JP2009181812A - Wound battery, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a wound battery (typically, a secondary battery such as a lithium-ion battery) with superior productivity, equipped with a current collection tab of corrugated sheet type in which an electrode body and the current collection tab are surely joined. <P>SOLUTION: The method includes a work in which the electrode body sheet is wound, and a work in which a folded parts formed by folding back a part of the current collecting tab sheet 10 at a prescribed spacing against the electrode body 21 on the way of being wound by the winding work are arranged on outer peripheral faces 24 of the lamination layer end part of the electrode body 21 on the way of being wound. Here, through the winding work and the folded part arranging work, a plurality of folded parts arranged on the outer peripheral faces 24 of the lamination layer end parts at the prescribed spacing are respectively arranged between the different gaps between the layers of the lamination layer end parts, and the plurality of folding parts are aligned in the diameter direction of the wound electrode body. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a battery and a technique for manufacturing the battery. Specifically, the present invention relates to a wound battery in which a corrugated current collecting tab is formed on a wound electrode body having a spiral structure, and a manufacturing technique of the battery.

  As one form of the battery, a battery including an electrode body (wound electrode body) having a spiral structure can be given. By making the electrode body have a spiral structure, the reaction area of the positive and negative electrodes per predetermined volume can be increased, thereby increasing the energy density and enabling high output. A battery provided with such a wound electrode body (hereinafter referred to as a “turned battery”), in particular, a wound lithium ion battery, is a power source for mounting on a vehicle or a personal computer and a portable seat terminal as a power source for obtaining a high output. The importance as a power source is increasing.

  By the way, there is a tab type current collection as one of current collection methods for this type of battery (winding type battery). That is, in this type of battery, the side edge along the longitudinal direction of the electrode body composed of a long sheet-shaped current collector is defined as an active material layer non-formed portion (that is, a portion where the current collector is exposed). The current collecting tab is connected to the laminated end portion formed by laminating the side edge end portion (portion where the active material layer is not formed) in the radial direction by winding. In such a configuration, current can be taken out from the electrode body through the current collecting tab, so that current collecting resistance can be reduced and charge / discharge efficiency can be improved.

As one form of such a current collecting tab, there is proposed a current collecting tab formed by folding a long sheet-like current collector made of a metal foil into a folding screen (in other words, corrugated plate). . For example, in Patent Document 1, a strip-like current collecting tab member is bent in a folding screen at the edge (that is, the laminated end portion) of a positive or negative electrode core (current collector) constituting an electrode body. A technique for engaging a current collecting tab is disclosed. Further, Patent Document 2 can be cited as another conventional technique related to this type of current collecting tab.
JP 2001-155711 A JP 2000-323120 A

  However, the above-described prior art has room for further improvement from the viewpoint of production efficiency. That is, in the technique disclosed in Patent Document 1, the construction of the current collector tab (processing to fold the current collector tab into a folding screen) and the construction of the wound electrode body (winding of the electrode body sheet) are performed separately, Thereafter, a folding screen-like current collecting tab is attached to the end face of the electrode body. From the viewpoint of production efficiency, it is preferable to simultaneously construct the current collecting tab and the wound electrode body.

  Further, in the technique of Patent Document 1, when a folding screen-like current collecting tab is pushed into the end face of the electrode body, each core (current collector) edge is placed between the opposing bent surfaces of the current collecting tab. It is necessary to pinch them one by one, but the arrangement pitch of the core body edges (that is, the interlayer gap at the end of the laminated layer) is so narrow that misalignment is likely to occur, and the electrode body and the current collecting tab are correctly aligned. There is a risk of not being joined. If the electrode body and the current collecting tab are not properly joined, it is not preferable because a sufficient electrical connection cannot be secured and the current collecting resistance may increase (or a connection failure may occur).

  The present invention has been made in view of the above points, and its main object is to provide a winding having a corrugated current collecting tab with good productivity while reliably joining the electrode body and the current collecting tab. It is to provide a method of manufacturing a type battery (typically a secondary battery such as a lithium ion battery). Moreover, it is providing the winding type battery with a current collection tab manufactured by such a manufacturing method (typically secondary batteries, such as a lithium ion battery).

  The battery manufacturing method provided by the present invention includes a positive electrode and a negative electrode body sheet in which a positive electrode and a negative electrode active material layer are formed on the surfaces of a long sheet-shaped positive electrode and negative electrode current collector, respectively. A wound electrode body formed by winding and a current collecting tab sheet connected to the positive electrode side or the negative electrode side of the wound electrode body, and a plurality of folded portions formed by alternately folding the sheet Current collectors that are disposed in the interlaminar gaps of the stacked end portions formed of the electrode active material layer non-forming portions of the current collector that are stacked in the radial direction of the wound electrode body by the winding. A tab sheet and a positive or negative electrode terminal for external connection electrically connected to the current collecting tab sheet (that is, a positive electrode terminal or a negative electrode terminal for electrical connection with an external device; the same applies hereinafter). Is a method of manufacturing a battery comprising:

  The manufacturing method includes the operation of winding the electrode body sheet and the folding formed by folding a part of the current collecting tab sheet at a predetermined interval with respect to the electrode body wound by the winding operation. And an operation of arranging the portion on the outer peripheral surface of the laminated end portion of the electrode body in the course of being wound. In the winding operation and the folding portion arranging operation, each of the plurality of folding portions arranged on the outer peripheral surface of the laminated end portion at the predetermined interval is arranged in a different interlayer gap of the laminated end portion. And it is performed so that this some folding part may be arranged in the radial direction of a winding electrode body.

  According to the manufacturing method having the above-described configuration, the folding portions that are part of the current collecting tabs are sequentially disposed in the interlayer gaps at the stacked end portions (active material layer non-formed portions) of the electrode bodies stacked by winding. The wound electrode body can be constructed as it is. That is, in the manufacturing method of the present invention, the winding operation (process) of the wound electrode body and the folding portion arranging operation (process) of the current collecting tab can be performed simultaneously. Therefore, a wound electrode body can be produced with good productivity (that is, efficiently and quickly).

