JP2019110024A - Manufacturing method for battery - Google Patents

Abstract

To provide a manufacturing method for a battery capable of performing satisfactory laser sealing.SOLUTION: A manufacturing method for a battery is provided for sealing an opening of a case in which an electrolyte is accommodated, with a sealing plate. The manufacturing method for the battery includes the steps of: fitting a rising part which protrudes closer to a top face of the sealing plate at an outer edge of the sealing plate, to an inner periphery of the opening of the case; forming a temporary fixing melting part for temporarily fixing the sealing plate to the case by melting a sidewall of the case and the rising part by irradiating a region where the case and the rising part are fitted, with a first laser beam in a side face direction of the case; and forming a seam melting part for welding an opening end of the case and an end of the rising part at a position separated from the temporary fixing melting part by melting the opening end of the case and the end of the rising part by irradiating the ends with a second laser beam.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method of manufacturing a battery, and more particularly to a method of sealing an opening of a case by welding an opening end of the case and an outer peripheral end of a sealing plate.

  In assembling a cylindrical primary battery, a sealing plate having an annular rising portion protruding outward of the case is fitted to the circumference of the opening of the cylindrical case at the outer peripheral edge, and the open end of the case and the annular rising A laser sealing method and a laser sealing battery for laser welding with an end portion of a part are known (see, for example, Patent Document 1). FIG. 4 is a view showing a laser sealed battery described in Patent Document 1. As shown in FIG.

  In FIG. 4, a sealing plate 103 having an annular rising portion that protrudes outward of the case 102 is fitted to the cylindrical case 102 at the outer peripheral edge portion. Next, a laser beam (not shown) is irradiated from above the sealing plate 103 to the end face of the case 102 and the end face of the annular rising portion of the sealing plate 103 to form a laser welded portion 152.

  In addition, in the laser sealing of a rectangular battery, a plate-like sealing plate is fitted in the case opening, and a point-like temporary fixing portion is provided in advance at the interface between the case opening inside and the sealing plate, and then laser sealing is performed. FIG. 5A and FIG. 5B are views showing a method of welding a sealed container of a prismatic battery described in Patent Document 2. As shown in FIG.

  In FIG. 5A, the sealing plate 203 is fitted in the rectangular case 202 to form the temporarily fixed melting portion 251. Next, in FIG. 5B, a laser beam (without reference numeral) scans over the interface between the opening of the case 202 and the sealing plate 203, thereby forming a laser melting portion 252 and sealing the inside of the case 202.

JP-A-9-45296 JP-A-8-315790

  However, in the method described in Patent Document 1, there is a problem that a good laser sealing can not be realized due to the deformation of the outer shape of the case due to the thermal expansion.

  Moreover, in the method described in Patent Document 2, when the electrolytic solution is attached to the interface between the case and the sealing plate, there is a problem that a good sealing can not be realized.

  The present invention solves the above-mentioned conventional problems, and suppresses deformation of the case due to thermal strain at the time of laser welding, and enables good laser sealing even when the electrolyte adheres to the interface between the case and the sealing plate It is an object of the present invention to provide a method of manufacturing a battery.

In order to achieve the above object, a method of manufacturing a battery of one aspect of the present invention is
A method of manufacturing a battery, comprising: sealing an opening of a case for containing an electrolytic solution with a sealing plate,
Fitting a rising portion projecting on the upper surface side of the sealing plate at the outer edge of the sealing plate to the inner periphery of the opening of the case;
The sealing plate is made by irradiating the first laser beam from the side direction of the case to the region where the case and the rising portion are fitted, and melting the side wall of the case and the side wall of the rising portion. Forming a temporarily fixed melting portion temporarily fixed to the case,
By irradiating the second laser beam to the open end of the case and the end of the rising portion to melt it, the open end of the case and the rising portion are separated from the temporary fixing fusion portion. Forming a seam melt welded to the end,
including.

  As described above, according to the battery manufacturing method of the present invention, while suppressing the deformation of the case due to the thermal strain at the time of laser welding, even if the electrolytic solution is attached between the case and the sealing plate, a good laser sealing can be achieved. It is possible.

