Electrode assembly wherein separator is folded

Abstract

The present invention provides a development view of a separator stacked together with a first electrode and a second electrode, and a structure of an electrode assembly including the separator. According to the present invention, a first region and a second region, which are alternately repeated and connected in series, are defined in the development view of the separator, and the separator is folded so that the first region and the second region alternately and repeatedly overlap each other in a thickness direction.

Description

Electrode assembly with folded separator

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0114303, dated August 26, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a structure of an electrode assembly in which a separator is continuously folded to surround an electrode.

[0003] Secondary batteries, which have high applicability according to product group and electrical characteristics such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electrical power sources.

[0004] These secondary batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency because they not only have the primary advantage of drastically reducing the use of fossil fuels, but also have the advantage of producing no byproducts from energy use.

[0005] Currently, the types of secondary batteries widely used include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, i.e., unit battery cells, is approximately 2.5 V to 4.5 V. Therefore, when a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Furthermore, depending on the charge / discharge capacity required for the battery pack, a number of battery cells are connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack and the electrical connection type can be set in various ways depending on the required output voltage and / or charge / discharge capacity.

[0006] Meanwhile, cylindrical, prismatic, and pouch-shaped battery cells are known as types of unit secondary battery cells. Among these, pouch-shaped batteries incorporate a stacked electrode assembly in which anodes and cathodes are repeatedly laminated in the thickness direction along with a separator. Recently, a zigzag stacking method has been widely used as a method for manufacturing such stacked electrode assemblies, in which anodes and cathodes are alternately laminated between each layer of a separator that is continuously supplied and folded in a zigzag pattern.

[0007] Fig. 1 illustrates a manufacturing process of an electrode assembly through zigzag stacking, and Fig. 2 illustrates an electrode assembly manufactured through zigzag stacking. Referring to these drawings, the process of manufacturing an electrode assembly (EA) through zigzag stacking is performed by folding a continuously supplied separator (3) in a zigzag pattern and alternately stacking a positive electrode (1) and a negative electrode (2) between each layer. As a result, a plurality of folding portions (F) arranged in the thickness direction are formed on both horizontal ends of the electrode assembly (EA).

[0008] Since the folding portion (F) is not formed at the longitudinal end portions of the electrode assembly (EA), the electrode assembly (EA) has a shape in which the ends along the transverse direction are thicker and less compressible than the center portion, and thus the overall shape of the electrode assembly (EA) becomes a shape that is concave downward from the transverse center portion. A pouch-type battery is manufactured by inserting the electrode assembly (EA) into a pouch and then sealing the pouch. However, the difference in thickness between the central and end portions of the electrode assembly (EA) and the concave shape in the central portion make it difficult to insert the electrode assembly (EA) into the pouch. In addition, the uneven cross-section also lowers the energy density of the pouch-type battery, which is formed into an overall rectangular parallelepiped and is arranged in multiple pieces. On the other hand, the difference in thickness and compressibility of the electrode assembly (EA) along the transverse direction makes the entire electrode assembly (EA) vulnerable to bending load, torsional load, and buckling load.

[0009] The present invention was created under the background of the above-described prior art, and aims to provide a structure of an electrode assembly with improved pouch insertability.

[0010] The present invention also aims to provide a structure of an electrode assembly that can improve the energy density of a battery cell in an electrode assembly that is built into a pouch and constitutes a battery cell.

[0011] The present invention also aims to provide a structure of an electrode assembly having improved structural stability during placement and insertion and having high resistance to bending load, torsional load, and buckling load.

[0012] Specifically, the present invention aims to provide a shape of a separator that is continuously folded and laminated together with an electrode to form an electrode assembly, a folding method thereof, and a method for manufacturing an electrode assembly by laminating the separator together with an electrode.

[0013] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0014] In order to solve the above problem, the present invention provides a shape of a development diagram of a separator having a first side and a second side, and being repeatedly folded and laminated together with a first electrode and a second electrode to form an electrode assembly.

