second electrode plates 111 and 112 exposed at both sides of the electrode assembly 110 , respectively.

[0059] The first current collector 120 may be made of metal and may electrically connect the first electrode plate 111 and the first terminal 130. In some embodiments, the first current collector 120 may be housed within the housing 160 and positioned between the first cap plate 171 and the electrode assembly 110. The first current collector 120 may include a first current collector plate 121 that contacts and is bonded to the first electrode tab (e.g., the first uncoated portion) of the first electrode plate 111, and a first protruding current collector plate (e.g., a first protruding current collector) 122 that contacts and is bonded to the first terminal 130. The first current collector plate 121 and the first protruding current collector plate 122 may be integrally formed or separately provided. The first current collector 120 may be made of copper or a copper alloy.

[0060] The first current collector plate 121 may extend in a first direction (e.g., x-direction) that is a length direction of the first cap plate 171 on one surface of the electrode assembly 110 (e.g., may extend primarily in the first direction (e.g., x-direction)) and may have a generally plate shape. The first current collector plate 121 may have the same polarity as the first electrode plate 111 by being bonded to the first electrode plate 111 by welding in a state of contact with a first electrode tab exposed at one end of the electrode assembly 110.

[0061] In some embodiments, a space may be defined inside (or below) the first current collector 120. A first adhesive member (eg, a first adhesion member) 174 may be disposed in this space to fix the separator of the electrode assembly 110.

[0062] The first protruding current collector plate 122 may be in contact with an outer surface of the first current collector plate 121 , and may be in contact with and welded to an inner surface of the first terminal 130 .

[0063] First terminal 130 is made of metal and may contact and be welded to first protruding collector plate 122 and then electrically connected to first protruding collector plate 122. According to some embodiments, first terminal 130 may include a first terminal plate 131 and a first terminal through-hole 132.

[0064] The first terminal 130 may be made of aluminum or an aluminum alloy. In some embodiments, when the first terminal 130 is a negative electrode, the first terminal 130 and the first current collector 120 may be made of the same metal. However, in some embodiments, the first terminal 130 and the first current collector 120 may be made of different metals. In some embodiments, a covering sheet may be provided between the first terminal 130 and the first current collector 120. When the first terminal 130 and the first current collector 120 are made of different metals, the covering sheet may bond the first terminal 130 and electrically connect it to the first current collector 120. The covering sheet may be a sheet in which an aluminum sheet and a copper sheet are bonded by thermocompression. For example, the covering sheet may be a sheet in which aluminum having a thickness of approximately 2T and copper having a thickness in the range of approximately 0.5T to approximately 0.7T are bonded by thermocompression. The aluminum sheet of the covering sheet may be bonded to the first terminal 130 by welding, and the copper sheet may be bonded to the first current collector 120 by welding.

[0065] The first terminal plate 131 may be located outside or above the first cover plate 171. In some embodiments, the first terminal through-hole 132 may extend inward from the outer surface of the first terminal plate 131. The thickness of the region of the first terminal plate 131 where the first terminal through-hole 132 is provided may be smaller than the thickness of each of the other regions.

[0066] In some embodiments, a first insulating gasket 172 may be further disposed between the first terminal plate 131 and the first cover plate 171. In some embodiments, a first sealing gasket 173 may be further disposed between the outer surface of the first terminal plate 131 and the first cover plate 171 to seal the space between the first terminal 130 and the first cover plate 171.

[0067] According to some embodiments, first terminal plate 131 may contact and be coupled to first protruding collector plate 122 of first current collector 120 at one surface. In some embodiments, first terminal plate 131 of first terminal 130 may be exposed and protrude from the outside of first cap plate 171.

[0068] The second current collector 140 may be made of metal and may electrically connect the second electrode plate 112 and the second terminal 150. The second current collector 140 may be provided as a metal plate and may include a second current collector plate 141 that contacts and is coupled to the second electrode tab of the second electrode plate 112 and a second protruding current collector plate 142 that contacts and is coupled to the second terminal 150. In some embodiments, the second current collector 140 may be coupled to the electrode assembly 110 and the second terminal 150 in a shape symmetrical to the first current collector 120 relative to the electrode assembly 110. In some embodiments, the second current collector 140 may be made of aluminum or an aluminum alloy.

[0069] The second terminal 150 may be made of metal and may be electrically connected to the second current collector 140. In some embodiments, the second terminal 150 may include a second terminal plate 151 having a second terminal through-hole (eg, a second terminal opening) 152.

[0070] In some embodiments, the second terminal plate 151 may be located outside (e.g., above) the second cover plate 181. In some embodiments, a second insulating gasket 182 may be positioned between the second terminal plate 151 and the second cover plate 181. In some embodiments, a second sealing gasket 183 may be positioned between the second terminal plate 151 and the second cover plate 181.