  In addition, by folding and arranging the sheet-like current collecting tab, the folded portion can be securely placed (inserted) in the gap regardless of the width and size of the interlayer gap at the laminated end (electrode active material layer non-formed portion). It is possible to prevent positional deviation between the electrode body and the current collecting tab. As a result, it is possible to prevent a product failure (for example, a connection failure due to a positional deviation between the wound electrode body and the current collecting tab).

  Moreover, according to this manufacturing method, it arranges so that the several folding part formed by folding a current collection tab in a waveform may align with the radial direction (stacking direction) of the said lamination | stacking edge part of an electrode body. By arranging a plurality of folding portions in this way, gas generated from the inside of the wound electrode body can be released from the end face of the wound electrode body that is not covered by the current collecting tab. Therefore, according to the said method, the battery provided with the winding electrode body which can ensure favorable degassing property can be provided. Moreover, there exists an advantage that the joining operation | work of a folding part and a lamination | stacking edge part can be performed easily by aligning a some folding part in a row.

  In a preferable aspect of the manufacturing method disclosed herein, the winding operation and the folding portion arranging operation are performed so that one folding portion is arranged for each interlayer gap at the stacked end portion. By arranging and arranging the folding parts in this way, the contact area between the wound electrode body and the current collecting tab can be increased. As a result, a battery with higher current collection efficiency (for example, a secondary battery such as a lithium ion battery) can be manufactured.

  In another preferable aspect of the manufacturing method disclosed herein, after the winding operation and the folding portion placement operation are performed, the electrode is inserted into the stacked end portion of the wound electrode body and the interlayer gap between the stacked end portions. A current collecting tab joining operation for joining together a plurality of folded portions is performed.

  According to the manufacturing method having such a configuration, the electrode body and each foldable portion can be joined together at one time, which is preferable from the viewpoint of improving productivity and reducing energy costs (manufacturing costs). In addition, since the interlayer gap at the laminated end is closed by the thickness of the folded portion inserted into the gap, the rigidity of the laminated end (that is, the portion made of the exposed sheet-like current collector) is improved. Can do. As a result, the joining process described above can be performed without forcibly bending the laminated end, and the current collector itself constituting the laminated end (that is, the portion where the electrode active material layer is not formed) is damaged (foil-like). In the case of the current collector, the foil can be prevented from being broken).

  In a preferable aspect of the manufacturing method disclosed herein, part of the current collecting tab and the electrode terminal are directly joined in the joining operation. According to this method, the electrode body, the current collecting tab, and the external connection electrode terminal (positive electrode terminal or negative electrode terminal) can be joined together at a time, which is preferable from the viewpoint of productivity, energy cost, and the like. In addition, since the folded portion of the current collecting tab is directly attached to the electrode terminal, the current collecting tab is not interposed without an extra connection member (for example, a lead member connecting the current collecting tab and the external connection electrode terminal). In addition, the current can be directly taken out of the battery via the electrode terminal, and a battery having a simple current collecting structure can be provided with good productivity.

  In a preferred embodiment of the manufacturing method disclosed herein, the electrode terminal has a flat surface. And the folding part of the said current collection tab is joined to this flat surface. According to the manufacturing method of such a configuration, since the folded portion of the current collecting tab can be bonded to the flat surface of the external connection electrode terminal (positive electrode terminal or negative electrode terminal), the bonding operation of both is possible. It becomes easy and the joint strength in a current collection joining surface can be improved.

  In a preferred aspect of the manufacturing method disclosed herein, the electrode terminal is an axial core disposed at the winding center of the electrode body. According to the manufacturing method of such a configuration, the folding portion arranged on the innermost winding side of the plurality of folding portions of the current collecting tab and the electrode terminal can be directly joined, so that the joining work Thus, it is possible to manufacture a battery (for example, a cylindrical wound battery) having improved current collecting joint rigidity.

  The present invention also provides a battery that can be suitably manufactured by the manufacturing method disclosed herein. One preferred embodiment of the battery provided by the present invention is a positive electrode and a negative electrode in which a positive electrode and a negative electrode active material layer are formed on the surfaces of a long sheet-shaped positive electrode and negative electrode current collector, respectively. A wound electrode body formed by winding a body sheet, and a plurality of folded tab sheets formed by alternately folding the sheet, the current collecting tab sheet being connected to the positive electrode side or the negative electrode side of the wound electrode body And the folded portions are arranged in the interlaminar gaps at the end portions of the current collector where the electrode active material layer is not formed by laminating in the radial direction of the wound electrode body by the winding. A battery comprising a current collecting tab sheet and an electrode terminal for external connection on the positive electrode side or the negative electrode side electrically connected to the current collecting tab sheet. And a part of said current collection tab sheet | seat and the said electrode terminal are joined directly, It is characterized by the above-mentioned.

  In the wound type battery having such a configuration (typically a secondary battery such as a lithium ion battery), the folded portion of the current collecting tab sheet is directly joined (directly attached) to the electrode terminal, which is unnecessary. The current can be directly taken out via the current collecting tab and the electrode terminal without interposing a connecting member (for example, a lead member connecting the current collecting tab and the external connection electrode terminal). Further, the current collecting space inside the battery is reduced, and the current collecting resistance can be reduced, thereby improving the battery output. Further, there is no possibility that the connection member (for example, the lead member) is damaged by vibration or the like.

  Preferably, the electrode terminal has a flat surface, and the folded portion of the current collecting tab is welded to the flat surface in surface contact. By joining the folded portion of the current collecting tab in surface contact with the flat surface of the electrode terminal, the joining strength at the current collecting joint surface can be improved.

  In a further preferred aspect of the battery provided by the present invention, the electrode terminal is an axial core disposed at the winding center of the electrode body. According to this configuration, the rigidity of the current collecting joint surface between the current collecting tab sheet and the electrode terminal is improved.

