JP2009277593A - Method and device of manufacturing sealed battery, and sealed battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method and a manufacturing device of a sealed battery and the sealed battery, capable of preventing welding failure of a sealing body and an armoring can, by restraining a warp of the sealing body. <P>SOLUTION: This manufacturing method includes a process of forming a fitting body 9 by fitting the sealing body 2 to an opening of the armoring can 1, a temporary fastening welding process of welding a part of the sealing body 2 to the armoring can 1 in a state of pressing the fitting body 9 from the sealing body 2 side, and a permanent welding process of welding the outer periphery of the sealing body 2 to the armoring can 1. With this constitution, seam welding in permanent welding is also improved by improving a fitting state of the sealing body 2 and the armoring can 1 by temporary fastening welding before permanent welding. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sealed battery in which an outer can is sealed with a sealing body, a manufacturing method thereof, and a manufacturing apparatus.

  In recent years, small and light electronic devices such as mobile phones and mobile devices have become widespread. As a battery used in these electronic devices, a rectangular sealed battery is known. FIG. 7 shows a perspective view of an example of a conventional sealed battery. As shown in FIG. 7A, the sealed battery 100 is formed by sealing the opening of a bottomed cylindrical outer can 101 containing an electrode body (not shown) with a sealing body 102.

  Sealing of the outer can 101 with the sealing body 102 is performed by seam welding the seam 103 of the outer can 101 and the sealing body 102 over the entire circumference with the sealing body 102 fitted in the opening of the outer can 101. .

For example, Patent Document 1 below describes an example in which a battery lid (sealing body) made of SUS404 is fitted to the inner peripheral surface of an opening of a steel sheet outer can and seam-welded by laser. Patent Document 2 describes an example in which the upper surface of a can (outer can) is closed with a lid (sealing body).
JP-A-9-288999 JP-A-9-245751

  However, in the rectangular sealed battery, the sealing body 102 is horizontally long, and when the sealing body 102 is attached to the outer can 101, the sealing body 102 and the outer can 101 do not fit in the center due to warpage of the sealing body 102. It may be enough. This problem is likely to occur when the battery width is increased in response to a request for higher capacity of the battery. This is because the length of the sealing body 102 becomes longer as the battery width increases, and the warping of the sealing body 102 is likely to occur.

  FIG. 7B is a perspective view showing an example in the case where the fitting between the sealing body 102 and the outer can 101 is insufficient. As shown in the figure, the sealing body 102 is fitted to the outer can 101 at both ends. However, due to the warping of the sealing body 102, the sealing body 102 is not in engagement with the outer can 101 at the center. This is caused by the spring action of the positive electrode current collecting lead and the negative electrode current collecting lead (not shown) connected to the lower part of the sealing body 102 in addition to the sealing body 102 being horizontally long.

  In such a state, it is impossible to perform seam welding over the entire circumference of the sealing body 102, resulting in poor welding. On the other hand, in Patent Documents 1 and 2, there is no description of a problem due to warping with respect to the cover material corresponding to the sealing body 102 in FIG.

  The present invention solves the conventional problems as described above, and suppresses warpage of the sealing body, thereby preventing a welding failure between the sealing body and the outer can. It aims at providing a sealed type battery.

  In order to achieve the above object, the sealed battery manufacturing method of the present invention includes a step of fitting a sealing body into an opening of an outer can and forming a fitting body, and a state in which the fitting body is pressed from the sealing body side. Thus, a temporary fixing welding process for welding a part of the sealing body to the outer can and a main welding process for welding the outer periphery of the sealing body to the outer can are provided.

  The sealed battery manufacturing apparatus of the present invention is a sealed battery manufacturing apparatus in which a sealing body is fitted into an opening of an outer can, and the fitting body of the outer can and the sealing body is connected to the sealing body from the sealing body side. An upper die for pressing and a welding machine for welding the sealing body to the outer can are provided.

  The sealed battery of the present invention is a sealed battery in which a sealing body is fitted to an opening of an outer can, and the outer periphery of the sealing body is welded to the outer can. It is characterized in that there is a welded part overlapping the welded part.

  ADVANTAGE OF THE INVENTION According to this invention, the curvature of a sealing body can be suppressed and the welding defect with a sealing body and an exterior can can be prevented.

  According to the method for manufacturing a sealed battery of the present invention, since the fitting state between the sealing body and the outer can can be improved by temporary fixing before the main welding, the seam welding in the main welding is also improved.

  According to the sealed battery manufacturing apparatus of the present invention, it is possible to improve the fitting state between the sealing body and the outer can by suppressing warping of the sealing body.

  Since the sealed battery of the present invention is temporarily welded before the sealing body is fully welded. The sealing body is well welded.

