Power storage cell

Abstract

The capacitor cell comprises a wound electrode body including a positive electrode plate (first electrode), a negative electrode plate (second electrode), and a separator. The positive electrode plate comprises a positive electrode current collector (first current collector) and a positive electrode composite layer (first electrode material layer). The positive electrode current collector has a positive electrode coating portion (first coating portion) and a plurality of positive electrode non-coating portions (first non-coating portions) installed to protrude from the positive electrode coating portion on one side of the axial direction of the wound electrode body. Some of the positive electrode non-coating portions among the plurality of positive electrode non-coating portions are arranged side by side in a spaced-away state in the X direction (winding direction).

Description

Technology Field

[0001] The present disclosure relates to a capacitor cell. Background Technology

[0002] Japanese Patent Publication No. 4805545 discloses a lithium secondary battery having a wound-type internal electrode body composed of a positive electrode metal foil and a negative electrode metal foil interposed with a separator. The internal electrode body has a tabless structure by being installed so that the ends of the metal foils (positive electrode, negative electrode) contact a current collecting member (positive electrode, negative electrode). The ends of the metal foils protrude between the separators. The problem to be solved

[0003] In the internal electrode body of the above-mentioned Japanese Patent Publication No. 4805545, the end of the metal foil in contact with the current collector protrudes between the separators, so the separator is covered by said end. For this reason, when an electrolyte is injected into the internal electrode body in a wound state, the flow of the electrolyte is obstructed by said end, and it may be difficult to penetrate the electrolyte into the separator.

[0004] The present disclosure is made to solve the above problem, and its purpose is to provide a capacitor cell capable of efficiently penetrating an electrolyte into a separator of a wound electrode body. means of solving the problem

[0005] A capacitor cell according to one aspect of the present disclosure comprises a wound electrode body including a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode, and a case for housing the wound electrode body. The first electrode comprises a first current collector and a first electrode material layer that is coated on a part of the first current collector and faces the separator in the diameter direction of the wound electrode body. The first current collector has a first coated portion where the first electrode material layer is coated, and a plurality of first uncoated portions located on one side of the axial direction of the wound electrode body and where the first electrode material layer is not coated. The plurality of first uncoated portions are arranged parallel to each other in the winding direction of the wound electrode body. At least some of the first uncoated portions among the plurality of first uncoated portions are arranged parallel to each other in the winding direction while being spaced apart from each other.

[0006] In a capacitor cell according to one aspect of the present disclosure, as described above, at least some of the first uncoated portions among the plurality of first uncoated portions are arranged side by side in a spaced-apart manner in the winding direction. Accordingly, when an electrolyte is injected into the wound electrode body, the gap between the first uncoated portions can be used as an injection route for the electrolyte. As a result, the electrolyte can be efficiently infiltrated into the separator of the wound electrode body.

[0007] In the capacitor cell according to the above-described phase, preferably, the wound electrode body comprises, when viewed from one side in the axial direction, a coated portion covered by a first uncoated portion and an uncoated portion not covered by the first uncoated portion. With this configuration, when an electrolyte is injected into the wound electrode body, the uncoated portion can be used as an injection route for the electrolyte. As a result, the electrolyte can be penetrated more efficiently into the separator of the wound electrode body.

[0008] In this case, preferably, a plurality of first uncoated portions are arranged along the diameter direction of the wound electrode body when viewed from one side in the axial direction. By configuring it in this way, compared to the case where the first uncoated portions are arranged in the circumferential direction, it is possible to suppress the obstruction of the electrolyte moving in the diameter direction by the first uncoated portions when the electrolyte is injected into the wound electrode body.

[0009] In the capacitor cell according to the above phase, the distance between the first uncoated portions, which are preferably spaced apart in the winding direction, gradually increases toward the end of the winding direction. By configuring it in this way, it is possible to facilitate the injection of the electrolyte from the outer side in the diameter direction of the winding electrode body (end of the winding side).

[0010] In the capacitor cell according to the above-described phase, preferably, the first uncoated portions disposed on the outer periphery of the wound electrode body are arranged side by side in an adjacent state in the winding direction. By configuring it in this way, the first uncoated portions can be densely arranged on the outer periphery of the wound electrode body.

