JP2010055753A - Method for manufacturing battery with wound electrode body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To push a shaping rod against only a portion requiring shaping of a separator left in a winding core trace space for a sufficient time period. <P>SOLUTION: A method for manufacturing a battery includes steps of: in a forming process displacing a separator left in a winding core trace space 14a of a wound electrode body 14 against the inner peripheral wall of the winding core trace space 14a with the shaping rod, recognizing the position of the separator 13a left in the winding core trace space 14a and the distal end position 13b of the bulge in an image recognition process; obtaining a circumscribed circle CC corresponding to the maximum diameter portion of the winding core trace space 14a and an inscribed circle IC of the maximum diameter formed between the circumscribed circle CC and the separator 13b left in the winding core trace space 14a; inserting a shaping rod 30 into the center of the inscribed circle IC and moving the shape rod toward the center of the circumscribed circle CC; and moving the shape rod linearly or curvilinearly toward the distal end position 13b of the bulge of the separator 13a left in the winding core trace space 14. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a battery including a wound electrode body wound in a spiral shape with a separator interposed between a strip-like positive electrode plate and a negative electrode plate.

  In general, secondary batteries such as non-aqueous electrolyte secondary batteries represented by lithium ion secondary batteries, nickel-cadmium secondary batteries, nickel-hydrogen secondary batteries, etc. are manufactured in rectangular or cylindrical shapes. Has been. Among these, the cylindrical battery is manufactured as follows. First, a separator is interposed between a strip-shaped positive electrode plate and a negative electrode plate, and these are wound in a spiral shape to form a wound electrode body, and a positive electrode current collector and Connect the negative electrode current collector. Next, the wound electrode body is housed in a metal outer can, a current collecting tab extending from one current collector is welded to the lower surface of the sealing body, and a current collecting lead extending from the other current collector Is welded to the inner surface of the bottom of the battery case. Thereafter, an electrolytic solution is injected into the outer can, and a sealing battery is attached to the opening of the battery outer can with an insulating gasket interposed therebetween, thereby sealing the cylindrical battery.

  Among these, the manufacturing process of the conventional cylindrical battery is demonstrated using FIGS. 6A is a perspective view showing a state in which the separator is wound around the core, and FIG. 6B is a view showing a state in which the core is removed. FIG. 7 is a cross-sectional view showing a process of welding one current collecting lead of the wound electrode body to the bottom inner surface of the battery outer can. FIG. 8 is a perspective view showing a separator shaping process. 6 to 8, the same components are given the same reference numerals for explanation.

  The wound electrode body uses, for example, a winding core 51 provided with a longitudinal slit 53 passing through the central portion of the end face 52 as shown in FIG. 6A, and the central portion or two sheets of the strip-shaped separator 54 is formed in the slit 53. The core 51 is rotated about one turn across the end of the overlapped strip-shaped separator 54, and then disposed so that the strip-shaped positive electrode plate or the strip-shaped negative electrode plate is interposed between the separators 54, and the core 51 is rotated. After being wound in a spiral shape, the core 51 is produced by pulling out the winding core 51 from the spirally wound electrode body.

  Thus, when the core 51 is pulled out from the spirally wound electrode body, as shown in FIG. 6B, the center of the space (core trace space) 55 after the core 51 is pulled out. The separator 54 remains so as to divide the core trace space 55 into the part. For this reason, an electrode rod for spot welding to the inner surface of the bottom of a metal outer can that also serves as one terminal with a current collecting tab extending from one current collector of the wound electrode body is provided in the core trace space 55. When it is going to insert in, the separator 54 which remained so that the core trace space 55 might be divided became obstructive, and the spot welding operation was complicated.

  The step of spot welding a current collecting tab extending from one current collector of the wound electrode body to the inner surface of the bottom of the metal outer can is performed as follows. First, as shown in FIG. 7, a current collecting tab 62 extending from one current collector is formed and wound so that the current collecting tab 62 is positioned at the center of the bottom inner surface of the battery outer can 61. The electrode body 60 is inserted into a metal battery outer can 61. Next, one spot welding electrode 63 is inserted into the core trace space 55 formed in the wound electrode body 60, the spot welding electrode 63 is brought into contact with the current collecting tab 62, and the battery outer can 61 is placed. The other spot welding electrode 64 is brought into contact with the outer side of the central portion of the. Thereafter, spot welding is performed between the current collecting tab 62 and the bottom inner surface of the battery outer can 61 by flowing a large current between the spot welding electrodes 63 and 64 in a short time.

