JPH10189026A - Spiral electrode assembly for secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spiral electrode assembly which is preferably amplified for manufacture of a secondary battery having a large energy density, small resistance exothermic heat, and good earthquake resistance in an excellent productivity at a low cost. SOLUTION: A spiral electrode assembly 7 made by wrapping a band-like positive electrode 1 and a band-like negative electrode 2 through the medium of a separator 5 is provided with comb collecting tabs 4A and 4B for introducing a current from the respective electrodes 1 and 2. Moreover, continuous tape parts 4A1 and 4B1 of the comb collecting tabs 4A and 4B are seam-welded one side edge lengthwise of the corresponding band-like electrodes 1 and 2. A protrusion 4A2 of the positive electrode comb collecting tab 4A and a protrusion 4B2 of the negative electrode comb collecting tab 4B protrude from both end faces of the spiral collector 7 in opposite directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spiral-type electrode assembly for a secondary battery, and more particularly to a spiral-type electrode assembly for a secondary battery having a large energy density and good seismic resistance which can be preferably used for an electric vehicle or the like. The present invention relates to a spiral electrode assembly that can be improved.

[0002]

2. Description of the Related Art In order to develop a secondary battery requiring a much larger energy density than a home secondary battery, such as a secondary battery for an electric vehicle, for example, a spiral electrode assembly is provided. Secondary batteries are attracting attention. This is because, in a spiral electrode assembly obtained by laminating and winding a thin and flexible strip-shaped positive electrode and negative electrode via a separator, the effective area of the positive electrode and the negative electrode can be greatly increased. Thereby, the energy density of the secondary battery can be increased. The spiral electrode assembly referred to herein is not necessarily limited to a columnar electrode having a circular cross section, and includes, for example, a prismatic spiral electrode assembly having a rectangular cross section.

In such a spiral electrode assembly, the positive electrode includes a band-shaped metal foil current collector and a positive electrode active material adhered to the surface thereof, and the negative electrode includes a band-shaped metal foil current collector and the same. And a negative electrode active material adhered to the surface. For a secondary battery with a relatively small energy density, a relatively thick and short band-shaped metal foil can be used as the current collector, so the internal resistance of the battery and the leads for drawing current from the current collector There is no particular problem.

However, in the development of a secondary battery requiring an extremely large energy density, such as a secondary battery for an automobile, a band-shaped current collector is further added to further increase the effective area of the positive electrode and the negative electrode. It is desired to be long and thin. However, if the belt-shaped current collector is made thinner, not only does its mechanical strength sharply decrease, but also its electrical resistance per area increases. Therefore, if the current collector is not only thinned but also its length is increased, the internal resistance of the strip-shaped electrode is increased especially in the length direction, and a large voltage drop when a large current flows and a temperature of the battery caused by resistance heating are generated. It becomes difficult to extract a large current from the battery due to a rise or the like. Under such circumstances, Japanese Patent Laid-Open No. 6-26752
In order to solve the problem caused by the increase in the internal resistance in the length direction of the strip electrode, the conventional mounting member 8 is mounted at one place at the center of the side edge along the length direction of the strip electrode or at two places at both ends. Instead of the conventional lead, a strip-like electrode having a plurality of suitable leads attached along its side edge is disclosed.

FIG. 7 is a schematic plan view showing a strip electrode as disclosed in Japanese Patent Application Laid-Open No. 6-267528. The mutual dimensional relations such as length, width, and thickness shown in each drawing of the present application are appropriately changed for clarity of the drawings, and do not represent actual dimensional relations. Absent. The band-shaped positive electrode 1 shown in FIG. 7 includes a band-shaped metal foil positive electrode current collector 1a and positive electrode active materials 1b attached to both surfaces thereof. However, the positive electrode current collector 1a has a portion of a predetermined width along one edge along the length direction thereof exposed without being covered with the positive electrode active material 1b. Along the length direction of the exposed portion of the positive electrode current collector 1a, a plurality of appropriate metal plate leads are attached by spot welding as the positive electrode current collection tab 3a. The strip-shaped negative electrode 2 is formed similarly to the positive electrode 1 and includes a strip-shaped negative electrode current collector 2a, a negative electrode active material 2b, and a plurality of negative electrode current collecting tabs 3b.

