JP2005268072A - Battery and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a welding area constant in a welding process for connecting an electrode body, a sealing body, and an outer container even if a position where an electrode rod presses a current collector lead is shifted and a sufficient welding strength is ensured. Provided is a sealed battery including an electrical lead part.
An exterior container having an opening and serving as a terminal of one electrode; an electrode body disposed in the exterior container; and the opening is sealed by a sealing body also serving as a terminal of the other electrode; A battery in which at least one of the one electrode of the electrode body and the outer casing, or the other electrode of the electrode body and the sealing body is welded via a current collector, wherein the current collector is one of the electrode bodies A main body connected to the end of the main body and a current collecting lead extending from the main body and welded to a sealing body or an outer container, and a plurality of protrusions are provided at the end of the current collecting lead, and The height of the protrusion located at the center is higher than the height of the protrusion at the periphery of the protrusion.
[Selection] Figure 1

Description

  The present invention relates to a battery and a method for manufacturing the same, and more particularly to the structure of a current collecting lead.

  Generally, a sealed storage battery such as a nickel-hydrogen storage battery or a nickel-cadmium storage battery has a separator interposed between a positive electrode plate and a negative electrode plate, and these are spirally wound to form a spiral electrode body. The main body of the current collector is connected to at least one of the upper and lower ends of the body. The spiral electrode body is housed in a metal outer container, and a current collecting lead extending from the main body portion of one current collector is welded to the lower surface of the sealing body, and then an insulating gasket is formed at the opening of the outer container. It is configured to be hermetically sealed by attaching a sealing body with a gap interposed therebetween.

  However, in the welding process for connecting the electrode body of the sealed secondary battery, the sealing body, and the outer container, short-circuiting due to welding spatter or contamination of impurities is often a problem. Generally, in the sealing body welding process, the work in progress finished until the current collector welding process flows between the fixed sealing body and the electrode rod, so that the in-process position variation, that is, the current collector position variation is large, When designing the current collector lead, it is necessary to consider the variation.

  11 to 13 are diagrams schematically showing a method for manufacturing such a battery. First, the electrode body 111 is inserted into the bottomed outer casing 110 (see FIG. 11). The electrode body 111 is formed by winding a positive electrode and a negative electrode with a separator interposed therebetween, and current collectors are provided on the positive electrode and the negative electrode. For example, when the exterior container 110 is used as a negative electrode, a current collecting lead 113 extending upward from a positive electrode current collector is connected.

  Next, the side wall of the outer casing 110 in the vicinity of the upper end of the electrode body 111 is recessed in the circumferential direction to form a groove 112, and the negative electrode current collector and the bottom of the outer casing 110 are welded and the current collecting lead 113. And the sealing body 114 are welded. Thereafter, a predetermined amount of electrolytic solution is put, and the sealing body 114 is placed in the groove 112 (see FIG. 12).

  After mounting the sealing body 114, the opening end of the exterior container 110 is bent and fitted to the sealing body 114 side, and finally a load is applied in the bottom direction of the exterior container 110 to seal (see FIG. 13).

  In such a battery, the electric resistance (hereinafter referred to as internal resistance) in the welded portion connecting the current collecting lead 113 and the sealing body 114 greatly affects the battery characteristics. If done, a large voltage drop occurs at the weld.

In view of this, a configuration has been proposed in which a protruding portion is provided in the welded portion of the current collecting lead 113 so that the internal resistance can be reduced (see Patent Documents 1 and 2).
“Patent Document 1” describes that a protrusion is provided on a current collector lead for the purpose of improving welding quality. Furthermore, “Patent Document 2” describes that one row or a circumferential protrusion is provided.

  However, in spite of the technical improvements described in “Patent Document 1” or “Patent Document 2”, when the equipment variation such as the in-process position variation and the current collection lead rise variation is taken into consideration, the electrode rod is Since the position where the lead is pressed changes, parts other than the protrusions are welded, or the welding area changes depending on the welding position, resulting in explosion and weak welding strength, making it difficult to obtain stable quality.

JP-A-6-275253 JP 9-330697 A

  However, in the conventional configuration, the current collector lead 113 melted during welding of the sealing body 114 explodes, and this is mixed into the battery and causes a short circuit, and the welding strength varies. There was a problem that it was easy.