[0011] In the capacitor cell according to the above-described phase, preferably, the second electrode comprises a second current collector and a second electrode material layer that is coated on a part of the second current collector and faces the separator in the diameter direction. The second current collector has a second coated portion coated with the second electrode material layer and a plurality of second uncoated portions located on the axial opposite side of the wound electrode body from the second coated portion and not coated with the second electrode material layer. The plurality of second uncoated portions are arranged parallel to each other in the winding direction. At least some of the second uncoated portions among the plurality of second uncoated portions are arranged parallel to each other in the winding direction while being spaced apart from each other. With this configuration, the electrolyte can be flowed from the second electrode side to the separator through the gap between the second uncoated portions.

[0012] According to the present disclosure, an electrolyte can be efficiently infiltrated into the separator of a wound electrode body.

[0013] The above and other objects, features, aspects, and advantages of the present invention will become clear from the following detailed description of the present invention as understood in conjunction with the accompanying drawings. Brief explanation of the drawing

[0014] FIG. 1 is a cross-sectional view showing the configuration of a capacitor cell according to one embodiment. Figure 2 is a magnified view of the positive pole side of Figure 1. Figure 3 is a magnified view of the negative side of Figure 1. FIG. 4 is a plan view showing the configuration of a positive electrode current collector according to one embodiment. Figure 5 is a diagram showing the relationship between the distance between the positive and negative poles and their positions in the winding direction. FIG. 6 is a plan view of a wound electrode body according to one embodiment, viewed from the Z1 side. FIG. 7 is a plan view showing the configuration of a negative electrode current collector according to one embodiment. Figure 8 is a diagram showing the relationship between the distance between the negative poles and the position in the winding direction. FIG. 9 is a plan view of a wound electrode body according to one embodiment, viewed from the Z2 side. FIG. 10 is a plan view showing the configuration of a positive electrode current collector according to a modified example of one embodiment. Specific details for implementing the invention

[0015] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In addition, identical or substantial parts in the drawings are denoted by the same reference numerals, and their descriptions will not be repeated.

[0016] FIG. 1 is a cross-sectional view showing the overall configuration of a storage cell (100) according to an embodiment of the present disclosure. The storage cell (100) is, for example, a lithium-ion battery mounted in a vehicle. In addition, the use and type of the storage cell (100) are not limited to the above examples.

[0017] The capacitor cell (100) comprises a wound electrode body (1), a case (2), a positive electrode terminal (3), a positive electrode collector plate (4), an external gasket (5), an internal gasket (6), and a negative electrode collector plate (7).

[0018] The wound electrode body (1) is housed in a case (2). The case (2) has a cylindrical shape. That is, the capacitor cell (100) is a cylindrical battery. In addition, the case (2) is formed of copper or aluminum, etc.

[0019] The wound electrode body (1) includes a positive electrode plate (10), a negative electrode plate (20), and a separator (30). The separator (30) is provided between the positive electrode plate (10) and the negative electrode plate (20). The separator (30) separates the positive electrode plate (10) and the negative electrode plate (20) while enabling the movement of ions (e.g., lithium ions) between the positive electrode plate (10) (positive active material) and the negative electrode plate (20) (negative active material). The wound electrode body (1) is composed of a group of electrode plates in which the positive electrode plate (10) and the negative electrode plate (20) are wound with the separator (30) interposed. Additionally, the positive electrode plate (10) and the negative electrode plate (20) are each examples of the "first electrode" and "second electrode" of the present disclosure.

[0020] The positive terminal (3) includes a disk portion (3a) and a rivet portion (3b). The rivet portion (3b) is connected to the disk portion (3a). The rivet portion (3b) is provided to extend from the center of the disk portion (3a) toward the Z2 side. Additionally, the positive terminal (3) is formed of aluminum.

[0021] The disc portion (3a) is positioned on the upper surface (2a) (Z1 side surface) of the case (2). A through hole (2b) (see FIG. 2) is provided on the upper surface (2a) of the case (2). The rivet portion (3b) extends from the disc portion (3a), which is positioned on the outside of the case (2), through the through hole (2b) to the inside of the case (2).