A strip-shaped positive electrode 1 and a strip-shaped negative electrode 2 as shown in FIG. 7 have a band-shaped separator (see FIG. 7) in which a portion to which a positive electrode active material 1b is applied and a portion to which a negative electrode active material 2b is applied. (Not shown in FIG. 7) so as to overlap each other, and assembled into a spiral electrode assembly. At this time, since the positive electrode 1 and the negative electrode 2 are stacked and wound so that the positive electrode current collecting tab 3a and the negative electrode current collecting tab 3b project in opposite directions, the positive electrode current collecting tab 3a and the negative electrode current collecting tab 3b come into contact with each other. Any suitable number of current collecting tabs 3a, 3
b can be provided.

[0007]

In a spiral electrode assembly formed by winding a strip-shaped positive electrode 1 and a strip-shaped negative electrode 2 together with a separator as shown in FIG. Strip current collector 1 to increase area
Even if a and 2a are made thinner and longer, each electrode 1,
Since the number of metal plate leads 3a, 3b as an arbitrary number of current collecting tabs can be provided on the side edges along the length direction of the electrode 2 at any appropriate intervals, the inside of each electrode 1, 2 in the length direction can be provided. The problem that it is difficult to extract a large current from the battery due to the increase in resistance can be reduced.

However, in order to alleviate this problem, it is necessary to provide more metal plate leads 3a, 3b as the current collectors 1a, 2a become thinner and longer. If the number of metal plate leads 3a and 3b to be attached to the strip electrodes 1 and 2 increases, the metal plate leads 3a and 3b are attached to the current collectors 1a and 1b one by one by spot welding. This leads to an increase in labor and cost of manufacturing a secondary battery including the electrode assembly.

The current collectors 1a, 1 by spot welding
Since the attachment of the metal plate leads 3a, 3b to the electric vehicle is not sufficiently strong, when a secondary battery including such a large number of leads is used in an electric vehicle, the vibration of the vehicle causes the metal plate leads 3a, 3b to be attached. May fall off. Then, such dropped metal plate leads may cause a short circuit in the battery.

In view of the above-mentioned problems in the prior art, the present invention provides a spiral electrode assembly which can be preferably used for manufacturing a secondary battery having a large energy density and good earthquake resistance. For the purpose, and
It is another object of the present invention to provide a spiral electrode assembly that can be manufactured with good productivity and at low cost.

[0011]

SUMMARY OF THE INVENTION A spiral electrode assembly for a secondary battery according to the present invention comprises a belt-like positive electrode comprising a cathode current collector of a belt-like metal foil and a cathode active material adhered thereto, and a belt-like metal. A spiral electrode assembly in which a strip-shaped negative electrode in which a negative electrode active material is applied on a foil negative electrode current collector is stacked and wound on each other with a separator interposed therebetween, and includes a positive electrode current collector and a negative electrode current collector. The current collector further includes a positive comb current collecting tab and a negative comb current collecting tab for conducting current from each of the current collectors, and each of the comb current collecting tabs includes a continuous metal tape portion and one of the one along the length direction of the tape portion. A plurality of metal protrusions protruding in a comb-like shape from the side edge, and each of the tape portions of the positive comb current collector tab and the negative comb current collector tab corresponds to one of the positive current collector and the negative current collector. Seam welded to one side edge along one of the two lengths, and It is characterized by being protruded in opposite directions from both end faces of the spiral type electrode assembly and the pole protrusions of the comb electrode current collector tabs and the negative electrode comb collecting tab of the protrusion.

In such a spiral electrode assembly for a secondary battery according to the present invention, the plurality of metal projections of the comb-shaped current collecting tab are formed despite the large electrical resistance in the length direction of the thin and long current collector. In addition to enabling a large current to be drawn from the strip electrode, the continuous tape portion of the comb current collector acts to reduce the internal resistance in the length direction of the strip electrode.

Further, since the comb-shaped current collecting tab is welded to the belt-shaped current collector by continuous seam welding, the spiral electrode assembly can be manufactured with good productivity and low cost.

Further, since the comb-shaped current collector tab is firmly welded to the band-shaped current collector by continuous seam welding instead of spot welding, the side edges of the thin band-shaped current collector can be mechanically reinforced. In addition, even if the spiral electrode assembly is used for a secondary battery for a vehicle, the comb-shaped current collecting tab cannot fall off the strip-shaped electrode due to the vibration of the vehicle.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of a spiral electrode assembly for a secondary battery according to the present invention will be described. Note that, as described above, the dimensional relationships such as length, width, and thickness in each drawing do not reflect actual dimensional relationships.