  That is, when the current collecting lead 113 and the sealing body 114 are welded, the current collecting lead 113 and the sealing body 114 are abutted against each other, but the abutting position is deviated from a predetermined position due to equipment variation or the like. There is.

  For this reason, for example, when a protruding portion is provided in the welded portion of the current collecting lead 113, the current-collecting lead 113 shifted in position is detached from the protrusion, the current collecting lead 113 is inclined, The welding rod protrudes from the current collecting lead 113 or the like. Further, since the current collecting lead 113 is pushed by the welding electrode during welding, the current collecting lead 113 may be bent by this force.

  Further, when the protruding portion is not provided, the current collecting lead 113 does not tilt, but in this case, since the current collecting lead 113 and the sealing body 114 are in surface contact, the current collecting lead 113 and the sealing body It is difficult to always obtain a constant contact area due to the surface state 114, smoothness, and the like.

  Thus, if the contact area between the current collecting lead 113 and the sealing body 114 changes depending on the situation, even if welding is performed under the same welding conditions, explosion may occur, welding strength may be reduced, and internal resistance may be increased. Inconvenience occurs.

Therefore, the present invention has an object to provide a battery with high reliability without causing explosions, decreasing welding strength, and increasing internal resistance even when equipment variation exists. And
That is, the object of the present invention is to maintain a constant welding area and ensure sufficient welding strength even if the position where the electrode rod presses the current collecting lead is shifted in the welding process for connecting the electrode body, the sealing body, and the outer container. It is an object of the present invention to provide a sealed battery having a current collecting lead having a shape.

  Another object of the present invention is to suppress the generation of defective products and improve the yield of products by stabilizing the quality of the welding process in the manufacture of batteries.

  The battery of the present invention is sealed by an outer container having an opening and serving as a terminal of one electrode, an electrode body disposed in the outer container, and a sealing body in which the opening also serves as a terminal of the other electrode A battery in which at least one of the one electrode of the electrode body and the outer casing, or the other electrode of the electrode body and the sealing body is welded via a current collector, the current collector being the electrode body A main body connected to one end of the main body and a current collecting lead extending from the main body and welded to a sealing body or an outer container, and a plurality of protrusions are provided on the end of the current collecting lead. And the height of the protrusion located in the central part among the plurality of protrusions is higher than the height of the protrusion in the peripheral part.

  With this configuration, even when the abutting position of the current collector and the sealing body is shifted, when the abutting, the sealing body first comes into contact with the protrusion at a high position, and then comes into contact with the surrounding protrusion. The contact area with the sealing body can be made constant at all times, and the surfaces of the current collecting lead and the sealing body are parallel to each other, and welding with a desired welding strength and electrical resistance can be achieved without causing explosion.

  In the battery of the present invention, the protrusion provided at the end of the current collecting lead is disposed at the circumference of a circle including a polygonal apex or ellipse and the center of gravity of the shape, and is positioned at the center of gravity in the protrusion. The protrusion height to be included is higher than other protrusion heights.

  In the battery of the present invention, a gas discharge hole is provided in a central portion of the sealing body for welding the current collecting lead.

  In the battery of the present invention, the sealing body welded portion has a ring shape.

  In the battery according to the present invention, the shape of the protrusion is arranged at the apex and the center of gravity of a quadrangle.

  The method of the present invention includes an exterior container having an opening and serving as a terminal of one electrode; an electrode body disposed in the exterior container; and a sealing body in which the opening serves as a terminal of the other electrode A method of manufacturing a battery, wherein at least one welding step of one electrode of the electrode body and the outer casing, or the other electrode of the electrode body and the sealing body, And using a current collecting lead provided with a plurality of protrusions formed so that the height of the protrusion located at the center is higher, and contacting the protrusions against a sealing body or an outer container for welding.

  With this configuration, even if the abutting position of the current collector and the sealing body is shifted, the surfaces of the current collecting lead and the sealing body are first brought into contact with each other by the protrusion located at the center when the abutting is performed. The protrusion and the sealing body surface come into contact with each other, and the contact area can be made constant at all times, so that welding having a desired welding strength and electric resistance can be realized without causing explosion.

  According to the present invention, even when the current collector lead pressing position of the electrode rod changes due to equipment variations during welding in the battery manufacturing process, it becomes possible to keep the welding area constant and obtain sufficient welding strength.

