JP2012129098A - Manufacturing method and manufacturing apparatus of secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method and a manufacturing apparatus of a secondary battery which prevent displacement of an electrode sheet and a separator, thereby completing a lamination process of electrode sheet in a shorter time to improve the productivity.SOLUTION: A manufacturing method of a secondary battery comprises a separator forming step for forming separators on both faces of an electrode sheet, a mounting step for mounting the electrode sheet on which the separators are formed and another electrode sheet alternately, a positioning step for positioning the electrode sheet and another electrode with using a guide, and an electrode sheet applying step for applying the positioned another electrode sheet to the separator.

Description

  The present invention relates to a method and an apparatus for manufacturing a secondary battery with improved productivity.

  As a method for manufacturing a lithium ion secondary battery or the like, conventionally, a winding method in which an electrode sheet and a separator sheet are wound and stacked has been the mainstream. However, as the capacity of the secondary battery increases, problems such as that stress due to heat generation tends to occur in the wound battery and that the electrolyte is difficult to be injected into the wound battery are pointed out. It has become. Therefore, as a method for producing a safe and high-performance large-capacity secondary battery, a lamination method in which an electrode sheet and a separator sheet are laminated is becoming mainstream.

  Patent Document 1 describes a method for manufacturing a secondary battery by a twisting method. In this method, an electrode plate composed of a plurality of positive and negative electrode plates is disposed on a continuous separator, and another continuous separator is superposed on the continuous separator and adhered by heating. In this way, the continuous separator having the electrode plates attached at predetermined intervals is folded in a fold-like manner so that the electrode plates are alternately overlapped to form a laminated structure, and a secondary battery is manufactured.

  Further, Patent Document 2 describes a method for manufacturing a secondary battery by a stacking method different from the method described in Patent Document 1. In this method, porous separators are stacked on both surfaces, and the cutting part is welded together with the cutting by a cutting mechanism using a punching blade with a heater. Thus, the secondary battery is manufactured by laminating the electrode sheet integrated with the separator together with the electrode sheet of the other electrode.

JP 2009-009919 A JP 2006-324095 A

  However, in the method of manufacturing a secondary battery described in Patent Document 1, a continuous separator having electrode plates bonded together at a predetermined interval is folded in a crooked manner, and the electrode plates are placed one by one in a narrow bag-shaped region. Therefore, there is a problem that a special swing mechanism is required and it is difficult to shorten the time required for the laminating operation. Patent Document 2 does not mention a specific stacking procedure when the separator and the electrode sheet are integrated, but in the secondary battery, the positional deviation of the electrode sheet or the separator causes performance deterioration or short circuit. Therefore, it is required that the positive electrode sheet and the negative electrode sheet are alternately laminated via the separator while preventing the positional deviation.

  Accordingly, an object of the present invention is to provide a method for manufacturing a secondary battery in which the electrode sheet and separator are prevented from being displaced using a relatively simple mechanism, thereby speeding up the electrode sheet stacking process and improving productivity. It is to provide a manufacturing apparatus.

  In order to solve the above problems, a method for manufacturing a secondary battery according to the present invention includes a separator forming step of forming separators on both surfaces of one electrode sheet, the one electrode sheet on which the separator is formed, and another A placement step of alternately placing electrode sheets; a positioning step of positioning the one and other electrode sheets using a guide; and an electrode sheet sticking step of sticking the positioned other electrode sheet to the separator It consists of the method characterized by having.

  According to such a method of manufacturing a secondary battery, the separator is fixed to both surfaces of the one electrode sheet in the separator forming step, so that the one electrode sheet and the separator can be handled integrally. As a result, in the manufacturing process after the separator forming process, an operation for preventing the positional deviation between the one electrode sheet and the separator becomes unnecessary, the manufacturing process is simplified and speeded up, and the productivity is improved.

  Further, in the present invention, since the separator can be handled integrally with one electrode sheet by the separator forming process, it is complicated to prevent misalignment, deflection, deformation and the like of the thin and poorly rigid separator. It is not necessary to adopt a simple holding mechanism. As a result, it is possible to quickly position one and other electrode sheets with a simple guide structure, thereby realizing cost reduction and productivity improvement. Such a guide structure is not particularly limited, but movable walls are arranged on four sides of the placed electrode sheet, and the movable wall moves while contacting the outer peripheral portion of the electrode sheet. The structure which adjusts the position of an electrode sheet is mentioned.

