Wound electrode assembly manufacturing apparatus and battery cell manufacturing method

Abstract

To provide a manufacturing apparatus for a wound electrode assembly capable of manufacturing a highly reliable electrode assembly, and a manufacturing method for a battery cell including the electrode assembly.SOLUTION: In a manufacturing apparatus for a wound electrode assembly 1, a conveying mechanism 300 provided on the outer peripheral surface of a winding core body 100 moves the wound electrode assembly 1 along a first direction at a speed that offsets the movement of the winding core body 100 in the first direction by a first driving unit 200, and a second driving unit 400 that drives the conveying mechanism 300 is located closer to the tip of the winding core body 100 than the first driving unit 200.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present technology relates to an apparatus for manufacturing a wound electrode body and a method for manufacturing a battery cell. [Background technology]

[0002] Conventionally, an electrode wound body is produced by stacking an electrode sheet and a separator on a winding core and winding them. For example, JP 2009-259722 A (Patent Document 1) discloses that when the produced electrode wound body is removed from the winding core, the electrode body is held by a chuck claw to suppress the occurrence of removal slippage (winding slippage). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-259722 A [Patent Document 2] International Publication No. 2018 / 025785 [Patent Document 3] JP 2014-133652 A [Patent Document 4] JP 2012-182046 A [Patent Document 5] JP 2003-17110 A [Patent Document 6] JP 2015-5390 A [Patent Document 7] JP 2002-222645 A Summary of the Invention [Problem to be solved by the invention]

[0004] Although a certain degree of effect of suppressing the occurrence of miswinding by gripping the electrode body can be expected, the electrode surface of the gripped electrode body may be unintentionally affected. From the viewpoint of manufacturing a highly reliable electrode body, there is room for improvement in the conventional technology.

[0005] An object of the present technology is to provide a manufacturing apparatus for a wound type electrode assembly capable of manufacturing a highly reliable electrode assembly, and a manufacturing method for a battery cell including the electrode assembly. [Means for solving the problem]

[0006] The present technology provides the following wound electrode assembly manufacturing apparatus and battery cell manufacturing method.

[0007] [1] An apparatus for manufacturing a wound type electrode body, the apparatus comprising: a core body having an outer circumferential surface and extending in a first direction; a first drive unit that is capable of rotating the core body about an axis in the first direction when winding the wound type electrode body and moving the core body along the first direction when removing the wound type electrode body; a transport mechanism provided on the outer circumferential surface of the core body and capable of moving the wound type electrode body wound on the outer circumferential surface in a direction opposite to the first direction; and a second drive unit that drives the transport mechanism, wherein the transport mechanism moves the wound type electrode body in the direction opposite to the first direction at a speed that offsets the movement of the core body in the first direction by the first drive unit, and the second drive unit that drives the transport mechanism is located closer to the tip of the core body than the first drive unit.

[0008] [2] The manufacturing apparatus for a wound electrode body described in [1], wherein the transport mechanism includes a chain-shaped member provided on the outer circumferential surface of the core body.

[0009] [3] The manufacturing apparatus for a wound electrode body described in [1], wherein the transport mechanism includes a belt-shaped member provided on the outer circumferential surface of the core body.

[0010] [4] The manufacturing apparatus for a wound electrode body described in any one of [1] to [3], wherein the conveying mechanism is provided in plurality so as to be aligned in the circumferential direction of the outer circumferential surface of the core body.

[0011] [5] A method for manufacturing a battery cell, comprising the steps of: manufacturing a wound type electrode body using a wound type electrode body manufacturing apparatus described in any one of [1] to [4]; electrically connecting an electrode terminal and the wound type electrode body; housing the wound type electrode body in an outer casing; and sealing the outer casing in which the wound type electrode body is housed. Effect of the Invention

[0012] According to the present technology, there is no need to grasp the electrode winding body with a chuck or the like when removing the electrode winding body wound around the core body, and the impact on the electrode surface can be reduced, making it possible to manufacture a highly reliable electrode body. [Brief description of the drawings]

[0013] [Figure 1] FIG. 13 is a diagram showing a state in which the electrode body is wound using a manufacturing device for a wound type electrode body. [Diagram 2] FIG. 2 is a diagram showing the configuration of a manufacturing apparatus for a wound electrode body. [Diagram 3] 1A and 1B are diagrams showing an example of a core body and a transport mechanism provided on the outer circumferential surface of the core body; [Figure 4] FIG. 13 is a diagram showing a modified example of the transport mechanism (part 1). [Diagram 5] FIG. 13 is a diagram (part 2) showing a modified example of the transport mechanism. [Figure 6] FIG. 11 is a diagram showing a modified example of the transport mechanism (part 3). [Figure 7] FIG. [Figure 8] FIG. 2 is a diagram showing the configuration of an electrode body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof will not be repeated.

