JP2019040837A - Sealed battery - Google Patents

Abstract

To provide a sealed battery in which a collector terminal can be favorably welded to an electrode body and an effect on the electrode body in welding is suppressed.SOLUTION: A positive electrode collector terminal 11 includes a pedestal 22, a plurality of legs 23A-23D, and plate members 24A, 24B. The plate member 24A is configured to be provided to the leg 23B, extend toward the leg 23A adjacent to the outside of the leg 23B and restrict the movement of the leg 23A in a direction of the electrode body while allowing the movement of the leg 23A in a direction of the leg 23B. The plate member 24B is configured to be provided to the leg 23C, extend toward the leg 23D adjacent to the outside of the leg 23C and restrict the movement of the leg 23D in a direction of the electrode body while allowing the movement of the leg 23D in a direction of the leg 23C.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to a sealed battery, and more particularly, to a configuration of a current collecting terminal provided in the sealed battery.

  Japanese Patent Laying-Open No. 2007-299536 (Patent Document 1) discloses a sealed prismatic non-aqueous electrolyte secondary battery. The sealed battery includes an electrode body having an edge portion in a state where uncoated portions to which an electrode active material of a sheet-like electrode plate is not applied are laminated, and a current collecting terminal welded to the edge portion of the electrode body With. The current collector terminal has a plurality of slits, and the current collector (electrode body) and the current collector terminal are welded with the current collector at the edge of the electrode body being inserted into these slits. (See Patent Document 1).

JP 2007-299536 A

  When the current collector of the electrode body is inserted into the slit and the current collector and the current collector terminal are welded (generally laser welding), the current collector should be firmly sandwiched between the slits. The current collector and the current collector terminal are welded in a state in which the current collector terminal is deformed by applying an external force (clamping force) to the current collector terminal.

  However, when the current collector terminal is deformed, if a gap remains in the slit due to twisting of the leg portion forming the slit, laser light may come off from the gap during welding or may occur with welding. Otherwise, the metal pieces may be scattered on the electrode body side and affect the electrode body.

  The present disclosure has been made in order to solve such a problem, and an object of the present disclosure is to make it possible to satisfactorily weld the current collecting terminal to the electrode body and to suppress the influence on the electrode body during welding. Type battery.

  The sealed battery according to the present disclosure includes an electrode body and a current collecting terminal. The electrode body includes a plurality of stacked electrode plates, and a current collector is formed on a side surface along the stacking direction of the plurality of electrode plates. The current collector terminal is welded to the current collector. The current collecting terminal includes a pedestal, a plurality of legs, and a member. The plurality of leg portions extend along the side surface of the electrode body at intervals from the pedestal portion. The current collector is sandwiched between the plurality of legs and welded to the plurality of legs. The member is provided on one leg portion of the plurality of leg portions and extends from the one leg portion toward another leg portion adjacent to the outside thereof, and the one leg portion of the other leg portion. The movement of the other leg portion in the direction of the electrode body is restricted while allowing the movement in the direction of.

  In the sealed battery according to the present disclosure, the members as described above are provided in the current collecting terminal, so that twisting of the leg portion is suppressed when the current collector of the electrode body is sandwiched between the plurality of leg portions. As a result, the current collector can be firmly sandwiched between the plurality of legs without any gaps, so that good welding is performed, and laser light is emitted from the gaps during welding, which is caused by welding. It can suppress that a metal piece scatters to the electrode body side. Thus, according to the sealed battery of the present disclosure, the current collecting terminal can be well welded to the electrode body, and the influence on the electrode body during welding can be suppressed.