  Moreover, this invention provides the manufacturing apparatus for implementing suitably the manufacturing method disclosed here. The production apparatus provided by the present invention includes a positive electrode and a negative electrode body sheet in which positive electrode and negative electrode active material layers are respectively formed on the surfaces of a long sheet-like positive electrode and negative electrode current collector. A wound electrode body that is rotated, and a current collecting tab sheet that is connected to a positive electrode side or a negative electrode side of the wound electrode body, and includes a plurality of folded portions formed by alternately folding the sheet. A current collecting tab sheet disposed in an interlaminar gap at the end portion of the current collector where the electrode active material layer is not formed on the current collector, wherein the folded portions are laminated in the radial direction of the wound electrode body by the winding; The device is used for manufacturing a battery including a positive electrode side or a negative electrode side external connection electrode terminal electrically connected to the current collecting tab sheet.

  And the apparatus which concerns on this invention winds the said electrode body sheet | seat around the axial center used as the winding center, and the electrode body wound by the said winding means at a predetermined space | interval. And a current collecting tab supply means for arranging the folded portion formed by folding a part of the current collecting tab sheet on the outer peripheral surface of the laminated end portion of the electrode body being wound.

  The winding means and the current collecting tab supply means are arranged such that each of the plurality of folding portions arranged on the outer peripheral surface of the stacked end portion at the predetermined interval is disposed in a different interlayer gap of the stacked end portion. And it is comprised so that it may mutually operate | move so that these folding parts may be arranged in the radial direction of a wound electrode body.

  With the apparatus having such a configuration, the method of manufacturing a wound battery having a current collecting tab disclosed herein can be suitably implemented.

  Preferably, the current collecting tab supply means folds a part of the current collecting tab sheet to form the folded portion, and the electrode body in which the formed folded portion is wound by the winding means. A movable extrusion bar is provided on the outer peripheral surface. By providing such a movable push-out bar (see the embodiment described later), a predetermined folded portion formed smoothly by folding a part of the current collecting tab sheet on the outer peripheral surface of the laminated end portion of the electrode body being wound is predetermined. Can be arranged at intervals of.

  Embodiments according to the present invention will be described below with reference to the drawings. In the following drawings, members / parts having the same action are described with the same reference numerals. The present invention is not limited to the following embodiments. Note that the dimensional relationships (length, width, thickness, etc.) in each drawing do not reflect the actual dimensional relationships, and in order to simplify the drawings, a wound electrode body having fewer turns than the actual number is used. Illustrated. Matters other than the matters specifically mentioned in the present specification and necessary for the implementation of the present invention (for example, a method for producing an electrode active material, a general technique relating to construction of a battery, etc.) It can be grasped as a design matter of those skilled in the art based on the technology. The present invention can be carried out based on the contents disclosed in this specification and common technical knowledge in the field. In the following drawings, the positive electrode side is mainly described as an example, but the embodiment can be applied to both positive and negative, and can be similarly applied to the negative electrode side.

  With reference to FIG. 1, the structure of the electrode body sheet | seat 20 which has the shape which can be wound used for the wound electrode body 60 which concerns on this embodiment is demonstrated. FIG. 1 is a perspective view schematically showing the configuration of the wound electrode body 60 of the present embodiment. FIG. 2 is an essential part cross-sectional view showing an enlarged main part cross section of the wound electrode body 60.

  As shown in FIG. 1, the wound electrode body 60 according to the present embodiment is formed by winding an electrode body sheet 20. The electrode body sheet 20 has a long (strip-shaped) sheet structure in a stage before assembling the wound electrode body 60. The electrode sheet 20 is a long sheet-like positive electrode and negative electrode current collector (hereinafter referred to as “positive electrode sheet 30” and “negative electrode sheet 40”, respectively) in the same manner as a typical wound electrode body. It is formed by laminating together with two sheet-like separators (hereinafter referred to as “separator sheet 22”).

  The positive electrode sheet 30 is formed by attaching a positive electrode active material layer 32 for a battery to the surface of a long sheet-like positive electrode current collector 34. However, the positive electrode active material layer 32 is not attached to one side edge (upper side edge portion in the figure) along the edge in the width direction of the electrode body sheet 20, and the positive electrode current collector 34 has a certain width (for example, 10 mm), a positive electrode active material layer non-formation portion 36 is formed.

  On the other hand, similarly to the positive electrode sheet 30, the negative electrode sheet 40 is formed by attaching a negative electrode active material layer 42 for a battery to the surface of a long sheet-like negative electrode current collector 44. However, the negative electrode active material layer 42 is not attached to one side edge (the lower side edge portion in the figure) along the edge in the width direction of the electrode body sheet 20, and the negative electrode current collector 44 has a certain width ( For example, the negative electrode active material layer non-forming portion 46 exposed at 10 mm) is formed.

  In addition, the material itself which comprises the positive electrode sheet 30 and the negative electrode sheet 40 may be the same as that of the electrode body of the conventional lithium ion battery, and there is no restriction | limiting in particular. For example, an aluminum foil (this embodiment) or other metal foil suitable for the positive electrode is preferably used for the positive electrode current collector 34. For the negative electrode current collector 44, a copper foil (this embodiment) or other metal foil suitable for the negative electrode is preferably used.

  When constructing the wound electrode body 60, an electrode body sheet 20 in which the positive electrode sheet 30 and the negative electrode sheet 40 are laminated via the separator sheet 22 is prepared. At this time, the separator sheet 22 is such that the positive electrode active material layer non-formed portion (exposed portion of the positive electrode current collector 34) 36 of the positive electrode sheet 30 protrudes outward (that is, the positive electrode active material layer 32 and the separator sheet 22 face each other). To be superimposed).

  The negative electrode sheet 40 is also laminated in the same manner as the positive electrode sheet 30 so that the negative electrode active material layer non-formed part (exposed part of the negative electrode current collector 44) 46 protrudes outward from the separator sheet 22 (that is, the negative electrode active material layer 42 and The separator sheet 22 is overlapped with each other. A wound electrode body 60 is obtained by winding the electrode body sheet 20 (for example, about 50 turns).

