Bipolar cell and method for manufacturing bipolar cell

Abstract

A method for manufacturing a bipolar cell according to embodiments of the present invention may comprise: a preparation step for preparing an electrode assembly including a plurality of bipolar electrodes and a separator; a first electrode plate coupling step for coupling a frame including an insulating material to a first electrode plate; an alignment step for disposing the electrode assembly on the upper surface of the first electrode plate; and a second electrode plate coupling step for coupling a second electrode plate to the frame so as to cover the upper surface of the electrode assembly.

Description

Bipolar cell and method for manufacturing a bipolar cell

[0001] The present invention relates to a bipolar cell and a method for manufacturing a bipolar cell.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 2025-0002328 dated January 7, 2025, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003] Secondary batteries are rechargeable and dischargeable, so they are widely used in mobile devices such as digital cameras, mobile phones, and laptops, and recently, they are receiving attention as an energy source for electric vehicles and energy storage systems (ESS).

[0004] As large capacity and high output power are required in electric vehicles and energy storage systems, there is a need for a new secondary battery structure capable of stably providing high-voltage power and a manufacturing method capable of producing such a new secondary battery.

[0005] The present invention is devised to solve at least some of the problems of the prior art as described above, and provides a method for manufacturing a bipolar cell in which multiple unit electrodes are stacked to be connected in series, and a bipolar cell manufactured thereby.

[0006] To achieve the above objective, embodiments of the present invention provide a method for manufacturing a bipolar cell, comprising: a preparation step of preparing an electrode assembly including a plurality of bipolar electrodes and a separator; a first electrode plate coupling step of coupling a frame including an insulating material to a first electrode plate; an alignment step of placing the electrode assembly on the upper surface of the first electrode plate; and a second electrode plate coupling step in which the second electrode plate is coupled to the frame so as to cover the upper surface of the electrode assembly.

[0007] In the embodiments, the preparation step may include a stacking step of alternately stacking a plurality of bipolar electrodes and a separator to form an electrode stack, and a sealing step in which a sealing portion is formed to seal the electrode stack along the perimeter of the electrode stack.

[0008] In the embodiments, in the first electrode plate coupling step, a first subframe having an opening formed on at least one side is coupled with the first electrode plate, and in the alignment step, the electrode assembly can be slidably inserted along the upper surface of the first electrode plate through the opening.

[0009] In the embodiments, after the alignment step, the second subframe can be joined to the first subframe to close the opening.

[0010] In the embodiments, an activation step that is performed after the second electrode plate coupling step and activates the electrode assembly may be further included.

[0011] In the embodiments, a first sealing member may be interposed between one side of the frame and the first electrode plate or between the other side of the frame and the second electrode plate.

[0012] In the embodiments, the first electrode plate coupling step is performed after the alignment step, and in the first electrode plate coupling step, the frame may be positioned along the four sides of the electrode assembly.

[0013] In the embodiments, the frame may have an integrated picture frame structure.

[0014] In the embodiments, the preparation step may include an activation step that activates the electrode assembly.

[0015] In the embodiments, the bipolar cell manufacturing method may further include a first folding step of folding at least one edge of the first electrode plate to be attached to the side of the frame.

[0016] In the embodiments, the bipolar cell manufacturing method further includes a second bending step of bending one edge of the second electrode plate to be attached to the side of the frame, and the first bending portion, which is the bent portion of the first electrode plate, and the second bending portion, which is the bent portion of the second electrode plate, may be spaced apart from each other in the stacking direction of the electrode assembly.

[0017] In the embodiments, the first bend and the second bend may be spaced apart from each other with the protrusion of the frame in between.

[0018] In the embodiments, a second sealing member is disposed on the side of the frame, and the first bend and the second bend can be fused to the frame through the second sealing member.

[0019] In the embodiments, the frame includes a first frame coupled to a first edge of a first electrode plate, and a second frame coupled to a second edge extending in a direction different from the first edge of the first electrode plate, and the first frame and the second frame may be ultrasonically fused or thermally fused to each other.

[0020] In embodiments, a bipolar cell is provided, comprising: an electrode assembly including a plurality of bipolar electrodes and a separator; a first electrode plate disposed facing one side of the electrode assembly; a second electrode plate disposed facing the opposite side of one side of the electrode assembly; and a frame disposed along the edge of the electrode assembly between the first electrode plate and the second electrode plate.

[0021] According to the embodiments, a method for manufacturing a bipolar cell in which multiple unit electrodes are stacked to be connected in series and a bipolar cell manufactured thereby can be provided.

[0022] According to the bipolar cell manufacturing method of the embodiments, a bipolar cell capable of outputting high voltage power while having high structural, electrical, and thermal stability can be manufactured.

[0023] FIG. 1 is a perspective view of a bipolar cell according to one embodiment.

[0024] FIG. 2 is an exploded perspective view of a bipolar cell according to one embodiment.

