KR20210063150A - Rechargeable battery manufacturing method and rechargeable battery - Google Patents

Abstract

The present invention relates to a method for manufacturing a secondary battery to increase output performance of the secondary battery and a secondary battery thereof. According to the present invention, an electrolyte supply apparatus for a secondary battery performs: a first injection step of injecting a primary electrolyte into a battery case in which an electrode assembly is accommodated; an activation step of applying electricity to the electrode assembly and activating the same through charging and discharging; a secondary injection step of injecting a secondary electrolyte into the battery case after the activation step; and a sealing step of sealing the battery case after the second injection step. The first electrolyte includes a first salt, a non-nitrile-based first solvent, and a first additive. The second electrolyte includes a second solvent including a nitrile-based solvent, wherein the nitrile-based solvent is mixed in an amount of 30 vol% or less of the summed amount of the first solvent and the second solvent.

Description

Secondary battery manufacturing method and secondary battery {RECHARGEABLE BATTERY MANUFACTURING METHOD AND RECHARGEABLE BATTERY}

The present invention relates to a secondary battery manufacturing method and secondary battery.

Secondary batteries, unlike primary batteries, are rechargeable, and have been widely researched and developed in recent years due to their small size and large capacity. As technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing.

The secondary battery is classified into a coin-type battery, a cylindrical battery, a prismatic battery, and a pouch-type battery according to the shape of the battery case. In a secondary battery, an electrode assembly mounted inside a battery case is a charging/discharging power generating element having a stacked structure of electrodes and a separator.

The electrode assembly is a sheet-type electrode assembly coated with an active material, with a separator interposed between the positive electrode and the negative electrode, and is of a jelly-roll type, and a plurality of positive and negative electrodes are sequentially stacked with a separator interposed therebetween. , and stacked unit cells can be roughly classified into a stack/folding type in which a long-length separation film is wound. The double jelly roll type electrode assembly is widely used because it is easy to manufacture and has the advantage of high energy density per weight.

When manufacturing a lithium secondary battery, when drying of the electrode assembly located in the exterior material is completed, the electrolyte is injected at once and then sealed to complete the injection process.

One of the most effective ways to improve the output performance of a lithium secondary battery is to increase the ionic conductivity of the electrolyte. For this purpose, a solvent having a light molecular structure and low viscosity should be mainly used.

However, a nitrile-based solvent having a light molecular structure and low viscosity has a problem of eluting copper (Cu) in the range of 2.8 to 3.0V.

In general, in the case of an anode to which a graphite-based anode active material is applied, when the cell is not activated, the potential is approximately ~3V, and a nitrile-based solvent with a light molecular structure and low viscosity is applied to the electrolyte. In this case, there is a problem of causing copper elution from the negative electrode current collector during the wetting process after the injection.

Korean Patent Publication No. 10-1997-0054729

One aspect of the present invention is to provide a secondary battery manufacturing method and secondary battery capable of improving the copper eluting problem after pouring electrolyte into the battery case in which the electrode assembly is accommodated, and improving battery output performance.

A secondary battery manufacturing method according to an embodiment of the present invention includes a primary injection step of injecting a primary electrolyte into a battery case in which an electrode assembly is accommodated, and an activation step of applying electricity to the electrode assembly and activating it through charging and discharging. and a second injection step of injecting a secondary electrolyte into the inside of the battery case after the activation step, and a sealing step of sealing the battery case after the second injection step, wherein the first electrolyte solution Silver includes a first salt, a non-nitrile-based first solvent, and a first additive, and the secondary electrolyte is a second solvent including a nitrile-based solvent. including, wherein the secondary electrolyte may be mixed in an amount of 30 vol% or less of the total amount of the nitrile-based solvent of the first solvent and the second solvent.

Meanwhile, the secondary battery according to the embodiment of the present invention may be manufactured according to the method for manufacturing the secondary battery according to the embodiment of the present invention.

According to the present invention, when manufacturing a lithium secondary battery, the electrolyte solution containing a non-nitrile-based solvent is first injected before the activation step to prevent or significantly reduce copper elution from the anode current collector, and after the activation step By secondary injection of an electrolyte containing a nitrile-based solvent with a light molecular structure and low viscosity, the ionic conductivity of the electrolyte can be increased to improve the output performance of the secondary battery.