[0071] The second terminal 150 may have the same shape and structure as the first terminal 130. The second terminal 150 may be coupled to the electrode assembly 110 via the second current collector 140 in a shape symmetrical to the first terminal 130 relative to the electrode assembly 110. In some embodiments, the second terminal 150 may be made of aluminum or an aluminum alloy. In some embodiments, because the second terminal 150 and the second current collector 140 are made of the same metal, the second terminal 150 and the second current collector 140 may be directly coupled to each other by welding.

[0072] The case 160 may have a hollow substantially rectangular shape with openings 161 , 162 defined at both sides (or ends), and the electrode assembly 110 may be inserted into the case 160 through the openings 161 , 162 in a state where it is coupled to the first and second current collectors 120 , 140 .

[0073] The housing 160 may have two long side surfaces in a rectangular shape, the two long side surfaces connecting (or extending between) a top surface and a bottom surface extending in a second direction (e.g., the y-direction) as the longitudinal direction, and extending in the second direction (e.g., the y-direction). In the housing 160, the top and bottom surfaces and the two long side surfaces may be integral with each other (e.g., may be formed integrally with each other).

[0074] The housing 160 may have a vent hole (e.g., a vent opening) extending through one of the long side surfaces. A safety vent may be installed in the vent hole in the housing 160. In some embodiments, the safety vent may be provided with (or may be provided with) a notch that is thinner than other areas so as to open (or rupture) at a set (or reference) pressure.

[0075] The first cover assembly 170 may be coupled to the left opening 161 in the housing 160. In some embodiments, the first cover assembly 170 may include a first cover plate 171, a first insulating gasket 172, a first sealing gasket 173, and a first adhesive member (eg, a first adhesion member) 174.

[0076] The first cap plate 171 may have a flat rectangular plate shape to seal the left opening 161 in the case 160. The first cap plate 171 may have a first terminal through-hole (e.g., a first terminal opening) 132 and an electrolyte injection port extending between its outer and inner surfaces. The protrusions of the first protruding current collector plate 122 may pass through the first terminal through-hole 132 in the first cap plate 171 and may be coupled to the first terminal plate 131. In some embodiments, after the first cap plate 171 is coupled to the case 160 and the electrolyte is injected into the case 160, the electrolyte injection port may be sealed by a stopper 176.

[0077] The first insulating gasket 172 may be disposed between the inner surface of the first cover plate 171 and the first terminal plate 131. The first insulating gasket 172 may be in close contact with the inner surface of the first cover plate 171, and may also be in close contact with the first sealing gasket 173. The first insulating gasket 172 may be made of an insulating material to insulate the first cover plate 171 and the first terminal plate 131 from each other.

[0078] In some embodiments, the first sealing gasket 173 may be made of an insulating material and may be disposed between the first cap plate 171 and the first terminal plate 131 or on an outer surface of the first terminal plate 131 to seal the gap between the first cap plate 171 and the first terminal plate 131. The first sealing gasket 173 may prevent or reduce the penetration of external contaminants (such as moisture) into the secondary battery 100 or the leakage of the electrolyte contained in the secondary battery 100 to the outside. The first sealing gasket 173 may be manufactured together with the first insulating gasket 172 using an insert molding method.

[0079] In some embodiments, the first sealing gasket 173 can be integrally formed with the first insulating gasket 172 by injection molding and can be interposed between the first terminal 130 and the first cap plate 171. In some embodiments, the first cap plate 171 can be electrically separated (e.g., electrically insulated) from the first terminal 130 and the first protruding current collector plate 122 by the first insulating gasket 172 and the first sealing gasket 173.

[0080] Furthermore, in some examples, the secondary battery 100 may include a first insulating plate 191 and a second insulating plate 192. The first insulating plate 191 may be positioned between the first current collector 120 and the first cap plate 171 to provide electrical insulation between the first current collector 120 and the first cap plate 171. The second insulating plate 192 may be positioned between the second current collector 140 and the second cap plate 181 to provide electrical insulation between the second current collector 140 and the second cap plate 181. The first insulating plate 191 and the second insulating plate 192 may be made of a plastic material having high electrical insulation properties, such as polyamide (PA), polyethylene (PE), or polypropylene (PP).

[0081] The second cover assembly 180 can be coupled to the right opening 162 in the housing 160. In some embodiments, the second cover assembly 180 can include a second cover plate 181, a second insulating gasket 182, a second sealing gasket 183, and a second adhesive member (e.g., a second adhesive member) 184. The second cover assembly 180 can have the same shape and structure as the first cover assembly 170. In some embodiments, the combined shape and structure of the second cover assembly 180 and the second terminal 150 can be the same as the combined shape and structure of the first cover assembly 170 and the first terminal 130, respectively. However, the combined shape of the second cover assembly 180 and the second terminal 150 can be symmetrical relative to the combined shape of the housing 160, the first cover assembly 170, and the first terminal 130.