  A wound core portion 62 (that is, the positive electrode active material layer 32 of the positive electrode sheet 30, the negative electrode active material layer 42 of the negative electrode sheet 40, and the separator sheet 22 is densely arranged in the central portion of the wound electrode body 60 in the winding axis direction. Laminated portions) are formed. Further, a positive electrode current collector in which a positive electrode active material layer non-formation portion 36 (exposed portion of the positive electrode current collector 34) is wound and laminated at one end portion in the winding axis direction of the wound electrode body 60. A laminated portion 63 (a positive electrode current collector laminated portion having a configuration in which foil-like positive electrode current collectors are laminated) is formed. A negative electrode current collector in which a negative electrode active material layer non-formation portion 46 (exposed portion of the negative electrode current collector 44) is wound and laminated at the other end in the winding axis direction of the wound electrode body 60. A laminated portion 64 (a negative electrode current collector laminated portion having a configuration in which foil-shaped negative electrode current collectors are laminated) is formed.

  The positive electrode side current collecting tab sheet 10 is connected to the positive electrode side of the wound electrode body 60. The material constituting the positive electrode side current collecting tab sheet 10 is preferably a material having good conductivity and capable of being appropriately joined to the positive electrode current collector 34, and here is a long sheet-like aluminum foil. Moreover, in this embodiment, the negative electrode side current collection tab sheet 18 is connected to the negative electrode side of the wound electrode body 60 (see FIG. 6). The material constituting the negative electrode side current collecting tab sheet 18 is preferably a material having good conductivity and capable of being appropriately joined to the negative electrode current collector 44. For example, a long sheet-like copper foil is preferably used. it can.

  As shown in FIG. 2, the positive electrode side current collecting tab sheet 10 is a wave-shaped current collecting tab sheet 10 including a plurality of folding portions 14 formed by alternately folding the sheets. The plurality of folded portions 14 are formed of a positive electrode active material layer non-forming portion 36 of the positive electrode current collector 34 that is stacked in the radial direction (left and right direction in FIG. 2) of the wound electrode body 60 by the winding. They are arranged (inserted) in the interlayer gaps at the ends and joined. In this embodiment, the plurality of folding portions 14 are arranged one by one for each inter-layer gap at the end of the stack composed of the positive electrode active material layer non-forming portions 36. Thus, by arranging the folded portion 14 of the current collecting tab sheet 10 in the interlayer gap at the laminated end, the contact area between the current collecting tab sheet 10 and the positive electrode sheet 30 can be increased, and high current collecting efficiency is achieved. can do.

  The current collecting tab sheets 10 and 18 are electrically connected to the external connection electrode terminals 80 and 86 on the positive electrode side or the negative electrode side, respectively (see FIGS. 2 and 6). In this embodiment, the external connection positive terminals 80 and 86 are disposed inside the innermost winding periphery of the wound electrode body 60 and are joined to the current collecting tab sheets 10 and 18, respectively.

  Next, a manufacturing apparatus 70 used for manufacturing a battery including the wound electrode body 60 and the current collecting tab sheet 10 described above will be described with reference to FIGS. 3A to 3C. FIG. 3A is a schematic top view schematically showing the configuration of the manufacturing apparatus 70, and FIGS. 3B and 3C are schematic cross-sectional views for explaining the operation of the manufacturing apparatus 70. Hereinafter, although the description will be mainly given of the positive electrode side of the wound electrode body, the manufacturing apparatus according to the present embodiment can be similarly applied to the negative electrode side as well.

  The manufacturing apparatus 70 according to the present embodiment includes a winding means that winds the electrode body sheet 20 around an axis 72 that is a winding center, and an electrode body 21 that is being wound (hereinafter referred to as “winding halfway”). Current collecting tab supply means 74 that arranges the folding portion 14 on the outer peripheral surface 24 of the laminated end portion in the body 21).

  The shaft core 72 is configured to wind up the drawn electrode body sheet 20 and to be detached from the wound electrode body 60 after the winding is completed. In this embodiment, the shaft core 72 is connected and fixed to a shaft core support portion (not shown) as winding means. The shaft core support portion is connected to a drive source (for example, a motor) (not shown) that constitutes the winding means, and supports the shaft core 72 so as to be rotatable in one direction. Then, the shaft core support portion is configured to wind the conveyed electrode body sheet 20 around the shaft core 72 serving as a winding center by rotating the shaft core 72 in one direction.

  Current collecting tab supply means 74 is attached to the shaft core 72. The current collecting tab supply means 74 is formed by folding a part of the current collecting tab sheet 10 at a predetermined interval with respect to the electrode body 20 wound by the winding means (that is, the rotating shaft core 72). 14 is arranged on the outer peripheral surface 24 (on the surface of the positive electrode active material layer non-forming portion 36 located on the outermost periphery of the stack) of the electrode body (winding body) 21 in the process of being wound. It is configured. The winding means and the current collecting tab supply means 74 are arranged such that each of the plurality of folding portions 14 arranged on the outer peripheral surface 24 of the laminated end portion at a predetermined interval is arranged in a different interlayer gap at the laminated end portion. The plurality of folding parts 14 are operated in conjunction with each other so that the plurality of folding parts 14 are arranged in the radial direction of the rotating electrode body 60.

  In this embodiment, as shown in FIG. 3B, the current collecting tab supply means 74 is connected and fixed to the shaft core 72 via the connecting collar portion 73, and is configured to rotate in one direction together with the shaft core 72. Has been. Moreover, the current collection tab supply means 74 is provided with the movable extrusion bar 76 which folds a part of current collection tab sheet | seat 10 and forms the folding part 14, as shown to FIG. 3C. The movable push bar 76 is arranged on the outer peripheral surface 24 of the winding body 21 in which the formed folding portion 14 is wound by the winding means.

  Specifically, the movable push bar 76 is pushed out immediately after the electrode body 21 is wound and laminated while rotating together with the shaft core 72, and the folding portion 14 is disposed on the outer peripheral surface 24 thereof. Further, the movable push bar 76 is pulled back before the electrode body 21 is further wound and laminated. Then, by repeating the push-out and pull-back of the movable push bar 76 with appropriate rotation timing while rotating together with the shaft core 72, each of the plurality of folding portions 14 can be arranged in different interlayer gaps at the stacking end portions. .

  In this embodiment, the movable push bar 76 is housed in the guide rail 75 together with the current collecting tab sheet 10 as shown in FIG. 3B. The guide rail 75 is connected to a drive mechanism (for example, a motor) (not shown), and supports the movable push bar 76 so that it can selectively move in a predetermined direction (the left-right direction in the figure). By using the guide rail 75 in this way, each of the plurality of foldable portions 14 can be accurately arranged in the interlayer gaps at different end portions of the stack.