  In the sealed battery manufacturing method of the present invention, it is preferable that the welding in the temporary fixing welding process is performed in a state where the fitting body is pressed from the sealing body side and both side surfaces of the outer can are pressed. According to this structure, the fitting state of a sealing body and an exterior can becomes better.

  Moreover, in the said main welding process, it is preferable to weld the perimeter of the said sealing body to the said exterior can, overlapping and welding to the welding location in the said temporary fixing welding process.

  The sealed battery manufacturing apparatus of the present invention preferably further includes a horizontal mold that presses both side surfaces of the outer can. According to this structure, the fitting state of a sealing body and an exterior can becomes better.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The sealed battery according to the following embodiment is, for example, a rectangular lithium ion battery, and is used for a mobile phone, a mobile device, or the like.

  FIG. 1 is a perspective view showing a state in which a sealing body is fitted into the opening of the outer can. FIG. 1A is a perspective view showing a state before the sealing body 2 is fitted into the opening of the outer can 1, and FIG. 1B is a state where the opening of the outer can 1 and the sealing body 2 are fitted. FIG.

  The outer can 1 is a bottomed cylindrical body in which a substantially rectangular opening is formed at the upper end. The outer can 1 is formed, for example, by deep drawing a thin plate of aluminum or aluminum alloy. An electrode body 3 is built in the outer can 1. From the electrode body 3, a thin plate-like positive electrode current collecting lead 4 and a negative electrode current collecting lead 5 are led out.

  The sealing body 2 is a horizontally long member obtained by press-molding a thin plate of aluminum or an aluminum alloy, for example. As shown in FIG. 1B, the negative electrode terminal 6 is provided on the surface of the sealing body 2. Although not shown in the figure, an explosion-proof recess may be provided on the surface of the sealing body 2 in some cases.

  As shown in FIG. 1A, a lead body 7 connected to the negative electrode terminal 6 (FIG. 1B) is provided on the back surface of the sealing body 2. An insulator (not shown) is interposed between the lead body 7 and the back surface of the sealing body 2. The sealing body 2 is formed with an injection hole 8 for injecting the electrolytic solution into the outer can 1.

  In the state of FIG. 1A, the back surface of the sealing body 2 and the positive electrode current collector lead 4 are welded, and the lead body 7 and the negative electrode current collector lead 5 are welded. For these weldings, for example, laser welding or resistance welding is used. From the state of FIG. 1A, the outer periphery of the sealing body 2 is fitted to the inner peripheral surface of the opening of the outer can 1 while bending the positive electrode current collecting lead 4 and the negative electrode current collecting lead 5.

  In the fitting body 9 between the outer can 1 and the sealing body 2 shown in FIG. 1B, warpage occurs in the sealing body 2, and the fitting is insufficient in the vicinity of the negative electrode terminal 6. The warp of the sealing body 2 tends to increase as the length of the sealing body 2 that is a horizontally long member increases. The warpage of the sealing body 2 is also caused by the spring action of the bent positive electrode current collecting lead 4 and negative electrode current collecting lead 5.

  According to this Embodiment, even if it is the fitting body 9 with which fitting with the exterior can 1 and the sealing body 2 is inadequate, the welding defect of the sealing body 2 can be prevented. This will be specifically described below.

  FIG. 2 is a perspective view showing a temporary fixing welding process. As the fitting body 9, a fitting body with insufficient fitting between the outer can 1 and the sealing body 2 shown in FIG. In the temporary fixing welding process, a sealed battery manufacturing apparatus including a temporary fixing mechanism is used. Details of this apparatus will be described later with reference to FIG. In FIG. 2, a pair of horizontal mold 10 and upper mold 11 are components of the temporary fixing mechanism. A pair of horizontal molds 10 press both side surfaces of the outer can 1, and the upper mold 11 presses the sealing body 2.

  In FIG. 2, the horizontal mold 10 and the upper mold 11 are illustrated as examples of plate-like members, but are not limited to plate-like members, and may be those provided with a pressing surface having a shape that matches the target surface to be pressed. Good. In FIG. 2, the upper mold 11 may have a size corresponding to the entire length of the sealing body 2, and the horizontal mold 10 may have a size corresponding to the entire width of the side surface of the outer can 1.

  3A and 3B are diagrams showing a temporarily fixed state of the fitting body 9, in which FIG. 3A is a side view and FIG. 3B is a plan view. As shown in FIG. 3A, by pressing the both side surfaces of the outer can 1 with a pair of horizontal molds 10, swelling of both side surfaces can be suppressed. By pressing the sealing body 2 with the upper mold 11, it is possible to suppress warping of the sealing body 2 as shown in FIG. When the position of the front end surface of the negative electrode terminal 6 (FIG. 1B) is higher than the upper end surface of the outer can 1, a recess may be provided on the back surface of the upper mold 11.