  In the present invention, by alternately placing one electrode sheet having a separator formed on both sides and another electrode sheet, the one electrode sheet and the other electrode sheet are alternately laminated via the separator. Structure is formed. That is, in this laminated structure, one electrode sheet and another electrode sheet are alternately laminated, and a separator is disposed between the adjacent one electrode sheet and the other electrode sheet. . In the present invention, the one and other electrode sheets are positioned by the positioning step, and the separator is formed on the surface of the one electrode sheet by the separator forming step, and the other positioned electrode sheet is attached to the electrode sheet. Since it is affixed to the separator sheet by the process, the positional deviation of each sheet in the above laminated structure is prevented in advance, and the entire laminated structure can be handled integrally. According to such a structure, performance deterioration and short circuit due to displacement of the electrode sheet and separator are prevented in advance, so that a secondary battery having stable battery performance can be provided.

  In the electrode sheet sticking step of the present invention, the method of sticking another electrode sheet to the separator is not particularly limited, and examples thereof include methods such as fusion, welding, pressure bonding, adhesion, application, tightening, stitching, and laminating. be able to.

  The separator forming step preferably includes a coating step of applying a gel electrolyte solution on both surfaces of one electrode sheet, and a fixing step of fixing the applied electrolyte layer on the surface of the one electrode sheet. That is, it is preferable that the separator which consists of an electrolyte solution layer is formed on both surfaces of one electrode sheet by apply | coating a gel electrolyte solution layer to both surfaces of one electrode sheet. In the fixing step described above, the electrolytic solution layer applied to the surface of one electrode sheet may be fixed by means of drying, heating, injection of a curing agent, or may be fixed by natural drying. . By forming the gel electrolyte layer on both sides of the electrode sheet, the permeation time is shortened, liquid leakage is prevented, the electrode sheet is protected by the gel layer, and the amount of electrolyte in each layer is made uniform. It becomes possible to manufacture a secondary battery having high quality and stable battery performance. In addition, the gel layer fixed on both surfaces of one electrode sheet by drying etc. can be handled integrally with one electrode sheet, and positional displacement does not occur, so the manufacturing process by applying electrolyte solution is complicated It can be minimized, and the processing and cutting of one electrode sheet can be easily performed.

  Further, the separator forming step may be an attaching step of attaching the separator sheet to both surfaces of one electrode sheet. By sticking, the separator is fixed to both surfaces of one electrode sheet while being fixed to prevent displacement, so that the separator can be handled integrally with one electrode sheet, simplifying the manufacturing process and improving productivity. Improvement is realized. As described above, the method for attaching the separator sheet to one electrode sheet is not particularly limited, and examples thereof include fusion, welding, pressure bonding, adhesion, tightening, stitching, and laminating methods.

  In the separator pasting step described above, it is preferable that the one electrode sheet and the separator sheet are pasted in a state of being pulled out from the roller. By using the roller, it becomes possible to precisely control the conveyance of each sheet, and the separator sheet can be uniformly attached to both surfaces of one electrode sheet. At this time, it is preferable that the conveyance of the one electrode sheet and the separator sheet is controlled so that the one electrode sheet does not protrude from the separator sheet in the width direction.

  The method for producing a secondary battery in the present invention preferably includes a separator cutting step of cutting the separator sheet in a state where the separator sheet is attached to one electrode sheet after the separator sheet is attached. Thereby, the separator sheet can be processed into a desired size and shape in a state where the separator sheet and the one electrode sheet are integrated, and the degree of freedom in designing the secondary battery is increased. Also, since the separator sheet is affixed to one electrode sheet, there is no need to use a pressing mechanism or welding means for fixing the position of the separator sheet to the one electrode sheet at the time of cutting, simplifying the cutting process Is realized.

  In the present invention, the polarity and size of one and other electrode sheets are not particularly limited. For example, one electrode sheet may be a negative electrode sheet, and the other electrode sheet may be a positive electrode sheet, or vice versa. The size of one and other electrode sheets is not particularly limited, but the size of the separator sheet is the same as or larger than that of the negative electrode sheet in order to prevent short circuit due to contact between the positive electrode sheet and the negative electrode sheet. The size of the negative electrode sheet is the same as or larger than that of the positive electrode sheet. Moreover, although the terminal attached to the positive electrode sheet may protrude from the negative electrode sheet, the positive electrode sheet itself is preferably laminated so as not to protrude from the negative electrode sheet.