[0082] In the secondary battery 100, the first cap assembly 170 coupled to the first terminal 130 can be coupled to an opening on one side of the housing 160, and the second cap assembly 180 coupled to the second terminal 150 can be coupled to an opening on the other side (e.g., the opposite side) of the housing 160. Therefore, the first terminal 130 and the second terminal 150 can be located on opposite sides of the housing 160 with the housing 160 as the center. The secondary battery 100 can be provided with the first terminal 130 and the second terminal 150 on both sides thereof. Therefore, if multiple secondary batteries 100 are combined in the form of a module, a cooling member can be coupled to each of the upper and lower regions of the housing 160. In some embodiments, degradation of the secondary battery 100 can be reduced by improving cooling performance.

[0083] For example, in a battery module, when long side surfaces of a plurality of secondary batteries 100 are arranged to face each other, the first terminal 130 and / or the second terminal 150 respectively exposed at both sides of each secondary battery 200 may be electrically connected to each other.

[0084] In some embodiments, the first terminal 130 and the second terminal 150 may be disposed on both sides of the secondary battery 100. Therefore, if a plurality of secondary batteries are combined together in a module, since the charge / discharge current flows along each terminal on both sides, the two terminals may be disposed on opposite sides to prevent or reduce potential degradation of the electrode assembly 110, compared to a case where the charge / discharge current flows along the two terminals on one side (e.g., the same side) of the housing. In some embodiments, if a plurality of secondary batteries 100 are combined together in a module, since the terminals are connected to each other on both sides, space utilization may be improved.

[0085] Figure 3A 、 Figure 3B and Figure 3Cis a diagram for explaining a squeezing operation of a method for manufacturing a secondary battery according to some embodiments of the present disclosure, Figure 4 is a diagram showing a state of a separator before being bonded to a current collector according to some embodiments of the present disclosure, Figure 5 is a diagram showing a state of a separator after being bonded to a current collector according to some embodiments of the present disclosure, Figure 6 is a diagram illustrating a state after a squeezing operation according to some embodiments of the present disclosure.

[0086] At the same time, in the structure of the current collectors 120 and 140 according to some embodiments, there may be some gap between the diaphragm 113 and the current collector plates 121 and 141 to ensure weldability and prevent or reduce damage to the diaphragm. Due to the gap between the diaphragm 113 and the current collector plates 121 and 141, capacity loss may occur. Therefore, in some embodiments, a diaphragm extrusion design can be applied, and the diaphragm 113 can be extruded to reduce the free space and gap within the structure while the current collector plates 121 and 141 are welded and fixed to the electrode assembly 110. The diaphragm extrusion design can refer to including a diaphragm extrusion margin space at both ends of the diaphragm 113 where the current collector plates 121 and 141 are fixed. In some embodiments, the diaphragm extrusion margin space is designed to be squeezed when the current collector plates 121 and 141 are fixed, and specific areas at both ends of the diaphragm 113 can be different from the parts that are not squeezed even when squeezed in terms of physical structure, arrangement method, material, manufacturing process or coating treatment. In some embodiments, the diaphragm 113 may be composed of a space for diaphragm extrusion and a portion that is not squeezed even when squeezed. In other words, the capacity can be increased by using a diaphragm extrusion design. Furthermore, according to some embodiments, when the diaphragm 113 is squeezed, the flow of the electrode assembly 110 within the housing is suppressed, thereby eliminating the flow that may occur due to the lack of a structure within the housing to retain or support the electrode assembly 110.

[0087] In the following, reference will be made to Figures 3A to 6 A method for manufacturing a secondary battery in which the separator 113 is compressed is described in more detail. Meanwhile, since both sides of the secondary battery 100 have the same structure, the following description will be made based on the first current collector plate 121 .

[0088] Reference Figures 3A to 3CIn some examples, after the first current collector plate 121 is electrically connected to the first electrode plate 111 of the electrode assembly 110, the first current collector plate 121 may be squeezed by a set amount. Here, the separator squeeze margin space of the separator 113 that protrudes outward from the electrode assembly 110 relative to the first electrode plate 111 may be squeezed in the direction of the electrode assembly 110. That is, according to some embodiments, the separator 113 and the first current collector plate 121 may be brought into close contact with each other so that there is no gap between the separator 113 and the first current collector plate 121. Here, the side surface of the separator 113 may be squeezed based on the length direction of the electrode assembly 110. In addition, in some examples, after the first current collector plate 121 is electrically connected to the first electrode plate 111, the first current collector plate 121 may be squeezed by bonding the first insulating plate 191 to one side of the first current collector plate 121 and squeezing the first insulating plate 191.

[0089] In addition, according to some embodiments, after the first current collector plate 121 is squeezed to a set amount, the electrode assembly 110 may be internally insulated. Here, the insulating member 190 may be attached to at least one side of the electrode assembly 110 and the first insulating plate 191. That is, in some examples, internal insulation may be performed while the separator squeeze structure is applied.

