KR101584830B1 - Electrode assembly for secondary battery and secondary battery comprising the same - Google Patents

Abstract

An electrode assembly for a secondary battery and a secondary battery including the same are provided.
The electrode assembly for a secondary battery includes a positive electrode active material region provided with a positive electrode active material layer, a positive electrode tab region provided with a positive electrode tab, a positive electrode portion including a positive electrode uncoated region, and a negative electrode active material layer, A negative electrode portion including a negative electrode active material region, a negative electrode tab region provided with a negative electrode tab and facing the positive electrode uncoated region, and a negative electrode uncoated region facing the positive electrode tab region, And a separation part provided. The negative electrode portion may further include a negative electrode portion insulating resin layer covering the negative electrode tab and covering the negative electrode collector facing the positive electrode uncoated region.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electrode assembly for a secondary battery and a secondary battery including the electrode assembly.

The present invention relates to a secondary battery, and more particularly, to an electrode assembly for a secondary battery and a secondary battery including the same.

As technology development and demand increase, the performance of portable electronic products is continuously improving. Accordingly, the demand for a rechargeable secondary battery as an energy source for portable electronic products is rapidly increasing, and the level required for the performance of the secondary battery is also increasing. Among the secondary batteries, lithium secondary batteries which are small in size, large in capacity and free from memory phenomenon are the most popular. In the structure of the lithium secondary battery, an electrode assembly having electrodes, an electrolyte and a separator is integrated.

1 is a view for explaining an electrode assembly for a secondary battery according to the prior art. Referring to FIG. 1, the electrode assembly for a secondary battery includes an anode 10, a cathode 20, and a separator 30. The positive electrode 10 includes a positive electrode collector 11, a positive electrode active material layer 12 and a positive electrode tab 14. The negative electrode 20 includes a negative electrode collector 21, a negative electrode active material layer 22, 24).

A remnant of the positive electrode active material, for example, the positive electrode active material island 12r, may be formed in the positive electrode uncoated region where the positive electrode active material layer 12 of the positive electrode collector 11 is not provided. The cathode active material island 12r may contact the anode current collector 21 and an internal short circuit may occur. Also, the cathode active material of the cathode active material island 12r, for example, lithium may move to the cathode current collector 21 and lithium dendrite may be formed in the cathode current collector 21, thereby causing an internal short circuit .

According to the above-described problems, the secondary battery produced using the electrode assembly may increase the defective rate, shorten the service life, and reduce the productivity.

In order to solve the above problems, the present invention provides an electrode assembly for a secondary battery capable of preventing an internal short circuit.

The present invention provides a secondary battery including the electrode assembly for the secondary battery.

The electrode assembly for a secondary battery according to embodiments of the present invention is provided with a cathode active material layer provided with a cathode active material layer, a cathode tab region provided with a cathode tab, a cathode portion including an anode uncoated region, and a cathode active material layer A negative electrode portion including a negative electrode active material region facing the positive electrode active material region, a negative electrode tab region provided with a negative electrode tab and facing the positive electrode uncoated region, and a negative electrode uncoated region facing the positive electrode tab region, And a separator provided between the anode and the cathode. The negative electrode portion may further include a negative electrode portion insulating resin layer covering the negative electrode tab and covering the negative electrode collector facing the positive electrode uncoated region.

The anode portion may further include an anode portion insulating resin layer covering the edge of the cathode active material layer and the anode uncoated region.

Wherein the anode portion insulating resin layer and the cathode portion insulating resin insulating layer are made of a material selected from the group consisting of polyethylene terephthalate, polypropylene, polyester, polyphenylene sulfide, polyimide, acetate, glass fabric, polyvinylidene fluoride, A hexafluoropropylene copolymer, an epoxy resin, and a polyamide resin.

The negative electrode portion insulating resin layer may be provided on a portion of the negative electrode tab region opposed to the portion where the positive electrode portion insulating resin layer is not provided in the positive electrode uncoated region, The positive electrode portion insulating resin layer may be provided at a portion of the positive electrode non-coated portion opposite to the portion not provided with the negative electrode.

The width of the anode uncoated region may be 5 to 10 mm.

The cathode active material layer may include a lithium salt. The negative electrode active material layer may include at least one selected from natural graphite, artificial graphite, expanded graphite, carbon fiber, non-graphitizable carbon, carbon black, carbon nanotube, fullerene, and activated carbon.

The secondary battery according to embodiments of the present invention may include the electrode assembly for the secondary battery.

According to the embodiments of the present invention, the amount of the cathode active material remaining in the uncoated region can be reduced and the formation of the island of the cathode active material can be suppressed by making the uncoated region smaller than the conventional one. Even if the cathode active material island is formed on the first anode surface of the anode uncoated region, the anode active material is covered by the first insulating resin layer, or the opposing anode current collector is covered with the second insulating resin layer, It is possible to prevent the active material from contacting the negative electrode collector or moving to the negative electrode collector. As a result, the internal short circuit by the electrode assembly for the secondary battery can be prevented, the defect rate of the secondary battery can be reduced, the lifetime can be increased, and the productivity can be improved.

1 is a view for explaining an electrode assembly for a secondary battery according to the prior art.
2 is a view for explaining an electrode assembly for a secondary battery according to embodiments of the present invention.
3A to 3F are views for explaining a method of manufacturing an electrode assembly for a secondary battery according to embodiments of the present invention.

Hereinafter, the present invention will be described in more detail with reference to examples. The objects, features and advantages of the present invention will be easily understood by the following embodiments. The present invention is not limited to the embodiments described herein, but may be embodied in other forms. The embodiments disclosed herein are provided so that the disclosure may be thorough and complete, and that those skilled in the art will be able to convey the spirit of the invention to those skilled in the art. Therefore, the present invention should not be limited by the following examples.