[0025] Figure 3 is an exemplary cross-sectional view of a bipolar cell along line II' of Figure 1.

[0026] FIG. 4 is a cross-sectional view of a frame of a bipolar cell according to one embodiment.

[0027] FIG. 5 is a reference diagram exemplarily illustrating a method for manufacturing a bipolar cell according to one embodiment.

[0028] FIG. 6 is a reference diagram exemplarily showing how an electrode assembly is inserted into a frame in a method for manufacturing a bipolar cell according to one embodiment.

[0029] FIG. 7 is a reference diagram exemplarily showing the bending of the edge of an electrode plate in a method for manufacturing a bipolar cell according to one embodiment.

[0030] FIG. 8 is a reference diagram exemplifying a method for manufacturing a bipolar cell according to another embodiment.

[0031] Prior to the detailed description of the present invention, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, they should be interpreted in a sense and concept consistent with the technical spirit of the present invention, based on the principle that the inventor may appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all aspects of the technical spirit of the present invention. Therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0032] Identical reference numbers or symbols in each drawing attached to this specification represent parts or components that perform substantially the same function. For convenience of explanation and understanding, the same reference numbers or symbols may be used to describe different embodiments. That is, even if components having the same reference number are depicted in multiple drawings, the multiple drawings do not all represent a single embodiment.

[0033] In the following description, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprising" or "constituting" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0034] In addition, it should be noted in advance that expressions such as upper side, top, lower side, bottom, side, front, and rear in the following description are based on the direction depicted in the drawings, and may be expressed differently if the direction of the object changes.

[0035] Additionally, in this specification and claims, terms including ordinal numbers, such as "first," "second," etc., may be used to distinguish between components. These ordinal numbers are used to distinguish identical or similar components from one another, and the meaning of the terms should not be limited by the use of such ordinal numbers. For example, the order of use or arrangement of components combined with such ordinal numbers should not be limited by the number. If necessary, each ordinal number may be used interchangeably.

[0036] Embodiments of the present invention will be described below with reference to the attached drawings. However, the scope of the present invention is not limited to the embodiments presented. For example, a person skilled in the art who understands the scope of the present invention may propose other embodiments that fall within the scope of the concept of the present invention by adding, changing, or deleting components, and such embodiments shall also be deemed to be within the scope of the concept of the present invention. In the drawings, the shapes and sizes of elements may be exaggerated for clearer explanation.

[0037] FIG. 1 is a perspective view of a bipolar cell (10) according to one embodiment.

[0038] FIG. 2 is an exploded perspective view of a bipolar cell (10) according to one embodiment.

[0039] FIG. 3 is an exemplary cross-sectional view of a bipolar cell (10) along the line II' of FIG. 1.

[0040] FIG. 4 is a cross-sectional view of the frame of a bipolar cell (10) according to one embodiment.

[0041] A bipolar cell (10) according to one embodiment may include an electrode assembly (100) comprising a plurality of bipolar electrodes (BE), an electrode plate (200, 300) electrically connected to the electrode assembly (100), and a frame (600) coupled to the electrode plate (200, 300).

[0042] An electrode assembly (100) of a bipolar cell (10) according to one embodiment may include an electrode stack (ES) in which a plurality of bipolar electrodes (BE) and a separator (140) are alternately stacked along one direction, and a sealing portion (150) that seals the electrode stack (ES).

[0043] A bipolar electrode (BE) may have a structure in which electrode layers (120, 130) having different polarities are formed on each side of a current collector (110). For example, referring to FIGS. 2 and FIGS. 3 together, in any bipolar electrode (BE), a first electrode layer (120) may be disposed on one side of the current collector (110), and a second electrode layer (130) having an electrical polarity opposite to that of the first electrode layer (120) may be disposed on the other side of the current collector (110). For example, the first electrode layer (120) may be a negative electrode layer, and the second electrode layer (130) may be a positive electrode layer. Alternatively, the first electrode layer (120) may be a positive electrode layer, and the second electrode layer (130) may be a negative electrode layer. In each bipolar electrode (BE), electrons emitted from the negative electrode layer may be moved to the positive electrode layer through the current collector (110).

[0044] In one embodiment, the current collector (110) may have a flat structure made of a conductive material (e.g., a conductive metal such as copper or aluminum) so as to function as a current pathway in the bipolar electrode (BE). If necessary, the current collector (110) may be formed to include a porous structure or a mesh structure.

[0045] In one embodiment, the cathode layer may be formed using materials such as graphite, silicon (Si), or lithium (Li), but is not limited thereto. Additionally, the anode layer may be formed using materials such as lithium metal oxide, such as lithium cobalt oxide (LiCoO2), lithium nickel manganese cobalt oxide (NMC), or lithium iron phosphate (LFP).

[0046] The electrode stack (ES) can be formed by stacking a plurality of bipolar electrodes (BE), each having electrode layers (120, 130) formed on both sides of a current collector (110), in one direction (e.g., the Z-axis direction of FIG. 3) with a separator (140) in between. In the following description, unless otherwise stated, the ‘stacking direction’ may refer to the stacking direction of the plurality of bipolar electrodes (BE). Additionally, the stacking direction may be described as the ‘first direction’.