[0015] In the embodiments described below, when referring to the number, amount, etc., the scope of the present technology is not necessarily limited to the number, amount, etc., unless otherwise specified. In addition, in the following embodiments, each component is not necessarily essential to the present technology, unless otherwise specified. In addition, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiment.

[0016] In this specification, the words "comprise", "include" and "have" are open-ended, i.e., when a certain configuration is included, other configurations may or may not be included.

[0017] Furthermore, when geometric terms and terms expressing positional and directional relationships, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along" are used in this specification, these terms allow for manufacturing errors and slight variations. When terms expressing relative positional relationships, such as "upper side" and "lower side," are used in this specification, these terms are used to indicate relative positional relationships in one state, and the relative positional relationships can be inverted or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0018] In this specification, the term "battery" is not limited to lithium ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium ion batteries. In this specification, the term "electrode" may collectively refer to positive and negative electrodes. In addition, the term "electrode plate" may collectively refer to positive and negative plates.

[0019] In this specification, a "battery cell" can be mounted in a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric vehicle (BEV), etc. However, the use of the "battery cell" is not limited to being mounted in a vehicle.

[0020] FIG. 1 is a diagram showing a state in which an electrode body 1 is wound using a manufacturing apparatus for a wound type electrode body, and FIG. 2 is a diagram showing the configuration of the manufacturing apparatus for a wound type electrode body.

[0021] As shown in Figures 1 and 2, the manufacturing apparatus for an electrode body in this embodiment is a manufacturing apparatus for a winding-type electrode body 1, and includes a core body 100, a first driving unit 200, a conveying mechanism 300, and a second driving unit 400.

[0022] The core body 100 has a central axis 100A, an outer circumferential surface 100B, and a hole 100C. The first driving unit 200 drives the core body 100 to rotate about the central axis 100A. The first driving unit 200 can move the core body 100 back and forth along the direction of the central axis 100A (the direction of the arrow DR1 in FIG. 1).

[0023] When winding the wound electrode body 1, the core body 100 is rotated while the electrode plates and separators constituting the electrode body 1 are supplied onto the outer peripheral surface 100B of the core body 100. As a result, the electrode plates and separators are wound onto the outer peripheral surface 100B.

[0024] A transport mechanism 300 is provided on the outer peripheral surface 100B. In the example of Fig. 1 and Fig. 2, the transport mechanism 300 is configured with a chain-shaped member (belt-shaped member). However, the transport mechanism 300 may be configured with a belt-shaped member, for example, or a chain-shaped member and a belt-shaped member may be used in combination.

[0025] The transport mechanism 300 is driven by a second drive unit 400. As shown in Fig. 2, the second drive unit 400 includes storage units 410, 420 for the chain-like member that constitutes the transport mechanism 300. The storage units 410, 420 are provided with a drive mechanism (e.g., a motor, not shown) for unwinding and winding the chain-like member. When the transport mechanism 300 is driven in the direction of the arrow DR2 in Fig. 1, one end of the chain-like member is unwound from the storage unit 410, and the other end of the chain-like member is wound up around the storage unit 420.

[0026] The chain-shaped member constituting the transport mechanism 300 extends from the storage section 410 along the direction of the central axis 100A of the core body 100, on the outer peripheral surface 100B of the core body 100, toward the tip (first end) of the core body 100. The transport mechanism 300 folded back at the tip of the core body 100 extends inside the core body 100 toward the base (second end) of the core body 100 along the direction of the central axis 100A of the core body 100. The transport mechanism 300 is drawn out from inside the core body 100 onto the outer peripheral surface 100B through a hole 100C located closer to the base of the core body 100 than the storage section 410. The transport mechanism 300 drawn out onto the outer peripheral surface 100B of the core body 100 reaches the storage section 420.

[0027] The electrode body 1 formed on the outer peripheral surface 100B of the core body 100 is removed from the core body 100 and proceeds to the next process. At this time, the core body 100 is driven in the direction of arrow DR1 (first direction) by the first driving unit 200. The transport mechanism 300 is driven in the direction of arrow DR2 by the second driving unit 400. As a result, the electrode body 1 on the outer peripheral surface 100B is driven in the opposite direction (arrow DR3 direction) to the moving direction of the core body 100 (arrow DR1 direction).

[0028] 2, the second driving unit 400 is provided on the outer periphery of the core body 100. In addition, the second driving unit 400 is located closer to the tip end of the core body 100 than the first driving unit 200.

