[One]Cross Citation with Related Applications
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0040973 on April 08, 2019, and all contents disclosed in the documents of the Korean patent application are incorporated as a part of this specification.
[3]
technical field
[4]
The present invention relates to a secondary battery and a method for manufacturing the same, and more particularly, to a secondary battery that prevents precipitation due to irregular coatings occurring during coating of an electrode active material, and a manufacturing method thereof.
background
[5]
In general, a secondary battery refers to a battery that can be charged and discharged, unlike a primary battery that cannot be charged, and such secondary batteries are widely used in the field of advanced electronic devices such as phones, notebook computers, and camcorders.
[6]
Such a secondary battery includes an electrode assembly in which electrodes and separators are alternately stacked, and a case accommodating the electrode assembly, and the electrode assembly has a structure in which a plurality of electrodes and a plurality of separators are alternately stacked.
[7]
Here, the plurality of electrodes includes a first electrode and a second electrode, the first electrode includes a first current collector, a first electrode active material coated on the first current collector, and the second electrode includes a second electrode It includes a current collector and a second electrode active material coated on the second current collector.
[8]
Meanwhile, the first electrode is an anode, and the second electrode is a cathode.
[9]
The method for manufacturing a secondary battery having such a configuration includes an electrode manufacturing step of manufacturing a first electrode and a second electrode, and an electrode assembly manufacturing step of manufacturing an electrode assembly by stacking the first and second electrodes with a separator interposed therebetween Including, wherein the electrode manufacturing step is a first electrode manufacturing process of manufacturing the first electrode by applying a first active material from the coating start portion of the first current collector to the coating end portion, and coating at the coating start portion of the second current collector and a second electrode manufacturing process of manufacturing a second electrode by applying a second active material to the distal end.
[10]
Here, the first electrode manufacturing process is irregular while a large amount of the first active material is coated on any one of the coating start part and the coating end part of the first current collector in the process of applying the first active material from the coating start part to the coating end part of the first current collector There was a problem in that a coating part, that is, a balcony (hump) was generated, and precipitation occurred on the second electrode, which is a negative electrode, due to the balcony, and as a result, there was a problem in that safety and battery performance were deteriorated.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[11]
The present invention was invented to solve the above problems, and the present invention forms an inactive coating part covering the irregular coating part generated on the first electrode, which is an anode, on a second electrode, which is a negative electrode, and, accordingly, irregularities generated on the first electrode. It is to provide a secondary battery capable of stably covering the coating portion, and as a result, it is possible to prevent precipitation from occurring on the second electrode, and in particular to improve safety and battery performance, and a method for manufacturing the same.
means of solving the problem
[12]
A secondary battery of the present invention for achieving the above object includes a first current collector, a first electrode having a first electrode active material coated on at least one surface of the first current collector; and a second electrode including a second current collector and a second electrode active material coated on at least one surface of the second current collector, wherein at least one of a coating start portion and an end portion of the first electrode active material has a first electrode active material The irregularly increased coated irregular coating portion may be formed, and an inactive coating portion covering the irregular coating portion may be formed on at least one of the coating start portion and the end portion of the second electrode active material.
[13]
The inert coating part may be formed of the same material as the second electrode active material.
[14]
The inert coating portion may be formed by extending and coating at least one of a coating start portion and an end portion of the second electrode active material to cover the irregular coating portion.
[15]
The inert coating portion may be coated to be thicker than the thickness from the coating start portion to the coating end portion of the second electrode active material.
[16]
The inert coating portion may have a coating thickness corresponding to the irregular coating portion.
[17]
The first electrode may be an anode, and the second electrode may be a cathode.
[18]
The first electrode may further include an inert tape attached to the irregular coating portion.
[19]
The inert tape may be attached to cover the entire irregular coating portion.
[20]
On the other hand, in the secondary battery manufacturing method of the present invention, a first electrode active material is applied on one surface of a first current collector from a coating start portion to a coating end portion, and on the other surface of the first collector, from the coating start portion to the coating end portion, the first electrode A first electrode manufacturing step of manufacturing a first electrode by applying an active material (S10); and coating a second electrode active material on one surface of the second current collector from the coating start portion to the coating end portion, and coating the second electrode active material on the other surface of the second collector from the coating start portion to the coating end portion to prepare a second electrode and a second electrode manufacturing step (S20), wherein, in the first electrode manufacturing step (S10), an irregular coating portion is formed in at least one of the coating start portion and the coating end portion due to an increase in the loading amount of the first electrode active material, The second electrode manufacturing step (S20) may further form an inert coating portion covering the irregular coating portion on at least one of a coating start portion and a coating end portion of the second electrode active material.