1 is a cross-sectional view of a sealed battery according to an embodiment of the present disclosure. It is a top view at the time of seeing the positive electrode current collection terminal attached to the electrode body to a X direction. It is a top view of a positive electrode current collection terminal at the time of seeing a positive electrode current collection terminal from the -X direction (from the electrode body side). FIG. 4 is a cross-sectional view taken along IV-IV in FIG. 3. It is sectional drawing which showed typically the mode at the time of applying the external force (clamping force) to a leg part and closing the slit between leg parts. It is sectional drawing which showed typically the mode at the time of applying the external force (clamping force) to a leg part and closing the slit between leg parts. It is sectional drawing which showed typically the mode at the time of applying the external force (clamping force) to a leg part and closing the slit between leg parts. It is a flowchart which shows the manufacturing process of a sealed battery. It is a top view of a positive electrode sheet. It is a top view of a negative electrode sheet. It is a perspective view of an electrode body. It is a perspective view of an electrode body. It is the figure which showed typically a mode that the positive electrode electrical power collector was shape | molded in current collector preforming process S2. It is the figure which showed typically a mode that the positive electrode electrical power collector was shape | molded in current collector preforming process S2. It is a top view before a positive electrode current collection terminal is shape | molded. It is the figure which showed a mode that the plate member was attached to the positive electrode current collection terminal. It is the figure which showed a mode that the positive electrode external terminal and the negative electrode external terminal, the positive electrode current collection terminal, and the negative electrode current collection terminal were assembled | attached to the cover of the storage case. It is the figure which showed a mode that the cover of the storage case, the positive electrode current collection terminal, and the negative electrode current collection terminal were assembled | attached to the electrode body. It is the figure which showed a mode that the positive electrode current collection terminal was assembled | attached to an electrode body. It is a perspective view which shows a mode that a positive electrode collector is welded to the leg part of a positive electrode current collection terminal. It is sectional drawing which shows a mode that a positive electrode collector is welded to the leg part of a positive electrode current collection terminal. It is sectional drawing which shows a mode that a positive electrode collector is welded to the leg part of a positive electrode current collection terminal. It is sectional drawing which shows a mode that a positive electrode collector is welded to the leg part of a positive electrode current collection terminal. It is a top view of the positive electrode current collection terminal at the time of seeing the positive electrode current collection terminal in a comparative example from the electrode body side. It is a top view at the time of seeing the positive electrode current collection terminal in a comparative example in the Y direction. It is sectional drawing which showed typically the leg part of the positive electrode current collection terminal at the time of the current collection terminal pressurization process in a comparative example. It is sectional drawing which showed typically the leg part of the positive electrode current collection terminal at the time of the current collection terminal pressurization process in a comparative example. It is sectional drawing which showed a mode that the positive electrode electrical power collector was welded to the leg part of the positive electrode current collection terminal in a comparative example. It is the figure which showed the evaluation result of welding with a current collection terminal and a collector in the sealed battery according to embodiment of this indication, and the sealed battery of a comparative example. It is a top view of the positive electrode current collection terminal at the time of seeing the positive electrode current collection terminal in the modification 1 of embodiment from the -X direction (from the electrode body side). It is sectional drawing in alignment with XXXI-XXXI in FIG. It is a top view of a positive electrode current collection terminal at the time of seeing the positive electrode current collection terminal in modification 2 of an embodiment from the -X direction (from the electrode body side). FIG. 33 is a cross-sectional view taken along XXXIII-XXXIII in FIG. 32. It is a top view of the positive electrode current collection terminal at the time of seeing the positive electrode current collection terminal in modification 3 of an embodiment from the -X direction (from the electrode body side). In the modification 3, it is a top view at the time of seeing the positive electrode current collection terminal attached to the electrode body to a X direction.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals and description thereof will not be repeated.

<Overall configuration of sealed battery>
FIG. 1 is a cross-sectional view of a sealed battery 1 according to an embodiment of the present disclosure. With reference to FIG. 1, the sealed battery 1 includes a housing case 2, an electrode body 3, an electrolytic solution 6, a positive electrode external terminal 9, a negative electrode external terminal 10, a positive electrode current collector terminal 11, and a negative electrode current collector. And a terminal 12. A positive electrode current collector 7 is formed on the side surface 4 of the electrode body 3, and a negative electrode current collector 8 is formed on the side surface 5 of the electrode body 3. The electrode body 3, the positive electrode current collector terminal 11, and the negative electrode current collector terminal 12 are housed in the housing case 2, and the electrolytic solution 6 is injected into the housing case 2.

  The housing case 2 includes a case body 20 and a lid 21. The case body 20 has an opening that opens upward. The lid 21 is disposed so as to close the opening of the case body 20, and the lid 21 is welded to the case body 20. A positive electrode external terminal 9 and a negative electrode external terminal 10 are disposed on the upper surface of the lid 21.

  The electrode body 3 includes a plurality of positive electrode sheets, a plurality of separators, and a plurality of negative electrode sheets (each not shown). The electrode body 3 is formed by alternately laminating positive electrode sheets and negative electrode sheets with a separator interposed therebetween.

  The positive electrode current collector 7 is formed by stacking the end portions of the respective positive electrode sheets, and constitutes the positive electrode of the electrode body 3. The negative electrode current collector 8 is formed by laminating end portions of the respective negative electrode sheets, and constitutes the negative electrode of the electrode body 3.

  The positive electrode current collecting terminal 11 includes a pedestal part 22, a leg part 23, and a plate member 24. The pedestal portion 22 is disposed on the upper surface of the electrode body 3 (the −Y direction of the electrode body 3), and is electrically connected to the positive electrode external terminal 9 through a hole formed in the lid 21. The leg portion 23 is connected to the pedestal portion 22 and is provided so as to extend in the Y direction along the side surface 4 of the electrode body 3. The leg portion 23 is welded to the positive electrode current collector 7. Although not shown in FIG. 1, the leg portion 23 is composed of a plurality of leg portions that extend along the side surface 4 at intervals (slits).