A schematic cross-sectional view of a cylindrical battery according to Embodiment 1 of the present invention A cross-sectional schematic view showing an example of the laser welding step in the first embodiment of the present invention A cross-sectional schematic view showing an example of the laser welding step in the first embodiment of the present invention A cross-sectional schematic view showing an example of a laser welding process in Embodiment 2 of the present invention A cross-sectional schematic view showing an example of a laser welding process in Embodiment 2 of the present invention The figure which shows the laser sealing battery described in patent document 1 The figure which shows the welding method of the sealed container of the square battery described in patent document 2 The figure which shows the welding method of the sealed container of the square battery described in patent document 2 The schematic diagram which shows the subject of the method of patent document 1 The schematic diagram which shows the subject of the method of patent document 2 The schematic diagram which shows the subject of the method of patent document 2

(Circumstances leading to the present invention)
In the method described in Patent Document 1, when the laser light is irradiated and the interface between the case and the sealing plate is scanned, the external shape of the case and the sealing plate is distorted by thermal expansion due to laser irradiation, and a good laser sealing is obtained. It may not be possible.

  In addition, as shown in FIG. 6, in the laser sealing in the state where the electrolytic solution 161 is attached to the bonding interface (in particular, the portion forming the gap between the case 102 and the sealing plate 103), the irradiation of the laser light 142 is performed. The electrolyte solution 161 is vaporized by heat due to the The vaporized electrolyte solution 162 is discharged out of the case 102.

  In the method described in Patent Document 2, as shown in FIG. 7A, in the temporarily fixed melting portion 251 provided in advance, the discharge of the vaporized electrolytic solution 262 to the outside is alienated, and from the vicinity of the irradiated portion of the laser light 242. It is discharged out of the case 202. Next, as shown in FIG. 7B, the welding between the case 202 and the sealing plate 203 may be inhibited by the discharge of the vaporized electrolytic solution 262, and a hole 254 may be formed in the molten portion 252. For this reason, there are cases where good bonding between the case 202 and the sealing plate 203 can not be performed.

  Therefore, the present inventor has arrived at the following invention in order to solve the above-mentioned problems.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1
FIG. 1 is a schematic cross-sectional view of a cylindrical battery 1 according to Embodiment 1 of the present invention. The X and Y directions in FIG. 1 indicate the lateral direction and the longitudinal direction of the cylindrical battery 1, respectively.

  As shown in FIG. 1, the cylindrical battery 1 includes a bottomed cylindrical case 2 and a sealing plate 3 welded to the case 2.

  The case 2 is, for example, a cylindrical case formed of metal such as SUS. The case 2 is formed in a bottomed cylindrical shape having an opening 21 at one end. The case 2 accommodates therein an electrode group 35 including a positive electrode, a separator, and a negative electrode, and an electrolytic solution 36.

  The sealing plate 3 includes a disk-shaped flange 31, a positive electrode terminal 32 disposed in a hole formed in the center of the flange 31, and a gasket 33 disposed between the flange 31 and the positive electrode terminal 32. .

  The flange 31 is formed of metal such as SUS. The flange 31 has a rising portion 37 projecting on the upper surface side of the sealing plate 3 at the outer edge. The rising portion 37 extends in the longitudinal direction (Y direction) of the cylindrical battery 1 and is annularly formed along the outer edge of the flange 31. The positive electrode terminal 32 is connected to the electrode group 35 via the positive electrode lead 34. The gasket 33 functions as an insulating member that insulates the flange 31 and the positive electrode terminal 32. The gasket 33 is made of, for example, a resin or the like.

  In the cylindrical battery 1, the sealing plate 3 is fitted to the inner periphery of the opening 21 of the case 2. Specifically, in the cylindrical battery 1, the inside of the opening 21 of the case 2 is in a state where the opening end 22 of the case 2 and the end of the rising portion 37 of the sealing plate 3 are flush with each other. The rising portion 37 of the sealing plate 3 is fitted around the periphery.

  In the first embodiment, in order to seal the case 2 and the sealing plate 3 for laser sealing, the seam melting portion 52 is formed after the temporarily fixed melting portion 51 is formed.