[0029] Here, the transport mechanism 300 moves the electrode body 1 in the direction of arrow DR3 at a speed that offsets the movement of the core body 100 in the direction of arrow DR1 by the first drive unit 200. Therefore, when the electrode body 1 is removed from the core body 100, the electrode body 1 is not displaced in the stationary coordinate system. In this way, by driving the electrode body 1 in the opposite direction (arrow DR3 direction) to the removal direction (arrow DR1 direction) of the core body 100 at approximately the same speed as the removal speed of the core body 100, the electrode body 1 can be removed from the electrode body 1 without gripping it.

[0030] In a manufacturing apparatus that does not have a transport mechanism 300, it is necessary to grip the electrode body 1 with a chuck or the like when removing the electrode body 1 from the winding core body 100. Gripping the electrode body 1 may cause a winding slippage (a state in which a part of the electrode body 1 is deformed in the winding axis direction) in the electrode body 1 due to sliding resistance generated at the innermost periphery of the electrode body 1. In addition, gripping the electrode body 1 may have some effect on the electrode surface.

[0031] In contrast, in the manufacturing apparatus according to the present embodiment, the electrode body 1 can be moved in the opposite direction (the direction of arrow DR3) at a speed that offsets the movement of the core body 100 in the direction of arrow DR1 by the first drive unit 200, so there is no need to grip the electrode body 1 with a chuck or the like when removing the electrode body 1 wound around the core body 100, and it is possible to reduce winding misalignment and effects on the electrode surface. As a result, the reliability of the electrode body 1 can be improved and a high-quality battery can be obtained.

[0032] Fig. 3 is a diagram showing an example of a core body 100 and a transport mechanism 300 provided on its outer peripheral surface 100B. As shown in Fig. 3, a plurality of transport mechanisms 300 (six in the example of Fig. 3) are provided so as to be arranged at approximately equal intervals in the circumferential direction of the outer peripheral surface 100B of the core body 100.

[0033] 4 to 6 are diagrams showing modified examples of the conveying mechanism 300. As shown in Fig. 4 to 6, the number and arrangement of the conveying mechanisms 300 can be changed as appropriate. In addition, the width of the chain-like or belt-like members constituting the conveying mechanism 300 can also be made wider, for example, as shown in Fig. 4.

[0034] 7 is an exploded perspective view of a battery cell. As shown in FIG. 7, the battery according to this embodiment includes an electrode body 1, a rectangular exterior body 2, and a cover member 3.

[0035] The electrode body 1 has a positive electrode 11 and a negative electrode 12 aligned in the X-axis direction (longitudinal direction). The electrode body 1 has an outer surface 10A (first outer surface) and an outer surface 10B (second outer surface) positioned opposite each other along the Y-axis direction (short-side direction).

[0036] The rectangular exterior body 2 has an opening 21 that opens upward. Inside the rectangular exterior body 2, the electrode assembly 1 and an electrolyte (not shown) are contained.

[0037] The lid member 3 seals the opening 21 of the rectangular exterior body 2. A positive electrode external terminal 31A and a negative electrode external terminal 32A are provided on the upper surface of the lid member 3 with a gap in the X-axis direction. A positive electrode side current collector 31 and a negative electrode side current collector 32 are provided on the lower surface of the lid member 3. The positive electrode side current collector 31 is electrically connected to the positive electrode external terminal 31A. The negative electrode side current collector 32 is electrically connected to the negative electrode external terminal 32A.

[0038] Furthermore, the current collector 31 is connected to the positive electrode 11 of the electrode body 1, and the current collector 32 is connected to the negative electrode 12 of the electrode body 1. This electrically connects the positive electrode 11 and the negative electrode 12 of the electrode body 1 to the positive electrode external terminal 31A and the negative electrode external terminal 32A of the cover member 3.

[0039] Fig. 8 is a diagram showing the configuration of the electrode assembly 1. As shown in Fig. 8, the electrode assembly 1 includes a positive electrode plate 11A constituting the positive electrode 11, a negative electrode plate 12A constituting the negative electrode 12, and separators 13 and .

[0040] The positive electrode plate 11A has a first region 11B in which a positive electrode active material mixture layer (first active material layer) containing a positive electrode active material (such as lithium nickel cobalt manganese composite oxide), a binder (polyvinylidene fluoride (PVdF)), and a conductive material (such as a carbon material) is formed on both sides of a positive electrode core (first electrode core) made of aluminum foil, a second region 11C in which no active material layer is formed and the positive electrode core is exposed, and a boundary 11D between the first region 11B and the second region 11C. A protective layer (not shown) containing alumina particles, a binder, and a conductive material may be provided in a part of the second region 11C (a part adjacent to the first region 11B).