[0015] According to the present invention, in the above development diagram, first and second regions that are alternately repeated and connected in a chain are defined, and a first direction, a second direction intersecting the first direction, a third direction opposite the first direction, and a fourth direction opposite the second direction are defined.

[0016] At this time, each of the first regions is connected to the first direction side or the second direction side of one second region, and each of the second regions is connected to the third direction side or the fourth direction side of one first region.

[0017] According to one embodiment of the present invention, the separator may be folded such that the first surface of the first region and the second surface of the second region face a first thickness direction, and the second surface of the first region and the first surface of the second region face a second thickness direction, and the first region and the second region alternately and repeatedly overlap along the thickness direction. In this way, the separator in a folded state has folded portions formed evenly on all four sides. Accordingly, the electrode assembly including the separator may have a uniform thickness regardless of the direction and may have improved pouch insertability.

[0018] The first region and the second region may be substantially parallelograms that are congruent with each other. Accordingly, when the separator is folded, all of the first region and the second region may completely overlap in the thickness direction.

[0019] Specifically, according to one embodiment of the present invention, it is preferable that the first region and the second region are substantially congruent rectangles. At this time, the first direction and the third direction may be parallel to the vertical direction, and the second direction and the fourth direction may be parallel to the horizontal direction orthogonal to the vertical direction. Accordingly, the completed electrode assembly may have an overall rectangular shape in plan view, and the folding portion of the separator may be evenly formed on both horizontal end portions and both vertical end portions of the electrode assembly.

[0020] The above-described membrane unfolding pattern may have a shape extending in an inclined extension direction with respect to the first to fourth directions. Accordingly, the above-described membrane unfolding pattern can be obtained by cutting a predetermined region from a membrane sheet extending in the extension direction with a constant width. Generally, membrane sheets are manufactured in the form of a roll that is extended with a constant width and wound, so if the above-described membrane unfolding pattern can be easily manufactured from such a membrane sheet, there is a significant manufacturing advantage.

[0021] The present invention also provides a structure of an electrode assembly comprising a first electrode; a second electrode; and a separator having a first side and a second side, and being repeatedly folded and laminated together with the first electrode and the second electrode.

[0022] According to the present invention, in the development diagram of the separator, first and second regions that are alternately repeated and connected in a chain are defined, and in the development diagram of the separator, a first direction, a second direction intersecting the first direction, a third direction opposite the first direction, and a fourth direction opposite the second direction are defined.

[0023] At this time, each of the first regions is connected to the first direction side or the second direction side of one second region, and each of the second regions is connected to the third direction side or the fourth direction side of one first region.

[0024] Each of the first to fourth directions may be defined as a consistent direction in all regions in the developed view of the separator, and may be defined differently for each region when the separator is folded. For example, when a boundary between two regions adjacent to each other in the first direction and the third direction in the developed view is folded, the first direction and the third direction in the folded state may be defined as opposite directions between the two regions. That is, in this case, the first direction in one of the two regions may coincide with the third direction in the other region, and the third direction in one of the two regions may coincide with the first direction in the other region.

[0025] According to the present invention, the separator is folded so that the first surface of the first region and the second surface of the second region face the first thickness direction, and the second surface of the first region and the first surface of the second region face the second thickness direction, and the first region and the second region are alternately and repeatedly overlapped along the thickness direction.

[0026] The separator, in this folded state, has folded portions evenly formed on all four sides. Accordingly, the electrode assembly can have a uniform thickness regardless of direction and improved pouch insertability.

[0027] At this time, the first electrode is laminated on the first surface of the first region, and the second electrode is laminated on the second surface of the second region. Accordingly, all of the first electrodes and the second electrodes can be overlapped while being isolated from each other by the separator.

[0028] The first region and the second region may be substantially parallelograms that are congruent with each other. Accordingly, when the separator is folded, all of the first region and the second region may completely overlap in the thickness direction.