  The temporarily fixed melting portion 51 is welded to temporarily fix the sealing plate 3 in the opening 21 of the case 2 in a state where the inner periphery of the opening 21 of the case 2 and the rising portion 37 of the sealing plate 3 are fitted. Part of the The temporarily fixed melting portion 51 is formed by melting the side wall of the case 2 and the rising portion 37 of the sealing plate 3 by irradiating the laser light from the side direction (X direction) of the case 2.

  The temporarily fixed melting portion 51 is formed by irradiating a region where the case 2 and the rising portion 37 are fitted (hereinafter referred to as a “fitting region”) with laser light. The fitting region is a region where the inner periphery of the opening 21 of the case 2 is in contact with the rising portion 37 and is a region above the upper surface of the flange 31 of the sealing plate 3. Specifically, the temporary fixing is performed at a position shorter than the length of the rising portion 37 from the opening end 22 of the case 2 and the end of the rising portion 37 of the sealing plate 3 toward the bottom side of the cylindrical battery 1 Fused portion 51 is formed. For example, two or more temporary fixing and melting portions 51 are formed.

  The seam melting portion 52 is a portion for sealing and welding the case 2 and the sealing plate. The seam melting portion 52 is formed by irradiating a laser beam from the vertical direction (Y direction) of the case 2 to melt the opening end 22 of the case 2 and the end of the rising portion 37 of the sealing plate 3. The seam melting portion 52 is formed over the entire circumference of the open end portion 22 of the case 2 and the end portion of the rising portion 37 of the sealing plate 3.

  The manufacturing method of the battery 1 which concerns on this Embodiment 1 is demonstrated using FIG. 2A and 2B. FIGS. 2A and 2B are schematic cross-sectional views of the laser welding process for sealing the case 2 and the sealing plate 3 in the first embodiment. 2A and 2B are enlarged views of a portion of the cylindrical battery 1 of FIG. FIG. 2A is a schematic cross-sectional view for explaining an example of the step of forming the temporarily fixed melting portion 51 by the first laser beam 41, and FIG. 2B is the step of forming the seam melting portion 52 by the second laser beam 42. It is a cross-sectional schematic diagram for demonstrating an example.

  First, the rising portion 37 of the sealing plate 3 protruding outward of the case 2 is fitted to the inner periphery of the opening 21 of the case 2. Specifically, the rising portion 37 of the sealing plate 3 is fitted to the inner periphery of the opening 21 of the case 2 so that the end surface of the opening end 22 of the case 2 and the end surface of the end of the rising portion 37 are flush with each other. Match.

  Next, as shown in FIG. 2A, laser light is applied from the side direction (X direction) of the case 2 to the region (fitting region) where the inner side surface (inner wall) of the case 2 and the rising portion 37 are fitted. Temporary fixing and melting is performed using 41 (first laser light).

  In the first embodiment, the laser beam 41 is irradiated from the inside to the outside of the case 2 in the side direction of the case 2. That is, the laser beam 41 is irradiated toward the side wall of the rising portion 37. As a result, the side wall of the case 2 irradiated with the laser beam 41 and the side wall of the rising portion 37 melt to form the temporarily fixed melting portion 51. The temporarily fixed melting portion 51 is formed to penetrate the side wall of the case 2 and the side wall of the rising portion 37.

  After forming the temporarily fixed melting portion 51, as shown in FIG. 2B, a direction perpendicular to the upper surface of the case 2, ie, a direction (Y direction) at the end of the opening end 22 and the rising portion 37 of the case 2. The laser beam 42 (second laser beam) is irradiated. As a result, the opening end 22 of the case 2 and the end of the rising portion 37 melt to form the seam melting portion 52. The seam melting portion 52 is formed at a position separated from the temporarily fixed melting portion 51. Specifically, the seam melting portion 52 is formed at a position separated from the position where the temporary fixing melt portion 51 is formed on the upper side of the case 2. That is, the seam melting portion 52 is not connected to the temporarily fixed melting portion 51.

  As described above, in the first embodiment, after the temporary fixing and melting portion 51 is formed, the case 2 and the sealing plate 3 are integrated by forming the seam melting portion 52 at a position separated from the temporary fixing and melting portion 51. By making it possible to make a sealed battery.