Therefore, in order to prevent the separator 54 remaining so as to divide the core trace space 55 from interfering with the spot welding described above, the heated shaping rod 66 is placed in the core trace space 55 as shown in FIG. A shaping step is adopted in which the separator 54 remaining in the core trace space 55 is thermally shaped and displaced in the direction of the inner peripheral wall of the core trace space 55 (see Patent Documents 1 to 4 below). .
Japanese Patent Laid-Open No. 58-066270 Japanese Examined Patent Publication No. 62-043304 Japanese Patent Laid-Open No. 05-225998 Japanese Patent Laid-Open No. 11-273713

  In the conventional shaping process as described above, a heated tapered taper metal rod or the like is used as the shaping rod 66, and the shaping rod 66 is inserted into the center of the core trace space 55 and then the inner wall of the core trace space 55. The separator 54 remaining in the core trace space 55 is thermally shaped and displaced in the direction of the inner peripheral wall of the core trace space 55 by being pressed evenly over the entire circumference. However, in the conventional shaping process, a heated shaping rod is inserted into the center of the battery outer shape with respect to the battery outer shape. Therefore, when the battery outer shape and the center of the center hole are eccentric, Sometimes the separator was crushed.

  Further, in the conventional shaping process, since the tip position of the separator remaining in the core trace space is unknown, after the shaping rod is inserted into the core trace space, the shaping rod is placed around the inner peripheral wall of the core trace space. It had to be pressed evenly over. However, when the separator remaining in the core trace space is thermally shaped and displaced in the direction of the inner peripheral wall of the core trace space, the portion that does not need to be shaped is also pressed, so the most shaping is necessary. There was a problem that the time for pressing the shaping rod to the place was shortened, and the shaping state might not be stable.

  The present invention has been made to solve the above-mentioned problems of the prior art, and its purpose is to recognize the position of the separator remaining in the core trace space and the tip position of the bulge using an image recognition technique, It is an object of the present invention to provide a method for manufacturing a battery in which a shaping rod can be pressed against a location where the shaping of the separator is necessary for a sufficient time so that the separator can be reliably shaped.

  In order to achieve the above object, a method of manufacturing a battery having a wound electrode body according to the present invention includes a separator interposed between a strip-like positive electrode plate and a negative electrode plate, and an end or center portion of the separator as a winding start portion. A step of forming a wound electrode body by spirally winding with a winding core; a step of removing the winding core from the winding electrode body to form a wound electrode body having a core trace space; and the winding electrode And a shaping step of displacing the separator remaining in the core trace space of the body to the inner peripheral wall of the core trace space by a shaping rod, and a method for producing a battery comprising a wound electrode body, wherein the shaping step comprises: In the image recognition step in advance, the position of the separator remaining in the core trace space and the tip position of the bulge are recognized, the circumscribed circle corresponding to the maximum diameter portion of the core trace space, the circumscribed circle and the core Separe that remains in the trace space An inscribed circle having a maximum diameter formed between the inner surface and the shaping rod is inserted into the center of the inscribed circle and then moved toward the center of the inscribed circle. The separator is moved linearly or in a curve toward the tip of the bulge of the separator remaining in the trace space.

  In the method for manufacturing a battery provided with the wound electrode body of the present invention, the shaping step recognizes in advance the position of the separator remaining in the winding core trace space and the tip position of the bulge in the image recognition step, and the winding core trace space. And a maximum inscribed circle formed between the circumscribed circle corresponding to the maximum diameter portion and the separator remaining in the core trace space. In the present invention, the “circumferential circle corresponding to the maximum diameter portion of the core trace space” is a portion substantially corresponding to the diameter of the core core and excluding the separator extending into the core trace space. This corresponds to the inner peripheral diameter of. Note that inserting the shaping rod into the center of the core trace space of the conventional example corresponds to inserting the shaping rod into the center of the “circumferential circle corresponding to the maximum diameter portion of the core trace space” of the present invention. . Further, in the present invention, the “inscribed circle of the maximum diameter formed between the circumscribed circle and the separator remaining in the core trace space” is formed between the circumscribed circle and the separator remaining in the core trace space. Although there are a plurality of inscribed circles, the inscribed circle having the largest diameter among them, that is, the inscribed circle on the side where the distance between the circumscribed circle and the separator remaining in the core trace space is the largest is shown.