[0090] Figure 3A The figure shows the state where the separator 113 is joined to the current collector plates 121 and 141 by welding before extrusion. Figure 3B 1 and 2 show the state where the insulating plates 191 and 192 are bonded to the outside of the current collector plates 121 and 141 respectively before extrusion. Figure 3C A state in which internal insulation is performed and the insulating member 190 is attached after extrusion is shown. Figure 3A The total width W1 in , which corresponds to the width of the separator 113 plus the gap between the separator 113 and the current collector plates 121 , 141 and the thickness of the current collector plates 121 , 141 , may be, for example, 239.9 mm. Figure 3B The total width W2 corresponding to the total width W1 plus the thickness of the insulating plates 191 and 192 may be, for example, 254.9 mm. Figure 3C The total width W3 corresponding to the width after the total width W2 is squeezed can be, for example, 252.0 mm. Here, by squeezing according to the set squeezing amount, the gap between the diaphragm 113 and the current collector plates 121 and 141 is eliminated, and the gap between the diaphragm 113 and the current collector plates 121 and 141 can be reduced. Figure 3B In some examples, the length of the changed diaphragm squeeze allowance after squeezing may be 38% to 42% of the length of the initial diaphragm squeeze allowance.

[0091] According to some embodiments, the set squeezing amount may be set based on the length of the initial gap between the first current collector plate 121 and the separator 113 and the length of the initial separator squeezing margin space between the separator 113 and the first electrode plate 111. The length of the initial gap between the first current collector plate 121 and the separator 113 may refer to the length before the squeezing operation is performed. For example, the set squeezing amount may be set to 0.7% to 1.2% of the length between the outer surface of the first current collector plate 121 and the outer surface of the second current collector plate 141 coupled to the other side of the electrode assembly 110 before the squeezing operation.

[0092] In addition, the length of the initial diaphragm squeeze margin space between the diaphragm 113 and the first electrode plate 111 may also refer to the length before the squeezing operation is performed. That is, after the squeezing operation, the length of the initial diaphragm squeeze margin space may be reduced. That is, after the squeezing operation, the initial design width of the diaphragm 113 may be reduced. The initial design width of the diaphragm 113 may be the sum of the length of the portion that is not squeezed even when squeezed and the length of the initial diaphragm squeeze margin space. For example, the length of the initial diaphragm squeeze margin space may be set to 0.84% ​​to 0.86% of the initial design width of the diaphragm 113.

[0093] Reference Figure 4 The initial diaphragm squeeze margin space A can be set to the length obtained by subtracting the length B between the end of the portion of the diaphragm 113 that is not squeezed even when squeezed and the protruding position of the first electrode plate 111, and the length C between the protruding position of the first electrode plate 111 and the aligned position of the first electrode plate 111 from the length L between the end of the diaphragm squeeze margin space of the diaphragm 113 and the aligned position of the first electrode plate 111 (A=LBC). Here, the area corresponding to the length C between the protruding position of the first electrode plate 111 and the aligned position of the first electrode plate 111 can be the reverse prevention area for the positive electrode position and the negative electrode position. In addition, the area corresponding to the length B between the end of the diaphragm 113 and the protruding position of the first electrode plate 111 can be the short circuit prevention area for the positive and negative electrodes.

[0094] Reference Figure 5 and Figure 6 In some examples, the initial gaps G1 and G3 between the separator 113 and the first current collector plate 121 before extrusion can be, for example, 0.85 mm. Furthermore, according to some embodiments, the initial width G2 of the separator 113 before extrusion can be 237.2 mm. Here, the initial design width of the separator 113 can be the sum of the length of the portion that would not be extruded even if extruded (e.g., 235.2 mm) and the length of the initial separator extrusion margin (e.g., 2 mm). The length D1 of one side of the initial separator extrusion margin can be, for example, 1 mm.

[0095] According to some embodiments, after compression, the separator 113 and the first current collector plate 121 can be in close contact with each other without a gap. Furthermore, after compression, the width G4 of the separator 113 can be, for example, 236.0 mm. Here, the width of the separator 113 can be the sum of the length of the portion that remains uncompressed even when compressed (e.g., 235.2 mm) and the length of the pressurized separator margin (e.g., 0.8 mm). The length D2 of one side of the pressurized separator margin can be, for example, 0.4 mm.

[0096] Therefore, the separator 113 can be squeezed by compression, reducing the gap length between the separator 113 and the first current collector plate 121 from 0.85 mm to 0 mm. Furthermore, by squeezing the first current collector plate 121, the separator squeeze margin length can be reduced from 1.0 mm to 0.4 mm (D1 > D2). In other words, in some examples, the amount of squeezing on one side can be 0.85 mm + 0.6 mm = 1.45 mm. Consequently, the separator width can be reduced from 237.2 mm to 236.0 mm (G2 > G4).

[0097] That is, according to some embodiments, the capacity loss caused by the gap between the separator 113 and the current collector plates 121, 141 required in the welding process can be overcome by the separator extrusion design. In addition, in some examples, the stack flow inside the case can be suppressed by the extrusion design.

[0098] Figure 7 is a perspective view of an example of a battery module. Figure 8A and Figure 8B A perspective view illustrating an example of a battery pack is shown. Figure 9A and Figure 9B Perspective and side views of examples of vehicle bodies and vehicle components are shown.