The best mode for carrying out the invention will be described in detail with reference to the drawings.
Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments and examples.
In the present invention, a plurality of protrusions formed so as to have a higher center are juxtaposed to a current collector lead connected to a main body portion (hereinafter referred to as a current collector) of the current collector, and are butt-matched to a sealing body. At this time, the projection comes into contact with the sealing body so that the contact surface is always constant. Protrusions are arranged at the apex and center of gravity of the quadrangle, and the center of gravity projection is designed to be higher than the apex projection height, so even if the current collector lead position of the electrode rod changes due to equipment variations during welding, Welding is possible at three points at two vertices of a quadrangle, the welding area can be kept constant, spatter is reduced, and sufficient welding strength can be obtained.
In the following, the battery of the present invention and the method for producing the same will be described with reference to the drawings.

  FIG. 1 is a view showing a welding state of the sealing body 24 and the current collecting lead 18, FIG. 1 (a) is a view seen from the current collecting lead 18 side, and FIG. 1 (b) is a side sectional view. . The current collecting lead 18 is provided with five protrusions 35 having a quadrangular apex and a center of gravity. Before welding, the protrusions at the center of gravity are formed so as to be higher than the surrounding protrusions.

  Next, an embodiment when the present invention is applied to a nickel-cadmium storage battery will be described in detail with reference to the drawings. FIG. 5 (a) is a schematic view showing a positive electrode current collector of the present invention, and FIG. 1 (b) is a side view of the lead.

  As shown in FIG. 5 (a), the positive electrode current collector 16 has a substantially circular main body (for example, a diameter of 17.4 to 17.6 mm and a thickness of 0.28 to 0.32 mm), and a main body Is formed in one piece with the main body and has a rectangular shape (for example, the width is 7.3 to 7.5 mm, the length is 13.7 to 13.9 mm, and the thickness is 0.28 to 0.32 mm). It is comprised from the current collection lead 18 extended. The main body is formed with an opening for pouring at the center thereof.

  The welding projection 35 is provided at the end of the current collecting lead 18. The height of the end of the peripheral portion is 0.15 to 0.20 mm in any shape, and the end of the end at the center is The height is preferably 0.25 to 0.30 mm. The difference between the height of the peripheral edge and the height of the central edge is 0.05 to 0.15 mm, preferably 0.05 to 0.10 mm.

The metal substrate used as a member of the current collector 16 of the present invention is a substrate having a metal skeleton provided with three-dimensional pores having a uniform or arbitrary size. Examples of the material include gold, silver, platinum, copper, iron, tin, nickel, chromium, aluminum, carbon, and alloys thereof. Moreover, what plated the specific metal on the said metal can also be used preferably.
Examples of the shape of the metal substrate include a metal fiber sintered body, a metal felt, a spongy (foaming) metal body, a non-woven metal body, and a uniform metal.
The metal substrate used as a member of the current collecting lead of the present invention may be appropriately selected according to the type of the current collecting lead, but nickel that is stable in an alkaline electrolyte is preferable. The positive electrode current collector 16 of the present invention can be formed by punching a nickel plated steel sheet.

Next, production of a nickel-cadmium storage battery will be described.
After forming a nickel sintered porous body on the surface of the punching metal, a positive electrode active material mainly composed of nickel hydroxide is filled into the sintered porous body by a chemical impregnation method to produce a sintered nickel positive electrode 13. Further, a non-sintered cadmium negative electrode 14 is prepared by coating the core with a paste-like negative electrode active material mainly composed of cadmium oxide powder. Next, the nickel positive electrode 13 and the cadmium negative electrode 14 are spirally wound with a separator 15 interposed therebetween to form a spiral electrode body 12.

  The upper end of the spiral electrode body 12 exposes the end of the punching metal, which is the nickel positive electrode plate core, and forms a positive electrode conductive edge, while the lower end of the spiral electrode body is the negative electrode plate of the cadmium negative electrode The end of the core is exposed to form a conductive edge for negative electrode. The spiral electrode body 12 has a diameter of 21.8 to 21.9 mm and a height of 34.7 to 35.7 mm.