[0041] The negative electrode plate 12A has a first region 12B in which a negative electrode active material layer (second active material layer) is formed on both sides of a negative electrode core (second electrode core) made of copper foil, a second region 12C in which no active material layer is formed and the negative electrode core is exposed, and a boundary 12D between the first region 12B and the second region 12C.

[0042] The positive electrode plate 11A and the negative electrode plate 12A are wound around the X-axis (winding axis) using the manufacturing apparatus described above. The positive electrode plate 11A and the negative electrode plate 12A are stacked with separators 13 and 14 interposed therebetween. The positive electrode plate 11A and the negative electrode plate 12A removed from the winding core body 100 are formed into a flat shape. This forms an electrode body 1 having a positive electrode 11 located at one end side along the X-axis direction and a negative electrode 12 located at the other end side.

[0043] Next, the electrode body 1 and the current collectors 31, 32 are electrically connected. Thereafter, the electrode body 1 and the current collectors 31, 32 are housed in the rectangular exterior body 2, and the rectangular exterior body 2 is sealed with the lid member 3. Then, an electrolyte is poured into the rectangular exterior body 2, and an airtightness test and the like are performed to complete the battery cell. Note that the batteries to which the present technology can be applied are not limited to rectangular batteries, and may be, for example, cylindrical batteries.

[0044] In this embodiment, the size or number of turns of the electrode body 1 is not particularly limited, but the reliability of the electrode body 1 can be improved more effectively in an electrode body 1 with a large number of turns and a wide width. For example, in an electrode body with a width dimension in the X-axis direction of about 120 mm, when the positive electrode plate 11A and the negative electrode plate 12A or the separators 13 and 14 are wound only about 40 turns, compared with when they are wound only about 60 turns, it is considered that the sliding resistance of the innermost periphery of the electrode body 1 is larger when wound only about 60 turns. Therefore, by using the manufacturing device according to this embodiment, it is possible to effectively suppress the winding slippage and the influence on the electrode surface. Similarly, even if the number of turns is the same, the sliding resistance is larger in a larger electrode body 1, so that by using the manufacturing device according to this embodiment, it is possible to effectively suppress the winding slippage and the influence on the electrode surface.

[0045] Although the embodiment of the present technology has been described above, the embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0046] 1 electrode body, 2 rectangular exterior body, 3 cover member, 21 opening, 10A outer surface, 10B outer surface, 11 positive electrode, 11A positive electrode plate, 11B first region, 11C second region, 11D boundary, 12 negative electrode, 12A negative electrode plate, 12B first region, 12C second region, 12D boundary, 13, 14 separator, 31 current collector, 31A positive electrode external terminal, 32 current collector, 32A negative electrode external terminal, 100 core body, 100A central axis, 100B outer peripheral surface, 100C hole portion, 200 first drive portion, 300 conveying mechanism, 400 second drive portion, 410, 420 storage portion.

Claims

1. A manufacturing apparatus for a wound electrode body, comprising: A core body having an outer circumferential surface and extending in a first direction; a first drive unit that drives and rotates the core body about an axis in the first direction when the wound electrode body is wound, and that moves the core body along the first direction when the wound electrode body is removed; a conveying mechanism provided on the outer circumferential surface of the core body and capable of moving the wound electrode body wound on the outer circumferential surface in a direction opposite to the first direction; a second drive unit that drives the transport mechanism, the transport mechanism moves the wound electrode body in a direction opposite to the first direction at a speed that offsets the movement of the core body in the first direction by the first drive unit, The second drive unit that drives the transport mechanism is located closer to the tip end of the core body than the first drive unit.

2. The manufacturing apparatus for a wound electrode body according to claim 1 , wherein the transport mechanism includes a chain-like member provided on the outer circumferential surface of the core body.

3. The manufacturing apparatus for a wound type electrode body according to claim 1 , wherein the transport mechanism includes a belt-like member provided on the outer circumferential surface of the core body.

4. The manufacturing apparatus for a wound type electrode body according to claim 1 , wherein a plurality of the transport mechanisms are provided so as to be aligned in a circumferential direction of the outer circumferential surface of the core body.

5. A step of manufacturing the wound electrode body using the manufacturing apparatus for the wound electrode body according to any one of claims 1 to 3; a step of electrically connecting an electrode terminal and the wound electrode body; A step of housing the wound electrode body in an outer casing; and sealing the exterior body in which the wound electrode body is housed.

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