[0099] In some examples, a battery pack according to one or more embodiments includes at least one battery module and a battery pack housing having an accommodation space in which the at least one battery module is accommodated.

[0100] A battery module may include multiple battery cells and a module housing. The battery cells may be housed within the module housing in a stacked form (or stacked arrangement or configuration). Each battery cell may have a positive electrode terminal and a negative electrode terminal and, depending on the battery shape, may be round, prismatic, or pouch-shaped. Throughout this specification, a battery cell may also be referred to as a secondary battery, battery, or cell.

[0101] In a battery pack, a single cell stack may constitute a stacked module instead of a battery module. The single cell stack may be housed in a housing space of a battery pack case, or in a housing space partitioned by a frame, a partition wall, or the like.

[0102] Battery cells generate a large amount of heat during charging and discharging. This heat accumulates in the battery cells, accelerating their degradation. Therefore, the battery pack may further include a cooling member to remove the generated heat and thereby suppress degradation of the battery cells. The cooling member may be provided at the bottom of the storage space containing the battery cells, but is not limited thereto and may be provided at the top or side, depending on the battery pack.

[0103] Battery cells can be configured so that exhaust gases generated within the battery cells during abnormal operating conditions (also known as thermal runaway or thermal events) are discharged to the exterior of the battery cells. A battery pack or module can include an exhaust port for discharging exhaust gases to prevent or reduce damage to the battery pack or module.

[0104] A battery pack may include batteries and a battery management system (BMS) for managing the batteries. The BMS may include a detection device, a balancing device, and a control device. A battery module may include multiple battery cells connected in series and / or in parallel. Battery modules may be connected in series and / or in parallel.

[0105] The detection device can detect the battery status (e.g., voltage, current, temperature, etc.) and output status information indicating the battery status. The detection device can detect the voltage of each cell or each battery module that constitutes the battery. The detection device can detect the current flowing through each battery module that constitutes the battery pack. The detection device can also detect the temperature of the cell and / or module at at least one point in the battery and / or the ambient temperature.

[0106] The balancing device can perform balancing operations on the battery module and / or the cells constituting the battery module. The control device can receive status information of the battery module (e.g., voltage, current, temperature, etc.) from the detection device. The control device can monitor and calculate the status of the battery module (e.g., voltage, current, temperature, state of charge (SOC), life (state of health (SOH)), etc.) based on the status information received from the detection device. In addition, based on the monitored status information, the control device can perform control functions (e.g., temperature control, balancing control, charge / discharge control, etc.) and protection functions (e.g., over-discharge, over-charge, over-current protection, short circuit, fire extinguishing function, etc.). In addition, the control device can perform wired or wireless communication functions with external devices of the battery pack (e.g., a higher-level controller or vehicle, charger, power conversion system, etc.).

[0107] The control device can control the charge / discharge operation and protection operation of the battery. To this end, the control device can include a charge / discharge control unit, a balance control unit and / or a protection unit.

[0108] A battery management system is a system that monitors the battery status and performs diagnostic and control, communication, and protection functions, and can calculate the charge / discharge state, calculate the battery life or state of health (SOH), cut off the battery power as needed (e.g., relay control), control thermal management (e.g., cooling, heating, etc.), perform high-voltage interlock functions, and / or can detect and / or calculate insulation and short circuit conditions.

[0109] A relay may be a mechanical contactor that is turned on and off by the magnetic force of a coil or a semiconductor switch such as a metal oxide semiconductor field effect transistor (MOSFET).

[0110] The relay control has a function of cutting off the power supply from the battery if (or when) a problem occurs in the vehicle and the battery system, and may include one or more relays and a pre-charge relay at the positive terminal and the negative terminal, respectively.

[0111] During pre-charge control, there is a risk of inrush current flowing through the high-voltage capacitors on the inverter's input side when connecting a battery load. Therefore, to prevent or reduce inrush current when starting the vehicle, a pre-charge relay can be operated before connecting the main relay, and a pre-charge resistor can be connected.

[0112] The high-voltage interlock is a circuit that uses a small signal to detect whether all high-voltage components of the entire vehicle system are connected, and can have the function of forcibly disconnecting the relay if (or when) a disconnection occurs at one position on the entire circuit.

[0113] Figure 7 2 is a perspective view of an example of a battery module 20. Figure 7 According to one or more embodiments of the present disclosure, a battery module 20 includes electrode units (or "terminal portions") 12-1, 12-2, a plurality of battery cells 10 arranged in one direction, a connection tab 22 connecting a battery cell 10a to an adjacent battery cell 10b, and a protection circuit module 23 having one end connected to the connection tab 22. The protection circuit module 23 may include a battery management system (BMS). Furthermore, the connection tab 22 may include a main portion that contacts the electrode units 12-1, 12-2 between adjacent battery cells 10a, 10b, and an extension portion that extends from the main portion and connects to the protection circuit module 23. The connection tab 22 may be, for example, a bus bar.