  Then, the main body portion of the positive electrode current collector 16 is placed on the upper part of the spiral electrode body 12, and resistance welding is performed while pressing a protrusion protruding downward from the peripheral edge of each opening into the conductive edge for positive electrode. On the other hand, a negative electrode current collector is disposed below the spiral electrode body, and resistance welding is performed while pressing the protrusions of the negative electrode current collector into the negative electrode conductive edge. The negative electrode current collector is formed of a steel plate in a circular shape, and a large number of openings similar to those of the main body of the positive electrode current collector 16 are provided in a circular shape. Is formed.

  As for the shape of the protrusion of the negative electrode current collector, the height of the protrusion at the center of gravity of the current collector of the present invention is preferably higher than that of the peripheral portion.

  Next, as shown in FIG. 2, a bottomed cylindrical metal outer container 11 in which an iron base material is plated with nickel is prepared, and the base portion (the main body portion and the main body portion) of the current collecting lead 18 of the positive electrode current collector 16 is prepared. After folding the boundary portion with the current collector lead 18, the spiral electrode body 12 is inserted into the metal outer container 11, and one welding electrode is inserted from the liquid injection opening of the positive electrode current collector 16. While making contact with the negative electrode current collector, the other welding electrode is brought into contact with the bottom of the metal outer casing 11 to spot weld the negative electrode current collector and the bottom of the metal outer casing 11. The diameter (outer dimensions) of the metal outer container 11 is 22.0 to 23.0 mm (inner diameter is 21.6 to 22.2 mm), and the height is in the range of 44.6 to 44.8. preferable.

  Next, after placing a spacer on the upper part of the spiral electrode body 12 wound in a spiral shape with a separator interposed therebetween, a sealing body 24 having a ring-shaped insulating gasket 27 mounted on the peripheral edge portion is prepared. As shown in FIG. 4, the tip of the current collector lead 18 of the positive electrode current collector 16 is brought into contact with the bottom of the sealing body 24, and the bottom and the tip of the sealing body 24 are connected by resistance welding. Thereafter, an electrolytic solution (8N potassium hydroxide (KOH) aqueous solution containing lithium hydroxide (LiOH) and sodium hydroxide (NaOH)) is injected into the metal outer container 11. Next, a sealing body 24 fitted with a gasket 27 is placed on an inwardly projecting portion formed in an annular shape on the upper part of the outer container 11.

  Here, the groove 23 abuts the grooved piece on the side surface of the outer container 11 slightly above the upper end of the electrode body 12 and gradually increases the contact force while rotating in the circumferential direction of the outer container 11 in this state. It is formed by.

  The sealing body 24 is formed by joining two plate-like metal plates 25 and 26 facing each other so that a space is formed inside, and a gasket 27 is attached to an outer peripheral portion thereof.

  An opening 28 is formed at the center of the metal plate 26, and a valve plate 29 is disposed in the internal space so as to close the opening 28. Further, the valve plate 29 is urged toward the opening 28 by a spring 30. Yes.

  The sealing body 24 is provided with a gas vent hole (not shown). For example, when the battery is overcharged and the internal pressure exceeds a specified value, the valve plate 29 is pushed up by the pressure and the gas escapes into the atmosphere. Be able to.

  The sealing body 24 and the current collecting lead 18 are welded with the projection of the current collecting lead 18 abutted against the ring-shaped flat portion 31 of the metal plate 26 in which the opening 28 is formed while applying a predetermined load. The electrode is brought into contact with the current collecting lead 18 and welded.

  Next, the sealing body 24 is placed on the groove 23 while the current collecting lead 18 is bent, and the opening end of the outer container 11 is bent and fitted inside. Thereafter, the height of the battery is adjusted by applying a load to the outer container 11.

By fitting the open end, the gasket 27 is elastically deformed and the outer container 11 is sealed, and the total height of the battery is adjusted to the standard size by applying a load in the direction of the bottom of the can along the can axis.
In this way, as shown in FIG. 4, the opening edge of the metal outer container 11 is sealed inward by caulking the opening edge of the metal outer container 11, and nickel having a nominal capacity of 1.3 Ah is sealed. -A cadmium battery can be assembled.

  FIG. 5 is a view showing a state before welding of the positive electrode current collector lead of the embodiment, FIG. 5 (a) is a top view, and FIG. 5 (b) is a cross-sectional view taken along line AA in FIG. 5 (a). FIG. The protrusion at the center of gravity is formed higher than the surrounding protrusions.