1 is a plan view illustrating a state before an electrode assembly is accommodated in a method for manufacturing a secondary battery according to an embodiment of the present invention.
2 is a plan view illustrating a first injection step in a method for manufacturing a secondary battery according to an embodiment of the present invention.
3 is a plan view illustrating a sealing step in a method for manufacturing a secondary battery according to an embodiment of the present invention.
4 is a plan view illustrating a de-gas step in a method for manufacturing a secondary battery according to an embodiment of the present invention.
5 is a plan view illustrating a secondary injection step in the method for manufacturing a secondary battery according to an embodiment of the present invention.
6 is a plan view illustrating a sealing step in a method for manufacturing a secondary battery according to an embodiment of the present invention.
7 is a graph showing discharge evaluation of secondary batteries prepared in Examples 1 and 2 and Comparative Example 1. FIG.
8 is a graph showing initial capacity evaluation of secondary batteries prepared in Examples 1 and 2 and Comparative Example 2. FIG.

Objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the accompanying drawings. In adding reference numerals to elements of each drawing in the present specification, it should be noted that, even though they are indicated on different drawings, only the same elements are to have the same number as possible. In addition, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. And, in describing the present invention, detailed descriptions of related known technologies that may unnecessarily obscure the gist of the present invention will be omitted.

1 is a plan view showing a state before the electrode assembly is accommodated in the secondary battery manufacturing method according to an embodiment of the present invention, and FIG. 2 is a plan view showing the first injection step in the secondary battery manufacturing method according to the embodiment of the present invention. , Figure 3 is a plan view showing a sealing step in the secondary battery manufacturing method according to an embodiment of the present invention.

In addition, FIG. 4 is a plan view showing a de-gas step in the method for manufacturing a secondary battery according to an embodiment of the present invention, and FIG. 5 is a second injection step in the method for manufacturing a secondary battery according to an embodiment of the present invention. 6 is a plan view showing a sealing step in a method for manufacturing a secondary battery according to an embodiment of the present invention.

1, 2, 5, and 6 , the secondary battery manufacturing method according to an embodiment of the present invention includes injecting a primary electrolyte into the battery case 120 in which the electrode assembly 110 is accommodated. A secondary injection step, an activation step of applying electricity to the electrode assembly 110 and activating it through charging and discharging, a secondary injection step of injecting a secondary electrolyte into the battery case 120, and the battery case 120 It is possible to manufacture the secondary battery 100, including the sealing step of sealing the. In addition, referring to FIGS. 1, 3 and 4 , the method for manufacturing a secondary battery according to an embodiment of the present invention includes an aging step in which a predetermined time elapses so that the electrode assembly 110 is impregnated in an electrolyte solution, and before the aging step A sealing step of sealing the open portion of the battery case 120 to form a sealing part S1, and a de-gas for discharging the internal gas of the battery case 120 to the outside by cutting the sealing part S1 ) may be further included.

Referring to FIG. 1 , the secondary battery 100 includes a battery case 120 and an electrode assembly 110 accommodated in a receiving part 121 of the battery case 120 . In this case, the electrode assembly 110 may include electrode leads 111 and 112 electrically connected to the electrode.

The electrode assembly 110 is a power generating element capable of charging and discharging, and may be formed by alternately stacking electrodes and separators.

The electrode may be composed of an anode and a cathode. In this case, the electrode assembly 110 may have a structure in which anode/separator/cathode are alternately stacked. In addition, the electrode lead leads 111 and 112 may include a positive electrode lead 111 connected to the positive electrode and a negative electrode lead 112 connected to the negative electrode.

The positive electrode may include a positive electrode current collector and a positive electrode active material stacked on the positive electrode current collector.

The positive electrode current collector may be made of an aluminum foil.

The cathode active material may be formed of lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a compound or mixture containing at least one of them.

The negative electrode may include a negative electrode current collector and a negative electrode active material laminated on the negative electrode current collector.

The negative electrode current collector may be made of, for example, a foil made of a copper (Cu) material.

The negative active material may be a compound or mixture including a graphite-based material.