  It is preferable that the manufacturing method of the secondary battery in the present invention includes a permeation step of permeating the electrolytic solution between the laminated one electrode sheet and the other electrode sheet. By infiltrating the electrolytic solution in this way, the amount of the electrolytic solution between the electrodes can be made uniform to prevent uneven injection, and a secondary battery having stable battery performance can be provided.

  In order to solve the above-described problem, a secondary battery manufacturing apparatus according to the present invention includes separator forming means for forming a separator on both surfaces of one electrode sheet, and the separator is formed on the surface of the one electrode sheet. Separator cutting means for cutting in a state in which the separator is formed, mounting means for alternately stacking the one electrode sheet on which the separator is formed and another electrode sheet, and positioning the one and other electrode sheets using a guide And an electrode sheet sticking means for sticking the other electrode sheet positioned to the separator.

  According to such a secondary battery manufacturing apparatus of the present invention, the separator can be integrally handled with the one electrode sheet by forming the separator on both surfaces of the one electrode sheet by the separator forming means. Therefore, a complicated pressing mechanism is not required, and cost reduction and speedup of the manufacturing process are realized. In addition, by stacking one electrode sheet with the separator sheet on both sides by the mounting means and the other electrode sheet alternately and pasting the other electrode sheet to the separator by the electrode sheet pasting means, the position of each sheet is shifted. Therefore, it is possible to provide a secondary battery having a stable battery performance. Furthermore, since the separator sheet is affixed to one electrode sheet, a pressing mechanism and welding means for fixing the position of the separator sheet to the one electrode sheet at the time of cutting become unnecessary, and the separator cutting means can be simplified. Realized.

  In the above secondary battery manufacturing apparatus, in order to manufacture a secondary battery having high-quality and stable battery performance, after applying a gel electrolyte on both surfaces of one electrode sheet, the applied electrolyte layer It is preferable that a separator is formed by fixing.

  Or said separator formation means may form a separator by sticking a separator sheet on both surfaces of one electrode sheet. If it does in this way, it will become possible to handle a separator and one electrode sheet integrally by sticking, and simplification of a manufacturing process and improvement of productivity will be realized.

  In the secondary battery manufacturing apparatus, the polarities of the one and other electrode sheets are not particularly limited. For example, one electrode sheet may be a negative electrode sheet, and the other electrode sheet may be a positive electrode sheet, or vice versa.

  According to the method for manufacturing a secondary battery and the apparatus for manufacturing a secondary battery according to the present invention, by forming the separator on both surfaces of one electrode sheet, the separator can be handled integrally with the one electrode sheet. Therefore, a complicated pressing mechanism is not required, and cost reduction and speedup of the manufacturing process are realized.

It is the schematic which shows the manufacturing method of the secondary battery which concerns on one embodiment of this invention. It is the schematic which shows the laminated structure of the secondary battery manufactured by the manufacturing method of the secondary battery shown in FIG. It is a top view of the guide as a positioning means used in the manufacturing method of the secondary battery shown in FIG. It is the schematic which shows the manufacturing method of the secondary battery which concerns on the other embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a separator forming step, a separator cutting step, and a placing step in a method for manufacturing a secondary battery according to an embodiment of the present invention, wherein (A) is a schematic plan view, and (B) is a schematic front view. FIG. In this embodiment, one electrode sheet is the negative electrode sheet 2 and the other electrode sheet is the positive electrode sheet 8. In FIG. 1, the negative electrode sheet 2 wound around the outer periphery of the roller 1 a is pulled out from the roller 1 a, and the terminal 3 is formed at one end in the width direction of the negative electrode sheet 2 using the terminal forming means 4. Next, a set of separator sheets 5 a pulled out from the roller 1 b are pasted on both surfaces of the negative electrode sheet 2 by the separator pasting means 6 as separator forming means, and the separator 5 is formed on both surfaces of the negative electrode sheet 2. At this time, a part of the terminal 3 is exposed from the separator sheet 5a, but the negative electrode sheet 2 itself is controlled so as not to protrude from the separator sheet 5a in the width direction. The negative electrode sheet 2 with the separators 5 attached on both sides is cut to a predetermined size by the separator cutting means 7 and then sent to the placing means 10.