  In the first embodiment, both of the laser beam 41 and the laser beam 42 use a single mode fiber laser (3 kW single mode YLS-3000-SM manufactured by IPG). The laser beam emitted from the fiber is collimated by a collimator lens (f 355 mm), and the laser beam collected by an fθ lens (255 mm) is scanned by using a galvano mirror to irradiate a predetermined position of the non-processed object Do.

  In the first embodiment, the distance from the fθ lens is such that the laser beam 42 has a spot diameter about 100 μm larger than the sum of the thickness of the opening end 22 of the case 2 and the thickness of the rising portion 37 of the sealing plate 3. Adjusted.

  The laser beam 42 has a spot diameter larger by about 100 μm than the sum of the thickness of the opening end 22 of the case 2 and the thickness of the end of the rising portion 37 of the sealing plate 3. It is possible to produce with high yield by allowing variations in shape and the like.

In the first embodiment, the laser beam 42 is irradiated with a continuous wave and seam welding is performed. The power density of the laser beam 42 is about 1.4 W / mm ² and the scanning speed is about 100 mm / s. As a result, the seam melting portion 52 formed by the laser beam 42 extends from the end of the opening end 22 and the end of the rising portion 37 of the case 2 toward the bottom of the case 2 in the state before the laser beam 42 is irradiated. It has a length of about 300 μm.

  In the first embodiment, a seam melting portion having a length of about 200 to 300 μm from the end of the open end 22 and the rising portion 37 of the case 2 in the state before irradiation of the laser light 42 toward the bottom of the case 2 Although 52 was formed, it is not limited to this. In order to further increase the sealing strength, the penetration depth may be increased and the seam melting portion 52 may be enlarged. For example, by increasing the power density of the laser beam 42 or decreasing the scanning speed, it is possible to make the penetration depth deeper and make the seam melting portion 52 larger.

  In the first embodiment, the laser beam 41 is processed at the focal position of the fθ lens. The combination of the focal length of the collimating lens and the fθ lens described above forms a spot diameter of about 20 μm according to optical calculation.

  In the first embodiment, for example, a pulsed laser of about 10 ms is used as the laser beam 41. Thus, a total of 18 spot-like temporarily fixed melting portions 51 penetrating from the outside of the case 2 to the inside of the sealing plate 3 were formed.

The power density of the laser beam 41 is, for example, 300 kW / mm ² . As a result, a keyhole (concave portion) can be formed in the area to which the laser beam 41 is irradiated, and the temporary fixing and melting portion 51 with a very small diameter can be formed. By forming the smaller temporary fixing and melting portion 51, the electrolytic solution 36 vaporized by the heat of the laser light irradiation can be easily released to the outside of the case 2, and the laser bonding failure can be further reduced.

  In the first embodiment, in order to form the seam melting portion 52 of the case 2 and the sealing plate 3, the opening end 22 of the case 2 and the end of the rising portion 37 of the sealing plate 3 are melted to be integrated. By making it possible, the case 2 and the sealing plate 3 can be sealed. As described above, since the laser beam 42 is irradiated to the opening end 22 of the case 2 and the end of the rising portion 37 of the sealing plate 3, the spot diameter may be adjusted to be large. Further, even if the spot diameter is small, the melting region may be expanded by swinging the laser spot, as long as an appropriate melting width and melting region can be secured.

  In the first embodiment, in order to form the temporarily fixed melting portion 51, a laser spot of high energy density is formed and irradiated to the fitting region. The temporarily fixed melting portion 51 is formed in a size that does not inhibit the release of the vaporized electrolyte 36 to the outside of the case 2. As the size of the temporarily fixed melting portion 51 is smaller, it does not hinder the discharge of the vaporized electrolyte 36 out of the case 2. For this reason, it is desirable to irradiate the laser spot of the energy density high enough to form a keyhole in the fitting area to form a minute temporary fixing fusion portion 51.