[0114] Each battery cell 10 may include a battery case, an electrode assembly received (or housed) in the battery case, and an electrolyte. The electrode assembly and the electrolyte undergo an electrochemical reaction to store and release (e.g., generate) energy. Terminal portions 12-1, 12-2 electrically connected to the connecting tab 22 and an exhaust port 13-4 serving as an exhaust passage for gases generated inside the battery case may be provided on one side (e.g., the upper side) of the battery cell 10. The terminal portions 12-1, 12-2 of the battery cell 10 may be a positive electrode terminal 12-1 and a negative electrode terminal 12-2 having different polarities from each other, and the terminal portions 12-1, 12-2 of adjacent battery cells 10a and 10b may be electrically connected to each other in series or in parallel via the connecting tab 22, which will be described in more detail below. Although the series connection has been described as an example, the connection structure is not limited thereto, and various connection structures may be employed as desired or required. In addition, the number and arrangement of the battery cells are not limited to Figure 7 The structures shown in FIG. 5 are for reference only and may be changed as desired or necessary.

[0115] A plurality of battery cells 10 can be arranged in one direction (e.g., can be stacked in one direction) such that the wide surfaces of the battery cells 10 face each other, and the plurality of battery cells 10 can be secured by housings 26-1, 26-2, 26-3, and 26-4. The housings 26-1, 26-2, 26-3, and 26-4 can include a pair of end plates 26-1 and 26-2 facing the wide surfaces of the battery cells 10, and a side plate 26-3 and a bottom plate 26-4 connecting the pair of end plates 26-1 and 26-2 to each other. The side plate 26-3 can support the side surfaces of the battery cells 10, and the bottom plate 26-4 can support the bottom surface of the battery cells 10. In addition, the pair of end plates 26-1 and 26-2, the side plate 26-3, and the bottom plate 26-4 can be connected by bolts 26-5 and / or any other suitable fastening members and methods known to those of ordinary skill in the art.

[0116] The protection circuit module (PCM) 23 may include electronic components and protective circuitry mounted thereon, and may be electrically connected to the connection tabs 22 , as described in greater detail later. The protection circuit module 23 includes a first protection circuit module 23a and a second protection circuit module 23b at different locations, extending along the direction in which the battery cells 10 are arranged. The first and second protection circuit modules 23a, 23b may be spaced apart from each other at an appropriate interval (e.g., a set or predetermined interval) and arranged parallel to each other, each electrically connected to an adjacent connection tab 22. For example, the first protection circuit module 23a may extend along the direction in which the battery cells 10 are arranged on one side of the upper portion of the battery cells 10, while the second protection circuit module 23b may extend along the other side of the upper portion of the battery cells 10. The second protection circuit module 23b may be spaced apart from the first protection circuit module 23a at an appropriate interval (e.g., a set or predetermined interval), with the vent 13 - 4 positioned therebetween, but the second protection circuit module 23b may be arranged parallel to the first protection circuit module 23a. In this manner, the two protection circuit modules are spaced side by side along the direction in which the multiple battery cells 10 are arranged, thereby reducing or minimizing the area of ​​the printed circuit board (PCB) that constitutes the protection circuit modules. By configuring the protection circuit modules as two separate protection circuit modules, unnecessary PCM area can be reduced or minimized. Furthermore, the first protection circuit module 23a and the second protection circuit module 23b can be connected to each other via a conductive connecting member 25. One side of the conductive connecting member 25 is connected to the first protection circuit module 23a, and the other side is connected to the second protection circuit module 23b, thereby electrically connecting the two protection circuit modules 23a and 23b.

[0117] The joining may be performed by any of welding, resistance welding, laser welding, projection welding, and / or any other suitable joining method known to those of ordinary skill in the art.

[0118] Furthermore, the connecting member 25 may be, for example, an electrical wire. Furthermore, the connecting member 25 may be made of an elastic or flexible material. The connecting member 25 may be used to check and manage the voltage, temperature, and / or current of the multiple battery cells 10. For example, information received by the first protection circuit module from a connecting tab adjacent to the first protection circuit module (such as voltage, current, and / or temperature) and information received from a connecting tab adjacent to the second protection circuit module (such as voltage, current, and / or temperature) may be integrated and managed by the protection circuit modules via the connecting member 25.

[0119] In addition, when the battery cell 10 expands, the impact can be absorbed by the elasticity or flexibility of the connecting member 25, thereby preventing or reducing damage to the first protection circuit module 23a and the second protection circuit module 23b. In addition, the shape and structure of the connecting member 25 are not limited to Figure 7 The shape and structure shown in .

[0120] As described above, because the protection circuit module 23 is set as the first protection circuit module 23a and the second protection circuit module 23b, the area of ​​the PCB constituting the protection circuit module can be reduced or minimized, and the space inside the battery module can be ensured, thereby improving work efficiency by facilitating the fastening work for connecting the connecting terminal 22 and the protection circuit module 23 and the maintenance work if (when) an abnormality is detected in the battery module.

[0121] Figure 8A and Figure 8B A perspective view of an example of the battery pack 30 is shown.