  The plate member 24 is a surface facing the electrode body 3 of the leg portion 23, and is provided above (on the pedestal portion 22 side) the connection portion between the leg portion 23 and the positive electrode current collector 7. The plate member 24 has a plurality of leg portions constituting the leg portion 23 when the positive electrode current collector 7 is sandwiched between slits of the leg portion 23 when the leg portion 23 and the positive electrode current collector 7 are connected (welded). It is a member for suppressing arrangement disorder. The arrangement and configuration of the plate member 24 will be described in detail later.

  The negative electrode current collecting terminal 12 includes a pedestal portion 25, a leg portion 26, and a plate member 27. The pedestal 25 is also disposed on the upper surface of the electrode body 3 (the −Y direction of the electrode body 3), and is electrically connected to the negative electrode external terminal 10 through a hole formed in the lid 21. The leg portion 26 is connected to the pedestal portion 25 and is provided so as to extend in the Y direction along the side surface 5 of the electrode body 3. The leg portion 26 is welded to the negative electrode current collector 8. Although not shown in FIG. 1, the leg portion 26 is also composed of a plurality of leg portions extending along the side surface 5 with a space (slit) therebetween.

  The plate member 27 is a surface of the leg portion 26 facing the electrode body 3, and is provided above the connection portion between the leg portion 26 and the negative electrode current collector 8 (on the pedestal portion 25 side). The plate member 27 has a plurality of leg portions constituting the leg portion 26 when the negative electrode current collector 8 is sandwiched between slits of the leg portion 26 when the leg portion 26 and the negative electrode current collector 8 are connected (welded). It is a member for suppressing arrangement disorder.

<Configuration of current collector terminal>
FIG. 2 is a plan view when the positive electrode current collecting terminal 11 attached to the electrode body 3 is viewed in the X direction. 3 is a plan view of the positive electrode current collector terminal 11 when the positive electrode current collector terminal 11 is viewed from the −X direction (from the electrode body 3 side), and FIG. 4 is a cross-sectional view taken along IV-IV in FIG. FIG. In addition, the structure of the negative electrode current collection terminal 12 is the same as that of the positive electrode current collection terminal 11, and the positive electrode current collection terminal 11 is typically demonstrated below.

  2 to 4, the leg portion 23 of the positive electrode current collecting terminal 11 is constituted by four leg portions 23A to 23D. Note that the number of leg portions is not limited to four, and may be more or less. A gap (slit) is provided between the leg portions 23A to 23D. The positive electrode current collector 7 is gathered close to the slit and inserted into the slit. Then, while applying an external force (narrow force) from both sides of the leg portions 23A to 23D so as to narrow the width of the slit, the positive electrode current collector 7 inserted into the slit is irradiated with laser light, whereby the leg is welded at the welded portion 28. The parts 23A to 23D are welded to the positive electrode current collector 7 (FIG. 2).

  The plate member 24 is composed of plate members 24A and 24B. The plate members 24A and 24B are provided above the positive electrode current collector 7 of the electrode body 3 (on the side closer to the pedestal section 22) on the back surface side (electrode body 3 side) of the leg portion 23. The plate members 24A and 24B are joined to the leg portions 23B and 23C by the joining portion 29, respectively. Then, the plate member 24A extends from the leg portion 23B toward the leg portion 23A adjacent to the outside thereof, and is formed so as to cover the leg portion 23A. The plate member 24B extends from the leg portion 23C toward the leg portion 23D adjacent to the outside thereof, and is formed so as to cover the leg portion 23D.

  By providing such a plate member 24, when welding the leg portions 23A to 23D and the positive electrode current collector 7, the positive electrode current collector 7 is sandwiched between slits between the leg portions 23A to 23D and the leg portions 23A to 23D are inserted. When an external force (narrow force) is applied from both sides, the disorder of the arrangement of the leg portions 23A to 23D is suppressed. As a result, the positive electrode current collector 7 is firmly sandwiched between the leg portions 23A to 23D without a gap, so that a good welding is performed in the welded portion 28, and laser light is emitted from the gap during welding or welding. It can suppress that the metal piece which arose with scattering to the electrode body 3 side.

  5 to 7 are cross-sectional views schematically showing a state in which an external force (clamping force) is applied to the leg portions 23A to 23D to close the slit between the leg portions 23A to 23D. FIG. 5 shows the arrangement of the legs 23A-23D before the slit is closed. FIG. 6 shows the arrangement of the legs 23A to 23D when the slits between the legs 23A and 23B and the slits between the legs 23C and 23D are closed by applying a clamping force to the legs 23A to 23D. FIG. 7 shows the arrangement of the leg portions 23A to 23D when the slit between the leg portions 23B and 23C is also closed by further applying a clamping force. Actually, since the positive electrode current collector 7 is sandwiched between the leg portions 23A to 23D, the slit is not completely closed as shown in FIGS.