  In this embodiment, the current collecting tab supply means 74 includes a position adjusting mechanism 79. The position adjusting mechanism 79 is configured to adjust the position of the current collecting tab supply means 74 in accordance with the size of the winding body 21 being wound by the winding means. In this embodiment, the position adjustment mechanism 79 includes a displacement sensor (for example, a laser displacement meter) that detects the size of the winding body 21 and a drive mechanism that moves the current collecting tab supply means 74 in the stacking direction (radial direction). (Not shown). Then, the driving mechanism is configured such that the folding portion 14 formed by the movable push-out bar 76 is wound based on the size of the winding body 21 detected by the displacement sensor (for example, the position of the outer peripheral surface 24 may be used). The height position of the current collecting tab supply means 74 (particularly the movable push bar 76) is adjusted so as to be disposed on the outer peripheral surface 24 of the halfway member 21.

  Further, in this embodiment, the current collecting tab supply means 74 includes a current collecting tab retainer 78. As shown in FIG. 3C, the current collecting tab retainer 78 is configured to press the folding portion 14 disposed on the outer peripheral surface 24 of the winding body 21 toward the shaft core 72. Thereby, a crease | fold can be given to the folding part 14 folded alternately. In addition, the current collecting tab holder 78 presses the folding portion 14 disposed on the outer peripheral surface 24 of the winding body 21 toward the shaft core 72 so that the folding portion 14 is wound during winding. 21 also has a role of fixing so as not to be peeled off from the outer peripheral surface 24. In the illustrated example, the current collecting tab retainer 78 is disposed between the guide rail 75 and the electrode body sheet 20 and is swingably attached to the current collecting tab supply means 74 via a spring mechanism 77. . The folding portion 14 is pressed toward the shaft core 72 by the elastic force of the spring mechanism 77.

  Next, with reference to FIGS. 4A to 4C and FIGS. 5A to 5C, the manufacturing process of the battery including the wound electrode body 60 and the current collecting tab sheet 10 and the operation of the manufacturing apparatus 70 will be described. In each figure, the corrugated current collecting tab 10 is formed on one side (upper side in the figure) of the laminated end part laminated in the radial direction of the wound electrode body, but the opposite side (figure of FIG. In this case, the corrugated current collecting tab 10 can be formed by a similar process and apparatus at the lower laminated end.

  First, as shown in FIG. 4A, an operation of winding the electrode body sheet is performed (winding operation). This winding operation is performed by winding the electrode body sheet 20 around the shaft core 72 serving as a winding center by a winding means (not shown). In this embodiment, each constituent material (positive and negative electrode sheets and two separator sheets) constituting the electrode body sheet 20 is pulled out from the roll state and fixed to the shaft core 72, and the shaft core 72 is attached while applying a predetermined tension. The electrode body sheet 20 is wound around the shaft core 72 by rotating in one direction.

  Next, as shown in FIG. 4B, a folded portion formed by folding a part of the current collecting tab sheet 10 at a predetermined interval with respect to the electrode body (winding body) 21 wound by the winding operation. 14 is performed on the outer peripheral surface 24 of the laminated end portion of the electrode body (winding body) 21 being wound (folding portion placement work). This arrangement work is performed by pushing the movable push bar 76 from the guide rail 75 in a predetermined direction (left direction in the figure).

  Next, as shown in FIG. 4C, the movable push bar 76 is pulled back and accommodated in the guide rail 75. At this time, the current collecting tab retainer 78 moves downward and presses the folding portion 14 in the stacking direction (toward the axis 72) by the elastic force of the spring mechanism 77. Thereby, a fold is given to the folding part 14 arrange | positioned by folding.

  Next, as shown in FIG. 5A, an operation of further winding the electrode body sheet 20 is performed (winding operation). By this further winding operation, the electrode body sheet (electrode active material layer non-forming portion 36) is wound on the folding portion 14 disposed on the outer peripheral surface 24 of the winding body 21. In this manner, the folded portion 14 of the current collecting tab sheet 10 can be disposed (inserted as a result) in the interlayer gap at the laminated end portion. Further, this winding operation is executed while pressing the folding portion 14 with the current collecting tab presser 78. Accordingly, it is possible to avoid a situation in which the folding unit 14 is peeled off from the outer peripheral surface 24 of the winding body 21 during winding.

  Next, as shown in FIG. 5B, the position of the current collecting tab supply means 74 is adjusted (moved upward in the figure) by the position adjusting mechanism 79, and the folding portion arranging work is performed again by the current collecting tab supply means 74. At this time, the current collecting tab supply means 74 performs the above arrangement operation while rotating together with the shaft core 72. Therefore, each of the folding portions 14 arranged in different interlayer gaps at the stacking end portions is arranged around the wound electrode body. It will be arranged at the same position in the direction. Accordingly, each of the plurality of folding portions 14 can be arranged in a line in the stacking direction of the winding body 21 (the radial direction of the wound electrode body 60).

  Then, while the winding means and the current collecting tab supply means 74 are operated in association with each other, by repeating the winding work and the folding portion arranging work, as shown in FIG. Each of the tatami parts 14 is arranged in different interlayer gaps at the stacked end parts and arranged in the radial direction of the wound electrode body 60. Thereafter, the electrode body sheet 20 is cut at the end position so as to have a predetermined length at the end of winding, and the winding end portion cut at the end position is wound up. In this way, it is possible to construct the wound electrode body 60 in which the plurality of folded portions 14 are respectively arranged in the interlayer gaps at the end portions of the stacked layers composed of the electrode active material layer non-formed portions 36.