The separator is made of an insulating material and electrically insulates between the anode and the cathode. Here, the separator may be formed of a polyolefin-based resin film such as polyethylene or polypropylene having microporosity.

Referring to FIG. 2 , in the first injection step, the primary electrolyte may be injected into the battery case 120 in which the electrode assembly is accommodated. At this time, the primary electrolyte may be injected into the battery case 120 through the electrolyte supply pipe (P).

The primary electrolyte may include a first salt, a non-nitrile-based first solvent, and a first additive.

The first salt may include at least one of LiPF6, LiTFSI, LiFSI, and LiBOB.

The first solvent is at least one of ethylene carbonate (EC), polycarbonate (PC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl acetate (EA), and ethyl propionate (EP). It may include more than one.

The first additive may include at least one of vinylene carbonate (VC), fluoro ethylene carbonate (FEC), propane sultone (PS), ethylene sulfite (Esa), and LiBF 4 . That is, a stable SEI (Solid Electrolyte Interphase) film may be formed on the surface of the anode active material by using VC, FEC, PS, Esa, LiBF4, etc., which are helpful in forming a stable SEI as the first additive. Accordingly, the SEI film positioned on the surface of the anode active material acts as a kinetic barrier to prevent further reduction reaction, thereby preventing or significantly reducing the occurrence of a decrease in the lifespan of the battery. In particular, it is possible to prevent an increase in cell resistance and a decrease in cycle life due to the stacking of layers of dead lithium and porous, which are caused by the repetition of the collapse and creation of the SEI film. can

Referring to FIG. 3 , in the sealing step, after the first injection step and before the aging step, the sealing part S1 may be formed by sealing the open portion of the battery case 120 .

In this case, the open portion may be sealed by thermally sealing the end of the gas pocket portion 122 in the battery case 120 .

In the aging step, after the first injection step and before the activation step, a predetermined time may elapse so that the electrode assembly is impregnated in the first electrolyte.

Accordingly, the electrode assembly may be completely immersed in the primary electrolyte to facilitate movement of lithium ions.

Referring to FIG. 4 , in the de-gas step, after the activation step and before the second injection step, the sealing part S1 may be cut to discharge the gas inside the battery case 120 to the outside.

At this time, the sealing part S1 formed at the end of the gas pocket part 122 in the battery case 120 is cut and removed using a cutter, etc., and the battery case (S1) is cut through the cut part of the gas pocket part 122. 120) can be discharged to the outside.

In the activation step, electricity is applied to the electrode assembly and may be activated through charging and discharging.

In this case, the secondary battery 100 may be activated through the activation step.

Referring to FIG. 5 , in the secondary injection step, the secondary electrolyte may be injected into the battery case 120 after the activation step. At this time, the secondary electrolyte may be injected into the battery case 120 through the electrolyte supply pipe (P).

The secondary electrolyte may include a second solvent including a nitrile-based solvent. Accordingly, as the secondary electrolyte containing a nitrile-based solvent having a light molecular structure and low viscosity is injected, the ionic conductivity of the electrolyte may be increased. At this time,

Accordingly, as the secondary electrolyte containing a nitrile-based solvent having a light molecular structure and low viscosity is injected into the battery case 120 after the activation step, the ionic conductivity of the electrolyte can be increased, and copper Elution can be prevented or significantly reduced.

Meanwhile, the secondary electrolyte may further include a second salt and a second additive.

The nitrile-based solvent contained in the secondary electrolyte may be mixed in an amount of 30 vol% or less of the combined content of the first solvent and the second solvent. Here, the secondary electrolyte may be mixed in an amount of 5 to 30 vol% of a nitrile-based solvent of the sum of the first solvent and the second solvent. In particular, in the secondary electrolyte, a nitrile-based solvent may be mixed in an amount of 10 to 30 vol% of the combined content of the first solvent and the second solvent.

The nitrile-based solvent may include any one or more of Acetonitrile (acetonitrile, acetonitrile), Propionitrile (propionitrile), (butyronitrile) butyronitrile, and Acrylic Acid Nitrile (nitrile acrylic acid).

Here, the nitrile (Nitrile)-based solvent may be made of propionitrile (propionitrile).

The second salt may include at least one of LiPF6, LiTFSI, LiFSI, and LiBOB.