[0047] In one embodiment, an electrode layer (120, 130) may be formed on only one side of a current collector (110) positioned at the top or bottom of an electrode stack (ES). For example, referring to FIG. 3, in the current collector (110) positioned at the bottom among a plurality of current collectors (110) included in the electrode stack (ES), a first electrode layer (120) may be formed on the side facing the separator (140), but the electrode layer (130) may not be formed on the opposite side. Alternatively, referring to FIG. 3, in the current collector (110) positioned at the top among a plurality of current collectors (110) included in the electrode stack (ES), a second electrode layer (130) may be formed on the side facing the separator (140), but the first electrode layer (120) may not be formed on the opposite side.

[0048] A separator (140) is placed between multiple bipolar electrodes (BE) to prevent the bipolar electrodes (BE) from coming into contact with each other and short-circuiting.

[0049] For example, the separator (140) may be a porous film placed between a plurality of bipolar electrodes (BE). The separator (140) may be impregnated with a liquid electrolyte to enable the movement of ions between the anode layer and the cathode layer. Alternatively, the separator (140) may be formed in the form of a gel having fluidity or may be formed as a solid. When the separator (140) is provided in the form of a gel or a solid, the possibility of leakage is reduced and structural stability is improved compared to when a separator structure impregnated with a liquid electrolyte is applied. However, the shape of the separator (140) is not limited to that described above, and the separator (140) may be formed in any shape that enables the movement of ions while preventing the anode layer and the cathode layer of two adjacent stacked bipolar electrodes (BE) from coming into contact with each other.

[0050] In one embodiment, a stacked structure of a plurality of bipolar electrodes (BE) and a separator (140) can form an electrical series structure in an electrode stack (ES). For example, referring to FIG. 3, a plurality of bipolar electrodes (BE) can be stacked along a first direction (e.g., Z-axis direction) with a separator (140) in between, with the first electrode layer (120) facing in the same direction, to form an electrical series structure. In this way, by forming a stacked structure in which a plurality of bipolar electrodes (BE) are connected in series with each other, the bipolar cell (10) can supply high voltage and high density electrical energy to the outside.

[0051] The sealing portion (150) can surround and seal the electrode stack (ES). For example, the sealing portion (150) is formed along the perimeter of the electrode stack (ES) to primarily seal the electrode stack (ES) from the outside and protect the electrode stack (ES) from external moisture or foreign matter.

[0052] The sealing portion (150) can prevent the electrolyte from leaking out of the electrode assembly (100). Alternatively, as described above, the separator (140) may be provided in the form of a gel having a certain fluidity, and in this case, the separator (140) may not leak out of the electrode assembly (100) due to the sealing structure of the sealing portion (150).

[0053] The sealing portion (150) can fix and support the electrode stack (ES). The sealing portion (150) is formed to have a predetermined thickness in a direction perpendicular to the first direction (Z-axis direction), which is the stacking direction (e.g., X-axis direction), and at least a portion of the current collector (110) or the separator (140) can be inserted into and fixed to the sealing portion (150). Each bipolar electrode (BE) of the electrode stack (ES) can be prevented from being displaced or misaligned from its original position due to the support structure of the sealing portion (150).

[0054] In one embodiment, the electrode stack (ES) may be arranged so that current collectors (110) are exposed at both ends of the stacking direction. The uppermost current collector (110) and the lowermost current collector (110) of the electrode stack (ES) in the stacking direction may form an electrical connection with the electrode plates (200, 300). The uppermost current collector (110) and the lowermost current collector (110) in the stacking direction may each have opposite electrical polarities due to the contacting negative and positive layers.

[0055] In one embodiment, the bipolar cell (10) may include a plurality of electrode plates (200, 300) that cover one side and the other side of the electrode assembly (100), respectively, and are electrically connected to the electrode assembly (100). For example, referring to FIG. 2 and FIG. 3 together, the plurality of electrode plates (200, 300) may include a first electrode plate (200) that covers the lower surface of the electrode assembly (100) and a second electrode plate (300) that covers the upper surface of the electrode assembly (100).

[0056] The electrode plates (200, 300) may be formed of a conductive material, such as metal, at least a portion thereof, and may be electrically connected to the electrode assembly (100) to serve as terminals for connecting the electrode assembly (100) to an electrical circuit outside the bipolar cell (10). For example, in the bipolar cell (10), one of the electrode plates (200, 300) may be a negative terminal and the other may be a positive terminal.

[0057] One bipolar cell (10) can be electrically connected to an external electrical circuit or another bipolar cell (10) through an electrode plate (200, 300). As such, a large-area electrode plate (200, 300) covering the upper or lower surface of the electrode assembly (100) is utilized as a terminal, thereby enabling the realization of a unit cell in which the electrical resistance in the terminal area is very low and the thermal energy generated by the resistance is also very low.