  And in the manufacturing method of the battery provided with the wound electrode body of the present invention, a molding rod is first formed at the center of the inscribed circle having the maximum diameter formed between the circumscribed circle and the separator remaining in the core trace space. insert. There may be a separator at the center of the circumscribed circle corresponding to the maximum diameter portion of the core trace space, but the maximum diameter formed between the circumscribed circle and the separator remaining in the core trace space. There is no separator at the center of the inscribed circle. Therefore, according to the manufacturing method of the battery provided with the wound electrode body of the present invention, the separator can be smoothly inserted into the core trace space without being crushed when the shaping rod is inserted.

  Further, in the method for manufacturing a battery including the wound electrode body according to the present invention, a molding rod is inserted at the center of the inscribed circle having the maximum diameter formed between the circumscribed circle and the separator remaining in the core trace space. Then, it is moved toward the center of the circumscribed circle, and then moved linearly or curvedly toward the tip of the bulge of the separator remaining in the core trace space. If such a method is adopted, only the place where the shaping rod needs to be pressed will be pressed, so that the time required for the shaping process remains the same in the core trace space even if it is the same as the case of the conventional example. Since the pressing time against the separator can be lengthened, the separator can be reliably shaped.

  In the battery manufacturing method of the present invention, the shaping rod is further inserted into the core trace space when the tip of the shaping rod enters the inscribed circle in the core trace space. However, it is preferable to move toward the center of the circumscribed circle.

  When such a method is adopted, it is present in the core trace space as compared with the case where all the shaping rods are inserted into the center of the inscribed circle in the core trace space and then moved toward the center of the circumscribed circle. Since the separator is displaced little by little, the resistance when inserting the shaping rod into the core trace space and the resistance required for the displacement of the separator are reduced. Therefore, according to the method for manufacturing a battery of the present invention, it is possible to easily insert the shaping rod and the core trace space without crushing the center hole and to increase the diameter of the shaping rod. Therefore, it is advantageous for the bending of the shaping rod.

  In the battery manufacturing method of the present invention, the shaping step is performed by fixing the wound electrode body having the winding core trace space and moving the shaping rod in three axial directions. Is preferred.

  According to the method for manufacturing a battery of the present invention, the shaping process can be automated easily and is suitable for mass production.

  In the battery manufacturing method of the present invention, it is preferable that the shaping rod has a tapered tip and is heated to a temperature at which the separator can be thermally shaped.

  According to the battery manufacturing method of the present invention, since the tip of the shaping rod is tapered, the shaping rod can be easily inserted into the core trace space without crushing the separator. Since it is heated to a temperature at which heat shaping is possible, the shaping process can be performed with a small force, and abnormal shaping of the core trace space is less likely to occur. For example, in the case of a polyethylene microporous membrane, the heat-shaping temperature is preferably set to 65 to 95 ° C. If it is lower than 65 ° C., shaping tends to be insufficient, and if it is higher than 95 ° C., the separator shrinks and the core trace space tends to be small. For materials other than polyethylene, the temperature at which heat shaping is possible can be appropriately set for the same reason.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiment described below exemplifies a non-aqueous electrolyte secondary battery as an example for embodying the technical idea of the present invention, and is intended to specify the present invention to this embodiment. However, the present invention is equally applicable to other embodiments included in the claims.

  FIG. 1 is a perspective view showing the cylindrical nonaqueous electrolyte secondary battery manufactured in the embodiment cut in the vertical direction. FIG. 2A is an enlarged plan view of the trace from which the winding core has been removed as viewed from the end side of the wound electrode body, FIG. 2B is a diagram showing a portion that does not require the molding of FIG. 2A, and FIG. It is the figure which drawn the circumscribed circle and inscribed circle which were recognized by image recognition about the winding electrode body shown. 3A to 3H are diagrams for explaining the movement of the shaping bar in the separator shaping process step by step. FIG. 4 is a timing chart of each shaping process shown in FIG. 5A is a diagram for explaining the linear motion of the shaping rod of the embodiment, FIG. 5B is a diagram for explaining the curved motion of the shaping rod of the embodiment, and FIG. 5C is a curve of the shaping rod of the conventional example. It is a figure explaining movement of a shape.

  As shown in FIG. 1, the nonaqueous electrolyte secondary battery 10 of the example uses a wound electrode body 14 in which a positive electrode plate 11 and a negative electrode plate 12 are wound in a spiral shape with a separator 13 interposed therebetween. A wound core space 14 a is formed at the center of the wound electrode body 14. Insulating plates 15 and 16 are arranged on the upper and lower sides of the wound electrode body 14, respectively, and are housed inside a cylindrical battery outer can 17 having a bottom that also serves as a negative electrode terminal. The battery outer can 17 is made of, for example, iron with nickel plating on the surface.