[21]
In the second electrode manufacturing step (S20), after coating at least one of the coating start part and the coating end part of the second electrode active material, the loading amount of the second electrode active material is increased to coat the inert coating part covering the irregular coating part can do.
[22]
The inert coating portion may be coated thicker than the thickness from the coating start portion to the coating end portion of the second electrode active material.
[23]
The inert coating portion may be coated to a thickness corresponding to the irregular coating portion.
[24]
After the second electrode manufacturing step (S20), the electrode rolling step (S30) of rolling the surfaces of the first electrode and the second electrode may be further included.
[25]
After the electrode rolling step (S30), the method may further include a tape attachment step (S40) of attaching an inert tape to the irregular coating portion formed on the first electrode.
[26]
After the tape attaching step (S40), a secondary battery manufacturing step (S60) of manufacturing a secondary battery by interposing a separator between the first electrode and the second electrode may be further included.
Effects of the Invention
[27]
The secondary battery of the present invention is characterized in that an inactive coating portion is formed to cover the irregular coating portion generated on the first electrode when the second electrode, which is the negative electrode, is manufactured, and due to this characteristic, the irregular coating portion can be stably covered. It is possible to prevent the occurrence of precipitation on the second electrode, and as a result, it is possible to improve the safety and performance of the secondary battery.
Brief description of the drawing
[28]
1 is a perspective view showing a secondary battery according to a first embodiment of the present invention.
[29]
2 is a cross-sectional view illustrating an electrode assembly of a secondary battery according to a first embodiment of the present invention.
[30]
3 is a cross-sectional view illustrating an inactive tape of a secondary battery according to a first embodiment of the present invention.
[31]
4 is a flowchart illustrating a method for manufacturing a secondary battery according to a first embodiment of the present invention.
[32]
5 is a process diagram illustrating a method for manufacturing a secondary battery according to a first embodiment of the present invention.
[33]
6 is a measurement value of the thickness of the second electrode active material and the inactive coating portion of the second electrode manufactured by the method for manufacturing a secondary battery according to the first embodiment of the present invention.
[34]
7 is a graph showing the thickness before rolling and the thickness after rolling of the second electrode manufactured by the method for manufacturing a secondary battery according to the first embodiment of the present invention.
Best mode for carrying out the invention
[35]
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.
[36]
[Secondary battery according to the first embodiment of the present invention]
[37]
As shown in FIG. 1 , the secondary battery 100 according to the first embodiment of the present invention includes an electrode assembly 110 , and a can 120 accommodating the electrode assembly 110 and the can 120 . It includes a cap assembly 130 mounted on the opening of the.
[38]
As shown in FIG. 2 , the electrode assembly 110 has a structure in which a plurality of electrodes and a plurality of separators are alternately stacked, and the plurality of electrodes includes a first electrode 111 and a second electrode 112 . includes That is, the electrode assembly 110 includes a first electrode 111 and a second electrode 112 stacked from top to bottom and a separator 113 interposed between the first electrode 111 and the second electrode 112 . include
[39]
The first electrode 111 includes a first current collector 111a, and a first electrode active material 111b coated from the coating start portion (A) to the coating end portion (B) of the first current collector 111a. do.
[40]
The second electrode 112 includes a second current collector 112a, and a second electrode active material 112b coated from the coating start portion (C) to the coating end portion (D) of the second current collector 112a. do.
[41]
Here, the first electrode is an anode, and the second electrode is a cathode.