[0122] The battery pack 30 may include a plurality of battery modules 20 and a housing 31 for accommodating the plurality of battery modules 20. For example, the housing 31 may include a first housing 31-1 and a second housing 31-2 coupled in opposite directions by the plurality of battery modules 20. The plurality of battery modules 20 may be electrically connected to each other using bus bars 25-1, and the plurality of battery modules 20 may be electrically connected to each other in a series / parallel or mixed series-parallel method to obtain a desired (e.g., required) electrical output.

[0123] Figure 9A and Figure 9B Perspective and side views of examples of a vehicle body 40 and vehicle components are shown.

[0124] exist Figure 9A In the embodiment of the present invention, the battery pack 30 may include a battery pack cover 30-1 as part of the underbody 41 and a battery pack frame 30-2 located below the underbody 41. In some examples, the battery pack cover 30-1 may correspond to the first outer shell 31-1, and the battery pack frame 30-2 may correspond to the second outer shell 31-2. The battery pack frame 30-2 and the battery pack cover 30-1 may be integrally formed with the vehicle floor 42. The underbody 41 separates the interior and exterior of the vehicle, and the battery pack frame 30-2 may be located outside the vehicle.

[0125] Reference Figure 9B , the vehicle 50 may be formed by combining additional components such as a hood 51 at the front of the vehicle and fenders 52 located at the front and rear of the vehicle, respectively, to the vehicle body 40 .

[0126] The vehicle 50 may include a battery pack 30 including a pack cover 30 - 1 and a pack frame 30 - 2 , and the battery pack 30 may be coupled to a vehicle body 40 .

[0127] Meanwhile, as the positive electrode active material, a compound capable of reversibly intercalating / deintercalating lithium (eg, a lithiated intercalation compound) can be used. For example, at least one composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0128] The composite oxide may be a lithium transition metal composite oxide, and examples thereof may include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0129] For example, a compound represented by any one of the following formulae may be used: For example, a compound represented by any one of the following formulae may be used: Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2- b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b-c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoGb O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3(0≤f≤2);Li a FePO4 (0.90≤a≤1.8).

[0130] In the above formula: A is Ni, Co, Mn or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element or a combination thereof; D is O, F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; L 1 It is Mn, Al or a combination thereof.

[0131] A positive electrode for a lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may include a positive electrode active material and may further include a binder and / or a conductive material.

[0132] Based on 100 wt % of the positive electrode active material layer, the content of the positive electrode active material is in the range of about 90 wt % to about 99.5 wt %, and based on 100 wt % of the positive electrode active material layer, the contents of the binder and the conductive material are respectively in the range of about 0.5 wt % to about 5 wt %.

[0133] The current collector may be aluminum (Al), but is not limited thereto.

[0134] The negative electrode active material may include a substance capable of reversibly intercalating / deintercalating lithium ions, lithium metal, a lithium metal alloy, a substance capable of doping and dedoping lithium, or a transition metal oxide.

[0135] The material capable of reversibly intercalating and deintercalating lithium ions may be a carbon-based negative electrode active material, which may include, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon may include graphite (such as natural graphite or artificial graphite), and examples of amorphous carbon may include soft carbon, hard carbon, pitch carbide, mesophase pitch carbide, sintered coke, and the like.

[0136] As a substance capable of doping and undoping lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material can be used. The Si-based negative electrode active material can be silicon, a silicon-carbon composite, SiO x (0 < x < 2), a Si-based alloy, or a combination thereof.

[0137] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to some embodiments, the silicon-carbon composite can be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0138] The silicon-carbon composite can also include crystalline carbon. For example, the silicon-carbon composite can include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0139] The negative electrode for a lithium secondary battery can include a current collector and a negative electrode active material layer located on the current collector. The negative electrode active material layer can include a negative electrode active material and can also include a binder and / or a conductive material.

[0140] For example, the negative electrode active material layer can include about 90 wt% to about 99 wt% of the negative electrode active material, about 0.5 wt% to about 5 wt% of the binder, and about 0 wt% to about 5 wt% of the conductive material.

[0141] As the binder, a non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used. When an aqueous binder is used as the negative electrode binder, a cellulose-based compound capable of imparting viscosity can be further included.

[0142] As the negative electrode current collector, one selected from a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a polymer substrate coated with a conductive metal, and a combination thereof can be used.

[0143] The electrolyte for a lithium secondary battery can include a non-aqueous organic solvent and a lithium salt.

[0144] The non-aqueous organic solvent acts as a medium through which ions participating in the battery electrochemical reaction can move.

[0145] The non-aqueous organic solvent can be a carbonate solvent, an ester solvent, an ether solvent, a ketone solvent, an alcohol solvent, an aprotic solvent, and can be used alone or in combination of two or more.

[0146] In addition, when using a carbonate solvent, a mixture of a cyclic carbonate and a chain carbonate can be used.

[0147] Depending on the type of lithium secondary battery, a separator may be present between a first electrode plate (e.g., a negative electrode) and a second electrode plate (e.g., a positive electrode). As the separator, polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof may be used.