  The central portions of the insulating plates 15 and 16 are cut out in the same shape as the opening of the core trace space 14a. And the current collection tab 12a of the negative electrode plate 12 is welded to the inner bottom part of the battery outer can 17, and the current collection tab 11a of the positive electrode plate 11 is the bottom plate of the positive electrode terminal 19 that also serves as the safety valve 18 through the opening formed in the insulating plate 15. It is welded to the part. A non-aqueous electrolyte (not shown) is injected into the battery outer can 17, and the opening of the battery outer can 17 is sealed by a positive electrode terminal 19 that also serves as a safety valve 18.

  An example of a method for producing the positive electrode plate 11 is as follows. First, the positive electrode active material was weighed so that the ratio of lithium nickel cobalt manganese composite oxide: lithium cobaltate = 1: 9 (mass ratio), carbon as the positive electrode conductive agent, polyvinylidene fluoride as the binder ( PVdF) powder is charged into N-methyl-2-pyrrolidone (NMP) at a mass ratio of positive electrode active material: carbon: PVdF = 94: 3: 3 and kneaded to prepare a slurry. This slurry is applied to both surfaces of a 15 μm thick aluminum foil core by the doctor blade method and then dried to form a positive electrode active material layer on both surfaces of the positive electrode current collector. Then, it compresses using a compression roller and the positive electrode plate 11 is produced. The produced positive electrode plate 11 has, for example, a length of 700 mm, a width of 55 mm, and a thickness of 100 μm.

  An example of a method for producing the negative electrode plate 12 is as follows. First, a graphite powder as a negative electrode active material and a dispersion of styrene butadiene rubber (SBR) (styrene: butadiene = 1: 1) as a binder are dispersed in water, and carboxymethyl cellulose (CMC) as a thickener is further dispersed. ) To prepare a negative electrode active material mixture slurry. In addition, the dry mass ratio of this negative electrode active material mixture slurry is prepared such that, for example, graphite: SBR: CMC = 95: 3: 2. The negative electrode active material mixture slurry is applied to both surfaces of a copper foil core having a thickness of 10 μm by the doctor blade method, dried, and then compressed by a compression roller to produce the negative electrode plate 12. The produced negative electrode plate 12 has, for example, a length of 750 mm, a width of 57 mm, and a thickness of 75 μm.

  The spirally wound electrode body 14 wound in a spiral shape is specifically manufactured by the following method. First, the positive electrode plate 11 and the negative electrode plate 12 are overlapped with each other while being insulated from each other with a polyethylene microporous membrane separator 13 interposed therebetween, and wound around a core similar to that of the conventional example shown in FIG. 6A. . Here, in the overlapped state, the separator 13, the positive electrode plate 11, the separator 13, and the negative electrode plate 12 are arranged in this order. The separator 13 is longer and wider than the positive electrode plate 11 and the negative electrode plate 12. On the other hand, the negative electrode plate 12 is wider than the positive electrode plate 11.

  One end of an aluminum current collecting tab 11 a is welded to the winding start portion of the positive electrode plate 11. Similarly, one end of a current collecting tab 12a made of nickel is welded to the winding end portion of the negative electrode plate 12. The current collecting tabs 11a and 12a are flexible flat plates, and their surfaces are covered with an insulating film except for welded portions at both ends. In addition, the outermost periphery of the wound electrode body 14 wound in a spiral shape is stopped with an insulating tape (not shown) so that the wound state is maintained.

  When the winding core is removed in such a state and the winding core trace space 14a is viewed from the end side of the winding electrode body 14, for example, as shown in FIG. 2A. In FIG. 2A, of the separator 13a remaining in the core trace space 14a, the portion surrounded by a circle is the bulging tip position 13b. In the wound electrode body 14 in such a state, for example, a portion 14b drawn by a two-dot chain line in FIG. 2B is a portion that does not require shaping with a shaping rod. Therefore, in the present invention, a commonly used image processing apparatus (not shown) is used, and as shown in FIG. 2C, the position of the separator 13a remaining in the core trace space 14a and the tip position 13b of the bulge are determined. A circumscribed circle CC corresponding to the maximum diameter portion of the core trace space 14a and a maximum diameter inscribed IC formed between the circumscribed circle CC and the separator 13b remaining in the core trace space 14a Ask for.