  As shown in FIG. 6, when the leg portions 23A and 23D are moved (deformed) in the Z direction by applying an external force (clamping force) in the Z direction to the leg portions 23A and 23D so as to close the slit, the leg portion 23A , 23D are connected to the pedestal 22 (not shown), a torsional moment as indicated by an arrow is generated in the legs 23A, 23D. However, in sealed battery 1 according to the present embodiment, plate members 24A and 24B serve as stoppers to suppress twisting of leg portions 23A and 23D. As a result, as shown in FIG. 7, the torsion of the leg portions 23B and 23C that receive loads from the leg portions 23A and 23D, respectively, is also suppressed.

  In this way, the plate member 24A (24B) that restricts the movement of the leg 23A (23D) in the direction of the electrode body 3 while allowing the movement of the leg 23A (23D) in the direction of the leg 23B (23C). ), The twisting of the leg portions 23A to 23D is suppressed and the arrangement of the leg portions 23A to 23D is disturbed when the positive electrode current collector 7 is gathered and sandwiched between the slits between the leg portions 23A to 23D. Is suppressed.

<Method for producing sealed battery>
FIG. 8 is a flowchart showing the manufacturing process of the sealed battery 1. Referring to FIG. 8, the manufacturing process of sealed battery 1 includes an electrode body forming step S1, a current collector pre-forming step S2, a current collecting terminal forming step S3, a plate plate attaching step S4, and a lid forming step. S5, lid / electrode assembly process S6, collector terminal pressurizing process S7, collector terminal welding process S8, housing process S9, lid welding process S10, injection process S11, and sealing process S12 Including.

  In the electrode body forming step S1, a plurality of positive electrode sheets and negative electrode sheets are produced, and the electrode bodies 3 are formed by alternately laminating positive electrode sheets and negative electrode sheets sequentially with an insulator separator interposed therebetween.

  FIG. 9 is a plan view of the positive electrode sheet. Referring to FIG. 9, the positive electrode sheet 30 has a rectangular active material mixture layer 31 applied to the front and back surfaces of the aluminum alloy foil sheet, and a non-applied portion provided on one side of the aluminum alloy foil sheet has a predetermined size. And the uncoated foil part 32 cut into two pieces. The uncoated foil portion 32 is a portion where the active material mixture layer 31 is not formed in the positive electrode sheet 30, and is a portion where the aluminum alloy foil sheet is exposed from the active material mixture layer 31. The uncoated foil part 32 becomes the positive electrode current collector 7 when the electrode body 3 is formed by laminating the positive electrode sheet 30, the negative electrode sheet 33 and the separator.

  FIG. 10 is a plan view of the negative electrode sheet. Referring to FIG. 10, the negative electrode sheet 33 has a rectangular active material mixture layer 34 applied to the front and back surfaces of the copper foil sheet, and an uncoated portion provided on one side of the copper foil sheet is cut to a predetermined size. Uncoated foil portion 35. The uncoated foil portion 35 is a portion where the active material mixture layer 34 is not formed in the negative electrode sheet 33, and is a portion where the copper foil sheet is exposed from the active material mixture layer 34. The uncoated foil portion 35 becomes the negative electrode current collector 8 when the positive electrode sheet 30, the negative electrode sheet 33 and the separator are laminated to form the electrode body 3.

  FIG. 11 is a perspective view of the electrode body 3. Referring to FIG. 11, in electrode body 3, positive electrode sheets 30 (FIG. 9) and negative electrode sheets 33 (FIG. 10) are alternately and sequentially stacked with a separator (not shown) including a porous insulating layer interposed therebetween. Formed by. At this time, the plurality of positive electrode sheets 30 are laminated so that the uncoated foil portions 32 of the respective positive electrode sheets 30 are aligned as illustrated, and the positive electrode current collector 7 is configured by the laminated uncoated foil portions 32. Is done.

  Although not shown in the drawing, the plurality of negative electrode sheets 33 are laminated so that the uncoated foil portions 35 of the respective negative electrode sheets 33 are aligned on the side opposite to the uncoated foil portions 32 of the positive electrode sheet 30. The uncoated foil portion 35 constitutes the negative electrode current collector 8.

  Referring again to FIG. 8, in current collector pre-forming step S <b> 2, positive electrode current collector 7 is formed so that positive electrode current collector 7 can be inserted into the slit between legs 23 </ b> A to 23 </ b> D of positive electrode current collector terminal 11. Is done. In this embodiment, as shown in FIG. 12, the positive electrode current collector 7 is formed into three aggregates according to the number of slits (three) of the positive electrode current collector terminal 11. Although not shown, the negative electrode current collector 8 is formed on the negative electrode side so that the negative electrode current collector 8 can be inserted into the slit between the legs of the negative electrode current collector terminal 12.

  FIGS. 13 and 14 are diagrams schematically showing how the positive electrode current collector 7 is formed in the current collector pre-forming step S2. With reference to FIG. 13 and FIG. 14, the positive electrode current collector 7 is formed using the foil collecting jigs 50 and 51. The foil collection jigs 50 and 51 have convex ends, and after the foil collection jigs 50 and 51 are moved toward the positive electrode current collector 7, the positive electrode collection is performed by the foil collection jigs 50 and 51. The positive electrode current collector 7 is molded (brazed) by sandwiching the electric body 7 therebetween.