The second additive may further include at least one of FB (fluorobenzene), VC (vinylene carbonate), FEC (fluoro ethylene carbonate), PS (propane sultone), Esa (ethylene sulfite), and LiBF4. have. Here, the second additive may include, for example, FB (fluorobenzene). Meanwhile, as another example, the second additive may include VC (vinylene carbonate) which helps to form SEI.

Referring to FIG. 6 , in the sealing step, the battery case 120 may be sealed after the second injection step.

In addition, in the sealing step, the gas pocket portion 122 is cut and removed, and then the removed portion is heat-sealed to form a sealing portion S2 to seal the battery case 120 .

<Example 1>

After the electrode assembly was accommodated in the battery case, a primary electrolyte including a first salt, a non-nitrile-based first solvent, and a first additive was injected. Here, as the primary electrolyte, 1.2M of LiPF6 was used as the first salt, and 3wt% of VC was used as the first additive. And EC, DMC, and EMC were used as the first solvent. Here, as the first solvent, 25,5,60 vol% of EC, DMC, and EMC were used for the entire first solvent and the second solvent, respectively. That is, the first solvent has a composition made by subtracting only EC, DMC, and EMC from EC/DMC/EMC/Propionitrile = 25/5/60/10 vol% which is the total composition of the first solvent and the second solvent. After the elapsed time, electricity was applied to the electrode assembly and activation was performed through charging and discharging.

And after 3 days of aging step, after opening the battery case through a partial incision, a second solvent (Solvent) containing a second salt, a nitrile (Nitrile) series solvent inside the battery case (Solvent), and a second additive A secondary electrolyte containing Here, as the secondary electrolyte, 1.2M of LiPF6 was used as the second salt, and 3wt% of VC was used as the second additive. And as the second solvent, Propionitrile was used, but 10 vol% of Propionitrile was used with respect to the entire first solvent and the second solvent. That is, the second solvent has a composition corresponding to 10 vol% of Propionitrile among the total composition of the first solvent and the second solvent, EC/DMC/EMC/Propionitrile = 25/5/60/10 vol%.

Thereafter, 3 days elapsed to manufacture a secondary battery.

<Example 2>

After the electrode assembly was accommodated in the battery case, a primary electrolyte including a first salt, a non-nitrile-based first solvent, and a first additive was injected. Here, as the primary electrolyte, 1.2M of LiPF6 was used as the first salt, and 3wt% of VC was used as the first additive. And EC, DMC, and EMC were used as the first solvent. Here, as the first solvent, 20,5,45 vol% of EC, DMC, and EMC were respectively used with respect to the entire first solvent and the second solvent. That is, the first solvent has a composition made by subtracting only EC, DMC, and EMC from the total composition of the first solvent and the second solvent, EC/DMC/EMC/Propionitrile = 20/5/45/30 vol%.

Thereafter, after 3 days had elapsed, electricity was applied to the electrode assembly to activate the electrode assembly through charging and discharging.

And after 3 days of aging step, after opening the battery case through a partial incision, a second solvent (Solvent) containing a second salt, a nitrile (Nitrile) series solvent inside the battery case (Solvent), and a second additive A secondary electrolyte containing Here, as the secondary electrolyte, 1.2M of LiPF6 was used as the second salt, and 3wt% of VC was used as the second additive. And propionitrile was used as the second solvent. At this time, 30 vol% of propionitrile was used with respect to the total of the first solvent and the second solvent. That is, the second solvent has a composition corresponding to 30 vol% of Propionitrile among EC/DMC/EMC/Propionitrile = 20/5/45/30 vol% which is the total composition of the first solvent and the second solvent.

Thereafter, 3 days elapsed to manufacture a secondary battery.

<Comparative Example 1>

After the electrode assembly was accommodated in the battery case, an electrolyte solution including a salt, a non-nitrile-based solvent, and an additive was injected. Here, LiPF6 1.2M as an electrolyte and 3 wt% of VC as an additive were used. And as for the solvent, 25,5,70 vol% of EC, DMC, and EMC were used with respect to the entire solvent.

Thereafter, after 3 days had elapsed, electricity was applied to the electrode assembly and activated by charging and discharging to manufacture a secondary battery.