FIG. 1 is a schematic plan view showing an example of a positive electrode comb-shaped current collecting tab or a negative electrode comb-shaped current collecting tab which can be used in the spiral electrode assembly of the present invention. The positive comb-shaped current collecting tab 4A includes a continuous metal tape portion 4A1 and a plurality of metal protrusions 4A2 protruding at a predetermined interval from one side edge along the length direction. The negative comb-shaped current collecting tab 4B can also have the same structure as the positive comb-shaped current collecting tab 4A, and includes a continuous metal tape portion 4B1 and a plurality of metal protrusions 4B2.

FIG. 2 shows a strip-shaped positive electrode or a strip-shaped negative electrode. The band-shaped positive electrode 1 includes a band-shaped metal foil positive electrode current collector 1a and a positive electrode active material 1b attached to both surfaces thereof. However, as can be seen from FIG. 2, the positive electrode current collector 1a has a constant width portion along one side edge along the length direction thereof exposed without the positive electrode active material 1b being attached. The strip-shaped negative electrode 2 can also have the same structure as the strip-shaped positive electrode 1, and includes a strip-shaped metal foil-made negative electrode current collector 2a and a negative electrode active material 2b attached to both surfaces thereof.

In FIG. 3, the comb-shaped current collecting tab of FIG.
3 shows a state in which the electrodes are welded to the band-shaped electrode by seam welding. That is, the positive electrode comb-shaped current collecting tab 4A is seam-welded to the band-shaped current collector 1a exposed at one side edge along the length direction of the band-shaped positive electrode 1. This seam welding is continuously performed along the length direction of the metal tape portion 4A1. Therefore, the metal tape portion 4A1 has an effect of reducing the internal resistance in the length direction of the strip-shaped positive electrode 1, and also has an effect of mechanically reinforcing the exposed side edge of the strip-shaped current collector 1a made of a thin metal foil. . Similarly to the positive electrode comb-shaped current collecting tab 4A, the negative electrode comb-shaped current collecting tab 4B can be seam-welded to one edge along the length direction of the strip-shaped negative electrode 2.

FIG. 4 schematically illustrates a continuous assembly process of a spiral electrode assembly according to the present invention. In this assembling process, first, a strip-shaped positive electrode 1, a strip-shaped negative electrode 2, a positive electrode comb-shaped current collecting tab 4A, a negative electrode comb-shaped current collecting tab 4B, and a separator 5 are prepared. And the positive electrode current collecting tab 4
A is continuously welded to the strip-shaped positive electrode 1 by a seam welding machine 6A, and similarly, the negative electrode current collecting tab 4B is continuously welded to the strip-shaped negative electrode 2 by another seam welding machine 6B. The strip-shaped positive electrode 1 and the strip-shaped negative electrode 2 to which the positive electrode current collecting tab 4A and the negative electrode current collecting tab 4B are respectively seam-welded continue with the positive electrode active material region 1b and the negative electrode active material region 2b interposed by the band-shaped separator 5. The spirally wound electrode assembly 7 is assembled. In the process of assembling the spiral electrode assembly 7, the step of spot welding individual metal plate leads 3a as in the prior art shown in FIG. Since the strip-shaped electrode and the separator can be wound as they are while continuously seam-welding, the spiral electrode assembly 7 according to the present invention can be manufactured with high productivity and low cost. The strip-shaped electrodes 1 and 2 supplied in this assembly process, the comb-shaped current collecting tabs 4A and 4B, and the separator 5
Needless to say, may be supplied so as to be drawn from a roll.

FIG. 5 is a schematic sectional view more clearly illustrating the seam welding process shown in FIG. As can be seen from this figure, the positive electrode active material 1b is attached to both surfaces of the positive electrode current collector 1a of a band-shaped metal foil, and the band-shaped positive electrode 1 extends in a direction perpendicular to the drawing. The continuous tape portion 4 of the positive electrode comb-shaped current collecting tab 4A is provided at a portion exposed from the positive electrode active material 1b at a constant width on one side edge along the length direction of the belt-shaped positive electrode current collector 1a.
A1 (see also FIGS. 1 and 3) is overlaid. Then, the band-shaped positive electrode current collector 1a and the positive electrode comb-shaped current collecting tab 4A which are overlapped with each other are connected to two seam welding wheels 6A connected to the AC power source 8.
And seam welding can be continuously performed with the rotation of the welding wheel 6A (see also FIG. 4). Similarly, a negative electrode comb-shaped current collecting tab 4B is overlapped on one side edge of a band-shaped negative electrode 2 including a band-shaped negative electrode current collector 2a having both surfaces to which a negative electrode active material 2b is applied, and a seam welding wheel connected to a power supply 8 Continuous seam welding is performed by the rotation of 6B.