  On the other hand, the positive electrode sheet 8 wound around the outer periphery of the roller 1 c is drawn from the roller 1 c, and the terminal 23 is formed at one end in the width direction of the positive electrode sheet 8 from the terminal material 23 a using the terminal forming means 4. The positive electrode sheet 8 on which the terminals 23 are formed is cut into a predetermined size by the sheet cutting means 9 and then sent to the placing means 10. The positive electrode sheet 8 is slightly narrower than the negative electrode sheet 2, and the positive electrode sheet 8 cut to a predetermined size by the sheet cutting means 9 is cut to a predetermined size by the separator cutting means 7. The negative electrode sheet 2 has a slightly smaller area.

  FIG. 2 shows a laminated structure of the secondary battery manufactured by the method for manufacturing the secondary battery shown in FIG. In FIG. 2, the negative electrode sheet 2 has a structure in which negative electrode material layers 12 are provided on both front and back surfaces of a copper foil 11, and the positive electrode sheet 8 has a structure in which positive electrode material layers 14 are provided on both front and back surfaces of an aluminum foil 13. It has become. Also, terminals 3 and 23 are electrically connected to the exposed portion of the copper foil 11 in the negative electrode sheet 2 and the exposed portion of the aluminum foil 13 in the positive electrode sheet 8, respectively.

  FIG. 3 is a plan view showing a guide as positioning means used in the method of manufacturing the secondary battery shown in FIG. In FIG. 2, movable flat walls 17 (17 a to 17 f) are erected so as to face the four sides of the guide 16, and the movable walls 17 come into contact with the outer peripheral portion of a substantially rectangular electrode sheet (not shown). The position of the electrode sheet placed in the center of the guide 16 is adjusted by moving while moving. Each movable wall 17 may operate independently, or may operate simultaneously in cooperation. As described above, although the positive electrode sheet 8 is slightly smaller than the negative electrode sheet 2, the positive electrode sheet 8 protrudes from the negative electrode sheet 2 during lamination because the displacement is prevented by the movable wall 17 provided to face the four sides. There is nothing. In addition, since the thin separator 5 having low rigidity is formed on both surfaces of the negative electrode sheet 2 in advance, there is no need to worry about the displacement, deflection, or deformation of the separator 5 due to the contact or movement of the movable wall 17. As a result, it is possible to quickly position the negative electrode sheet 2 and the positive electrode sheet 8 by the movable wall 17, and an improvement in productivity is realized.

  The guide 16 is installed in the vicinity of the mounting means 10 in FIG. 1, and positioning when the negative electrode sheet 2 cut to a predetermined size and the positive electrode sheet 8 cut to a predetermined size are alternately mounted. Used to do. As a result of the negative electrode sheet 2 and the positive electrode sheet 8 on which the separators 5 are formed in advance are alternately placed by the placing means 10 and the negative electrode sheet 2 and the positive electrode sheet 8 are positioned by the guide 16, the negative electrode sheet is obtained. 2 and a positive electrode sheet 8 are laminated in a predetermined position via the separator 5 to form a laminated structure 15. In this laminated structure 15, the negative electrode sheet 2 and the positive electrode sheet 8 are alternately laminated, and the separator 5 is disposed between the adjacent negative electrode sheet 2 and positive electrode sheet 8. As described above, since the separator 5 is pasted on both surfaces of the negative electrode sheet 2 in advance by the separator pasting means 6, the positive electrode sheet 8 positioned by the guide 16 is pasted on the separator 5 by the electrode sheet pasting means (not shown). By adhering, the adjacent negative electrode sheet 2 and the positive electrode sheet 8 can be stuck through the separator 5, and the entire laminated structure 15 can be handled integrally. Then, the terminals 3 of the laminated negative electrode sheet 2 are joined together, and the terminals 23 of the laminated positive electrode sheet 8 are joined together. According to such a structure, performance deterioration and short circuit due to displacement of the electrode sheet and separator sheet are prevented in advance, so that a secondary battery having stable battery performance can be provided.