[0029] Specifically, according to one embodiment of the present invention, it is preferable that the first region and the second region are substantially congruent rectangles. At this time, the first direction and the third direction may be parallel to the vertical direction, and the second direction and the fourth direction may be parallel to the horizontal direction orthogonal to the vertical direction. Accordingly, the completed electrode assembly may have an overall rectangular shape in plan view, and the folding portion of the separator may be evenly formed on both horizontal end portions and both vertical end portions of the electrode assembly.

[0030] The above-described membrane unfolding pattern may have a shape extending in an inclined extension direction with respect to the first to fourth directions. Accordingly, the above-described membrane unfolding pattern can be obtained by cutting a predetermined region from a membrane sheet extending in the extension direction with a constant width. Generally, membrane sheets are manufactured in the form of a roll that is extended with a constant width and wound, so if the above-described membrane unfolding pattern can be easily manufactured from such a membrane sheet, there is a significant manufacturing advantage.

[0031] According to one embodiment of the present invention, the first electrode may have a first tab protruding in the second direction with respect to the adjacent first region, and the second electrode may have a second tab protruding in the fourth direction with respect to the adjacent second region. According to this embodiment, in the completed electrode assembly, both the first tab and the second tab may protrude to both sides of the electrode assembly in the horizontal direction.

[0032] At this time, it is preferable that the first tab and the second tab are positioned so as not to overlap each other in the thickness direction so that the first tab and the second tab do not cause a short circuit even without separate insulation.

[0033] For example, according to one embodiment of the present invention, the electrode assembly has a substantially rectangular plane with long sides and short sides defined, and the first tab and the second tab can be arranged in the long side direction relative to each other.

[0034] More specifically, the first tab may protrude from a position that is biased in the first direction or the third direction with respect to the center of the second direction side of the most adjacent first region, and the second tab may protrude from a position that is biased in the third direction or the first direction with respect to the center of the fourth direction side of the most adjacent second region.

[0035] Accordingly, in the completed electrode assembly, the first tab may protrude from a position that is tilted to one side in the vertical direction from one horizontal end of the electrode assembly and from a position that is tilted to the other side in the vertical direction from the other horizontal end, and the second tab may protrude from a position that is tilted to the other side in the vertical direction from one horizontal end of the electrode assembly and from a position that is tilted to one side in the vertical direction from the other horizontal end. Thereafter, by appropriately connecting the first tab and the second tab to each other, the first electrode and the second electrode may be connected to each other in parallel and / or in series.

[0036] According to one variation, the first electrode may have a first tab protruding in the first direction with respect to the adjacent first region, and the second electrode may have a second tab protruding in the third direction with respect to the adjacent second region. In this case, the electrode assembly may have a substantially rectangular plane with defined horizontal and vertical directions.

[0037] According to this modified example, in the completed electrode assembly, the first tab may protrude on both horizontal sides of the electrode assembly, and the second tab may protrude on both vertical sides of the electrode assembly. Thereafter, by appropriately connecting the first tab and the second tab to each other, the first electrode and the second electrode may be connected in parallel and / or in series with each other.

[0038] The present invention can provide a structure of an electrode assembly having a flatter shape and improved pouch insertability by forming folding parts evenly in four directions.

[0039] The present invention also provides a structure of an electrode assembly capable of improving the energy density of a battery cell by having a shape that minimizes empty space when embedded in a pouch having a substantially rectangular parallelepiped shape.

[0040] The present invention also provides a structure of an electrode assembly having a symmetrical and flat shape and structure, thereby improving structural stability during placement and pouch insertion, and having high resistance to bending load, torsional load, and buckling load.

[0041] Specifically, the present invention can provide a shape of a separator that is folded continuously in four different directions and laminated together with an electrode to form an electrode assembly, a folding method thereof, and a method of manufacturing an electrode assembly by laminating the separator together with an electrode, and can provide a structure of an electrode assembly manufactured thereby.