FIG. 6 is a schematic sectional view showing an example of a secondary battery using the spiral electrode assembly 7 according to the present invention, which can be manufactured by the steps shown in FIG. That is, the spiral electrode assembly 7 is inserted into the negative electrode can 10, and the electrolytic solution is injected into the negative electrode can 10. The negative electrode can 10 is sealed by a positive electrode terminal 11 and an electrically insulating gasket 12. The positive electrode active material 1b and the negative electrode active material 2b immersed in the electrolytic solution in the negative electrode can 10 cause an ionic reaction via the porous separator 5 to generate a charge / discharge current of the secondary battery. The band-shaped positive electrode current collector 1a is electrically connected to the positive electrode terminal 11 via a positive electrode comb-shaped current collecting tab 4A, and the band-shaped negative electrode current collector 2a is connected to the negative electrode can 1 via a negative electrode comb-shaped current collecting tab 4B.
Connected to 0. That is, the secondary battery in FIG. 6 can perform charging and discharging between the positive electrode terminal 11 and the negative electrode can 10. In FIG. 6, for clarity of the drawing,
A spiral electrode assembly 7 having a lesser number of turns is shown. Further, the horizontal cross section of the battery of FIG. 6 is not limited to a circular shape, and may have a rectangular cross section.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a secondary battery using a spiral electrode assembly according to the present invention and a comparative example of a secondary battery using a spiral electrode assembly according to the prior art will be described.

[Example 1] (Preparation of strip-shaped positive electrode) LiCoO as positive electrode active material 1b
₂ and artificial graphite as a conductive material were mixed at a weight ratio of 9: 1 to prepare a positive electrode mixture. An NMP solution was prepared by dissolving polyvinylidene fluoride as a binder in N-methyl-2-pyrrolidone (NMP). Then, the slurry was prepared by kneading the positive electrode mixture and the NMP solution such that the weight ratio of the positive electrode mixture to polyvinylidene fluoride was 95: 5. This slurry was applied on both sides of an aluminum foil as a positive electrode current collector 1a by a doctor blade method, and dried in a vacuum at 150 ° C. for 2 hours to produce a belt-shaped positive electrode 1. However, the aluminum foil as the positive electrode current collector 1a had a thickness of 0.02 mm and a length of 4000 mm. Also, 15 m from one side edge along the length direction of the positive electrode current collector 1a.
The portion having a width of m was left as an exposed portion without application of the slurry, and the slurry was applied to the remaining portion having a width of 200 mm.

(Preparation of Stripped Negative Electrode) An air stream was injected into the graphite mass and pulverized (jet pulverized) to prepare a graphite powder. According to the X-ray diffraction measurement, the average interplanar spacing d of the (002) planes stacked in the C-axis direction of the obtained graphite powder crystal.
₀₀₂ was 3.356 °, and the size Lc of the crystallite in the C-axis direction was 1000 ° or more. Then, polyvinylidene fluoride as a binder was dissolved in NMP to prepare an NMP solution, and kneaded so that the weight ratio of the graphite powder to polyvinylidene fluoride was 85:15 to prepare a slurry. This slurry was applied to both sides of a copper foil as a negative electrode current collector 2a by a doctor blade method.
The strip-shaped negative electrode 2 was produced by vacuum drying for an hour. However, the copper foil as the negative electrode current collector 2a is 0.02 m
m and a length of 4200 mm. Further, 15 m from one side edge along the length direction of the negative electrode current collector 2a.
The portion having a width of m was exposed without being applied with the slurry, and the remaining portion having a width of 210 mm was coated with the slurry.

(Preparation of Electrolyte Solution) An organic electrolyte solution was prepared by dissolving LiPF ₆ at a ratio of 1 mol / liter in a solvent in which ethylene carbonate and diethyl carbonate were mixed at a volume ratio of 1: 1.