[0058] A bipolar cell (10) according to one embodiment of the present invention may further include a connecting member (400) that electrically connects an electrode plate (200, 300) and a bipolar electrode (BE). For example, referring to FIG. 3, a connecting member (400) electrically connected to a current collector (110) may be disposed on the outermost sides of one side and the other side of an electrode assembly (100). One side of the connecting member (400) may be electrically connected to the current collector (110) by contacting it, and the other side of the connecting member (400) may be electrically connected to the electrode plate (200, 300) by contacting it.

[0059] The connecting member (400) may be provided with a conductive foam having a certain compressibility in the stacking direction, but is not limited thereto. In addition, the shape or placement position of the connecting member (400) is not limited to that shown in FIG. 3, and may have any shape as long as it can electrically connect the electrode assembly (100) and the electrode plates (200, 300).

[0060] In various embodiments, the electrode assembly (100) may have a current collector (110) that is in direct contact with the electrode plate (200, 300) or electrically connected through a separate means, in which case the connecting member (400) may be omitted.

[0061] In one embodiment, if necessary, a binder may be used between the electrode assembly (100) and the electrode plate (200, 300) to fix the mutual position between the electrode assembly (100) and the electrode plate (200, 300). For example, the binder may be a conductive binder. However, alternatively, the electrode assembly (100) may be electrically connected to the electrode plate (200, 300) in a state of close contact on the electrode plate (200, 300) without a separate bonding member or adhesive member such as a binder.

[0062] Referring to FIG. 2 and FIG. 4 together, the first electrode plate (200) and the second electrode plate (300) may be spaced apart in a first direction (Z-axis direction) with a frame (600) positioned along at least one side of the electrode assembly (100).

[0063] In one embodiment, the frame (600) may be positioned in the spaced-out space between the edge of the first electrode plate (200) and the edge of the second electrode plate (300) to form the side of the bipolar battery. For example, referring to FIG. 2, the frame (600) may be positioned along the perimeter of the electrode assembly (100) to protect the side of the electrode assembly (100) and to support the first electrode plate (200) and the second electrode plate (300) so as to maintain a gap between them.

[0064] In one embodiment, the frame (600) may be formed by combining a first frame (610) and a second frame (620). For example, referring to FIG. 2, the entire frame (600) of the bipolar cell (10) may be formed by combining a first frame (610) and a second frame (620) that face different sides of the electrode assembly (100). For example, the first frame (610) may be provided as a pair and positioned to face the electrode assembly (100) in a second direction (X-axis direction), and the second frame (620) may be provided as a pair and positioned to face the electrode assembly (100) in a third direction (Y-axis direction) that is perpendicular to both the first direction (Z-axis direction) and the second direction (X-axis direction).

[0065] In one embodiment, a first frame (610) may be connected adjacent to one edge (hereinafter referred to as the first edge) of one electrode plate (200, 300), and a second frame (620) may be connected adjacent to another edge (hereinafter referred to as the second edge) extending from the first edge in a direction different from the first edge. For example, in one electrode plate (200, 300), the edges at both ends in the second direction (X-axis direction) may be the first edge, and the edges at both ends in the third direction (Y-axis direction) may be the second edge, and the first edge and the second edge may be connected to each other.

[0066] Alternatively, in various embodiments, the entire frame (600) of the bipolar cell (10) may be composed of a U-shaped subframe formed integrally with any two first frames (610) and one second frame (620), and the remaining second frame (620) coupled to the open end of the U-shaped subframe. However, the configuration of the entire frame (600) of the bipolar cell (10) is not limited to the above description, and may be formed in any structure that can cover at least one side of the electrode assembly (100) and maintain a spacing between the two electrode plates (200, 300).

[0067] In one embodiment, the frame (600) may include an insulating material so as to have sufficient rigidity to protect the electrode assembly (100) while being electrically insulated from the electrode plates (200, 300). For example, the frame (600) may include a polymer resin material such as polypropylene (PP) or polycarbonate (PC) or a non-conductive metal material.

[0068] In one embodiment, the first frame (610) and the second frame (620) may be joined to each other by an ultrasonic joining method or a thermal fusion joining method. However, in addition to the joining methods described above, any joining method may be applied as long as the first frame (610) and the second frame (620) can be firmly joined to each other.

[0069] The first electrode plate (200) and the second electrode plate (300) may be attached to different sides of the frame (600) and spaced apart from each other with the frame (600) in between. For example, referring to FIG. 4, the first electrode plate (200) may be attached to the lower side of the frame (600), and the second electrode plate (300) may be attached to the upper side of the frame (600).