[0042] In addition, the present invention may have various other effects, which will be described in each embodiment, or the description of effects that can be easily inferred by a person skilled in the art will be omitted.

[0043] Figure 1 shows a manufacturing process of an electrode assembly through zigzag stacking.

[0044] Figure 2 shows an electrode assembly manufactured through zigzag stacking.

[0045] Figure 3 shows an expanded view of a separation membrane according to one embodiment of the present invention.

[0046] Figure 4 shows the process of cutting the membrane sheet to produce the development diagram of Figure 3.

[0047] Figures 5 to 9 illustrate a process of manufacturing an electrode assembly by stacking electrodes and folding a separator in one embodiment of the present invention.

[0048] FIG. 10 shows only the separator, omitting the electrodes, in an electrode assembly in a state where folding is completed according to one embodiment of the present invention.

[0049] FIG. 11 is a layout diagram showing the stacking positions of electrodes according to one embodiment of the present invention on the development diagram of FIG. 3.

[0050] Fig. 12 shows the formation position of a tab according to one embodiment of the present invention on the layout diagram of Fig. 11.

[0051] Figure 13 shows a completed electrode assembly according to one embodiment of the present invention.

[0052] Fig. 14 shows the formation position of a tab according to a modified example of the present invention on the layout diagram of Fig. 11.

[0053] Figure 15 shows a completed electrode assembly according to one variation of the present invention.

[0054] [Explanation of symbols]

[0055] 1: First electrode (anode) 10: First tab 2: Second electrode (cathode) 20: Second tab 3: Separator 3a: First side 3b: Second side 30: Separator sheet 31: First area 32: Second area EA: Electrode assembly F: Folding section UF: Developed view D1~4: First~fourth directions D0: Extension direction

[0056] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0057] Although the terms "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0058] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0059] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0060] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0061] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0062] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C through D", this means C or more and D or less, unless otherwise stated.

[0063] Hereinafter, a preferred embodiment of the present invention will be described with reference to the attached drawings.

[0064] An electrode assembly (EA) according to one embodiment of the present invention is configured by alternately and repeatedly stacking a first electrode (1) and a second electrode (2) between each layer of a separator (3) that is continuously folded to form multiple layers overlapping in the thickness direction.

[0065] At this time, the first electrode (1) and the second electrode (2) may be one or the other of the positive and negative electrodes, respectively.

[0066] At this time, the separator (3) may be a single unfolded form (UF) including a plurality of regions divided by a single border and a plurality of folding lines, folded along the folding lines. At this time, one separator (3) may be included per electrode assembly (EA), but in some cases, a plurality of separators (3) folded from each of the unfolded forms (UF) may constitute one electrode assembly (EA).

[0067] Hereinafter, the shape of the development diagram (UF) of the separator (3) will first be described in detail, and then the structure of the electrode assembly (EA) manufactured by folding the separator (3) having the development diagram (UF) as described above and stacking it together with the first electrode (1) and the second electrode (2) will be described in detail.

[0068] Figure 3 illustrates an unfolded view of a separator according to one embodiment of the present invention. Referring to this, the separator (3) has a first surface (3a) and a second surface (3b) that face each other in the thickness direction. Each of the first surface (3a) and the second surface (3b) is defined as a single continuous surface not only when the separator (3) is unfolded but also when it is folded.

[0069] According to the present invention, in the development diagram (UF), a first direction (D1), a second direction (D2) intersecting the first direction (D1), a third direction (D3) opposite the first direction (D1), and a fourth direction (D4) opposite the second direction (D2) are defined.

[0070] At this time, in the above development diagram (UF), a first region (31) and a second region (32) that are alternately repeated and connected in a chain are defined. In other words, the separation membrane (3) includes at least one different first region (31) and second region (32) within its entire area. That the first region (31) and the second region (32) are alternately repeated and connected in a chain may mean that the first region (31) and the second region (32) are alternately connected along a predetermined (zigzag, according to the present embodiment) path to form a chain.