<Comparative Example 2>

After the electrode assembly was accommodated in the battery case, a primary electrolyte including a first salt, a non-nitrile-based first solvent, and a first additive was injected. Here, as the primary electrolyte, 1.2M of LiPF6 was used as the first salt, and 3wt% of VC was used as the first additive. And EC, DMC, and EMC were used as the first solvent. Here, as the first solvent, 25,5,30 vol% of EC, DMC, and EMC were respectively used with respect to the entire first solvent. That is, the first solvent has a composition made by subtracting only EC, DMC, and EMC from the total composition of the first solvent and the second solvent, EC/DMC/EMC/Propionitrile = 25/5/30/40 vol%.

Thereafter, after 3 days had elapsed, electricity was applied to the electrode assembly to activate the electrode assembly through charging and discharging.

And after 3 days of aging step, after opening the battery case through a partial incision, a second solvent (Solvent) containing a second salt, a nitrile (Nitrile) series solvent inside the battery case (Solvent), and a second additive A secondary electrolyte containing Here, as the secondary electrolyte, 1.2M of LiPF6 was used as the second salt, and 3wt% of VC was used as the second additive. And propionitrile was used as the second solvent. In this case, 40 vol% of propionitrile was used with respect to the total amount of the first solvent and the second solvent. That is, the second solvent has a composition corresponding to 40 vol% of propionitrile among the total composition of the first solvent and the second solvent, EC/DMC/EMC/Propionitrile = 25/5/30/40 vol%.

Thereafter, 3 days elapsed to manufacture a secondary battery.

< Comparative Example 3 >

After the electrode assembly was accommodated in the battery case, a secondary battery was prepared by injecting an electrolyte including a salt, a nitrile-based solvent, and a first additive. Here, LiPF6 1.2M as an electrolyte and 3 wt% of VC as an additive were used. And as for the solvent, EC, DMC, EMC, and Propionitrile were used in 25,5,60,10 vol% of the entire solvent, respectively.

<Experimental Example 1>

7 is a graph showing discharge evaluation of secondary batteries prepared in Examples 1 and 2 and Comparative Example 1. FIG.

Discharge was evaluated at -10℃, SOC 50 (initial charge capacity 50%) state, 5C rate, and battery capacity at 1100mAh level.

Experimental results Referring to FIG. 7 , Example 1 (B) in which a secondary electrolyte containing 10 vol% of a nitrile-based solvent was injected than Comparative Example 1 (A) in which an electrolyte solution without using a nitrile-based solvent was injected and a nitrile-based solvent In Example 2 (C) in which the secondary electrolyte containing 30 vol% was injected, it was confirmed that the output performance of the secondary battery was significantly improved (resistance reduced).

Here, when referring to the graph of FIG. 7 , the resistance in Example 1 (B) was reduced by about 40 mohm compared to Comparative Example 1 (A), and the resistance was about 80 mohm in Example 2 (C) than in Comparative Example 1 (A). It can be seen that a decrease

<Experimental Example 2>

8 is a graph showing initial capacity evaluation of secondary batteries prepared in Examples 1 and 2 and Comparative Example 2;

Initial capacity was evaluated at 25 ℃, 0.33C rate.

Experimental results Referring to FIG. 8, in the graph of FIG. 8, Example 1 (B) in which the secondary electrolyte containing 10 vol% of the nitrile-based solvent was injected and Example 1 (B) in which the secondary electrolyte containing 30 vol% of the nitrile-based solvent was injected While the initial capacity of 2(C) is about 1180 to 1190 mAh, it can be seen that the initial capacity of Comparative Example 2(D) in which the secondary electrolyte containing 40 vol% of the nitrile-based solvent is injected is reduced to 1130 to 1140 mAh.

That is, when referring to FIG. 8, Example 1 (B) in which the secondary electrolyte containing 10 vol% of the nitrile-based solvent was injected and Example 2 (C) in which the secondary electrolyte containing 30 vol% of the nitrile-based solvent was injected. It can be seen that the initial capacity was reduced in Comparative Example 2(D) in which the secondary electrolyte containing 40 vol% of the nitrile-based solvent was injected, and from this, the comparative example in which the secondary electrolyte containing 40 vol% of the nitrile-based solvent was injected. It can be seen that 2(D) deteriorates from the initial capacity.