  Further, since the temporarily fixed melting portion 51 is formed penetrating the rising portion 37 of the sealing plate 3 and the side wall of the case 2, the shape of the temporarily fixed melting portion 51 is observed from the inside of the sealing plate 3 and the outside of the case 2 By doing this, it can be confirmed that the temporarily fixed melting portion 51 is formed reliably. That is, it can be confirmed by the temporary fixing and melting portion 51 that the sealing plate 3 is securely fixed to the case 2 with certainty.

  In the first embodiment, eighteen temporarily fixing and melting portions 51 are formed, but the number and interval of the temporarily fixing and melting portions 51 are not limited to these. The temporarily fixed melting portions 51 may have intervals and numbers that can suppress thermal deformation depending on the diameter of the cylindrical case 2. In addition, the gap may be locally narrowly arranged at a position where thermal deformation becomes larger, such as near the end point of seam welding of the laser light 42.

  In the first embodiment, the laser beam 41 is irradiated from the inside to the outside of the case 2 in the side direction (X direction) of the case 2. By irradiating the laser light 41 from the inside to the outside of the case 2, it is possible to reduce the adhesion of the sputter generated by the laser irradiation to the battery.

  The temporarily fixed melting portion 51 may be formed by irradiating the laser light 41 from the outside to the inside of the case 2 in the side direction (X direction) of the case 2. By irradiating the laser beam 41 from the outside of the side wall of the case 2, the temporarily fixed melting portion 51 can be easily formed.

  The laser beam 41 was irradiated from the end face of the open end 22 of the case 2 to a position of about 500 μm toward the bottom of the case 2. On the other hand, if the distance from the temporary fixing fusion portion 51 to the end face of the open end 22 of the case 2 is too long, the open end 22 of the case 2 is deformed by the influence of thermal expansion, and appropriate welding can not be performed. I am concerned. Therefore, the condition that the proper temporary fixing function is provided and the appropriate welding can be performed is in the region within 1.5 mm from the end face of the opening end 22 of the case 2 with the center (focus position) of the laser light for temporary fixing It is good to arrange.

  On the other hand, the seam melting portion 52 formed by the irradiation of the laser light 42 may reach the vicinity of the electrolytic solution 36 adhering to the interface between the case 2 and the sealing plate 3, and the electrolytic solution 36 may be vaporized. In this case, it is useful to form the temporarily fixed melting portion 51 at a position away from the end face of the open end 22 of the case 2 so as not to inhibit the vaporized electrolyte 36 from coming out of the case 2.

  In the first embodiment, for example, the depth of the seam melting portion 52 from the end face of the opening end portion 22 of the case 2 is 0.2 to 0.3 mm, and the temporarily fixed melting portion 51 is the opening end portion of the case 2 It is formed at a distance of 0.5 mm or more from the end face of 22. As a result, a good seam melting portion 52 can be formed without inhibiting the release of the vaporized electrolyte 36 out of the case 2. If the position of the temporarily fixed melting portion 51 is arranged at a position away from the end face of the open end portion 22 of the case 2, it is possible to suppress the inhibition of the discharge of the vaporized electrolytic solution 36. Depending on the depth of the seam melting portion 52 necessary for product characteristics and the size of the rising portion 37 projecting from the outer edge of the sealing plate 3, the temporary fixing and melting portion 51 may be disposed at a suitable position.

  In the first embodiment, the laser beam 41 is irradiated from the direction (X direction) perpendicular to the side wall surface of the case 2 but may be irradiated obliquely. By obliquely irradiating the laser beam 41, the shape of the temporarily fixed fusion portion 51 to be formed becomes an elliptical shape at the interface between the case 2 and the sealing plate 3. As a result, when the melting area of the temporarily fixed melting portion 51 is increased, the bonding strength is improved, and the thermal deformation can be further reduced.

  When the laser beam 41 is obliquely irradiated, it is preferable to irradiate the laser beam 41 from the inside of the rising portion 37 of the sealing plate 3 toward the outside of the case 2 and down to the bottom of the case 2 side. Thus, even when the laser beam 41 is obliquely irradiated, the temporarily fixed melting portion 51 formed at the interface between the case 2 and the sealing plate 3 is formed at a position away from the seam melting portion 52. For this reason, the laser melting failure can be reduced without preventing the discharge of the vaporized electrolytic solution 36 to the outside of the case 2.