  According to the manufacturing method having the above-described configuration, the folding portions 14 that are part of the current collecting tabs are sequentially placed in the interlayer gaps of the stacked end portions (active material layer non-formed portions 36) of the electrode bodies 60 stacked by winding. The winding electrode body 60 can be constructed as it is while being arranged. That is, in the manufacturing method of this embodiment, the winding operation (process) of the wound electrode body 60 and the folding portion arrangement operation (process) of the current collecting tab 10 can be performed simultaneously. Therefore, the wound electrode body 60 can be manufactured with good productivity (that is, efficiently and quickly). Further, by arranging the sheet-like current collecting tab 10 while being folded, the folding portion 14 can be reliably arranged in the gap regardless of the width and size of the interlayer gap at the end of the stack (electrode active material layer non-formed portion). (Insertion), and displacement of the electrode body 60 and the current collecting tab 10 can be prevented. As a result, it is possible to prevent a product failure (for example, a connection failure due to a positional deviation between the wound electrode body and the current collecting tab).

  Furthermore, according to such a manufacturing method, the plurality of folded portions 14 formed by folding the current collecting tab 10 into a waveform are arranged so as to be aligned in the radial direction (stacking direction) of the stacked end portion of the electrode body 60. The By arranging the plurality of folding parts 14 in this way, the gas generated from the inside of the wound electrode body 60 can be released from the end face of the wound electrode body 60 that is not covered by the current collecting tab 10. . Therefore, according to the said method, the battery provided with the wound electrode body 60 which can ensure favorable degassing property can be provided.

  In addition, it is preferable that the said winding operation | work and folding part arrangement | positioning work are performed so that the some folding part 14 may be arrange | positioned one by one for every interlayer gap of a lamination | stacking edge part. By arranging and arranging the plurality of folding parts 14 in this way, the contact area between the wound electrode body 60 and the current collecting tab 10 can be increased. As a result, a battery with higher current collection efficiency (for example, a secondary battery such as a lithium ion battery) can be manufactured.

  Further, after carrying out the winding operation and the folding portion arranging operation, the shaft core 72 is removed from the wound electrode body 60 and inserted into the interlaminar gap between the laminated end portion of the wound electrode body 60 and the laminated end portion. You may perform the operation | work which joins together the some folding part 14 currently collected (current collection tab joining operation | work). This current collecting tab joining can be performed by, for example, ultrasonic welding. Specifically, the laminated end portion formed of the positive electrode active material layer non-forming portion 36 and the folding portions 14 respectively disposed in the interlayer gaps of the laminated end portion are placed between ultrasonic welding apparatuses (not shown). Ultrasonic welding can be performed by applying ultrasonic vibration while pressing between the two. Such ultrasonic welding is preferable from the viewpoint of productivity, energy cost, and the like because welding can be performed by a single welding operation.

  In addition, since the interlayer gap at the laminated end is closed by the thickness of the folded portion inserted into the gap, the rigidity of the laminated end (that is, the portion made of the exposed sheet-like current collector) is improved. Can do. As a result, the joining process described above can be performed without forcibly bending the laminated end, and the current collector itself constituting the laminated end (that is, the portion where the electrode active material layer is not formed) is damaged (foil-like). In the case of the current collector, the foil can be prevented from being broken). In addition, the apparatus used for this ultrasonic welding and welding conditions itself may be the same as that of the case where a current collection tab is ultrasonically bonded to the electrode body sheet | seat of the conventional battery, and it does not restrict | limit in particular.

  An example of the battery 100 including the wound electrode body 60 and the wave-type current collecting tab sheet 10 constructed as described above is shown in FIG. The battery 100 according to the present embodiment includes a wound electrode body 60 constructed by the method described above, corrugated current collecting tab sheets 10 and 18 connected to the positive electrode side and the negative electrode side of the wound electrode body 60, and the corrugated waveform. Positive electrode side and negative electrode side external connection electrode terminals 80, 86 electrically connected to the current collecting tab sheets 10, 18 are provided. In this embodiment, the external connection electrode terminals 80 and 86 are axial cores arranged at the winding center of the wound electrode body 60.

  As shown in FIG. 7, the external connection positive electrode terminal 80 includes a current collecting tab terminal 82 and an external terminal 83 connected to the current collecting tab terminal 82. The external terminal 83 is a cylindrical member made of aluminum and has a substantially circular cross section. The external terminal 83 protrudes from the lid of the battery case 88 through the insulating member 81 and the nut 84. Further, the gap between the external terminal 83 and the battery case lid is sealed by a seal member 89 surrounding the external terminal 83. By using the external terminal 83 having a circular cross section in this way, a seal structure with the seal member 89 can be easily constructed. The current collecting tab terminal 82 is a plate-like member made of aluminum, and is inserted inside the wound innermost periphery of the wound electrode body 60. The current collecting tab terminal 82 has a flat surface 85, and a part of the current collecting tab sheet 10 is directly joined (directly attached) to the flat surface 85. In the illustrated example, the flat surface 85 and the folding portion 14c located on the innermost winding side of the current collecting tab sheet 10 are directly joined.

  According to the said structure, since the folding part 14c of the current collection tab sheet | seat 10 is directly joined (directly attached) to the said electrode terminal 80, an unnecessary connection member (For example, a current collection tab, the electrode terminal for external connection, and so on) Current can be directly taken out via the current collecting tab and the electrode terminal without interposing a lead member or the like connecting the two. Further, the current collecting space inside the battery is reduced, and the current collecting resistance can be reduced, thereby improving the battery output. Further, there is no possibility that the connection member (for example, the lead member) is damaged by vibration or the like. Furthermore, since the folded portion 14c of the current collecting tab sheet 10 is welded in a state of being in surface contact with the flat surface 85 of the electrode terminal 80, the bonding strength at the current collecting bonding surface can be improved.

  In addition, you may perform joining of the flat surface 85 of such an electrode terminal 80, and the folding part 14c of the current collection tab sheet | seat 10 simultaneously with current collection tab joining work. That is, after the winding electrode body 60 is constructed by performing the winding operation and the folding portion arrangement operation, the electrode terminal 80 is arranged instead of the shaft core 72, and the stacked end portions of the winding electrode body 60 and the plurality of end portions are arranged. The folding portion 14 and the electrode terminal 80 may be welded together.

  According to this method, the electrode body 60, the current collecting tab 10, and the external connection electrode terminal 80 can be joined together at a time, which is preferable from the viewpoint of productivity, energy cost, and the like. Further, since the folded portion 14c of the current collecting tab is directly attached to the electrode terminal 80, the current collecting tab is folded without interposing an extra connecting member (for example, a lead member connecting the current collecting tab and the external connecting electrode terminal). A current can be directly taken out of the battery through the electric tab and the electrode terminal, and a battery having a simple current collecting structure can be provided with good productivity.