  6 is a view showing a positive electrode current collector lead of a lead having one protrusion of Comparative Example 1, FIG. 6 (a) is a top view, and FIG. 6 (b) is a cross-sectional view of FIG. It is B sectional drawing. 7 is a view showing a positive electrode current collector lead of Comparative Example 2, FIG. 7 (a) is a top view of a lead having a plurality of protrusions, and FIG. 7 (b) is a cross-sectional view of FIG. It is C sectional drawing. FIG. 7B shows that the protrusion height in the peripheral portion is the same as the protrusion height in the central portion. 8A and 8B are diagrams showing a positive electrode current collector lead without a protrusion of Comparative Example 3, FIG. 8A is a top view, and FIG. 8B is a cross-sectional view taken along the line DD in FIG. is there.

  FIG. 9 shows a schematic diagram of welding between the sealing plate on the upper surface of the battery and the positive electrode current collector lead. FIG. 9A shows that the tip of the welding rod is disposed at the center and all the projections including the projection at the center of the current collector lead are welded. On the other hand, in FIG. 9B, FIG. 9C, FIG. 9D, and FIG. 9E, the tip of the welding rod is shifted to the left, top, bottom, or right, and It indicates that a part of the protrusion is not welded.

FIG. 10 is a diagram showing another embodiment of the positive electrode current collector of the present invention, and FIG. 10 (a) is a top view of the positive electrode current collector. It is shown that it is arranged. FIG. 10B shows a cross-sectional view of the positive electrode current collector lead.
FIG. 10C is a top view showing still another embodiment of the positive electrode current collector of the present invention, in which protrusions having a low peripheral part are arranged on the circumference with respect to protrusions having a high center part. Indicates that FIG. 10D shows a cross-sectional view of the positive electrode current collector lead.

  EXAMPLES In the following, the present invention will be described in more detail with reference to examples, but the scope of the present invention is not limited by these examples.

Example 1
In accordance with the above-described embodiment, current collectors having specifications in which protrusions 35 are arranged at the apexes and the center of gravity of a square as shown in FIGS. 1 and 5 and the center of gravity protrusion height is designed to be 0.1 mm higher than the apex protrusion height. The electrode body with the body welded is inserted into the outer container, the bottom of the outer container and the sealing body are welded, the electrolyte is injected, and then the outer container is caulked to seal the SC size cylindrical nickel- A cadmium battery was manufactured.

Comparative Examples 1-3
An SC size cylindrical nickel-cadmium battery having protrusions on the current collector lead shown in FIGS. 2 to 4 was produced in the same manner as in Example 1.

A battery was manufactured by the above method, and the current collector lead 18 and the sealing body 24 were brought into contact with each other with a load of N = 10 kPa and welding was performed under a 40 A discharge condition.
The sealing body weld strength, weld spatter generation state, and battery defect rate (caused by impurity contamination / weld spatter / weld weakness) of the battery of the present invention prepared in Example 1 and the battery prepared in Comparative Example were measured and evaluated. The measurement condition of the sealing body welding strength is a tensile test at 30 mm / min. Moreover, the evaluation criteria of the spatter generation state and the battery defect rate were in accordance with the process control standard.

  Table 1 shows the measurement results of the welding strength when the welding positions of Example 1 and Comparative Examples 1 to 3 are different. Table 2 shows the test results of the weld spatter generation state and the battery failure rate in Example 1 and Comparative Examples 1 to 3. As is apparent from Tables 1 and 2, in the present invention, three-point welding including the center of gravity projection is possible, the welding area is kept constant, spatter is reduced, and sufficient welding strength can be obtained. It can be seen that in the battery using the positive electrode current collecting lead of the invention, the welding spatter generation state and the battery defect rate are greatly improved as compared with the comparative example.

  The use of the current collector lead having the protrusion of the present invention stabilizes the battery welding process and greatly improves the production yield of the battery, and therefore can be applied to various batteries. For example, when installed in an electronic device, a color notebook computer, pen input computer, pocket computer, notebook word processor, pocket word processor, electronic book player, mobile phone, cordless phone, pager, handy terminal, mobile fax, mobile copy, Portable printer, headphone stereo, video movie, LCD TV, handy cleaner, portable CD, minidisc, electric shaver, electronic translator, car phone, transceiver, electric tool, electronic notebook, calculator, memory card, tape recorder, radio, backup Examples include power supplies and memory cards. Other consumer products include automobiles, electric vehicles, motors, lighting equipment, toys, game equipment, road conditioners, irons, watches, strobes, cameras, medical equipment, and the like. It can also be used in combination with solar cells.