[0022] The positive electrode collector plate (4) is housed in the case (2). The positive electrode collector plate (4) is welded to the positive electrode uncoated portion (11b) described later on the Z1 side of the wound electrode body (1). By this, the positive electrode collector plate (4) is positively charged. The positive electrode collector plate (4) is welded to the end (3c) on the Z2 side of the rivet portion (3b) (see FIG. 2). By this, the positive electrode terminal (3) is positively charged.

[0023] The external gasket (5) is positioned between the disk portion (3a) of the positive terminal (3) and the upper surface (2a) of the case (2). By doing so, the positive terminal (3) and the case (2) are insulated.

[0024] The internal gasket (6) is positioned inside the case (2) between the case (2) and the positive electrode collector plate (4). As a result, the case (2) and the positive electrode collector plate (4) are insulated. Additionally, the rivet portion (3b) is in contact with the positive electrode collector plate (4) by penetrating the internal gasket (6).

[0025] The negative electrode collector plate (7) is housed in the case (2). The negative electrode collector plate (7) is welded to the negative electrode uncoated portion (21b) described later on the negative electrode plate (20) on the Z2 side of the wound electrode body (1). By this, the negative electrode collector plate (7) is negatively charged. Additionally, the negative electrode collector plate (7) is in contact with the case (2). By this, the case (2) is negatively charged.

[0026] As illustrated in FIG. 2, the positive electrode plate (10) includes a positive electrode current collector (11) and a positive electrode composite layer (12). The positive electrode composite layer (12) is coated on both sides in the diameter direction (R direction) of the positive electrode current collector (11). The positive electrode composite layer (12) faces the separator (30) in the R direction. Additionally, the positive electrode current collector (11) and the positive electrode composite layer (12) are examples of the "first current collector" and the "first electrode material layer," respectively.

[0027] For the positive electrode current collector (11), materials such as aluminum are used. The positive electrode composite layer (12) is formed by coating a positive electrode slurry onto the surface of the positive electrode current collector (11) and drying it. The positive electrode slurry is a slurry prepared by mixing a solvent with a material of the positive electrode composite layer (12) (positive electrode active material, binder, etc.). The positive electrode composite layer (12) is in close contact with the separator (30). The thickness of the positive electrode composite layer (12) is, for example, 0.1 μm or more and 1000 μm or less.

[0028] The positive electrode current collector (11) includes a positive electrode coated portion (11a) and a plurality of positive electrode uncoated portions (11b). The positive electrode coated portion (11a) is a portion of the positive electrode current collector (11) where the positive electrode composite layer (12) is coated. The positive electrode coated portion (11a) is interposed between the separators (30). Additionally, the positive electrode coated portion (11a) and the positive electrode uncoated portion (11b) are each examples of the “first coated portion” and “first uncoated portion” of the present disclosure.

[0029] Each of the plurality of positive electrode uncoated portions (11b) is located on the Z1 side relative to the positive electrode coated portion (11a). Specifically, each of the plurality of positive electrode uncoated portions (11b) protrudes from the positive electrode coated portion (11a) toward the Z1 side. The plurality of positive electrode uncoated portions (11b) are arranged in parallel in the winding direction of the wound electrode body (1). Each of the plurality of positive electrode uncoated portions (11b) is a portion of the positive electrode current collector (11) where the positive electrode composite layer (12) is not coated. Furthermore, the Z1 side is an example of the "axial direction one side" of the present disclosure.

[0030] Each of the plurality of positive electrode coating portions (11b) includes a portion (11c) extending along the Z direction and a portion (11d) extending along the R direction. That is, each of the plurality of positive electrode coating portions (11b) is bent into an L-shape. Each portion (11d) of the plurality of positive electrode coating portions (11b) is in contact with the positive electrode collector plate (4). As a result, the positive electrode collector plate (4) is positively charged. In addition, the positive electrode coating portions (11b) (parts (11d)) are joined to the positive electrode collector plate (4) by welding.

[0031] In addition, the positive electrodes (11b) adjacent to the R direction are arranged so that their respective parts (11d) partially overlap each other.