[0071] According to one embodiment of the present invention, each of the first regions (31) is connected to the first direction (D1) side or the second direction (D2) side of one second region (32), and each of the second regions (32) is connected to the third direction (D3) side or the fourth direction (D4) side of one first region (31).

[0072] More specifically, the first region (31) and the second region (32) can be arranged in the following four cases:

[0073] 1. When the first region (31) constitutes the starting point of the chain and the second region (32) constitutes the ending point of the chain:

[0074] In this case, each of the first regions (31) is connected to the first direction (D1) side of one second region (32), and each of the second regions (32) is connected to the third direction (D3) side of one first region (31). At this time, each of the first regions (31) except for the first region (31) constituting the starting end of the chain is simultaneously connected to the second direction (D2) side of one second region (32), and each of the second regions (32) except for the second region (32) constituting the ending end of the chain is simultaneously connected to the fourth direction (D4) side of one first region (31).

[0075] 2. When the second region (32) constitutes the starting end of the chain and the first region (31) constitutes the ending end of the chain (in the present embodiment):

[0076] In this case, each of the first regions (31) is connected to the second direction (D2) side of one second region (32), and each of the second regions (32) is connected to the fourth direction (D4) side of one first region (31). At this time, each of the first regions (31) except for the first region (31) constituting the end of the chain is simultaneously connected to the first direction (D1) side of one second region (32), and each of the second regions (32) except for the second region (32) constituting the start of the chain is simultaneously connected to the third direction (D3) side of one first region (31).

[0077] 3. When the above first region (31) constitutes the starting and ending ends of the chain:

[0078] In this case, each of the second regions (32) is connected to the third direction (D3) side of one first region (31) and at the same time connected to the fourth direction (D4) side of another first region (31). At this time, the first region (31) constituting the starting end of the chain is connected to the first direction (D1) side of one second region (32), and the first region (31) constituting the ending end of the chain is connected to the second direction (D2) side of another second region (32). Each of the first regions (31) excluding these is connected to the first direction (D1) side of one second region (32) and at the same time connected to the second direction (D2) side of another second region (32).

[0079] 4. When the above second region (32) constitutes the starting and ending ends of the chain:

[0080] In this case, each of the first regions (31) is connected to the first direction (D1) side of one second region (32) and at the same time connected to the second direction (D2) side of another second region (32). At this time, the second region (32) constituting the starting end of the chain is connected to the fourth direction (D4) side of one first region (31), and the second region (32) constituting the ending end of the chain is connected to the third direction (D3) side of the other first region (31). Each of the second regions (32) excluding these is connected to the third direction (D3) side of one first region (31) and at the same time connected to the fourth direction (D4) side of the other first region (31).

[0081] Each of the first to fourth directions (D1, D2, D3, D4) is defined as a consistent direction in all regions (31, 32) on the development view (UF) of the separator (3), and may be defined differently for each region (31, 32) when the separator (3) is folded. For example, when the boundary between any two regions adjacent to each other in the first direction (D1) and the third direction (D3) on the development view (UF) is folded, the first direction (D1) and the third direction (D3) in the folded state may be defined as opposite directions between the two regions. That is, in this case, the first direction (D1) in one of the two regions may coincide with the third direction (D3) in the other region, and the third direction (D3) in one of the two regions may coincide with the first direction (D1) in the other region.

[0082] The first region (31) and the second region (32) may be substantially parallelograms that are congruent with each other. Accordingly, when the separator (3) is folded, all of the first region (31) and the second region (32) may completely overlap in the thickness direction.

[0083] Specifically, according to one embodiment of the present invention, it is preferable that the first region (31) and the second region (32) are substantially congruent rectangles. At this time, the first direction (D1) and the third direction (D3) may be parallel to the vertical direction, and the second direction (D2) and the fourth direction (D4) may be parallel to the horizontal direction perpendicular to the vertical direction. Accordingly, the completed electrode assembly (EA) may have an overall rectangular shape in plan view, and the folding portions of the separator (3) may be evenly formed on both horizontal end portions and both vertical end portions of the electrode assembly (EA).