It is the principal part schematic showing the battery before sealing of this invention, Fig.1 (a) is a top view, FIG.1 (b) is the sectional drawing. It is a manufacturing-process figure of the battery of this invention. It is a manufacturing-process figure of the battery of this invention. It is a manufacturing-process figure of the battery of this invention. It is the schematic showing the positive electrode electrical power collector of the Example of this invention, Fig.5 (a) is a top view, FIG.5 ((b) is a side view of the lead | read | reed. FIG. 6 is a view showing a positive electrode current collector lead of Comparative Example 1, FIG. 6 (a) is a top view, and FIG. 6 (b) is a side view of a lead having one protrusion. It is a figure which shows the positive electrode collector lead of the comparative example 2, FIG. 7 (a) is a top view, FIG.7 (b) is a side view of the lead | read | reed which has several protrusion. It is a figure which shows the positive electrode collector lead of the comparative example 3, FIG. 8 (a) is a top view, FIG.8 (b) is a side view of a lead | read | reed without a protrusion. The welding schematic diagram of the sealing board and positive electrode collector lead of the upper surface part of a battery is shown. 9 (a), 9 (b), 9 (c), 9 (d), and 9 (e) show a sealing plate in which the tip of the welding rod is shifted to the center, left, up, down, or right. It shows that it touches. It is a figure showing the embodiment of the other positive electrode electrical power collector of this invention. FIG. 10A is a top view thereof, and FIG. 10B is a sectional view thereof. FIG. 10 (c) is a top view showing still another embodiment of the positive electrode current collector of the present invention, and FIG. 10 (d) is a sectional view thereof. It is a manufacturing process figure of the battery of a prior art example. It is a manufacturing process figure of the battery of a prior art example. It is a manufacturing process figure of the battery of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Exterior container 12 Electrode body 13 Positive electrode 14 Negative electrode 15 Separator 16 Positive electrode collector 17 Negative electrode collector 18 Current collector 24 Sealing body 25, 26 Metal plate 31 Ring-shaped flat part 35 Protrusion

Claims (6)

An exterior container having an opening and serving as a terminal of one electrode; an electrode body disposed in the exterior container; and the opening is sealed by a sealing body also serving as a terminal of the other electrode; A battery in which at least one of the one electrode and the outer casing, or the other electrode of the electrode body and the sealing body is welded via a current collector,
The current collector includes a main body connected to one end of the electrode body, and a current collecting lead extending from the main body and welded to a sealing body or an outer container, and at the current collector lead end A battery, wherein a plurality of protrusions are provided, and among the plurality of protrusions, a protrusion located at a central portion has a height higher than that of a protrusion at a peripheral portion. The battery according to claim 1,
The protrusions provided at the ends of the current collecting leads are arranged at the circumference of a circle including a polygonal apex or ellipse and the center of gravity of the shape, and the height of the protrusion located at the center of gravity is the other of the protrusions Batteries characterized by being higher than the protrusion height. The battery according to claim 1 or 2,
A battery comprising a gas discharge hole in a central portion of the sealing body for welding the current collecting lead. The battery according to any one of claims 1 to 3,
A battery having the sealant welded portion in a ring shape. The battery according to any one of claims 1 to 4,
The battery is characterized in that the shape of the protrusion is arranged at the apex and the center of gravity of a quadrangle. A battery manufacturing method comprising: an exterior container having an opening and serving as a terminal of one electrode; an electrode body disposed in the exterior container; and the opening being sealed by a sealing body also serving as a terminal of the other electrode Because
The welding process of at least one of the one electrode of the electrode body and the outer casing, or the other electrode of the electrode body and the sealing body has a protrusion height positioned at the center portion rather than the protrusion height of the peripheral portion. A method for manufacturing a battery, comprising: using a current collecting lead having a plurality of protrusions formed to be high, and bringing the protrusions into contact with a sealing body or an outer container and welding them.

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