(Assembly of Battery) Using the strip-shaped positive electrode 1, strip-shaped negative electrode 2, and organic electrolyte prepared as described above, FIG.
The secondary battery A as shown in was manufactured. However, a porous membrane made of ion-permeable polypropylene was used as the separator 5.

As the positive comb-shaped current collecting tab 4A, a 0.1.
An Al foil having a thickness of 1 mm was used. This Al foil positive electrode comb-shaped current collecting tab 4A included a continuous tape portion 4A1 having a width of 10 mm and protruding portions 4A2 arranged at intervals of 600 mm. Each of the protrusions 4A2 had a length of 50 mm and a width of 10 mm. On the other hand, a Ni foil having a thickness of 0.1 mm was used as a negative electrode comb-shaped current collecting tab. The Ni foil negative electrode comb-shaped current collecting tab 4B has continuous tape portions 4B1 and 60 having a width of 10 mm.
The protrusions 4B2 were arranged at intervals of 0 mm.
The protrusions 4B2 had a length of 50 mm and a width of 10 mm.

[Embodiment 2] The interval between the projecting portions of each of the positive electrode comb-shaped current collecting tab 4A and the negative electrode comb-shaped current collecting tab 4B is 200.
A battery B of Example 2 was assembled in the same manner as the battery A of Example 1 except that the thickness was changed to mm.

[Embodiment 3] The interval between the projecting portions of each of the positive electrode comb-shaped current collecting tab 4A and the negative electrode comb-shaped current collecting tab 4B is set to 800.
A battery C of Example 3 was assembled in the same manner as the battery A of Example 1 except that the thickness was changed to mm.

[Comparative Example 1] The corresponding positive and negative electrode slurries were applied to the entire surfaces of both of the positive and negative electrode current collectors 1a and 2a, respectively. Was produced. As a positive electrode current collecting tab, 3
One individual Al plate lead was used. Each of these Al plate leads had a thickness of 0.1 mm, a width of 10 mm, and a length of 250 mm. These three positive electrode current collection tabs were mounted at the center and both ends in the length direction of the strip-shaped positive electrode so as to cross the strip-shaped positive electrode in the width direction. That is, one end in the length direction of each of these positive electrode current collection tabs is made to coincide with one side edge along the length direction of the band-shaped positive electrode, and the other end in the length direction of the positive electrode current collection tab is the band-shaped positive electrode. It was projected from the other side edge. Also, two Ni plate leads were used as the negative electrode current collecting tab. These Ni plate leads are 0.1 mm thick,
It had a width of 10 mm and a length of 260 mm.
These two negative electrode current collecting tabs are attached to both ends in the length direction of the strip negative electrode, and one end in the length direction of the negative electrode current collecting tab extends along the length direction of the strip negative electrode as in the case of the positive electrode current collecting tab. From one side edge. The other conditions were the same as those of the battery of Example 1, and the battery D of Comparative Example 1 was assembled.

COMPARATIVE EXAMPLE 2 Individual positive electrode current collecting tabs were
Comparative Example 1
The battery E of Comparative Example 2 was assembled under the same conditions as those of the battery D.

Comparative Example 3 Except that a plurality of individual positive electrode current collecting tabs were mounted at intervals of 600 mm, and two individual negative electrode current collecting tabs were mounted at both ends in the longitudinal direction of the strip negative electrode. Battery F of Comparative Example 3 was assembled under the same conditions as Battery D of Comparative Example 1.

[Comparative Example 4] A comparative example except that a plurality of individual positive electrode current collecting tabs were mounted at intervals of 800 mm and two negative electrode current collecting tabs were mounted at both ends in the length direction of the strip-shaped negative electrode. Battery G of Comparative Example 4 was assembled under the same conditions as Battery D of No. 1.

[Measurement of Internal Resistance of Battery] With respect to the batteries according to the various examples and the various comparative examples manufactured as described above, the internal impedance of each battery was measured by measuring the AC impedance at 1 kHz at room temperature. Measured.

Table 1 shows the internal resistance values of various batteries in the above Examples and Comparative Examples.

[0036]

[Table 1]

As is apparent from Table 1, all of the secondary batteries A to C in Examples 1 to 3 using the spiral electrode assembly according to the present invention were compared using the spiral electrode assembly according to the prior art. It can be seen that the secondary batteries have lower internal resistance than any of the secondary batteries D to G in Examples 1 to 4. In particular, the interval between the protruding portions of the comb-shaped current collector tab is 3 times the width of the band-shaped current collector.
It can be seen that the secondary batteries A and B in Examples 1 and 2, which are twice or less, have a small internal resistance of 20 mΩ or less and can be preferably used as a secondary battery for electric vehicles.