  Next, with reference to FIG. 8, suitable dimensions and the like of the active material layer non-forming part constituting the corrugated current collecting tab and the current collector laminated part will be described. The thickness size of the current collector tab sheet 10 is T, the inter-layer gap size of the end portion of the current collector that is not formed with the electrode active material layer non-forming portion 36 is H, and the length of the electrode active material layer non-forming portion 36 is L. Yes. The number of wrinkles of the electrode body sheet 20 is n. In this case, it is preferable to appropriately adjust the size of each member so that the conditions of the following two expressions (1) and (2) are satisfied.

Formula (1) T <= H / 2
Formula (2) L> (H-2 × T) × n
By satisfying the condition of the above formula (1), the folded portion 14 that is folded in half can be reasonably and reliably arranged in the interlayer gap at the end portion of the current collector where the electrode active material layer non-forming portion 36 is formed. Can do. In addition, when the wound electrode body 60 and the current collecting tab sheet 10 are joined by satisfying the condition of the above formula (2), each of the plurality of folding portions 14 is disposed in the interlayer gap at the stacked end portion. (Particularly, while avoiding the problem that the folded portion 14d located on the outermost peripheral side is disengaged from the active material layer non-formation portion 36d on the outermost peripheral side), it is possible to gather together. A preferred example of the size of each member is, for example, T = 70 μm, L = 10000 μm, H = 200 μm, and n = 50.

The material and member itself constituting the wound electrode body 60 may be the same as the electrode body of the conventional lithium ion battery, and are not particularly limited. For example, the positive electrode sheet 30 can be formed by applying a positive electrode active material layer 32 for a lithium ion battery on a long positive electrode current collector 34. For the positive electrode current collector 34, an aluminum foil (this embodiment) or other metal foil suitable for the positive electrode is preferably used. As the positive electrode active material, one or more of materials conventionally used in lithium ion batteries can be used without any particular limitation. Preferable examples include LiMn ₂ O ₄ , LiCoO ₂ , LiNiO _{2 and the} like.

  On the other hand, the negative electrode sheet 40 can be formed by applying a negative electrode active material layer 42 for a lithium ion battery on a long negative electrode current collector 44. For the negative electrode current collector 44, a copper foil (this embodiment) or other metal foil suitable for the negative electrode is preferably used. The negative electrode active material 42 can be used without any particular limitation on one or more materials conventionally used in lithium ion batteries. Preferable examples include carbon-based materials such as graphite carbon and amorphous carbon, lithium-containing transition metal oxides and transition metal nitrides.

  Moreover, as a suitable separator sheet 22 used between the positive / negative electrode sheets 30 and 40, what was comprised with the porous polyolefin-type resin is mentioned. When a solid electrolyte or a gel electrolyte is used as the electrolyte, there may be a case where a separator is unnecessary (that is, in this case, the electrolyte itself can function as a separator).

Next, the configuration of the electrolyte housed in the battery case 88 together with the wound electrode body 60 will be described. The electrolyte of this embodiment is a lithium salt such as LiPF _6, for example. In the present embodiment, an appropriate amount (for example, concentration 1M) of a lithium salt such as LiPF ₆ is dissolved in a nonaqueous electrolytic solution such as a mixed solvent of diethyl carbonate and ethylene carbonate (for example, a mass ratio of 1: 1) to prepare an electrolytic solution. Can be used as

  Next, the configuration of the battery case 88 will be described. The battery case 88 of the present embodiment has a shape (cylindrical in the illustrated example) that can accommodate the wound electrode body 60. The material of the battery case 88 is not particularly limited as long as it is the same as that used for a typical battery, but a relatively light material can be used. For example, a metal case whose surface is preferably coated with an insulating resin coating, a polyolefin resin such as polypropylene, and other synthetic resin cases are suitable. Moreover, the shape of the battery case 88 is not limited to a cylindrical shape, and may be a box shape, for example. In the case of using a box-type battery case, a flat-shaped wound electrode body produced by crushing and ablating the wound body from the side surface direction can be preferably used. The battery 100 of the present embodiment is constructed by housing the wound electrode body 60 and the corrugated current collecting tabs 10 and 16 in the battery case 88 and injecting and sealing the electrolyte.

  The battery 100 according to the present embodiment can be suitably used as a power source for a motor (electric motor) mounted on a vehicle such as an automobile as shown in FIG. In other words, the battery 100 according to this embodiment is arranged as a single battery in a predetermined direction, and the single battery is constrained in the arrangement direction to construct the assembled battery 200, and the vehicle 210 ( An automobile, in particular, an automobile equipped with an electric motor such as a hybrid automobile, an electric automobile, and a fuel cell automobile) can be provided.

  As mentioned above, although this invention was demonstrated by suitable embodiment, such description is not a limitation matter and of course various modifications are possible. For example, the configuration of the battery 100 is not particularly limited. A nickel hydride battery, an electric double layer capacitor, etc. are mentioned as a suitable battery structure for implementation of this invention. A battery configuration particularly suitable for the implementation of the present invention is a lithium ion secondary battery. Since the lithium ion secondary battery is a battery that can achieve a high output with a high energy density, it is possible to construct a high-performance power source, particularly a power source for mounting on a vehicle.