  In the first embodiment, the present invention is applied to the cylindrical battery 1. However, the present invention may be applied to batteries of other shapes such as a square shape and a coin shape. For example, in the case of a square shape, the amount of thermal expansion differs between the long side and the short side forming the square, and a gap is easily formed between the case and the sealing body on the short side. It is sufficient to arrange the temporary fixing and melting portions more suitable for the shape, such as making the interval of the parts narrower than the distance between the temporary fixing and melting parts provided on the long side.

  Although an austenitic SUS is used for the case 2 and the sealing plate 3 in the first embodiment, a ferritic, martensitic, austenitic or ferritic (two-phase) SUS material may be used. Moreover, as a material which comprises case 2 and the sealing board 3, you may use iron type or aluminum type as a base material other than the material of SUS type | system | group. Since the amount of thermal expansion differs depending on the material, the size and / or number of temporary fixing and melting portions 51 suitable for the material may be selected.

  As described above, according to the method of manufacturing the battery 1 according to the first embodiment, the case 2 and the sealing plate 3 are hermetically sealed and laser welded by forming the temporarily fixed melting portion 51. 2 can suppress distortion by heat, and the adhesiveness of case 2 and the sealing board 3 can be maintained. Further, the temporarily fixed melting portion 51 is provided at a position (bottom side of the case 2) regardless of the seam melting portion 52. As a result, the release of the electrolytic solution 36 vaporized by the heat at the time of laser welding is not impeded to the outside of the case 2, and good laser welding can be realized.

Second Embodiment
A method of manufacturing a battery according to Embodiment 2 of the present invention will be described using FIGS. 3A and 3B. FIGS. 3A and 3B are schematic cross-sectional views of an example of the laser welding process for sealing the case 2 and the sealing plate 3 of the cylindrical battery 1 according to the second embodiment of the present invention.

  In the second embodiment, points different from the first embodiment will be mainly described. In the second embodiment, the same or similar configuration as that of the first embodiment is described with the same reference numeral. Further, in the second embodiment, the description overlapping with the first embodiment is omitted.

  In the second embodiment, the point that the laser beam 42 is irradiated from the outside to the inside of the side wall of the case 2 and the temporarily fixed melting portion 53 penetrates the side wall of the case 2 and the inside of the rising portion 37 of the sealing plate 3 Is different from that of the first embodiment.

  As shown in FIG. 3A, the sealing plate 3 is fitted to the inner periphery of the opening 21 of the case 2 so that the end face of the opening end 22 of the case 2 and the end face of the rising portion 37 of the sealing plate 3 are aligned. In this state, the region (fitting region) where the inner wall of the case 2 and the rising portion 37 are fitted is irradiated with the laser beam 41 from the side direction (X direction) of the case 2 to form the temporarily fixed melting portion 53 Form

  Specifically, the laser beam 41 is irradiated from the outside to the inside of the side wall of the case 2. Thus, the temporarily fixed melting portion 53 is formed by melting the side wall of the case 2 and the rising portion 37 of the sealing plate 3.

  In the second embodiment, the temporarily fixed melting portion 53 is formed so as to penetrate the side wall of the case 2 and not to penetrate the rising portion 37. That is, the temporarily fixed melting portion 53 is formed in a state of being embedded in the rising portion 37.

  As in the first embodiment, after forming the temporarily fixed melting portion 53, as shown in FIG. 3B, at the open end 22 of the case 2 and the end of the rising portion 37, the upper side of the case 2, ie, the end face The laser beam 42 (second laser beam) is irradiated from the vertical direction (Y direction). As a result, the seam melting portion 52 is formed by melting the opening end 22 of the case 2 and the end of the rising portion 37.

  In the second embodiment, the laser beam 41 is irradiated in a pulse shape of about 10 ms, and reaches the inside of the rising portion 37 of the sealing plate 3 from the outside of the case 2 and does not reach the inner side wall of the rising portion A melting portion 53 is formed.