<Experimental Example 3>

In Comparative Example 3, the solution ICP was analyzed 3 days after the electrolyte injection, and in Example 1, the solution ICP was analyzed 3 days after the secondary electrolyte injection.

As a result of solution ICP analysis, in Comparative Example 3, about 360 (mg/kg) of copper was detected, whereas in Example 1, less than (5 mg/kg) of copper was detected.

That is, compared to Comparative Example 3 in which an electrolyte containing a nitrile-based solvent is injected into the battery case before charging and discharging, a primary electrolyte containing a non-nitrile-based solvent is injected before the activation step, and a nitrile-based solvent is injected after the activation step 2 It can be seen that in Example 1 in which the primary electrolyte was injected, copper elution was significantly reduced.

Although the present invention has been described in detail through specific examples, this is for the purpose of describing the present invention in detail, and the electrolyte supply apparatus and electrolyte supply method for a secondary battery according to the present invention are not limited thereto. It will be said that various implementations are possible by those of ordinary skill in the art within the technical spirit of the present invention.

In addition, the specific protection scope of the invention will become clear by the appended claims.

100: secondary battery
110: electrode assembly
111: positive lead
112: negative lead
120: battery case
121: receptacle
122: gas pocket portion
P: Electrolyte supply pipe
S1: sealing part
S2: seal

Claims (12)

a first injection step of injecting a primary electrolyte into the battery case in which the electrode assembly is accommodated;
an activation step of applying electricity to the electrode assembly and activating it through charging and discharging;
a secondary injection step of injecting a secondary electrolyte into the inside of the battery case after the activation step; and
and a sealing step of sealing the battery case after the second injection step,
The first electrolyte includes a first salt, a non-nitrile-based first solvent, and a first additive,
The secondary electrolyte includes a second solvent including a nitrile-based solvent,
The secondary electrolyte is a secondary battery manufacturing method in which the nitrile-based solvent is mixed in an amount of 30 vol% or less of the sum of the first solvent and the second solvent. The method according to claim 1,
The secondary electrolyte is a secondary battery manufacturing method in which the nitrile-based solvent is mixed in an amount of 5 to 30 vol% of the sum of the first solvent and the second solvent. The method according to claim 1,
The nitrile (Nitrile) solvent is Acetonitrile (acetonitrile, acetonitrile), Propionitrile (propionitrile), (butyronitrile) butyronitrile and Acrylic Acid Nitrile (Acrylic Acid Nitrile) Secondary battery manufacturing method comprising at least one of . The method according to claim 1,
The nitrile (Nitrile)-based solvent is a secondary battery manufacturing method comprising propionitrile (propionitrile). The method according to claim 1,
The first salt is a secondary battery manufacturing method comprising at least one of LiPF6, LiTFSI, LiFSI, and LiBOB. The method according to claim 1,
The first solvent is at least one of ethylene carbonate (EC), polycarbonate (PC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl acetate (EA), and ethyl propionate (EP). A secondary battery manufacturing method comprising any one or more. The method according to claim 1,
The first additive is a secondary battery manufacturing method comprising at least any one of VC (vinylene carbonate), FEC (fluoro ethylene carbonate), PS (propane sultone), Esa (ethylene sulfite), LiBF4. The method according to claim 1,
The secondary electrolyte further comprises a second salt (Salt),
The second salt (Salt) is a secondary battery manufacturing method comprising at least one of LiPF6, LiTFSI, LiFSI, and LiBOB. The method according to claim 1,
The secondary electrolyte further comprises a second additive,
The second additive is a secondary battery manufacturing method comprising FB (fluorobenzene). The method according to claim 1,
After the first injection step, before the activation step
The secondary battery manufacturing method further comprising an aging step of allowing a predetermined time to elapse so that the electrode assembly is impregnated in the primary electrolyte. The method of claim 10,
a sealing step of sealing an open portion of the battery case to form a sealing part after the first injection step and before the aging step; and
After the activation step and before the secondary injection step, the secondary battery manufacturing method further comprising a degas (De-gas) step of discharging the gas inside the battery case to the outside by cutting the sealing part. A secondary battery manufactured by the secondary battery manufacturing method according to any one of claims 1 to 11.

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