  4A and 4B show a separator forming step, a separator cutting step, and a placing step in a method for manufacturing a secondary battery according to another embodiment of the present invention, wherein FIG. 4A is a schematic plan view, and FIG. 4B is a schematic diagram. It is a front view. In FIG. 4, between the terminal forming means 4 and the separator cutting means 7, an electrolytic solution applying means 18 and a fixing means 19 as separator attaching means are arranged. The gel electrolyte layer 20 applied to both surfaces of the negative electrode sheet 2 by the electrolytic solution applying means 18 is fixed on the surface of the negative electrode sheet 2 by the fixing means 19, and becomes the separator 5 in close contact with both surfaces of the negative electrode sheet 2. A method for fixing the gel layer on the surface of the negative electrode sheet 2 is not particularly limited, and examples thereof include drying and injection of a curing agent. Other embodiments are the same as those in the method for manufacturing the secondary battery shown in FIG. Then, the terminals 3 of the laminated negative electrode sheet 2 are joined together, and the terminals 23 of the laminated positive electrode sheet 8 are joined together. In this way, by forming the separator 5 composed of the gel electrolyte layer on both surfaces of the negative electrode sheet 2, a secondary battery having high quality and stable battery performance is produced while minimizing the complexity of the production process. It becomes possible to do.

  The method and apparatus for producing a secondary battery according to the present invention can be used as a method and apparatus for producing a lithium ion secondary battery or the like.

1a, 1b, 1c Roller 2 Negative electrode sheet 3, 23 Terminal 3a, 23a Terminal material 4 Terminal forming means 5 Separator 5a Separator sheet 6 Pasting means 7, 9 Cutting means 8 Positive electrode sheet 10 Mounting means 11 Copper foil 12 Negative electrode material layer 13 Aluminum foil 14 Positive electrode material layer 15 Laminated structure 16 Guides 17, 17 a to 17 f Movable wall 18 Application means 19 Fixing means 20 Electrolyte layer

Claims (13)

  A separator forming step for forming separators on both surfaces of one electrode sheet, a placing step for alternately placing the one electrode sheet on which the separator is formed and another electrode sheet, and the one using a guide. And a method of manufacturing a secondary battery, comprising: a positioning step of positioning another electrode sheet; and an electrode sheet attaching step of attaching the positioned other electrode sheet to the separator.   2. The secondary battery according to claim 1, wherein the separator forming step includes a coating step of applying a gel electrolyte solution on both surfaces of the one electrode sheet, and a fixing step of fixing the applied gel electrolyte solution. Production method.   The method for manufacturing a secondary battery according to claim 1, wherein the separator forming step includes a step of attaching a separator sheet to both surfaces of one electrode sheet.   The method for manufacturing a secondary battery according to claim 3, wherein the one electrode sheet and the separator sheet are attached in a state of being pulled out from a roller.   The method for manufacturing a secondary battery according to claim 4, wherein the one electrode sheet is stuck so as not to protrude from the separator sheet in a width direction.   The manufacturing method of the secondary battery in any one of Claims 3-5 which has the separator cutting process which cut | disconnects the said separator sheet in the state affixed on the said one electrode sheet.   The method for producing a secondary battery according to claim 1, wherein the one electrode sheet is a negative electrode sheet, and the other electrode sheet is a positive electrode sheet.   The method for producing a secondary battery according to claim 7, wherein the positive electrode sheet is laminated so as not to protrude from the negative electrode sheet.   The manufacturing method of the secondary battery in any one of Claims 1-8 which has the osmosis | permeation process which osmose | permeates electrolyte solution between said one electrode sheet and said other electrode sheet | seat laminated | stacked.   Separator forming means for forming a separator on both surfaces of one electrode sheet, separator cutting means for cutting the separator in a state formed on the surface of the one electrode sheet, and the one electrode sheet on which the separator is formed Mounting means for alternately stacking and other electrode sheets, positioning means for positioning the one and other electrode sheets using a guide, and electrode pasting means for pasting the positioned other electrode sheets to the separator An apparatus for manufacturing a secondary battery, comprising:   11. The secondary battery according to claim 10, wherein the separator forming unit forms a separator by applying a gel electrolyte on both surfaces of the one electrode sheet and then fixing the applied gel electrolyte. 11. Manufacturing equipment.   The manufacturing apparatus of the secondary battery according to claim 10, wherein the separator forming unit forms a separator by sticking a separator sheet on both surfaces of the one electrode sheet. The manufacturing apparatus of the secondary battery according to claim 10, wherein the one electrode sheet is a negative electrode sheet and the other electrode sheet is a positive electrode sheet.

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