The perspective view which shows typically the structure of the electrode body sheet which concerns on this embodiment. The principal part sectional drawing which expands and shows the principal part cross section of the winding electrode body formed by winding the electrode body sheet which concerns on this embodiment. The upper surface schematic diagram which shows typically the manufacturing apparatus which concerns on this embodiment. The cross-sectional schematic diagram for demonstrating operation | movement of the manufacturing apparatus which concerns on this embodiment. The cross-sectional schematic diagram for demonstrating operation | movement of the manufacturing apparatus which concerns on this embodiment. Process drawing for demonstrating the manufacturing process which concerns on this embodiment. Sectional process drawing for demonstrating the manufacturing process which concerns on this embodiment. Sectional process drawing for demonstrating the manufacturing process which concerns on this embodiment. Sectional process drawing for demonstrating the manufacturing process which concerns on this embodiment. Sectional process drawing for demonstrating the manufacturing process which concerns on this embodiment. Sectional process drawing for demonstrating the manufacturing process which concerns on this embodiment. The figure which shows an example of the battery provided with the winding electrode body which concerns on this embodiment. The external appearance perspective view for demonstrating the attachment structure of an electrode terminal. The principal part enlarged view which expanded the periphery of the current collection tab sheet | seat. The side surface schematic diagram of the motor vehicle provided with the battery (assembled battery) which concerns on this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Positive electrode side current collection tab sheet 14, 14c, 14d Folding part 18 Negative electrode side current collection tab sheet 20 Electrode body sheet 22 Separator sheet 30 Positive electrode sheet 32 Positive electrode active material layer 34 Positive electrode current collector 36, 36d Positive electrode active material layer non-formation part 40 Negative electrode sheet 42 Negative electrode active material layer 44 Negative electrode current collector 46 Negative electrode active material layer non-formation part 60 Winding electrode body 62 Winding core part 63 Positive electrode current collector lamination part 70 Manufacturing apparatus 72 Axle core 73 Connecting collar part 74 Collection Electric tab supply means 76 Movable push bar 75 Guide rail 77 Spring mechanism 78 Current collecting tab retainer 79 Position adjustment mechanism 80 Positive terminal (positive terminal for external connection)
81 Seal member 82 Current collecting tab terminal 83 External terminal 84 Nut 85 Flat surface 88 Battery case 100 Battery 200 Assembly battery 210 Vehicle

Claims (10)

A wound electrode body in which a positive electrode and a negative electrode body sheet in which an electrode active material layer for a positive electrode and a negative electrode are formed on the surface of a long sheet-shaped positive electrode and negative electrode current collector, respectively,
The current collecting tab sheet is connected to the positive electrode side or the negative electrode side of the wound electrode body, and includes a plurality of folded portions formed by alternately folding the sheets. Current collecting tab sheets respectively disposed in the interlayer gaps of the laminated end portion composed of the electrode active material layer non-forming portions of the current collector laminated in the radial direction of the wound electrode body;
External connection electrode terminal on the positive electrode side or negative electrode side electrically connected to the current collector tab sheet,
A method for producing a battery comprising:
Winding the electrode body sheet;
The stacked end of the electrode body in the process of winding the folded portion formed by folding a part of the current collecting tab sheet at a predetermined interval with respect to the electrode body wound by the winding operation Working on the outer peripheral surface of the part,
Including
Here, in the winding operation and the folding portion arranging operation, each of the plurality of folding portions arranged on the outer peripheral surface of the laminated end portion at the predetermined interval is arranged in a different interlayer gap of the laminated end portion. And the manufacturing method of a battery characterized by performing so that this some folding part may arrange in the radial direction of a winding electrode body.   2. The manufacturing method according to claim 1, wherein the winding operation and the folding portion arranging operation are performed such that one folding portion is arranged for each interlayer gap of the stacked end portion.   After performing the winding operation and the folding portion placement operation, the stacked end portions of the wound electrode body and the plurality of folded portions inserted in the interlayer gaps of the stacked end portions are joined together. The manufacturing method of Claim 1 or 2 which performs the current collection tab joining operation | work which performs.   The manufacturing method according to claim 3, wherein a part of the current collecting tab and the electrode terminal are directly joined in the joining operation.   The said electrode terminal is a manufacturing method as described in any one of Claims 1-4 which is an axial center arrange | positioned in the winding center of the said electrode body. A wound electrode body in which a positive electrode and a negative electrode body sheet in which an electrode active material layer for a positive electrode and a negative electrode are formed on the surface of a long sheet-shaped positive electrode and negative electrode current collector, respectively,
The current collecting tab sheet is connected to the positive electrode side or the negative electrode side of the wound electrode body, and includes a plurality of folded portions formed by alternately folding the sheets. Current collecting tab sheets respectively disposed in the interlayer gaps of the laminated end portion composed of the electrode active material layer non-forming portions of the current collector laminated in the radial direction of the wound electrode body;
External connection electrode terminal on the positive electrode side or negative electrode side electrically connected to the current collector tab sheet,
A device used to manufacture a battery with
Winding means for winding the electrode body sheet around an axis serving as a winding center;
The stacked end of the electrode body in the process of winding the folded portion formed by folding a part of the current collecting tab sheet at a predetermined interval with respect to the electrode body wound by the winding means Current collecting tab supply means disposed on the outer peripheral surface of the section;
With
Here, the winding means and the current collecting tab supply means are arranged such that each of the plurality of folding portions arranged on the outer peripheral surface of the laminated end portion at the predetermined interval is arranged in a different interlayer gap of the laminated end portion. In addition, the manufacturing apparatus is configured to operate in association with each other so that the plurality of folded portions are arranged in the radial direction of the wound electrode body.   The current collecting tab supply means folds a part of the current collecting tab sheet to form the folded portion, and the formed folded portion is wound on the outer peripheral surface of the electrode body wound by the winding means. The manufacturing apparatus of Claim 6 provided with the movable extrusion bar to arrange | position. A wound electrode body in which a positive electrode and a negative electrode body sheet in which an electrode active material layer for a positive electrode and a negative electrode are formed on the surface of a long sheet-shaped positive electrode and negative electrode current collector, respectively,
The current collector tab sheet is connected to the positive electrode side or the negative electrode side of the wound electrode body, and includes a plurality of folded portions formed by alternately folding the sheets. Current collecting tab sheets respectively disposed in the interlaminar gaps of the laminated end portions composed of the electrode active material layer non-forming portions of the current collector laminated in the radial direction of the wound electrode body;
An electrode terminal for external connection on the positive electrode side or the negative electrode side electrically connected to the current collecting tab sheet,
Here, a part of the current collecting tab sheet and the electrode terminal are directly joined to each other.   The battery according to claim 8, wherein the electrode terminal is an axial core disposed at a winding center of the electrode body.   A vehicle comprising the battery according to claim 8 or 9 or the battery manufactured by the manufacturing method according to any one of claims 1 to 5.

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