[0070] In one embodiment, the electrode plates (200, 300) may be fused and joined to the frame (600). For example, referring to FIG. 4, the electrode plates (200, 300) and the frame (600) may be heat-fused to each other with a sealing member (631, 632) interposed between them. For example, the sealing member (631, 632) may include various polymer resin films, including polypropylene (PP) film. However, the material of the sealing member (631, 632) is not limited to what is described above, and any material capable of stably fixing the electrode plates (200, 300) and the frame (600) while maintaining airtightness may be applied without limitation.

[0071] In one embodiment, the sealing member (631, 632) may include a first sealing member (632) and a second sealing member (631) that are fused to different parts of the frame (600).

[0072] Referring to FIG. 4, a portion of the electrode plates (200, 300) may be positioned to face the frame (600) in a first direction (Z-axis direction), and a first sealing member (632) may be interposed therein.

[0073] Referring to FIG. 2 and FIG. 4 together, in one embodiment, a bent portion (210, 310) may be formed at the edge of the electrode plate (200, 300), which is a portion bent along the corner of the frame (600). For example, the two edges of the first electrode plate (200) in the second direction (X-axis direction) may be bent in a direction toward the second electrode plate (300) to form a first bent portion (210), and the two edges of the second electrode plate (300) in the second direction (X-axis direction) may be bent in a direction toward the first electrode plate (200) to form a second bent portion (310).

[0074] In FIG. 2, the bend portions (210, 310) are formed only on two parallel edges of the electrode plates (200, 300), but otherwise, the bend portions (210, 310) may be formed only on one edge of the electrode plates (200, 300), or on three edges connected to each other, or may be formed along all edges.

[0075] In this way, a fold portion (210, 310) is formed at the edge of the electrode plate (200, 300) and is wrapped around and joined to at least a part of the corner of the frame (600), thereby increasing the airtightness between the electrode plate (200, 300) and the frame (600). Additionally, when a plurality of bipolar cells (10) are stacked to form a cell stack, such a fold portion (210, 310) can be exposed to the outside from the side of the cell stack, and heat dissipation can be smoothly achieved through the exposed fold portion (210, 310), thereby increasing the cooling performance of the bipolar cell (10).

[0076] Referring to FIG. 4, the bent portions (210, 310) of the electrode plates (200, 300) may be positioned to face the frame (600) in a second direction (X-axis direction). The second sealing member (631) may seal the space between the bent portions (210, 310) and the frame (600) and fuse the bent portions (210, 310) and the frame (600) together.

[0077] In one embodiment, the electrode plates (200, 300) and the frame (600) may form a combined structure that is double-sealed through a first sealing member (632) and a second sealing member (631). Such a double-sealed combined structure can further increase the structural stability and airtightness of the bipolar cell (10).

[0078] In one embodiment, a protruding portion may be formed between the first bend portion (210) and the second bend portion (310) in the frame (600), and a second sealing member (631) may be formed to surround this protruding portion. Accordingly, a protrusion (611) that protrudes further outward than the first bend portion (210) and the second bend portion (310) may be formed on the side of the bipolar cell (10). Such a protrusion (611) can more reliably prevent the first bend portion (210) and the second bend portion (310) from coming into contact with each other.

[0079] Hereinafter, with reference to FIGS. 5 to 7, the method for manufacturing a bipolar cell (10) will be explained in more detail.

[0080] FIG. 5 is a reference diagram illustrating an exemplary method of manufacturing a bipolar cell (10) according to one embodiment.

[0081] FIG. 6 is a reference diagram exemplarily showing how an electrode assembly (100) is inserted into a frame (600) in a method for manufacturing a bipolar cell (10) according to one embodiment.

[0082] FIG. 7 is a reference diagram exemplarily showing the bending of the edges of electrode plates (200, 300) in a method for manufacturing a bipolar cell (10) according to one embodiment.

[0083] Since the bipolar cell (10) and its detailed configuration described in FIGS. 5 to 7 include all the features of the bipolar cell (10) and its detailed configuration described in FIGS. 1 to 4, descriptions that overlap with FIGS. 1 to 4 may be omitted.

[0084] A method for manufacturing a bipolar cell (10) may include a first electrode plate (200) coupling step of coupling a frame (600) containing an insulating material to the upper surface of a first electrode plate (200), an alignment step of placing an electrode assembly (100) on the upper surface of the first electrode plate (200), and a second electrode plate (300) coupling step in which the second electrode plate (300) is coupled to the frame (600) so as to cover the upper surface of the electrode assembly (100).

[0085] A method for manufacturing a bipolar cell (10) may further include a preparation step for preparing an electrode assembly (100) included in the bipolar cell (10). The preparation step may include a stacking step in which a plurality of bipolar electrodes (BE in FIG. 3), each having a first electrode layer (120 in FIG. 3) formed on one side of a current collector (110 in FIG. 3) and a second electrode layer (130 in FIG. 3) having a polarity opposite to that of the first electrode layer (120) formed on the other side of the current collector (110), and one or more separators (140 in FIG. 3) are alternately stacked along a first direction (Z-axis direction) to form an electrode stack (ES in FIG. 3), and a sealing step in which a sealing portion (150 in FIG. 3) is formed along the perimeter of the electrode stack (ES). For a detailed description of the electrode stack (ES) and the sealing portion (150), refer to FIG. 1 to FIG. 4. The electrode assembly (100) sealed by the sealing part (150) can be transferred by a transfer device (not shown) to a device that performs a process after the preparation step.