[42]
On the other hand, the first electrode 111, which is the positive electrode, from the coating start portion (A) to the coating end portion (B) of the first current collector 111a by using a coating device (not shown) in which the first electrode active material 111b is stored. Coating is carried out while applying the first electrode active material 111b, and at this time, the coating device moves uniformly between the coating start part (A) and the coating end part (B) except for the coating start part (A) and the coating end part (B). Therefore, the first electrode active material can be coated with a uniform thickness, but the coating start portion (A) and the coating end portion (B) start or finish the coating while the coating device is stopped, so the first electrode active material 111b ) is applied excessively, the irregular coating portion 111c is formed. That is, the irregular coating portion 111c is the first electrode active material 111b excessively applied to the coating start portion (A) and the coating end portion (B) of the first current collector 111a, as shown in FIG. 2 . is formed by
[43]
Since the irregular coating portion 111c formed in this way is an unintentional coating during the manufacture of the first electrode, when the first electrode 111 and the second electrode 112 are laminated, the irregular coating portion 111c causes the second electrode ( 112), lithium precipitation occurs, which may deteriorate safety and battery performance.
[44]
In order to solve the above problems, the second electrode 112 includes an inert coating part 112c covering the irregular coating part 111c generated on the first electrode 111, and the inert coating part 112c. Through this, it is possible to stably cover the irregular coating portion 111c, thereby preventing lithium precipitation on the electrode, and as a result, it is possible to prevent safety and deterioration of battery performance.
[45]
That is, the inert coating portion 112c is the coating start portion C of the second current collector 112a included in the second electrode 112 corresponding to the irregular coating portion 111c formed on the first electrode 111 . And it is formed on any one of the coating end portion (D), and thus the irregular coating portion 111c formed on the first electrode 111 can be covered with the inert coating portion 112c formed on the second electrode 112 .
[46]
Meanwhile, the inactive coating part 112c is formed of the same material as the second electrode active material 112b. That is, the inert coating portion 112c is formed of the same material as the second electrode active material 112b coated on the second current collector 112a, thereby increasing the ease of manufacture, and in particular, the inert coating portion 112c ) and the irregular coating portion 111c are unintentional coatings, but battery performance can be improved due to an increase in the active material.
[47]
In other words, the inactive coating portion 112c is coated with the second electrode active material 112b from the coating start portion (C) to the coating end portion (D) of the second collector 112a, at this time, the second collector ( The loading amount of the second electrode active material 112b at the coating start portion (C) and the coating end portion (D) of 112a) is increased, and accordingly, the second electrode coated on the coating start portion (C) and the coating end portion (D) As the active material 112b is spread widely, the inactive coating portion 112c is formed.
[48]
In summary, as the inert coating part 112c extends and coats at least one of the coating start part C and the end part D of the second electrode active material 112b to cover the irregular coating part 111c, Thus, the second electrode active material 112b and the inactive coating part 112c can be formed of the same material, and as a result, the ease of manufacture can be improved.
[49]
On the other hand, the inert coating portion 112c is coated to be thicker than the thickness from the coating start portion (C) to the coating end portion (D) of the second electrode active material 112b. That is, since the irregular coating portion 111c is generated due to an increase in the loading amount of the first electrode active material 111b, the inactive coating portion 112c is separated from the coating start portion C of the second electrode active material 112b to the coating end portion. The coating is thicker than the thickness up to (D), and thus the irregular coating portion 111c can be stably covered.
[50]
In particular, the inert coating portion 112c has a coating thickness corresponding to that of the irregular coating portion 111c. That is, when the inert coating part 112c has a smaller coating thickness than the irregular coating part 111c, the irregular coating part 111c cannot be stably covered through the inert coating part 112c, and thus the second electrode 112. precipitation may occur. In addition, when the inactive coating portion 112c has a greater coating thickness than the irregular coating portion 111c, it is possible to stably cover the irregular coating portion 111c, but manufacturing cost due to excessive use of the second electrode active material 112b expenditure can be significant. Accordingly, the inert coating portion 112c has a coating thickness corresponding to the irregular coating portion 111c, thereby reducing manufacturing cost and stably covering the irregular coating portion 111c.
[51]
On the other hand, the surface of the inactive coating part 112c corresponding to the irregular coating part 111c may be formed as a flat horizontal plane 112c-1, and thus, even if the surface of the irregular coating part 111c is irregularly formed, irregular coating The friction between the portion 111c and the inert coating portion 112c may be minimized, and the irregular coating portion 111c may be stably covered.