[0032] As illustrated in FIG. 3, the negative electrode plate (20) includes a negative electrode current collector (21) and a negative electrode composite layer (22). The negative electrode composite layer (22) is coated on both sides in the diameter direction (R direction) of the negative electrode current collector (21). That is, the negative electrode composite layer (22) faces the separator (30) in the R direction. In addition, the negative electrode current collector (21) and the negative electrode composite layer (22) are each examples of the "second current collector" and "second electrode material layer" of the present disclosure.

[0033] For the negative electrode current collector (21), for example, copper is used. The negative electrode composite layer (22) is formed by coating the surface of the negative electrode current collector (21) with a negative electrode slurry and drying it. The negative electrode slurry is a slurry prepared by mixing a solvent with the material of the negative electrode composite layer (22) (such as a negative electrode active material or binder). The negative electrode composite layer (22) is in close contact with the separator (30). The thickness of the negative electrode composite layer (22) is, for example, 0.1 μm or more and 1000 μm or less.

[0034] The negative electrode current collector (21) includes a negative electrode coated portion (21a) and a plurality of negative electrode uncoated portions (21b). The negative electrode coated portion (21a) is a portion of the negative electrode current collector (21) where the negative electrode composite layer (22) is coated. The negative electrode coated portion (21a) is interposed between the separators (30). Additionally, the negative electrode coated portion (21a) and the negative electrode uncoated portion (21b) are each examples of the “second coated portion” and “second uncoated portion” of the present disclosure.

[0035] Each of the plurality of negative electrode uncoated portions (21b) is located on the Z2 side relative to the negative electrode coated portion (21a). Specifically, each of the plurality of negative electrode uncoated portions (21b) protrudes from the negative electrode coated portion (21a) toward the Z2 side. The plurality of negative electrode uncoated portions (21b) are arranged parallel to each other in the winding direction of the wound electrode body (1). Additionally, each of the plurality of negative electrode uncoated portions (21b) is a portion of the negative electrode current collector (21) where the negative electrode composite layer (22) is not coated. Furthermore, the Z2 side is an example of the "axial opposite side" of the present disclosure.

[0036] Each of the plurality of negative electrode uncoated portions (21b) includes a portion (21c) extending along the Z direction and a portion (21d) extending along the R direction. That is, each of the plurality of negative electrode uncoated portions (21b) is bent into an L shape. Each portion (21d) of the plurality of negative electrode uncoated portions (21b) is in contact with the negative electrode collector plate (7). As a result, the negative electrode collector plate (7) is negatively charged. In addition, the negative electrode uncoated portions (21b) (parts (21d)) are joined to the negative electrode collector plate (7) by welding.

[0037] In addition, the negative electrode uncoated portions (21b) adjacent to the R direction are arranged so that their respective portions (21d) partially overlap each other.

[0038] Here, in the configuration of a conventional capacitor cell, since the separator is covered by the aforementioned uncoated portion, when the electrolyte is injected into the wound electrode body in a wound state, the flow of the electrolyte is obstructed by the uncoated portion. For this reason, it may be difficult to penetrate the electrolyte into the separator.

[0039] Accordingly, in this embodiment, as shown in FIG. 4, some of the positive electrode uncoated portions (11b) among the plurality of positive electrode uncoated portions are arranged side by side in a spaced-apart state in the X direction. FIG. 4 is a plan view of the positive electrode current collector (11) in an unwound state, viewed from the Y2 side. FIG. 4 also shows the positive electrode uncoated portion (11b) in a state where it is not bent. In addition, the X direction is a direction corresponding to the "winding direction" (R direction of FIG. 1, etc.) of the present disclosure. In addition, the X1 direction corresponds to the winding start side in the winding direction. The X2 direction corresponds to the winding end side in the winding direction.