  In the second embodiment, the laser beam 41 is irradiated from the outside of the case 2 toward the rising portion 37 of the sealing plate 3. The temporarily fixed melting portion 53 is formed so as to reach the inside of the rising portion 37 of the sealing plate 3 from the outside of the case 2 but not to reach the inner side wall of the rising portion 37. That is, although the temporarily fixed melting portion 53 penetrates the side wall of the case 2, it does not penetrate the rising portion 37 of the sealing plate 3.

  The length of the temporarily fixed melting portion 53 is smaller than the sum of the thickness of the side wall of the case 2 and the thickness of the rising portion 37 of the sealing plate 3. The length of the temporarily fixed melting portion 53 means the depth (the length in the X direction) of the temporarily fixed melting portion 53 directed from the outer wall surface of the case 2 to the inside of the case 2.

  According to the method of manufacturing the battery 1 of the second embodiment, the temporarily fixed melting portion 53 is formed by irradiating the laser beam 41 from the outside to the inside of the side wall of the case 2. Thereby, in the second embodiment, the temporarily fixed melting portion 53 can be easily formed as compared with the first embodiment.

  Further, by forming the temporary fixing fusion portion 53 which penetrates the side wall of the case 2 but does not penetrate the rising portion 37 of the sealing plate 3, spatter generated when forming the temporary fixing fusion portion 53 is inside the case 2 It can suppress scattering. As a result, it is possible to suppress the spatter from adhering to the electrode portion and / or the gasket 33 disposed inside the case 2 and damaging these components. In addition, by suppressing the spatter scattering, it is possible to suppress the decrease in the amount of molten metal of the temporarily fixed melting portion 53 and to suppress the reduction in strength.

  The method for producing a battery of the present invention is useful for producing a battery, for example, a lithium ion battery, a nickel hydrogen battery, etc., in which a case and a sealing body are sealed and welded using a laser.

DESCRIPTION OF SYMBOLS 1 battery 2 case 21 opening 3 sealing plate 31 flange 32 positive electrode terminal 33 gasket 34 positive electrode lead 35 electrode group 36 electrolyte solution 41 laser beam 42 for forming temporary fixing fusion part laser light 51 for forming fusion part 51 temporary fixing fusion part 52 seam Melting portion 53 Temporary fixing portion 54 Through hole 61 Electrolyte 62 Evaporated electrolyte 102 Case 103 Sealing plate 142 Laser beam 152 Weld portion 161 Electrolyte 162 Electrolyzed electrolyte 202 case 203 Sealing plate 242 Laser light 251 Temporary fixing portion 252 Melting part 254 hole 261 Electrolyte 262 Vaporized electrolyte

Claims (5)

A method of manufacturing a battery, comprising: sealing an opening of a case for containing an electrolytic solution with a sealing plate,
Fitting a rising portion projecting on the upper surface side of the sealing plate at the outer edge of the sealing plate to the inner periphery of the opening of the case;
The sealing plate is used as the case by irradiating the first laser beam from the side direction of the case to the region where the case and the rising portion are fitted and melting the side wall of the case and the rising portion. Forming a temporarily fixed melting portion for temporarily fixing,
By irradiating the second laser beam to the open end of the case and the end of the rising portion to melt it, the open end of the case and the rising portion are separated from the temporary fixing fusion portion. Forming a seam melt welded to the end,
A method of manufacturing a battery, including:   The method of manufacturing a battery according to claim 1, wherein the step of forming the temporary fixing melting portion includes irradiating the first laser light from the inside to the outside of the case. The step of forming the temporary fixing melt includes irradiating the first laser light from the outside to the inside of the case,
The length of the temporary fixing fusion portion from the outer wall surface of the case to the inside of the case is smaller than the sum of the thickness of the side wall of the case and the thickness of the rising portion.
The manufacturing method of the battery of Claim 1.   The step of forming the temporary fixing fusion portion includes forming a keyhole at a position where the temporary fixing fusion portion is formed when irradiating the first laser light. The manufacturing method of the battery as described in one term.   5. The method according to claim 1, wherein the step of forming the temporarily fixed melting portion includes obliquely irradiating the first laser light to the side wall of the case and the side wall of the rising portion. Method of producing batteries.

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