  Referring to FIG. 8 again, in current collector terminal forming step S3, positive electrode current collector terminal 11 and negative electrode current collector terminal 12 are manufactured.

  FIG. 15 is a plan view before the positive electrode current collector terminal 11 is shaped. Referring to FIG. 15, positive electrode current collector terminal 11 is made of aluminum, and an original plate of positive electrode current collector terminal 11 is formed by punching an aluminum plate with a predetermined mold. The original plate is provided with a pedestal portion 22 and leg portions 23A to 23D extending from the pedestal portion 22, and the positive electrode current collecting terminal 11 is formed by being bent at 90 degrees along the dotted line in the figure. Although not shown, the negative electrode current collector terminal 12 is made of copper, and the negative electrode current collector terminal 12 is formed by punching a copper plate with a predetermined mold, and is bent in the same manner as the positive electrode current collector terminal 11. A negative electrode current collecting terminal 12 is formed.

  Referring to FIG. 8 again, in the plate plate attaching step S4, the plate member 24 is attached to the positive electrode current collecting terminal 11, and the plate member 27 is attached to the negative electrode current collecting terminal 12.

  FIG. 16 is a diagram illustrating a state where the plate member 24 is attached to the positive electrode current collecting terminal 11. Referring to FIG. 16, pedestal portion 22 is bent at 90 degrees with respect to a plurality of leg portions 23 </ b> A to 23 </ b> D (in this drawing, bent toward the front side of the sheet). And the plate member 24 (24A, 24B) is attached to the surface of leg part 23A-23D by the side where the base part 22 was bent.

  The plate member 24 (24A, 24B) is positioned above (on the pedestal portion 22 side) the positive electrode current collector 7 of the electrode body 3 when the positive electrode current collector terminal 11 is assembled to the electrode body 3. Attached to the positive electrode current collector terminal 11. Specifically, the plate member 24A extends from the leg portion 23B toward the leg portion 23A adjacent to the outside thereof, and is attached to the leg portion 23B by the joint portion 29 so as to be applied to the leg portion 23A. The plate member 24B extends from the leg portion 23C toward the leg portion 23D adjacent to the outside thereof, and is attached to the leg portion 23C by the joint portion 29 so as to be applied to the leg portion 23D. The plate member 27 is similarly attached to the negative electrode current collecting terminal 12.

  Referring again to FIG. 8, in lid forming step S <b> 5, positive electrode external terminal 9, negative electrode external terminal 10, positive electrode current collector terminal 11, and negative electrode current collector terminal 12 are assembled to lid 21 of housing case 2.

  FIG. 17 is a diagram illustrating a state in which the positive electrode external terminal 9 and the negative electrode external terminal 10, and the positive electrode current collector terminal 11 and the negative electrode current collector terminal 12 are assembled to the lid 21 of the housing case 2. Referring to FIG. 17, positive external terminal 9 is assembled to one end of the upper surface of lid 21, and negative external terminal 10 is assembled to the other end of the upper surface of lid 21.

  Then, below the positive external terminal 9, the positive current collector terminal 11 is assembled to the lower surface of the lid 21, and the positive external terminal 9 and the pedestal portion 22 of the positive current collector terminal 11 are electrically connected through a hole formed in the lid 21. Connected. Similarly, below the negative electrode external terminal 10, the negative electrode current collector terminal 12 is assembled to the lower surface of the lid 21, and the negative electrode external terminal 10 and the base portion 25 of the negative electrode current collector terminal 12 are connected through a hole formed in the lid 21. Electrically connected.

  Referring to FIG. 8 again, in the lid / electrode assembly assembling step S6, the lid 21, the positive external terminal 9, the negative external terminal 10, the positive current collecting terminal 11, and the negative current collecting assembled in the lid forming step S5. The terminal 12 is assembled to the electrode body 3.

  FIG. 18 is a diagram illustrating a state in which the lid 21 of the housing case 2, the positive electrode current collector terminal 11, and the negative electrode current collector terminal 12 are assembled to the electrode body 3. FIG. 19 is a view showing a state in which the positive electrode current collecting terminal 11 is assembled to the electrode body 3.

  With reference to FIGS. 18 and 19, the lid 21, the positive electrode current collector terminal 11, and the negative electrode current collector terminal 12 are assembled to the electrode body 3 from above the electrode body 3. At this time, the positive electrode current collector terminal 11 is assembled to the electrode body 3 so that the positive electrode current collector 7 is inserted into the slit of the leg portion 23 of the positive electrode current collector terminal 11. Although not shown, the negative electrode current collector terminal 12 is assembled to the electrode body 3 so that the negative electrode current collector 8 is inserted into the slit of the leg portion 26 of the negative electrode current collector terminal 12 also on the negative electrode side. .