[0040] Specifically, a plurality of positive electrode coating portions (11b), excluding the positive electrode coating portion (11b) corresponding to the outer circumference (1a) of the coiled electrode body (1), are arranged in parallel in the X direction with a distance D1 between them. In other words, a gap S1 is provided between the positive electrode coating portions (11b) adjacent in the X direction (excluding the positive electrode coating portion (11b) corresponding to the outer circumference (1a). Hereinafter, when simply referred to as a positive electrode coating portion (11b), it shall be understood to refer to a positive electrode coating portion (11b) other than the positive electrode coating portion (11b) corresponding to the outer circumference (1a).

[0041] In this embodiment, the distance D1 between the positive electrode uncoated portions (11b) spaced apart in the X direction gradually increases toward the winding end side (X2 side) in the winding direction. That is, the gap S1 between the positive electrode uncoated portions (11b) gradually increases toward the winding end side. For example, the distance D1 may increase linearly (in a linear function) toward the winding end side (see FIG. 5). Additionally, the distance D1 may increase quadratically toward the winding end side.

[0042] FIG. 6 is a view of the wound electrode body (1) from the Z1 side (positive electrode side). As shown in FIG. 6, a plurality of positive electrode uncoated portions (11b) are arranged along the diameter direction (R direction in FIG. 2) of the wound electrode body (1) when viewed from the Z1 side. In the example shown in FIG. 6, four diameter direction arrangement portions (11e) are formed by the plurality of positive electrode uncoated portions (11b) arranged along the diameter direction. Each of the four diameter direction arrangement portions (11e) is provided to extend outward in the diameter direction from the center O of the wound electrode body (1). Additionally, the diameter direction arrangement portions (11e) are examples of the "coating portions" of the present disclosure.

[0043] Adjacent diameter-direction array sections (11e) in the circumferential direction (C direction) of the coiled electrode body (1) are arranged with an angle of about 90 degrees between them. That is, adjacent diameter-direction array sections (11e) in the C direction are arranged to be orthogonal to each other. As a result, a plurality of positive electrode uncoated sections (11b) are arranged in a cross shape (X shape) when viewed from the Z1 side.

[0044] When viewing the wound electrode body (1) from the Z1 side, a gap region S11 is provided between adjacent diameter-direction array portions (11e) in the C direction. The gap region S11 is formed by the accumulation of gaps S1 (see FIG. 4) between adjacent positive electrode uncoated portions (11b) in the winding direction. Additionally, the gap region S11 is an example of the “uncoated portion” of the present disclosure.

[0045] Referring to FIGS. 4 and 6, positive electrode uncoated portions (11b) disposed on the outer circumference (1a) of the wound electrode body (1) are arranged in parallel in an adjacent state in the winding direction. As shown in FIG. 6, when viewing the wound electrode body (1) from the Z1 side, an outer circumference covering portion (11f) covering the outer circumference (1a) is formed by a plurality of positive electrode uncoated portions (11b) disposed on the outer circumference (1a). That is, the outer circumference covering portion (11f) covers the outer circumference (1a) of the wound electrode body (1) from the Z1 side. The outer circumference covering portion (11f) has a circular shape. Furthermore, the outer circumference covering portion (11f) is an example of the "covering portion" of the present disclosure.

[0046] Additionally, a plurality of negative electrode coating portions (21b) are arranged in the same manner as the positive electrode coating portion (11b). Specifically, as shown in FIG. 7, some of the negative electrode coating portions (21b) among the plurality of negative electrode coating portions (21b) are arranged side by side in a spaced-away state in the X direction. FIG. 7 is a plan view of the negative electrode current collector (21) in an unwound state, viewed from the Y2 side. Also, FIG. 7 shows a state in which the negative electrode coating portion (21b) is not bent or folded.

[0047] A plurality of negative electrode coating portions (21b), excluding the negative electrode coating portion (21b) corresponding to the outer circumference (1a) of the coiled electrode body (1), are arranged in parallel in the X direction with a distance D2 between them. In other words, a gap S2 is provided between the negative electrode coating portions (21b) adjacent in the X direction (excluding the negative electrode coating portion (21b) corresponding to the outer circumference (1a). Additionally, the distance D2 may be equal to the distance D1 between the positive electrode coating portions (11b) (see FIG. 4). In the following, when simply referred to as a negative electrode coating portion (21b), it refers to a negative electrode coating portion (21b) other than the negative electrode coating portion (21b) corresponding to the outer circumference (1a).