[0148] The separator may include a porous substrate and a coating layer including an organic material, an inorganic material, or a combination thereof on one or both surfaces of the porous substrate.

[0149] The organic substance may include a polyvinylidene fluoride-based polymer or a (meth)acrylic polymer.

[0150] The inorganic material may include inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but is not limited thereto.

[0151] The organic material and the inorganic material may be mixed in one coating layer, or may be in the form of a coating layer containing an organic material and a coating layer containing an inorganic material being laminated on each other.

[0152] As described above, according to some embodiments of the present disclosure, a method for manufacturing a secondary battery and a secondary battery manufactured using the method are provided, in which method, by performing a squeezing operation to ensure close contact between the collector plate and the diaphragm, the capacity can be relatively increased by ensuring the space inside the shell, and the flow of the electrode assembly inside the shell can be suppressed.

[0153] However, aspects and features of the present disclosure are not limited to the above-mentioned aspects and features, and those skilled in the art will clearly understand other aspects and features not explicitly described herein through the description of the exemplary embodiments of the present disclosure.

[0154] Although the present disclosure has been described with reference to the embodiments and the accompanying drawings showing aspects of the embodiments, the present disclosure is not limited thereto. Various modifications and changes may be made by those skilled in the art within the scope of the technical spirit of the present disclosure and the claims and their equivalents.

Claims

1. A method for manufacturing a secondary battery, the method comprising the following steps: electrically connecting a first current collector plate to a first electrode plate of an electrode assembly, the electrode assembly comprising: the first electrode plate; a second electrode plate; and a separator between the first electrode plate and the second electrode plate, the separator comprising a separator compression margin space and a portion that is not compressed even when compressed; pressing the first current collector plate with a set pressing amount in a direction of the electrode assembly to press at least a portion of the separator pressing margin space of the separator protruding outward from the electrode assembly relative to the first electrode plate; and Perform internal insulation treatment, The squeezing amount is set based on the length of the initial gap between the first current collector plate and the separator and the length of the initial separator squeezing margin space between the separator and the first electrode plate.

2. The method according to claim 1, wherein The step of pressing the first current collector plate includes bringing the separator and the first current collector plate into close contact with each other such that there is no gap therebetween.

3. The method according to claim 1, wherein The initial diaphragm extrusion margin space is set to a length obtained by subtracting the length between the end of the portion of the diaphragm that is not squeezed even when squeezed and the protruding position of the first electrode plate and the length between the protruding position of the first electrode plate and the alignment position of the first electrode plate from the length between the end of the diaphragm extrusion margin space of the diaphragm and the alignment position of the first electrode plate.

4. The method according to claim 3, wherein: A region corresponding to a length between the protruding position of the first electrode plate and the aligned position of the first electrode plate is a reversal prevention region of a positive electrode position and a negative electrode position.

5. The method according to claim 3, wherein A region corresponding to a length between the end portion of the separator and the protruding position of the first electrode plate is a positive-negative electrode short-circuit prevention region.

6. The method according to claim 1, wherein After the first current collector plate is compressed, the length of the initial separator compression margin space is reduced.

7. The method according to claim 1, wherein After the first current collector plate is pressed, the length of the separator is reduced from the initial design width. 8 . The method of claim 1 , after electrically connecting the first current collector plate to the first electrode plate, coupling a first insulating plate to one side of the first current collector plate.

9. The method according to claim 8, wherein The step of performing the internal insulation process includes attaching an insulation member to at least one side of the electrode assembly and the first insulation plate. 10 . The method according to claim 1 , further comprising pressing a side surface of the separator based on a length direction of the electrode assembly.

11. The method according to claim 1, wherein The set pressing amount is set to 0.7% to 1.2% of the length between the outer surface of the first current collector plate before pressing the first current collector plate and the outer surface of the second current collector plate coupled to the other side of the electrode assembly.

12. The method according to claim 1, wherein The length of the initial diaphragm squeeze margin space is set to 0.84% ​​to 0.86% of the initial design width of the diaphragm.

13. The method according to claim 1, wherein The length of the changed diaphragm crush allowance space after the crushing is 38% to 42% of the length of the initial diaphragm crush allowance space. 14 . A secondary battery manufactured by the method for manufacturing a secondary battery according to claim 1 .

15. The secondary battery according to claim 14, wherein The end portion of the separator and the first current collector plate are in close contact with each other without a gap.

16. The secondary battery according to claim 14, wherein At least a portion of the first current collector plate is coupled to the separator crush allowance space of the separator.

17. The secondary battery according to claim 14, comprising: a housing, accommodating the electrode assembly and the first current collector plate, and having openings on both sides; a first cover plate, sealing an opening on one side of the housing; as well as A first terminal is electrically connected to the first current collector plate and is exposed to the outside of the first cap plate. 18 . The secondary battery of claim 17 , further comprising a first protruding current collector plate connected to an outer surface of the first current collector plate and contacting and bonded to an inner surface of the first terminal.

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