[0086] Referring to FIG. 5, the method for manufacturing a bipolar cell (10) will be explained in more detail.

[0087] Referring to the upper left of FIG. 5, in the first electrode plate (200) coupling step, the first subframe (SF1) can be coupled to the upper surface of the first electrode plate (200). For example, the first subframe (SF1) and the first electrode plate (200) can be coupled by mutual fusion with a first sealing member (632 in FIG. 7) interposed between them.

[0088] In one embodiment, the first subframe (SF1) may have a U-shaped structure. For example, referring to FIG. 5, the first subframe (SF1) may have a U-shaped structure in which a pair of second frames (620) are connected to both ends of the first frame (610). In such a first subframe (SF1), an opening may be formed between the ends of the pair of second frames (620) into which an electrode assembly (100) can be inserted.

[0089] Referring to the upper right of FIG. 5, during the alignment step, the electrode assembly (100) can be placed on the upper surface of the first electrode plate (200). For example, the electrode assembly (100) can be placed in the area of ​​the upper surface of the first electrode plate (200) surrounded by the first frame (610) and a pair of second frames (620). With the electrode assembly (100) placed in the correct position, the U-shaped first sub-frame (SF1) can cover three sides of the electrode assembly (100).

[0090] However, unlike as shown in FIG. 5, the electrode assembly (100) may slide along the upper surface of the first electrode plate (200) and be positioned in a fixed position on the upper surface of the first electrode plate (200). For example, referring to FIG. 6, the electrode assembly (100) may slide along the upper surface of the first electrode plate (200) through the opening of the U-shaped first subframe (SF1) and be positioned in the area of ​​the upper surface of the first electrode plate (200) surrounded by the first frame (610) and a pair of second frames (620). When both the first electrode plate (200) and the electrode assembly (100) have a flat structure, such a slide insertion process can be performed smoothly.

[0091] In one embodiment, during the process of placing the electrode assembly (100) on the first electrode plate (200), a position sensor or a vision sensor may be utilized to ensure accurate position alignment of the electrode assembly (100). For example, while a transfer device transfers the electrode assembly (100) and places it on the first electrode plate (200), the position sensor detects the position of the electrode assembly (100) in real time, and the electrode assembly (100) can be placed in an accurate position through feedback control that adjusts the position of the electrode assembly (100) based on the detected position information. Alternatively, the position sensor or a vision sensor may detect the position of the placed electrode assembly (100) and appropriately adjust the position of the electrode assembly (100) based on the detected position information to place the electrode assembly (100) in an accurate position.

[0092] Continuing, referring to the lower right side of FIG. 5, after the electrode assembly (100) is seated in the correct position through the alignment step, the second sub-frame (SF2) is joined to the first sub-frame (SF1) to block the opening of the first sub-frame (SF1). As the second sub-frame (SF2) and the first sub-frame (SF1) are joined together, a picture frame (600) can be formed. In joining the first sub-frame (SF1) and the second sub-frame (SF2), joining methods such as thermal fusion or laser fusion may be applied, but various other joining methods that can stably maintain the structure of the picture frame (600) may also be applied without limitation.

[0093] Additionally, the second electrode plate (300) can cover the upper surface of the electrode assembly (100) and be coupled to the frame (600). For example, the first subframe (SF1) or the second subframe (SF2) and the second electrode plate (300) can be coupled by mutual fusion with a first sealing member (632 in FIG. 7) interposed between them.

[0094] As the second electrode plate (300) is coupled to the frame (600), a structure is formed in which the electrode assembly (100) is accommodated in an internal receiving space surrounded by the first electrode plate (200), the frame (600), and the second electrode plate (300).

[0095] In one embodiment, the method for manufacturing a bipolar cell (10) may further include a first bending step of bending at least one edge of a first electrode plate (200) and a second bending step of bending at least one edge of a second electrode plate (300).

[0096] For example, referring to FIG. 7, a first bend portion (210) may be formed by bending one edge of the first electrode plate (200) to be in contact with the side of the frame (600), and a second bend portion (310) may be formed by bending one edge of the second electrode plate (300) to be in contact with the side of the frame (600). Here, the bend portion (210, 310) being in contact with the side of the frame (600) may mean that the bend portion (210, 310) is in contact with the frame (600) itself, or that it is in contact with the side of the frame (600) with another member interposed therein.

[0097] The first bend portion (210) and the second bend portion (310) can be spaced apart from each other in the first direction (Z-axis direction) with the protrusion (611) of the frame (600) in between.

[0098] A second sealing member (631) may be disposed on the side of the frame (600), and the first bend portion (210) and the second bend portion (310) may be fused to the frame (600) through the second sealing member (631).