[0048] The distance D2 between the negative electrode uncoated portions (21b) spaced apart in the X direction gradually increases toward the winding end side (X2 side) in the winding direction. That is, the gap S2 between the negative electrode uncoated portions (21b) gradually increases toward the winding end side. For example, the distance D2 may increase linearly (in a linear function) toward the winding end side (see FIG. 8). Also, the rate (slope) at which the distance D2 gradually increases may be equal to the rate (slope) at which the distance D1 gradually increases. Additionally, the distance D2 may increase quadratically toward the winding end side.

[0049] FIG. 9 is a view of the wound electrode body (1) seen from the Z2 side. As shown in FIG. 9, a plurality of negative electrode uncoated portions (21b) are arranged along the diameter direction (R direction in FIG. 2) of the wound electrode body (1) when viewed from the Z2 side. In the wound electrode body (1), four diameter direction arrangement portions (21e) are formed by the negative electrode uncoated portions (21b) arranged along the diameter direction. Each of the four diameter direction arrangement portions (11e) is provided to extend outward in the diameter direction from the center O of the wound electrode body (1).

[0050] In the circumferential direction (C direction), adjacent diameter-direction array sections (21e) are arranged with an angle of approximately 90 degrees between them. That is, adjacent diameter-direction array sections (21e) in the C direction are arranged to be orthogonal to each other. As a result, a plurality of negative electrode uncoated sections (21b) are arranged in a cross shape (X shape) when viewed from the Z2 side. Additionally, although not illustrated, the diameter-direction array section (21e) may be arranged in a position that overlaps with the diameter-direction array section (11e) on the positive electrode side in the Z direction.

[0051] When viewing the wound electrode body (1) from the Z2 side, a gap region S21 is provided between adjacent diameter-direction array portions (21e) in the C direction. The gap region S21 is formed by the accumulation of gaps S2 (see FIG. 7) between adjacent negative electrode uncoated portions (21b) in the winding direction.

[0052] Referring to FIGS. 7 and 9, the negative electrode uncoated portions (21b) disposed on the outer circumference (1a) of the wound electrode body (1) are arranged in parallel in an adjacent state in the winding direction. As shown in FIG. 9, when viewing the wound electrode body (1) from the Z2 side, an outer circumference covering portion (21f) covering the outer circumference (1a) is formed by the plurality of negative electrode uncoated portions (21b) disposed on the outer circumference (1a). That is, the outer circumference covering portion (21f) covers the outer circumference (1a) of the wound electrode body (1) from the Z2 side. The outer circumference covering portion (21f) has a circular shape.

[0053] As described above, in this embodiment, some of the positive electrode uncoated portions (11b) among the plurality of positive electrode uncoated portions (11b) are arranged in parallel while spaced apart from each other in the winding direction of the wound electrode body (1). By doing so, a gap S1 is provided between the positive electrode uncoated portions (11b). As a result, when the wound electrode body (1) is formed, a gap region S11 can be formed as a route for injecting the electrolyte. By doing so, the electrolyte can be efficiently infiltrated into the separator (30). Furthermore, since the electrolyte can be easily injected, the injection of the electrolyte can be suppressed even if the charge amount (volume) of the electrode active material is increased. As a result, the energy density in the capacitor cell (100) can be improved by increasing the charge amount of the electrode active material.

[0054] In addition, since a gap region S11 is formed, when the internal pressure of the cell rises due to gas generated in the capacitor cell (100), the gas can be efficiently discharged (the rise in internal pressure of the cell can be alleviated) through the gap region S11.

[0055] In the above embodiment, an example is shown in which a plurality of positive electrode coating parts (11b), other than the positive electrode coating part (11b) corresponding to the outer circumference (1a), are arranged side by side in a spaced-away state in the winding direction, but the present disclosure is not limited to this. For example, as shown in FIG. 10, a group formed by a plurality (two in FIG. 10) of positive electrode coating parts (11b) adjacent in the winding direction may be arranged side by side in a spaced-away state in the winding direction. In addition, the above group formed by a plurality of positive electrode coating parts (11b) and a single positive electrode coating part (11b) may be arranged spaced apart (alternately) in the winding direction. In addition, a negative electrode coating part (21b) may also be arranged in the same manner as above.