Although the lithium secondary battery has been described in the above Examples and Comparative Examples, the spiral electrode assembly for a secondary battery according to the present invention can be used for various other secondary batteries. Needless to say.

[0039]

As described above, according to the present invention, a spiral electrode assembly which can be preferably used for manufacturing a secondary battery for an electric vehicle having a large energy density, a small resistance heat generation and a good earthquake resistance. The body can be provided with good productivity and low cost.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing an example of a comb-shaped current collecting tab used in a spiral electrode assembly according to the present invention.

FIG. 2 is a plan view schematically showing a strip electrode used in a spiral electrode assembly according to the present invention.

FIG. 3 is a schematic plan view showing a state in which a comb-shaped current collecting tab is seam-welded to one side edge along a length direction of a strip-shaped electrode according to the present invention.

FIG. 4 is a schematic view showing an example of a process of assembling a spiral electrode assembly according to the present invention.

FIG. 5 is a schematic cross-sectional view for explaining a step of seam welding a comb-shaped current collecting tab to a strip electrode according to the present invention.

FIG. 6 is a schematic cross-sectional view illustrating an example of a secondary battery formed using the spiral electrode assembly according to the present invention.

FIG. 7 is a schematic plan view illustrating a strip electrode and a plurality of individual metal plate leads used to form a spiral electrode assembly according to the prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Strip-shaped positive electrode 1a Strip-shaped positive electrode current collector 1b Positive electrode active material 2 Strip-shaped negative electrode 2a Strip-shaped negative electrode current collector 2b Negative electrode active material 3a, 3b Individual metal plate leads 4A, 4B Comb-shaped current collecting tabs 4A1, 4B1 Continuous metal tape portion 4A2, 4B2 Metal protrusion 5 Strip separator 6A, 6B Seam welder 7 Spiral electrode assembly 8 Welding power supply 10 Negative electrode can 11 Positive electrode terminal 12 Electrically insulating gasket

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryuji Oshita 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Kazunari Ohita Keihan-hondori, Moriguchi-shi, Osaka 2-5-5 Sanyo Electric Co., Ltd. (72) Inventor Yoshito Chino 2-5-5 Sanyo Electric Co., Ltd. Sanyo Electric Co., Ltd. (72) Inventor Toshiyuki Noma Moriguchi, Osaka 2-5-5 Keihan Hondori Sanyo Electric Co., Ltd. (72) Inventor Ikuro Yonezu 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Koji Nishio Osaka 2-5-5 Keihanhondori, Moriguchi City Sanyo Electric Co., Ltd.

Claims (3)

[Claims] 1. A belt-shaped positive electrode in which a positive electrode active material is adhered on a positive electrode current collector of a band-shaped metal foil, and a band-shaped electrode in which a negative electrode active material is adhered on a negative electrode current collector of a band-shaped metal foil. A spiral electrode assembly formed by winding a negative electrode and a separator on each other with a separator interposed therebetween, and a positive electrode comb-shaped current collecting tab for guiding current from each of the positive electrode current collector and the negative electrode current collector; A negative electrode comb-shaped current collecting tab, wherein each of the comb-shaped current collecting tabs has a continuous metal tape portion and a plurality of metal protrusions protruding in a comb shape from one side edge along the length direction of the tape portion; And the tape portion of each of the positive electrode comb current collector tab and the negative electrode comb current collector tab is one side along a length direction of a corresponding one of the positive electrode current collector and the negative electrode current collector Seam welded to the edge, and the positive comb current collecting tab Serial the projecting portion and the spiral electrode assembly, wherein the secondary battery spiral type electrode assembly that are protruded in opposite directions from both end surfaces of the of the negative electrode comb collecting tab and the projecting portion. 2. The method according to claim 1, wherein the plurality of protruding portions of the comb-shaped current collecting tab are formed at intervals of not more than three times a width of the band-shaped current collector along a length direction of the tape portion. A spiral electrode assembly for a secondary battery according to claim 1. 3. The spiral electrode assembly for a secondary battery according to claim 1, wherein the secondary battery is used for an electric vehicle.