[0084] FIG. 4 illustrates a process for producing the developed view of FIG. 3 by cutting a membrane sheet. Referring to this, the membrane developed view (UF) may have a shape extending in an inclined extension direction (D0) with respect to the first to fourth directions (D1, D2, D3, D4). Accordingly, the membrane developed view (UF) may be obtained by cutting a predetermined area from the membrane sheet (30) extending with a constant width in the extension direction (D0). Generally, the membrane sheet (30) is manufactured in a roll shape that is extended with a constant width and wound, so there is a great advantage in manufacturing if the membrane developed view (UF) can be easily manufactured from such a membrane sheet (30).

[0085] Figures 5 to 9 illustrate a process of manufacturing an electrode assembly by stacking electrodes and folding a separator in one embodiment of the present invention. Referring to these drawings, the separator (3) is folded such that the first surface (3a) of the first region (31) and the second surface (3b) of the second region (32) face the first thickness direction, and the second surface (3b) of the first region (31) and the first surface (3a) of the second region (32) face the second thickness direction, while the first region (31) and the second region (32) are alternately and repeatedly overlapped along the thickness direction.

[0086] More specifically, the manufacturing process of the electrode assembly according to the present embodiment can be performed by sequentially repeating the different folding processes of the first to fourth steps, which correspond sequentially to each of the above FIGS. 5 to 8 . In the manufacturing process, the first to fourth steps need only be repeated sequentially, and any step can be the first step or the last step.

[0087] Step 1 (Figs. 5 and 9): After laminating the second electrode (2) on the second surface (3b) of the second region (32) located at one end of the unfolded view (UF) of the separator (3), the boundary between the second region (32) on which the second electrode (2) is laminated and the remaining portion of the separator (3) is folded. At this time, a folding portion is formed on the side of the second direction (D2) of the second region (32) on which the second electrode (2) is laminated. By performing this step, the separator (3) becomes in a state as shown in Fig. 6.

[0088] Step 2 (Fig. 6): After laminating the first electrode (1) on the first surface (3a) of the first region (31) located at one end of the unfolded view (UF) of the separator (3), the boundary between the first region (31) on which the first electrode (1) is laminated and the remaining portion of the separator (3) is folded. At this time, a folding portion is formed on the side of the third direction (D3) of the first region (31) on which the first electrode (1) is laminated. By performing this step, the separator (3) becomes in a state as shown in Fig. 7.

[0089] Step 3 (Fig. 7): After laminating the second electrode (2) on the second surface (3b) of the second region (32) located at one end of the unfolded view (UF) of the separator (3), the boundary between the second region (32) on which the second electrode (2) is laminated and the remaining portion of the separator (3) is folded. At this time, a folding portion is formed on the side of the second direction (D2) of the second region (32) on which the second electrode (2) is laminated. By performing this step, the separator (3) becomes in a state as shown in Fig. 8.

[0090] Step 4 (Fig. 8): After laminating the first electrode (1) on the first surface (3a) of the first region (31) located at one end of the unfolded view (UF) of the separator (3), the boundary between the first region (31) on which the first electrode (1) is laminated and the remaining portion of the separator (3) is folded. At this time, a folding portion is formed on the side of the third direction (D3) of the first region (31) on which the first electrode (1) is laminated. By performing this step, the separator (3) becomes in a state as shown in Fig. 9.

[0091] Fig. 10 illustrates only the separator, omitting the electrodes, in a folded electrode assembly according to one embodiment of the present invention. Referring to this, the separator (3) in the folded state as described above has folded portions evenly formed on all four sides. Accordingly, the electrode assembly (EA) can have a uniform thickness regardless of direction and improved pouch insertability.