[0099] Through the first and second bending steps, a bent portion (210, 310) can be formed on the electrode plate (200, 300), and the outer shape of the bipolar cell (10) can be completed as shown in the lower left of FIG. 5.

[0100] In various embodiments, the first bending step and the second bending step may be performed sequentially or simultaneously. Alternatively, if necessary, the bending portion (210, 310) may not be formed on the electrode plate (200, 300), in which case the first bending step or the second bending step may be omitted.

[0101] Meanwhile, in one embodiment, the method for manufacturing the bipolar cell (10) may further include an activation step for activating the electrode assembly (100).

[0102] The activation step is a step of activating the electrode assembly (100), which stabilizes the electrode assembly (100) and makes it usable. In the activation step, a charging process, an aging process, and a discharging process may be performed.

[0103] In one embodiment, the activation step may further include a degassing step for removing gas generated during activation of the electrode assembly (100).

[0104] When the degassing step is completed in this way, the bipolar cell (10) can be stably used.

[0105] In one embodiment, the activation step may be performed after the first electrode plate (200), the frame (600), and the second electrode plate (300) surround and are coupled to the electrode assembly (100). In this case, since cell fabrication proceeds in a state prior to activation of the electrode assembly (100), that is, in a state where a high level of voltage is not formed in the electrode assembly (100), various processes of the bipolar cell (10) manufacturing method can be safely performed.

[0106] However, in various embodiments, the activation step may be performed before the electrode assembly (100) is aligned on the first electrode plate (200). That is, the transfer device may transfer the electrode assembly (100), which has already been activated, and align it on the first electrode plate (200).

[0107] Hereinafter, with reference to FIG. 8, a method for manufacturing a bipolar cell (10) according to another embodiment will be described.

[0108] FIG. 8 is a reference diagram illustrating an exemplary method of manufacturing a bipolar cell (10) according to another embodiment.

[0109] Since the bipolar cell (10) described in FIG. 8 includes all the features of the bipolar cell (10) described in FIG. 1 to FIG. 4, descriptions that overlap with FIG. 1 to FIG. 4 may be omitted.

[0110] Referring to the upper left of FIG. 8, during the alignment step, the electrode assembly (100) may be placed on the upper surface of the first electrode plate (200). In this case, the electrode assembly (100) may be placed on the upper surface of the first electrode plate (200) before the frame (600) is attached. For example, the electrode assembly (100) may be moved in the -Z axis direction by a transfer device and placed on the upper surface of the first electrode plate (200). Alternatively, the electrode assembly (100) may be slid along the upper surface of the first electrode plate (200) and placed in a fixed position on the first electrode plate (200).

[0111] If necessary, a position sensor or a vision sensor may be utilized to accurately align the position of the electrode assembly (100) during the process of placing the electrode assembly (100) on the first electrode plate (200). For the method of aligning the electrode assembly (100) using a position sensor or a vision sensor, refer to the content previously described with respect to FIGS. 5 to 7.

[0112] Referring to the upper right of FIG. 8, after the electrode assembly (100) is seated in the correct position through an alignment step, a picture frame (600) can be attached to the upper surface of the first electrode plate (200). In this case, the picture frame (600) can be positioned to cover the entire perimeter of the electrode assembly (100), and can be attached to the first electrode plate (200) by fusing it with a first sealing member (632 in FIG. 7) interposed between it and the first electrode plate (200).

[0113] The picture frame (600) may be formed as a single integral member. Alternatively, the picture frame (600) may be formed by assembling the first frame (610) and the second frame (620) shown in FIG. 2 above. Alternatively, the picture frame (600) may be formed by assembling the first sub-frame (SF1) and the second sub-frame (SF2) shown in FIG. 5 above.

[0114] Referring to the lower right side of FIG. 8, the second electrode plate (300) can cover the upper surface of the electrode assembly (100) and be coupled to the frame (600). In coupling the second electrode plate (300), the same coupling method between the second electrode plate (300) and the frame (600) described above through FIG. 5 can be applied.

[0115] Meanwhile, the method for manufacturing a bipolar cell (10) according to the embodiment described in FIG. 8 may include a first bending step and a second bending step described above in FIG. 7, and a detailed description thereof may be made by referring to FIG. 7.

[0116] Meanwhile, in another embodiment, the method for manufacturing the bipolar cell (10) may further include an activation step for activating the electrode assembly (100).

[0117] In another embodiment, the activation step may be performed before the electrode assembly (100) is aligned on the first electrode plate (200). That is, the transfer device may transfer the electrode assembly (100), which has already been activated, and align it on the first electrode plate (200).

[0118] In this way, even if the electrode assembly (100) that has already been activated is placed on the first electrode plate (200), the bipolar cell (10) manufacturing process can be safely performed with the frame-type frame (600) stably wrapping the side of the electrode assembly (100). For example, the frame-type frame (600), which is manufactured as a single unit, can cover the perimeter of the activated electrode assembly (100) and sufficient structural rigidity can be secured, allowing subsequent processes to proceed, and accordingly, the bipolar cell (10) manufacturing process can be safely performed.