  Referring to FIG. 8 again, in the current collecting terminal pressurizing step S7, the leg portion 23 of the positive electrode current collecting terminal 11 is pressurized from both side surfaces, and the gap between the leg portion 23 and the positive electrode current collector 7 is narrowed. Similarly, the leg part 26 of the negative electrode current collector terminal 12 is also pressurized from both side surfaces, and the gap between the leg part 26 and the negative electrode current collector 8 is narrowed.

  In the current collector terminal welding step S8, the leg portion 23 of the positive electrode current collector terminal 11 and the positive electrode current collector 7 are welded, and the leg portion 26 of the negative electrode current collector terminal 12 and the negative electrode current collector 8 are welded.

  FIG. 20 is a perspective view showing a state in which the positive electrode current collector 7 is welded to the leg portion 23 of the positive electrode current collector terminal 11. 21 to 23 are cross-sectional views showing a state in which the positive electrode current collector 7 is welded to the leg portion 23 of the positive electrode current collector terminal 11.

  Referring to FIGS. 20 to 23, the tip of positive electrode current collector 7 protrudes from a slit between leg portions 23A to 23D. By irradiating the tip of the positive electrode current collector 7 with the laser beam LB in a state where the leg parts 23A to 23D are pressurized from both sides in the current collecting terminal pressurizing step S7, the positive electrode current collector 7 becomes the leg part 23A. Welded to ~ 23D.

  In this embodiment, the plate members 24 (24A, 24B) are provided on the leg portions 23A to 23D, so that the leg portions are twisted when the legs 23A to 23D are pressed in the collector terminal pressurizing step S7. Is suppressed, and the disorder of the arrangement of the leg portions 23A to 23D is suppressed. Thereby, in current collection terminal pressurization process S7, the positive electrode current collector 7 can be firmly sandwiched between the leg portions 23A to 23D without a gap, and the leg portions 23A to 23D are connected to the positive electrode current collector in the welded portion 28. The body 7 is welded well.

  Referring again to FIG. 8, in the housing step S <b> 9, the electrode body 3, the lid 21 assembled to the electrode body 3, the positive electrode current collecting terminal 11, and the negative electrode current collecting terminal 12 are attached to the case body 20 of the housing case 2. Be contained. The lid 21 is disposed so as to close the opening of the case body 20.

  In the lid welding step S10, the outer peripheral edge portion of the lid 21 and the opening edge portion of the case body 20 are welded. In the injection step S11, the electrolytic solution 6 is injected into the housing case 2 from an injection port (not shown) of the lid 21. And in sealing process S12, said inlet is obstruct | occluded with the sealing member. Thereby, the sealed battery 1 shown in FIG. 1 is completed.

<Description of Comparative Example>
Hereinafter, a comparative example in which the plate members 24 and 27 are not provided on the positive electrode current collector terminal 11 and the negative electrode current collector terminal 12 will be briefly described.

  FIG. 24 is a plan view of the positive electrode current collector terminal when the positive electrode current collector terminal in the comparative example is viewed from the electrode body side. FIG. 25 is a plan view of the positive electrode current collector terminal in the comparative example when viewed in the Y direction. Referring to FIGS. 24 and 25, the positive electrode current collecting terminal in the comparative example is not provided with the plate member 24 in the embodiment. In the current collecting terminal pressurizing step, when the leg portion of the positive current collecting terminal is pressurized from both side surfaces, the outer leg portions 23A and 23D are deformed in the load direction.

  26 and 27 are cross-sectional views schematically showing the leg portion of the positive electrode current collector terminal during the current collector terminal pressurizing step in the comparative example. FIG. 26 shows the arrangement of the leg portions 23A to 23D when the slits between the leg portions 23A and 23B and the slits between the leg portions 23C and 23D are closed by applying a clamping force to the leg portions 23A to 23D. FIG. 27 shows the arrangement of the leg portions 23A to 23D when the slit between the leg portions 23B and 23C is also closed by further applying a clamping force. In practice, since the positive electrode current collector is sandwiched between the leg portions 23A to 23D, the slit is not completely closed as shown in FIGS.

  Referring to FIG. 25 as well as FIG. 26 and FIG. 27, the positive electrode current collector terminal in the comparative example is not provided with the plate member 24 in the embodiment of the present disclosure. When an external force (clamping force) in the Z direction is applied to .about.23D, the legs 23A and 23D are twisted from the base of the slit (FIG. 25), and the slits of the legs 23A and 23D (the legs 23B of the legs 23A and the legs 23B) The adjacent side and the side adjacent to the leg portion 23C of the leg portion 23D) are deformed in the X direction (the direction of the electrode body).