[0056] In the above embodiment, an example is shown in which a plurality of positive electrode uncoated portions (11b) are arranged along the diameter direction when viewed from the Z1 side, but the present disclosure is not limited thereto. If an area not covered by the positive electrode uncoated portions (11b) is formed when viewing the wound electrode body (1) from the Z1 side, a plurality of positive electrode uncoated portions (11b) may be arranged, for example, along the circumference direction. Additionally, negative electrode uncoated portions (21b) may also be arranged in the same manner as above.

[0057] In the above embodiment, an example was shown in which the distance D1 between the positive electrode uncoated portions (11b) arranged parallel to each other in a spaced-apart state in the winding direction gradually increases toward the end of winding in the winding direction, but the present disclosure is not limited to this. For example, the distance D1 may be constant regardless of the position in the winding direction. In addition, the distance D1 may gradually decrease toward the end of winding. In addition, the negative electrode uncoated portions (21b) may also be arranged in the same manner as above.

[0058] In the above embodiment, an example has been shown in which the positive electrode uncoated portions (11b) disposed on the outer circumference (1a) of the wound electrode body (1) are arranged side by side in a state adjacent to each other in the winding direction, but the present disclosure is not limited thereto. The positive electrode uncoated portions (11b) disposed on the outer circumference (1a) of the wound electrode body (1) may be arranged side by side in a state spaced apart from each other in the winding direction. In addition, the negative electrode uncoated portions (21b) may also be arranged in the same manner as above.

[0059] In the above embodiment, an example is shown in which both positive electrode coating parts (11b) and negative electrode coating parts (21b) are arranged side by side while spaced apart from each other in the winding direction, but the present disclosure is not limited thereto. Only one of the positive electrode coating parts (11b) and negative electrode coating parts (21b) may be arranged side by side while spaced apart from each other in the winding direction.

[0060] Although embodiments of the present invention have been described, the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, and all modifications within the meaning and scope equivalent to the claims are intended to be included.

Claims

Claim 1 A wound electrode body comprising a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode, and a case for housing the wound electrode body; the first electrode comprises a first current collector and a first electrode material layer that is coated on a part of the first current collector and faces the separator in the diameter direction of the wound electrode body; the first current collector comprises a first coated portion coated with the first electrode material layer and a plurality of first uncoated portions located on one side of the axial direction of the wound electrode body from the first coated portion and in which the first electrode material layer is not coated; the plurality of first uncoated portions are arranged parallel to each other in the winding direction of the wound electrode body; at least some of the first uncoated portions among the plurality of first uncoated portions are arranged parallel to each other in the winding direction while being spaced apart from each other; and the first uncoated portions disposed on the outer periphery of the wound electrode body are adjacent to each other in the winding direction. Capacitor cells arranged side by side in a state. Claim 2 In claim 1, the above-mentioned coiled electrode body comprises, when viewed from one side in the axial direction, a coated portion covered by the first uncoated portion and an uncoated portion not covered by the first uncoated portion, forming a capacitor cell. Claim 3 In paragraph 2, the plurality of first uncoated portions are capacitor cells arranged along the diameter direction. Claim 4 A capacitor cell according to any one of claims 1 to 3, wherein the distance between the first uncoated parts spaced apart in the winding direction gradually increases toward the end of the winding direction. Claim 5 delete Claim 6 A capacitor cell according to any one of claims 1 to 3, wherein the second electrode comprises a second current collector and a second electrode material layer facing the separator in the diameter direction, which is coated on a part of the second current collector, and the second current collector has a second coated portion where the second electrode material layer is coated, and a plurality of second uncoated portions where the second electrode material layer is not coated, which are located on the axial opposite side of the wound electrode body from the second coated portion, and the plurality of second uncoated portions are arranged parallel to each other in the winding direction, and at least some of the second uncoated portions among the plurality of second uncoated portions are arranged parallel to each other in the winding direction while being spaced apart from each other.

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