[0092] Fig. 11 is a layout diagram showing the stacking positions of electrodes according to one embodiment of the present invention on the development diagram of Fig. 3. In other words, Fig. 11 shows a state in which the electrode assembly (EA) manufactured by sequentially repeating the steps of Figs. 5 to 9 is again developed in a state in which the first electrode (1) and the second electrode (2) are stacked. Referring to this, it can be seen that the first electrode (1) is stacked on the first surface (3a) of the first region (31), and the second electrode (2) is stacked on the second surface (3b) of the second region (32). At this time, since each of the first region (31) and the second region (32) is not connected to a similar region, all of the first electrodes (1) and the second electrodes (2) can overlap while being isolated from each other by the separator (3).

[0093] At this time, when the first region (31) and the second region (32) are substantially parallelograms that are congruent with each other, when the separator (3) is in a state where folding is complete, all of the first region (31) and the second region (32) can completely overlap in the thickness direction.

[0094] According to one embodiment of the present invention, it is preferable that the first region (31) and the second region (32) are substantially congruent rectangles. At this time, since the first direction (D1) and the third direction (D3) are parallel to the vertical direction, and the second direction (D2) and the fourth direction (D4) are parallel to the horizontal direction perpendicular to the vertical direction, the completed electrode assembly (EA) can be rectangular in plan view as a whole, and the folding portion of the separator (3) can be evenly formed on both horizontal end portions and both vertical end portions of the electrode assembly (EA).

[0095] The electrode assembly (EA) according to one embodiment of the present invention has a tab for electrically connecting the first electrode (1) and the second electrode (2) to an external terminal.

[0096] FIG. 12 illustrates a formation position of a tab according to an embodiment of the present invention on the layout diagram of FIG. 11, and FIG. 13 illustrates a completed electrode assembly according to an embodiment of the present invention. Referring to these drawings, the first electrode (1) may have a first tab (10) protruding toward the second direction (D2) with respect to the adjacent first region (31), and the second electrode (2) may have a second tab (20) protruding toward the fourth direction (D4) with respect to the adjacent second region (32). According to the present embodiment, in the completed electrode assembly (EA), both the first tab (10) and the second tab (20) may protrude to both sides of the horizontal direction of the electrode assembly (EA).

[0097] At this time, it is preferable that the first tab (10) and the second tab (20) are positioned so that they do not overlap each other in the thickness direction so that the first tab (10) and the second tab (20) do not cause a short circuit even without separate insulation.

[0098] For example, according to one embodiment of the present invention, the electrode assembly (EA) has a substantially rectangular plane with long sides and short sides defined, and the first tab (10) and the second tab (20) can be arranged in the long side direction relative to each other.

[0099] More specifically, the first tab (10) may protrude from a position that is tilted in the first direction (D1) or the third direction (D3) with respect to the center of the side of the second direction (D2) of the most adjacent first region (31), and the second tab (20) may protrude from a position that is tilted in the third direction (D3) or the first direction (D1) with respect to the center of the side of the fourth direction (D4) of the most adjacent second region (32).

[0100] Accordingly, in the completed electrode assembly (EA), the first tab (10) may protrude from a position that is tilted to one side in the vertical direction from one horizontal end of the electrode assembly (EA) and from a position that is tilted to the other side in the vertical direction from the other horizontal end, and the second tab (20) may protrude from a position that is tilted to the other side in the vertical direction from one horizontal end of the electrode assembly (EA) and from a position that is tilted to one side in the vertical direction from the other horizontal end. Thereafter, by appropriately connecting the first tab (10) and the second tab (20) to each other, the first electrode (1) and the second electrode (2) may be connected in parallel and / or in series with each other.

[0101] Fig. 14 illustrates the formation position of a tab according to a variation of the present invention in the layout diagram of Fig. 11, and Fig. 15 illustrates a completed electrode assembly according to a variation of the present invention. Referring to these drawings, the first electrode (1) may have a first tab (10) protruding in the first direction (D1) with respect to the adjacent first region (31), and the second electrode (2) may have a second tab (20) protruding in the third direction (D3) with respect to the adjacent second region (32). At this time, the electrode assembly (EA) may have a substantially rectangular plane in which the horizontal and vertical directions are defined.