  As shown in FIG. 3B, the upper mold 11 includes four through holes 12a-12d. The sealing body 2 can be welded to the exterior can 1 by irradiating a portion of the joint 13 between the exterior can 1 and the sealing body 2 corresponding to the through holes 12a to 12d with laser light.

  FIG. 4 is a perspective view showing a temporary fixing welding process, FIG. 4A is a perspective view showing a state during welding, and FIG. 4B is a perspective view showing a state after welding. In the state of FIG. 4A, the laser beam is irradiated from the laser welding machine 20 to the portion corresponding to the through hole 12 a in the joint 13 between the outer can 1 and the sealing body 2. This completes welding at one location.

  Each time welding at one place is completed, the laser welding machine 20 is moved to a different through hole position, and welding is performed again. In this way, a total of four temporary fixing welds are completed. As a result, as shown in FIG. 4B, four welded nuggets 14 a-14 d are formed at the joint 13 between the outer can 1 and the sealing body 2.

  As described above, the temporary fixing welding is performed in a state in which the warpage of the sealing body 2 is suppressed while suppressing the swelling of both side surfaces of the outer can 1. For this reason, even if the fitting state between the sealing body 2 and the outer can 1 is insufficient before temporary fixing welding, the fitting state between the sealing body 2 and the outer can 1 is good after temporary fixing welding. It has become.

  In addition, a welding location is not restricted to 4 places, What is necessary is just to determine suitably as needed. For example, it is good also considering a welding location as each one of two sides which the sealing body 2 opposes, and a total of two locations. In this case, if each welding location is not arranged on the line in the thickness direction (Y direction) of the outer can 1 but is shifted in the width direction (X direction) of the outer can 1, The stop is more reliable. In the example of FIG. 4A, this is the position of the through holes 12a and 12c or the position of the through holes 12b and 12d.

  Moreover, although the upper mold | type 11 demonstrated in the example provided with the four through-holes 12a-12d corresponding to the welding location, another shape may be sufficient if a welding location can be exposed. For example, the shape corresponding to the welded portion may be provided with a notch.

  Moreover, the method of temporary fixing welding is not limited to laser welding, and may be resistance welding or an adhesive.

  Moreover, in the example of FIG.4 (b), although the four welding nuggets 14a-14d demonstrated by the example of a dotted | punctate form, a linear form may be sufficient.

  Moreover, although demonstrated by the example of temporary fixing welding using both the horizontal mold | type 10 and the upper mold | type 11, when the swelling of the both sides | surfaces of the outer can 1 is hard to produce at the time of fitting with the outer can 1 and the sealing body 2. FIG. May omit the pressing by the horizontal mold 10.

  FIG. 5 is a schematic diagram of a sealed battery manufacturing apparatus according to an embodiment of the present invention. The sealed battery manufacturing apparatus 30 shown in the figure includes a pair of horizontal mold 10 and upper mold 11 shown in FIG. The movable mechanism of the horizontal mold 10 and the upper mold 11 may be appropriately designed using a normal mechanism. For example, the pressing by the pair of horizontal molds 10 may use a cylinder mechanism or a cam mechanism. The pressing by the upper mold 11 may be performed, for example, by attaching the upper mold 11 to the arm and rotating the upper mold 11 integrally with the arm.

  The arm 21 supports the laser welding machine 20. The arm 21 is mounted on the table 22. If the arm 21 is moved in the X direction (perpendicular to the paper surface), the laser welding machine 20 can be moved in the width direction of the outer can 1 (X direction in FIG. 4A). For this movement, for example, the arm 21 may be connected to a rod of a cylinder mechanism having a rod that expands and contracts in the X direction.

  If the arm 21 is moved in the Y direction, the laser welding machine 20 can be moved in the thickness direction of the outer can 1 (Y direction in FIG. 4A). In the example of FIG. 5, the table 22 can be reciprocated in the Y direction by rotating the cam 23 and reciprocating the tip of the cam 23. Thus, the arm 21 reciprocates in the Y direction, and the laser welding machine 20 integrated with the arm 21 can reciprocate in the Y direction.

  As described above, according to the sealed battery manufacturing apparatus shown in FIG. 5, the laser welding machine 20 can be moved in the X direction and the Y direction. Thereby, in the example of Fig.4 (a), welding can be performed in the position of each through-hole, moving the laser welding machine 20 to the position of the adjacent through-hole.