[52]
On the other hand, the connecting portion of the second electrode active material 112b and the inactive coating portion 112c is formed as an inclined surface 112c-2 so that a chin is not formed, and accordingly, the second electrode active material portion 112b and the inactive coating portion ( It is possible to prevent the separator 113 from being caught and damaged due to the connection part of 112c), and in particular, the irregular coating part 111c is caught on the connection part of the second electrode active material 112b and the inactive coating part 112c, and the first It is possible to prevent the electrode or the second electrode from being folded or damaged.
[53]
The secondary battery 100 according to the first embodiment of the present invention having such a configuration is characterized in that the second electrode 112, which is the negative electrode, includes an inactive coating part 112c. It is possible to stably cover the irregular coating portion 111c generated on the electrode 111, thereby preventing lithium precipitation from occurring on the second electrode 112, and as a result, increase stability and prevent deterioration of battery performance can do.
[54]
On the other hand, in the secondary battery 100 according to the first embodiment of the present invention, as shown in FIG. 3 , an inactive tape 114 attached to the irregular coating portion 111c formed on the first electrode 111 is applied. may include more. That is, when a meandering defect occurs in the first electrode 111 and the second electrode 112 stacked from top to bottom, the first electrode 111 and the second electrode 112 are stacked at different angles, and accordingly, The inactive coating part 112c of the second electrode 112 may not cover the irregular coating part 111c formed on the first electrode 111 . To prevent this, an inactive tape 114 is attached to the irregularly coated portion 111c formed on the first electrode 111 to cover the irregularly coated portion 111c, and accordingly, the first electrode 111 and the second electrode Even if the 112 is stacked at different angles, it is possible to stably cover the irregular coating portion 111c.
[55]
On the other hand, the inactive tape 114 is attached to completely surround the irregularly coated portion 111c, and thus the entire irregularly coated portion 111c can be stably covered.
[56]
On the other hand, the secondary battery 100 according to the first embodiment of the present invention has an adhesive 115 between the edge surface of the inactive tape 114 and the first electrode 111 in order to increase the adhesive force of the edge surface of the inactive tape 114 . is applied, and the adhesive force of the edge surface of the inactive tape 114 can be greatly increased through the adhesive 115 .
[57]
In particular, the inert tape may be formed of a double-sided tape, and accordingly, the irregularly coated portion 111c and the separator 113 may be attached to each other to be connected, and as a result, the irregularly coated portion 111c may be formed on the first electrode (111) to prevent meandering defects.
[58]
Hereinafter, a method for manufacturing a secondary battery according to a first embodiment of the present invention will be described.
[59]
[Method for manufacturing secondary battery according to the first embodiment of the present invention]
[60]
A secondary battery manufacturing method according to a first embodiment of the present invention includes a first electrode manufacturing step (S10) of manufacturing a first electrode 111 as shown in FIGS. 4 and 5; and a second electrode manufacturing step S20 of manufacturing the second electrode 112 .
[61]
First electrode manufacturing step
[62]
Referring to (a) of FIG. 5, the first electrode manufacturing step (S10) is a coating start part ( A first electrode active material 111b is applied from A) to the coating end portion (B). Next, the first electrode active material 111b from the coating start portion (A) to the coating end portion (B) on the other surface of the first current collector 111a (the bottom surface of the first current collector when viewed from (a) of FIG. 5). to apply Through this process, the first electrode 111 may be manufactured.
[63]
At this time, in the first electrode manufacturing step (S10), an irregular coating portion 111c is formed due to an increase in the loading amount of the first electrode active material 111b on at least one of the coating start portion A and the coating end portion B. .
[64]
Second electrode manufacturing step
[65]
Referring to (b) of FIG. 5, the second electrode manufacturing step (S20) is a coating start portion ( A second electrode active material 112b is applied from C) to the coating end portion (D). Next, the second electrode active material (112b) from the coating start portion (C) to the coating end portion (D) on the other surface of the second current collector 112a (the bottom surface of the second current collector as seen in FIG. 5(b)). to apply Through this process, the second electrode 112 may be manufactured.
[66]
At this time, the second electrode manufacturing step (S20) is an inert coating part ( 112c) is further formed. That is, in the second electrode manufacturing step (S20), the loading amount of the second electrode active material 112b when coating at least one of the coating start portion C and the coating end portion D of the second electrode active material 112b The inert coating part 112c covering the irregular coating part 111c is coated by increasing it.