  Then, when an external force (clamping force) is further applied to the legs 23A to 23D to such an extent that the slit between the legs 23B and 23C is also closed (FIG. 27), the base of the slit between the legs 23B and 23C is deformed in the Y direction. As a result, the leg portions 23B and 23C are deformed in the −X direction (the direction opposite to the leg portions 23A and 23D).

  Thus, in the comparative example, when the leg portions 23A to 23D are pressed from both sides in the current collecting terminal pressurizing step, the outer leg portions 23A and 23D are twisted and the inner leg portions 23B and 23C are also deformed. For this reason, the arrangement of the leg portions 23 </ b> A to 23 </ b> D is disturbed in the current collecting terminal pressurizing step, and a gap remains between the leg portions 23 </ b> A to 23 </ b> D and the positive electrode current collector 7. In this state, when the leg portions 23A to 23D are welded to the positive electrode current collector in the current collector terminal welding process, laser light is emitted from the gap, or metal pieces generated by welding are scattered to the electrode body side. There is a risk.

  FIG. 28 is a cross-sectional view showing how the positive electrode current collector 7 is welded to the leg portion 23 of the positive electrode current collector terminal in the comparative example. Referring to FIG. 28, the positive electrode current collector 7 is welded to the leg portions 23A to 23D by irradiating the front end portion of the positive electrode current collector 7 protruding from the slit between the leg portions 23A to 23D with the laser beam LB. The

  In the comparative example, since the arrangement of the leg portions 23 </ b> A to 23 </ b> D is disturbed, there may be a gap between the leg portions 23 </ b> A to 23 </ b> D and the positive electrode current collector 7. Then, there is a possibility that the laser beam LB may be lost from the gap, or, as shown in the figure, metal pieces generated by welding may be scattered on the electrode body side (current collector side).

  On the other hand, in the sealed battery 1 according to this embodiment, as shown in FIGS. 2 to 7, while allowing the movement of the leg 23A (23D) in the direction of the leg 23B (23C), A plate member 24A (24B) that restricts the movement of the leg 23A (23D) in the direction of the electrode body 3 is provided. Thereby, in the current collector terminal pressurizing step S7, when the positive electrode current collector 7 is sandwiched between the slits between the leg portions 23A to 23D, the arrangement of the leg portions 23A to 23D as shown in FIGS. Is prevented, and the positive electrode current collector 7 can be firmly sandwiched between the leg portions 23A to 23D without any gap. As a result, good welding can be performed, and laser beam LB can be prevented from being released from the gap during welding, and metal pieces generated due to welding can be prevented from scattering to the electrode body 3 side.

  FIG. 29 is a diagram illustrating an evaluation result of welding between the current collector terminal and the current collector in the sealed battery 1 according to the embodiment of the present disclosure and the sealed battery of the comparative example. In the evaluation of welding, the welded portion was disassembled, the separator was damaged and damaged by the laser beam loss, and the presence or absence of the melt was confirmed. About the damage damage of a separator, it confirmed with the magnifier whether the transparent part by heat had arisen in the separator. About the scattering of the molten material, the presence or absence of the scattered material on the back side of the current collecting terminal was confirmed with a magnifying glass. About evaluation, what did not have the damage damage of a separator and was not scattered of a melt was made good (evaluation OK).

  Referring to FIG. 29, regarding the sealed battery of the comparative example, at least one of damage damage to the separator and scattering of the melt was confirmed in 5 samples out of 10 samples. In the current collecting terminal pressurizing step, the arrangement disorder of the leg portions of the current collecting terminal occurred, so that the laser light was lost from the gap and the metal pieces generated due to welding were scattered.

  On the other hand, for sealed battery 1 according to the embodiment of the present disclosure, all 10 samples were non-defective products. In the sealed battery 1, since the plate members 24 and 27 are provided on the positive electrode current collector terminal 11 and the negative electrode current collector terminal 12, respectively, the disorder of the arrangement of the legs of the current collector terminal is suppressed in the current collector terminal pressurizing step. The As a result, the laser beam is prevented from coming out from the gap, and the damage to the separator and the scattering of the melt accompanying the welding into the battery are suppressed.

  As described above, according to the embodiment of the present disclosure, the positive electrode current collector terminal 11 and the negative electrode current collector terminal 12 can be well welded to the electrode body 3 (the positive electrode current collector 7 and the negative electrode current collector 8). And the influence on the electrode body 3 in the case of welding can be suppressed.

[Modification 1]
30 is a plan view of the positive electrode current collector terminal when the positive electrode current collector terminal in Modification 1 of the embodiment is viewed from the −X direction (from the electrode body 3 side). FIG. 31 is a plan view of FIG. It is sectional drawing along XXXI-XXXI. In addition, the structure of a negative electrode current collection terminal is the same as that of a positive electrode current collection terminal, and below, a positive electrode current collection terminal is demonstrated typically.

  With reference to FIGS. 30 and 31, in Modification 1, the positive electrode current collecting terminal 11 </ b> A is the same as the plate member 24 (24 </ b> A, 24 </ b> A, 24B) includes a plate member 40 (40A, 40B).