  In FIG. 5, the fitting body 9 is placed on the tray 25 during temporary fixing welding. The tray 25 is shown in a sectional view to show the internal state. The tray 25 is placed on the conveyor 26. When the temporary fixing welding of one fitting body 9 is completed, the tray 25 is conveyed to the conveyor 26 and the next temporary fixing welding of the fitting body 9 is performed.

  In addition, although the manufacturing apparatus of the sealed type battery shown in FIG. 5 demonstrated in the example provided with both the horizontal mold | type 10 and the upper mold | type 11, it targets the sealed battery which cannot produce the swelling of the both sides | surfaces of the armored can 1 as an object. In this case, a configuration in which the horizontal mold 10 is omitted can be considered.

  FIG. 6 is a perspective view showing seam welding of the fitting body 9. When the temporary fixing welding of the fitting body 9 is completed, the process shifts to the main welding of the fitting body 9. In the main welding, a dedicated welding machine is used for the main welding. In the main welding, as shown in FIG. 6, both side surfaces of the outer can 1 are pressed by a pair of horizontal molds 32. In this state, the seam 33 between the outer can 1 and the sealing body 2 is seam-welded over the entire circumference while being overlapped and welded to the welding location in the temporary fixing welding process by the laser welding machine 31.

  As described above, since the fitting state between the sealing body 2 and the outer can 1 is improved by temporary fixing before the main welding, the seam welding in the main welding is also improved.

  Since the sealing body 2 is temporarily fixed and welded, in the main welding, pressing of both side surfaces of the outer can 1 by the horizontal mold 32 may be omitted. When the horizontal mold 32 is used, the horizontal mold 32 may have a size corresponding to the entire width of the side surface of the outer can 1.

  After the seam welding is completed, an electrolytic solution is injected from the injection hole 8, and the injection hole 8 is sealed to complete a sealed battery.

  As described above, according to the present invention, it is possible to suppress warpage of the sealing body and prevent poor welding between the sealing body and the outer can. Therefore, the present invention is a sealed type used for, for example, a mobile phone or a mobile device. It is useful as a battery, its manufacturing method, and manufacturing apparatus.

It is a perspective view which shows a mode that a sealing body is fitted to the opening of the armored can which concerns on one embodiment of this invention, (a) A figure before fitting the sealing body 2 to the opening of the armored can 1 FIG. 4B is a perspective view showing a state in which the opening of the outer can 1 and the sealing body 2 are fitted. The perspective view which shows the temporary fix | stop process which concerns on one embodiment of this invention. It is a figure which shows the temporary fix | stop state of the fitting body which concerns on one embodiment of this invention, (a) A figure is a side view, (b) A figure is a top view. It is a perspective view which shows the temporary fixing welding process which concerns on one embodiment of this invention, (a) A figure is a perspective view which shows the state during welding, (b) A perspective view which shows the state after welding. BRIEF DESCRIPTION OF THE DRAWINGS Schematic of the manufacturing apparatus of the sealed battery which concerns on one embodiment of this invention. The perspective view which shows the seam welding of the fitting body which concerns on one embodiment of this invention. (A) The figure is a perspective view of an example of the conventional sealed battery, (b) The figure is a perspective view showing an example when the fitting between the sealing body and the outer can is insufficient.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exterior can 2 Sealing body 9 Fitting body 10 Horizontal type 11 Upper type 12a, 12b, 12c, 12d Through-hole 13 Seam part 14a, 14b, 14c, 14d Welding nugget 20,31 Welding machine 30 Manufacturing apparatus of sealed battery

Claims (6)

Forming a fitting body by fitting a sealing body into the opening of the outer can;
In a state where the fitting body is pressed from the sealing body side, a temporary fixing welding step of welding a part of the sealing body to the exterior can;
And a main welding step of welding the outer periphery of the sealing body to the outer can.   The sealed battery manufacturing method according to claim 1, wherein the welding in the temporary fixing welding step is performed in a state where the fitting body is pressed from the sealing body side and both side surfaces of the outer can are pressed.   3. The method for manufacturing a sealed battery according to claim 1, wherein, in the main welding step, the entire circumference of the sealing body is welded to the outer can while being overlapped and welded to a welding location in the temporary fixing welding step. An apparatus for manufacturing a sealed battery in which a sealing body is fitted to an opening of an outer can,
An upper mold that presses the fitting body between the outer can and the sealing body from the sealing body side;
An apparatus for manufacturing a sealed battery, comprising: a welding machine for welding the sealing body to the outer can.   The manufacturing apparatus of the sealed battery of Claim 4 further equipped with the horizontal type which presses the both sides | surfaces of the said exterior can. A sealed battery in which a sealing body is fitted to the opening of an outer can,
The outer periphery of the sealing body is welded to the outer can,
The sealed battery according to claim 1, wherein the welded area includes a welded portion that is overlapped with a place once welded.

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