[67]
In particular, in the second electrode manufacturing step (S20), the inert coating portion 112c is coated from the coating start portion (C) to the coating end portion (D) of the second electrode active material 112. The thickness of the second electrode active material 112b It is coated more thickly, so that it is possible to stably cover the irregular coating portion 111c. Moreover, the inert coating part 112c is coated to a thickness corresponding to the irregular coating part 111c, and thus the irregular coating part 111c can be stably covered.
[68]
Meanwhile, the method further includes an electrode rolling step (S30) of rolling the surfaces of the first electrode 111 and the second electrode 112 after the second electrode manufacturing step (S20).
[69]
electrode rolling step
[70]
In the electrode rolling step (S30), referring to FIG. 5(c), the first electrode 111 and the second electrode 112 are rolled using a rolling roll 20, and accordingly, the first electrode 111 The coating thicknesses of the first electrode active material 111b and the second electrode active material 112b of the second electrode 112 are uniformly adjusted.
[71]
In particular, in the electrode rolling step (S30), the excessively protruding irregular coating portion 111c and the inactive coating portion 112c covering it are also rolled together, and accordingly, the thickness of the irregular coating portion 111c and the inert coating portion 112c can reduce
[72]
After the electrode rolling step (S30), the method further includes a tape attachment step (S40) of attaching an inert tape to the irregular coating portion formed on the first electrode.
[73]
tape attachment step
[74]
In the tape attaching step ( S40 ), referring to FIG. 5 (d) , an inactive tape 114 is attached to surround the entire irregular coating portion 111c formed on the first electrode 111 . Then, even if a stacking error of the first and second electrodes 111 and 112 occurs, the irregular coating portion 111c may be stably covered through the inactive tape 114 .
[75]
On the other hand, the adhesive 115 is further applied to the boundary line between the inactive tape 114 and the irregular coating portion 111c, so that the adhesive force of the edge surface of the inactive tape 114 can be increased.
[76]
After the tape attaching step (S40), a secondary battery manufacturing step (S60) of completing the secondary battery 100 is further included.
[77]
Secondary battery manufacturing stage
[78]
In the secondary battery manufacturing step (S60), referring to FIG. 5(e), the electrode assembly 110 is manufactured by interposing a separator 113 between the first electrode 111 and the second electrode 112. .
[79]
And, as shown in FIG. 1 , the electrode assembly 110 is accommodated in the can 120 , and the cap assembly 130 is mounted in the opening of the can 120 to manufacture the secondary battery 100 .
[80]
At this time, as the irregular coating portion 111c formed on the first electrode 111 and the inactive coating portion 112c of the second electrode 112 are positioned to correspond to each other, the occurrence of precipitation on the second electrode 112 is prevented, as a result It is possible to increase safety and prevent deterioration of battery performance.
[81]
Experimental example
[82]
Three second electrodes, which are negative electrodes manufactured by the method for manufacturing a secondary battery of the present invention, are prepared, and the thickness and loading amount of the prepared second electrodes are measured, respectively. In particular, the thickness of the portion of the second electrode active material coated on the second electrode and the thickness of the portion of the inactive coating portion are measured.
[83]
In this case, the electrode thickness may be measured as high as about 30 μm, and the loading amount may be measured as high as about 20 mg/25 cm 2 . In addition, the nitrogen/phosphorus ratio may be increased from 104% to 110%, and the supply rate may be increased from 23.6% to 42.6% for the second electrode as the negative electrode compared to the first electrode as the positive electrode. This may prevent lithium precipitation on the second electrode even if an irregular coating portion is formed on the first electrode, which is the positive electrode.
[84]
Measurement result
[85]
As a result of the measurement as described above, an experimental table as shown in FIG. 6 can be obtained.
[86]
That is, when comparing the thickness and the loading amount of the three second electrodes 112 manufactured by the secondary battery manufacturing method of the present invention, the inert coating that is a single-sided coating part rather than the thickness and loading amount of the second electrode active material 112b, which is a double-sided coating part. It can be seen that the thickness and the loading amount of the portion 112c are large, and accordingly, the inactive coating portion 112c for covering the irregular coating portion 111c formed on the first electrode 111 can be stably formed.