  Here, the circumscribed circle CC corresponding to the maximum diameter portion of the core trace space 14a is a portion substantially corresponding to the diameter of the core (see FIG. 6A) and remains in the core trace space 14a. This corresponds to the inner periphery of the separator 13 portion excluding the separator 13a portion. In addition, the maximum inscribed circle IC formed between the circumscribed circle CC and the separator 13a remaining in the core trace space 14a is between the circumscribed circle CC and the separator 13a remaining in the core trace space 14a. The inscribed circle IC having the largest diameter among the plurality of formed inscribed circles, that is, the inscribed circle IC on the side where the distance between the circumscribed circle CC and the separator 13a remaining in the core trace space 14a is the longest is shown.

  After obtaining such an image processing recognition process, a shaping process of the separator 13a remaining in the core trace space 14a is performed. This shaping process will be described with reference to FIGS. 3A to 3H, the relative position between the vertical cross section of the wound electrode body 14 and the shaping rod 30 in each stage of the shaping process and the shaping rod 30 as viewed from the end side of the wound electrode body 14. The relative positions are shown at the same time, and some reference numerals are omitted in some drawings. In FIG. 4, the time points corresponding to FIGS. 3A to 3H are shown in parentheses. Here, the wound electrode body 14 is vertically fixed and fixed, and the shaping rod 30 is automatically driven along the X, Y, and Z axes by three-axis control. Further, the shaping rod 30 is tapered and heated to a temperature at which the separator 13 can be thermally shaped, as in the case of the conventional example.

  First, the shaping rod 30 is positioned at the origin O (FIG. 3A). The origin O is also the top dead center position of the shaping rod 30 in the Z-axis direction. Next, the shaping rod 30 is horizontally moved so that the center 30a is positioned on the center A point of the inscribed circle IC (FIG. 3B). Thereafter, the shaping rod 30 is moved down until the center 30a of the shaping rod 30 is positioned at the center B point of the circumscribed circle CC (FIG. 3C). Thereafter, simultaneously with reaching the bottom dead center of the shaping rod 30, the shaping rod 30 is moved toward the bulging tip position 13b of the separator 13a remaining in the core trace space 14a, and remains in the core trace space 14a. The shaping of the separator 13a is started (FIG. 3D). This movement of the shaping rod is a linear movement or a circular movement toward the tip position 13b of the bulge of the separator 13a remaining in the core trace space 14a (FIG. 3E). After the shaping is completed, the shaping rod 30 is returned to the center point of the circumscribed circle CC again, and the raising of the shaping rod is started (FIG. 3F). At the same time that the shaping rod 30 comes out of the post-core space 14a of the wound electrode body 14 (FIG. 3G), the movement to the origin position O is started and the shaping rod 30 is returned to the initial position (FIG. 3H). In this way, the shaping process of the separator 13a remaining in the series of core trace spaces 14a is completed.

  5A and 5B show the movement trajectory of the shaping rod 30 in the shaping process of the present embodiment, and FIG. 5C shows the movement trajectory of the shaping rod 30 of the conventional example. 5A is a locus when the shaping rod 30 is linearly moved toward the tip end position 13b side of the bulge of the separator 13a remaining in the core trace space 14a in FIG. 3E, and FIG. 5B is also the same as FIG. 3E. Is a trajectory when moved in an arc. 5C shows a case where the shaping rod 30 is directly inserted into the center point of the core trace space 14a (equal to the center point of the circumscribed circle) and then moved in an annular shape to shape the entire inner surface of the core trace space 14a. The trajectory.

  5A to 5C, the shaping process according to the present embodiment can recognize a portion that does not require shaping (see FIG. 2B), so that the portion that does not need shaping is not shaped. Only the necessary parts can be directly shaped. On the other hand, in the shaping process of the conventional example, since the portion that does not require shaping is not recognized, the shaping rod 30 is brought into contact with the entire inner surface of the shaped trace space 14a and shaped. Therefore, in the shaping process of the present embodiment, when the time required for the entire shaping process is the same as in the conventional example, the pressing time of the shaping rod 30 is about 0.012 seconds in the conventional example. It becomes possible to secure 0.1 second or more, and the separator 13a remaining in the core trace space 14a can be shaped with certainty.