[0119] However, in various embodiments, the activation step may be performed after the first electrode plate (200), the frame (600), and the second electrode plate (300) surround and are coupled to the electrode assembly (100). In this case, since cell fabrication proceeds in a state prior to activation of the electrode assembly (100), that is, in a state where a high level of voltage is not formed in the electrode assembly (100), various processes of the bipolar cell (10) manufacturing method can be safely performed.

[0120] In another embodiment, the activation step may further include a degassing step for removing gas generated during activation of the electrode assembly (100).

[0121] When the degassing step is completed in this way, the bipolar cell (10) can be stably used.

[0122] Meanwhile, a bipolar cell (10) according to various embodiments of the present disclosure can be used as a power source for various electronic devices, and the battery device may be, for example, a laptop computer, a netbook, a tablet PC, a mobile phone, an MP3 player, a wearable electronic device, a power tool, an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric bicycle (E-bike), an electric scooter (E-scooter), an electric golf cart, or an energy storage system (ESS), but is not limited to these.

[0123] Although various embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be obvious to those with average knowledge in the art that various modifications and variations are possible within the scope of the technical concept of the present invention as described in the claims. Furthermore, the above-described embodiments may be implemented by deleting some components, and each embodiment may be implemented in combination with one another.

Claims

1. A preparation step for preparing an electrode assembly comprising a plurality of bipolar electrodes and a separator; A first electrode plate coupling step of coupling a frame including an insulating material to a first electrode plate; An alignment step of placing the electrode assembly on the upper surface of the first electrode plate; and A method for manufacturing a bipolar cell, comprising a second electrode plate coupling step in which the second electrode plate is coupled to the frame so as to cover the upper surface of the electrode assembly.

2. In Paragraph 1, The above preparation step A stacking step of forming an electrode stack by alternately stacking the plurality of bipolar electrodes and the separator; and A method for manufacturing a bipolar cell, comprising a sealing step in which a sealing portion is formed to seal the electrode stack along the perimeter of the electrode stack.

3. In Paragraph 1, In the first electrode plate coupling step, A first subframe having an opening formed on at least one side is coupled to the first electrode plate, and In the above alignment step, A method for manufacturing a bipolar cell, wherein the electrode assembly is slidably inserted along the upper surface of the first electrode plate through the opening.

4. In Paragraph 3, A method for manufacturing a bipolar cell, wherein, after the above alignment step, a second subframe is coupled to the first subframe to close the opening.

5. In Paragraph 3, A method for manufacturing a bipolar cell, which is performed after the second electrode plate coupling step and further includes an activation step for activating the electrode assembly.

6. In Paragraph 1, A method for manufacturing a bipolar cell, wherein a first sealing member is interposed between one side of the frame and the first electrode plate or between the other side of the frame and the second electrode plate.

7. In Paragraph 1, The first electrode plate coupling step is performed after the alignment step, and A method for manufacturing a bipolar cell, wherein, in the first electrode plate coupling step, the frame is positioned along the four sides of the electrode assembly.

8. In Paragraph 7, A method for manufacturing a bipolar cell, wherein the above-mentioned frame has an integrated picture frame structure.

9. In Paragraph 7, A method for manufacturing a bipolar cell, wherein the above preparation step includes an activation step for activating the electrode assembly.

10. In Paragraph 1, A method for manufacturing a bipolar cell, further comprising a first bending step of bending at least one edge of the first electrode plate to be attached to the side of the frame.

11. In Paragraph 10, It further includes a second bending step of bending one edge of the second electrode plate to be attached to the side of the frame, and A method for manufacturing a bipolar cell, wherein a first bent portion of the first electrode plate and a second bent portion of the second electrode plate are spaced apart from each other in the stacking direction of the electrode assembly.

12. In Paragraph 11, A method for manufacturing a bipolar cell, wherein the first bend portion and the second bend portion are spaced apart from each other with the protrusion of the frame in between.

13. In Paragraph 12, A second sealing member is disposed on the side of the above frame, and A method for manufacturing a bipolar cell, wherein the first bend portion and the second bend portion are fused to the frame via the second sealing member.

14. In Paragraph 1, The above frame is A first frame coupled to the first edge of the first electrode plate; and It includes a second frame coupled to a second edge extending in a direction different from the first edge of the first electrode plate, and A method for manufacturing a bipolar cell in which the first frame and the second frame are ultrasonically fused or thermally fused to each other.

15. An electrode assembly comprising a plurality of bipolar electrodes and a separator; A first electrode plate positioned to face one side of the electrode assembly; A second electrode plate disposed facing the opposite side of the one side of the electrode assembly; and A bipolar cell comprising a frame disposed along the edge of the electrode assembly between the first electrode plate and the second electrode plate.

Images