  The plate member 40A is different from the plate member 24A in that a stepped portion 41A is formed at a portion of the leg portion 23A. The step portion 41A is formed to have a gap with the leg portion 23A. The plate member 40B is also different from the plate member 24B in that a stepped portion 41B is formed in a portion related to the leg portion 23D. The step portion 41B is formed to have a gap with the leg portion 23D.

  Regarding the gap between the stepped portion 41A and the leg portion 23A and the gap between the stepped portion 41B and the leg portion 23D, for example, the leg portion at the time of pressurizing the leg portions 23A to 23D in the collector terminal pressurizing step S7 It can be determined based on the allowable range of twist of 23A and 23D.

  By forming such stepped portions 41A and 41B, the leg portion 23A (23D) becomes the plate member 40A (40B) at the initial stage of pressurization to the leg portions 23A to 23D in the collector terminal pressurizing step S7. Do not contact with. Thereby, friction does not generate | occur | produce between leg part 23A (23D) and plate member 40A (40B), and the load to leg part 23A-23D and a deformation | transformation of leg part 23A-23D are reduced.

[Modification 2]
32 is a plan view of the positive electrode current collector terminal when the positive electrode current collector terminal in Modification 2 of the embodiment is viewed from the −X direction (from the electrode body 3 side). FIG. 33 is a plan view of FIG. It is sectional drawing along XXXIII-XXXIII. In addition, the structure of a negative electrode current collection terminal is the same as that of a positive electrode current collection terminal, and below, a positive electrode current collection terminal is demonstrated typically.

  Referring to FIGS. 32 and 33, in Modification 2, positive electrode current collecting terminal 11B is connected to plate members 24A and 24B in positive electrode current collecting terminal 11 in the above-described embodiment shown in FIGS. Instead, plate-like portions 45A and 45B are included.

  The plate-like portions 45A and 45B are integrally formed with the leg portions 23B and 23C, respectively, in the portion where the plate members 24A and 24B of the positive electrode current collecting terminal 11 shown in FIGS. 3 and 4 are attached.

  The plate-like portion 45A is formed so as to extend from the leg portion 23B toward the leg portion 23A adjacent to the outside of the leg portion 23B and to cover the leg portion 23A. The plate-like portion 45B extends from the leg portion 23C toward the leg portion 23D adjacent to the outside thereof and is formed so as to cover the leg portion 23D.

  Although not particularly illustrated, a step portion is provided in the portion of the plate-like portion 45A on the leg portion 23A so as to have a gap with the leg portion 23A as in the first modification, and the leg portion of the plate-like portion 45B is provided. In the portion related to 23D, a step portion may be provided so as to have a gap with the leg portion 23D.

[Modification 3]
FIG. 34 is a plan view of the positive electrode current collector terminal when the positive electrode current collector terminal in Modification 3 of the embodiment is viewed from the −X direction (from the electrode body 3 side). FIG. 35 is a plan view of the modification 3 in which the positive electrode current collecting terminal attached to the electrode body 3 is viewed in the X direction.

  34 and 35, in the above-described embodiment, as shown in FIGS. 2 and 3, the plate members 24A and 24B are located above the positive electrode current collector 7 of the electrode body 3 (the pedestal portion). The plate members 24A and 24B are provided below the positive electrode current collector 7 of the electrode body 3 (on the side far from the pedestal portion 22) as shown in the figure. Also good.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  DESCRIPTION OF SYMBOLS 1 Sealed battery, 2 Containment case, 3 Electrode body, 4, 5 End surface, 6 Electrolyte, 7 Positive electrode collector, 8 Negative electrode collector, 9 Positive external terminal, 10 Negative external terminal, 11, 11A, 11B Positive electrode Current collecting terminal, 12 Negative current collecting terminal, 20 Case body, 21 Lid, 22, 25 Base part, 23, 23A to 23D, 26 Leg part, 24, 24A, 24B, 27, 40A, 40B Plate member, 28 Welded part , 29 Joint part, 30 Positive electrode sheet, 31, 34 Active material mixture layer, 32, 35 Uncoated foil part, 33 Negative electrode sheet, 41A, 41B Step part, 45A, 45B Plate-like part, 50, 51 Ingredients.

Claims (1)

An electrode body that includes a plurality of stacked electrode plates, and a current collector is formed on a side surface along the stacking direction of the plurality of electrode plates;
A current collector terminal welded to the current collector,
The current collecting terminal is
A pedestal,
A plurality of legs extending along the side surface at a distance from the pedestal,
The current collector is sandwiched between the plurality of legs and welded to the plurality of legs.
The current collecting terminal further includes:
The one of the plurality of legs is provided on one leg and extends from the one leg toward another leg adjacent to the outside of the one leg. A sealed battery including a member configured to regulate movement of the other leg in the direction of the electrode body while allowing movement in the direction of the leg.

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