[87]
In addition, Fig. 7 (a) shows the thickness before rolling of the three second electrodes 112 manufactured by the secondary battery manufacturing method of the present invention, and Fig. 7 (b) is the secondary battery manufacturing method of the present invention. It shows the thickness after rolling of the three second electrodes 112 manufactured by .
[88]
Referring to the graph of FIG. 7 , it can be seen that the thickness of the second electrode active material and the inactive coating portion coated on the second electrode 112 is reduced, and in particular, between the second electrode active material and the inactive coating portion is changed to a gentle slope. can be confirmed, and accordingly, it is possible to prevent the separator from being caught and damaged between the second electrode active material and the inactive coating part.
[89]
The scope of the present invention is indicated by the claims to be described later rather than the above detailed description, and various embodiments derived from the meaning and scope of the claims and their equivalent concepts are possible.

WE CLAIMS

a first current collector, a first electrode having a first electrode active material coated on at least one surface of the first current collector; and a second electrode including a second current collector and a second electrode active material coated on at least one surface of the second current collector, wherein at least one of a coating start portion and an end portion of the first electrode active material has a first electrode active material A secondary battery in which the irregularly increased coated irregular coating portion is formed, and an inactive coating portion covering the irregular coating portion is formed on at least one of the coating start portion and the end portion of the second electrode active material.
[Claim 2]
The secondary battery of claim 1 , wherein the inactive coating part is made of the same material as the second electrode active material.
[Claim 3]
The secondary battery of claim 1 , wherein the inert coating part is formed by extending and coating at least one of a coating start part and an end part of the second electrode active material to cover the irregular coating part.
[Claim 4]
The secondary battery of claim 1 , wherein the inert coating part is coated to be thicker than a thickness from a coating start portion to a coating end portion of the second electrode active material.
[Claim 5]
The secondary battery according to claim 1, wherein the inert coating part has a coating thickness corresponding to the irregular coating part.
[Claim 6]
The secondary battery of claim 1, wherein the first electrode is a positive electrode, and the second electrode is a negative electrode.
[Claim 7]
The secondary battery of claim 1 , wherein the first electrode further comprises an inert tape attached to the irregular coating part.
[Claim 8]
The secondary battery of claim 7 , wherein the inactive tape is attached to surround the entire irregular coating part.
[Claim 9]
The first electrode active material is applied to one surface of the first current collector from the coating start portion to the coating end portion, and the first electrode active material is applied to the other surface of the first collector from the coating start portion to the coating end portion to prepare a first electrode a first electrode manufacturing step (S10); and coating a second electrode active material on one surface of the second current collector from the coating start portion to the coating end portion, and coating the second electrode active material on the other surface of the second collector from the coating start portion to the coating end portion to prepare a second electrode and a second electrode manufacturing step (S20), wherein, in the first electrode manufacturing step (S10), an irregular coating portion is formed in at least one of the coating start portion and the coating end portion due to an increase in the loading amount of the first electrode active material, The second electrode manufacturing step (S20) is a secondary battery manufacturing method of further forming an inert coating portion covering the irregular coating portion on at least one of the coating start portion and the coating end portion of the second electrode active material.
[Claim 10]
The method according to claim 9, wherein the second electrode manufacturing step (S20), after coating at least one of the coating start portion and the coating end portion of the second electrode active material, by increasing the loading amount of the second electrode active material to cover the irregular coating portion A method of manufacturing a secondary battery for coating an inert coating part.
[Claim 11]
The method according to claim 10, wherein the inert coating portion is coated to be thicker than the thickness from the coating start portion to the coating end portion of the second electrode active material.
[Claim 12]
The method according to claim 10, wherein the inert coating portion is coated to a thickness corresponding to the irregular coating portion.
[Claim 13]
The method according to claim 9, further comprising an electrode rolling step (S30) of rolling the surfaces of the first electrode and the second electrode after the second electrode manufacturing step (S20).
[Claim 14]
The method according to claim 13, further comprising a tape attaching step (S40) of attaching an inert tape to the irregular coating portion formed on the first electrode after the electrode rolling step (S30).
[Claim 15]
The method according to claim 14, further comprising a secondary battery manufacturing step (S60) of manufacturing a secondary battery by interposing a separator between the first electrode and the second electrode after the tape attaching step (S40).