  The wound electrode 14 having finished the shaping process in this way is subjected to the same welding process as in the conventional example shown in FIG. 7, and if necessary, a center pin is inserted into the core trace space 14a. After injecting a predetermined amount of nonaqueous electrolyte into the battery outer can 17, as shown in FIG. 1, an insulating gasket 21 is brought into contact with the periphery of the positive electrode terminal 19 that also serves as the safety valve 18, so that the positive electrode terminal 19 and the battery outer can 17 The nonaqueous electrolyte secondary battery 10 of the embodiment is obtained by electrically insulating the battery outer can 17 and crimping the tip of the battery outer can 17. The safety valve 18 is provided to discharge gas to the outside of the non-aqueous electrolyte secondary battery 10 when gas is generated inside the non-aqueous electrolyte secondary battery 10 and the pressure inside the battery exceeds a specified value. It is what was done. The size of the nonaqueous electrolyte secondary battery 10 of this embodiment is 18 mm in diameter and 65 mm in height, and the design capacity is 2600 mAh.

As an example of the non-aqueous electrolyte, ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), and methyl ethyl carbonate (MEC) are each 15: 10: 65: 10 (volume ratio, 20 ° C. ) LiPF ₆ dissolved in a mixed solvent so as to become 1 mol / liter can be used.

  In the above embodiment, the case of a non-aqueous electrolyte secondary battery has been described as an example. However, in the present invention, a separator is interposed between the strip-like positive electrode plate and the negative electrode plate, and the end portion or the central portion of the separator is wound. Any battery that uses a spirally wound electrode wound around a winding core as a starting portion can be applied to, for example, a nickel-cadmium secondary battery or a nickel-hydrogen secondary battery.

1 is a perspective view showing a cylindrical nonaqueous electrolyte secondary battery manufactured in an embodiment cut in a vertical direction. FIG. FIG. 2A is an enlarged plan view of the trace from which the winding core has been removed as viewed from the end side of the wound electrode body, FIG. 2B is a diagram showing a portion that does not require the molding of FIG. 2A, and FIG. It is the figure which drawn the circumscribed circle and inscribed circle which were recognized by image recognition about the winding electrode body shown. 3A to 3H are diagrams for explaining the movement of the shaping bar in the separator shaping process step by step. It is a timing chart of the shaping process shown in FIG. 5A is a diagram for explaining the linear motion of the shaping rod of the embodiment, FIG. 5B is a diagram for explaining the curved motion of the shaping rod of the embodiment, and FIG. 5C is a curve of the shaping rod of the conventional example. It is a figure explaining movement of a shape. FIG. 6A is a perspective view showing a state in which the separator is wound around the core, and FIG. 6B is a diagram showing a state in which the core is removed. It is sectional drawing which shows the process of welding one current collection lead of a winding electrode body to the bottom part inner surface of a battery exterior can. It is a perspective view which shows the displacement process of a separator.

Explanation of symbols

10: Nonaqueous electrolyte secondary battery 11: Positive electrode plate 11a: Positive electrode current collecting tab 12: Negative electrode plate 12a: Negative electrode current collecting tab 13: Separator 13a: Separator 13b (remaining in the core trace space) 13b: Tip portion 14: Winding Rotating electrode body 14a: Winding core trace space 15, 16: Insulating plate 17: Battery outer can 18: Safety valve 19: Positive electrode terminal 21: Gasket

Claims (4)

A step of interposing a separator between the belt-like positive electrode plate and the negative electrode plate, and forming a wound electrode body by winding the end or center of the separator in a spiral shape with a winding core as a winding start portion;
Removing the core from the wound electrode body and forming a wound electrode body having a core trace space;
A shaping step of displacing the separator remaining in the core trace space of the wound electrode body to the inner peripheral wall of the core trace space with a shaping rod;
A method for producing a battery comprising a wound electrode body having
The shaping step recognizes the position of the separator remaining in the core trace space and the tip position of the bulge in the image recognition step in advance, and the circumscribed circle corresponding to the maximum diameter portion of the core trace space, and the circumscribed circle A maximum inscribed circle formed between the circle and the separator remaining in the core trace space is obtained, and after the shaping rod is inserted into the center of the inscribed circle, A method for producing a battery having a wound electrode body, wherein the battery is moved linearly or curvedly toward the tip of the bulge of the separator remaining in the core trace space.   The shaping rod is moved toward the center of the circumscribed circle while being further inserted into the core trace space when the tip of the shaping rod enters the inscribed circle in the core trace space. The method for producing a battery according to claim 1.   2. The battery manufacturing method according to claim 1, wherein the shaping step is performed by fixing a wound electrode body having the winding core trace space and moving the shaping rod in three axial directions.   The battery manufacturing method according to claim 1, wherein the shaping rod has a tapered tip and is heated to a temperature at which the separator can be thermally shaped.