[0102] According to this modified example, in the completed electrode assembly (EA), the first tab (10) may protrude to both horizontal sides of the electrode assembly (EA), and the second tab (20) may protrude to both vertical sides of the electrode assembly (EA). Thereafter, by appropriately connecting the first tab (10) and the second tab (20) to each other, the first electrode (1) and the second electrode (2) may be connected to each other in parallel and / or in series.

[0103] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0104] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. A development diagram of a separator having a first side and a second side, repeatedly folded, and laminated together with a first electrode and a second electrode to form an electrode assembly. The first and second areas are defined as being alternately repeated and connected in a chain, A first direction, a second direction intersecting the first direction, a third direction opposite the first direction, and a fourth direction opposite the second direction are defined, Each of the above first regions is connected to the first direction side or the second direction side of a second region, A membrane development diagram in which each of the second regions is connected to the third direction side or the fourth direction side of the first region.

2. In claim 1, the first direction and the third direction are parallel to the vertical direction, The above second direction and the above fourth direction are parallel to the horizontal direction perpendicular to the vertical direction, and are a membrane development diagram.

3. A membrane development diagram according to claim 1, wherein the first region and the second region are substantially parallelograms that are congruent to each other.

4. In claim 2, the first region and the second region are substantially congruent rectangles, a separation membrane development diagram.

5. In claim 1, a separation membrane development diagram having a shape extending in an extension direction inclined with respect to the first to fourth directions as a whole.

6. First electrode; second electrode; and A separator having a first side and a second side, and being repeatedly folded and laminated together with the first electrode and the second electrode; In the development diagram of the above separation membrane, the first region and the second region, which are alternately repeated and connected in a chain, are defined, In the development diagram of the above separation membrane, a first direction, a second direction intersecting the first direction, a third direction opposite the first direction, and a fourth direction opposite the second direction are defined, Each of the above first regions is connected to the first direction side or the second direction side of a second region, Each of the above second regions is connected to the third direction side or the fourth direction side of the first region, The above separator is folded so that the first surface of the first region and the second surface of the second region face the first thickness direction, and the second surface of the first region and the first surface of the second region face the second thickness direction, and the first region and the second region are alternately and repeatedly overlapped along the thickness direction. The above first electrode is laminated on the first surface of the above first region, An electrode assembly in which the second electrode is laminated on the second surface of the second region.

7. In claim 6, the first direction and the third direction are parallel to the vertical direction, An electrode assembly wherein the second direction and the fourth direction are parallel to the horizontal direction which is perpendicular to the vertical direction.

8. An electrode assembly according to claim 6, wherein the first region and the second region are substantially parallelograms that are congruent to each other.

9. An electrode assembly according to claim 8, wherein the first region and the second region are substantially congruent rectangular shapes.

10. In claim 6, the electrode assembly has a shape in which the separation membrane is extended in an inclined extension direction with respect to the first to fourth directions.

11. In claim 6, the first electrode has a first tab protruding toward the second direction with respect to the adjacent first region, An electrode assembly, wherein the second electrode has a second tab protruding toward the fourth direction with respect to the adjacent second region.

12. An electrode assembly according to claim 11, wherein the first tab and the second tab are arranged so as not to overlap each other in the thickness direction.

13. In claim 12, the electrode assembly has a substantially rectangular plane with defined long and short sides, An electrode assembly wherein the first tab and the second tab are arranged in a longitudinal direction relative to each other.

14. In claim 6, the first electrode has a first tab protruding in the first direction with respect to the adjacent first region, An electrode assembly, wherein the second electrode has a second tab protruding in the third direction with respect to the adjacent second region.

15. In claim 14, the electrode assembly has a substantially rectangular plane with defined horizontal and vertical directions, The above first tab protrudes on both sides in the horizontal direction, The above second tab is an electrode assembly that protrudes on both sides in the vertical direction.

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