Although the terms first, second, etc. are used herein to describe various elements, the elements should not be limited by these terms. These terms are only used to distinguish the elements from each other. Also, when an element is referred to as being on another element, it may be formed directly on the other element, or a third element may be interposed therebetween. In the drawings, the thicknesses of the layers, the tabs, the current collectors, the widths of the regions, and the like can be exaggerated for clarity. The sizes of the elements in the figures, or the relative sizes between the elements, may be exaggerated somewhat for a clearer understanding of the present invention. In addition, the shape of the elements shown in the drawings may be somewhat modified by variations in the manufacturing process or the like. Accordingly, the embodiments disclosed herein should not be construed as limited to the shapes shown in the drawings unless specifically stated, and should be understood to include some modifications. In this specification, the meaning of the A region and the B region facing each other means that the size of the overlapping portion of the A region and the B region is larger than the size of the overlapping portion of the A region or the B region opposite to the other C region .

2 is a view for explaining an electrode assembly for a secondary battery according to embodiments of the present invention.

Referring to FIG. 2, the electrode assembly for a secondary battery includes an anode 100, a cathode 200, and a separator 300. The anode part 100 and the cathode part 200 may be separated from each other by a separating part 300.

The anode portion 100 may include a cathode current collector 110, a cathode active material layer 120, a first insulating resin layer 130, and a cathode tab 140.

The anode current collector 110 may be a metal foil having excellent conductivity. The positive electrode collector 110 may include, for example, stainless steel, nickel, aluminum, titanium, or an alloy thereof. The surface of the anode current collector 110 may be surface-treated with carbon, nickel, titanium, or silver. The cathode current collector 110 may be, for example, an aluminum thin plate or an aluminum alloy thin plate. The anode current collector 110 may include a first anode surface 110a and a second anode surface 110b. The first anode surface 110a and the second anode surface 110b may extend in parallel with each other. The first anode surface 110a may face the separator 300.

A positive electrode active material layer 120 is provided on the positive electrode collector 110. The cathode active material layer 120 may include a first cathode active material layer 120a and a second cathode active material layer 120b. The first cathode active material layer 120a may be provided on the first anode surface 110a and the second cathode active material layer 120b may be provided on the second anode surface 110b. In this embodiment, both the first and second cathode active material layers 120a and 120b are provided, but in another embodiment, only one of the first and second cathode active material layers 120a and 120b is provided. .

The positive electrode active material layer 120 is, for example, _{LiCoO 2, LiMn 2 O 4,} LiNiO 2, Li x Ni 1-y Co y O 2 (0.9≤x≤1.2, 0 <y <1), Li x Ni a _{Co b Mn c O 2-y} M y (0.9≤x≤1.2, a + b + c = 1, 0≤y≤1, M is at least one halogen atom, or _{S), LiMnO 2, Li x} Fe 1- _{y Me y P z O 4-} a M a (0.9≤x≤1.2, 0≤y≤0.5, 0≤z≤1, 0≤a≤1, Me is Cr, Al, Mg, Mn, Co, and Ni And M may include at least one halogen element or S), etc., and a mixture of at least one of them.

A first insulating resin layer 130 covering the edge region of the cathode active material layer 120 is provided on the anode current collector 110. The first insulating resin layer 130 may be an insulating resin tape. The first insulating resin layer 130 is excellent in the insulation property, has excellent strength against the pressure, squeeze, and the impact upon dropping of the electrode when the electrode is wound, and excellent in stability against the non-aqueous electrolyte Do.

The first insulating resin layer 130 may be formed of, for example, a polyethylene terephthalate, a polypropylene, a polyester, a poly (phenylene sulfide), a polyimide, an acetate, a glass cloth, A vinylidene fluoride-hexafluoropropylene copolymer, an epoxy-based resin, and a polyamide-based resin, such as vinylidene and a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product.

The first insulating resin layer 130 may include a material having heat resistance. For example, the heat-resistant temperature and melting point of the first insulating resin layer 130 may be 150 ° C or higher. As a result, the first insulating resin layer 130 can stably perform its function as an insulating film even at a high temperature.

The heat-resistant material may have a high molecular weight and a high crystallinity, and examples thereof include polyvinylidene fluoride, a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a vinylidene fluoride-hexafluoropropylene copolymer , An epoxy resin, and a polyamide resin.

A positive electrode tab 140 is provided on the first positive electrode surface 110a of the positive electrode collector 110. [ The anode tab 140 may comprise, for example, aluminum.

The anode portion 100 may include a cathode active material region 100A, a cathode tab region 100B, and a cathode uncoated region 100C. The cathode active material region 100A represents a region where the cathode active material layer 120 is provided. The positive electrode active material layer 120 is provided on at least one of the first and second positive electrode surfaces 110a and 110b of the positive electrode collector 110 in the positive electrode active material region 100A. The positive electrode tab region 100B represents an area where the positive electrode tab 140 is provided in the region excluding the positive electrode active material region 100A in the positive electrode portion 100. [ The positive electrode uncoated region 100C represents a region of the positive electrode portion 100 excluding the positive electrode active material region 100A and the positive electrode tab region 100B. The positive electrode active material layer 120 and the positive electrode tab 140 are not provided in the positive electrode uncoated region 100C.

The cathode portion 200 may include an anode current collector 210, a cathode active material layer 220, a second insulating resin layer 230, and a cathode tab 240.

The anode current collector 210 may include, for example, stainless steel, nickel, copper, titanium, or an alloy thereof. The surface of the anode current collector 210 may be surface-treated with carbon, nickel, titanium, or silver. The anode current collector 210 may be, for example, a copper thin plate or a copper alloy thin plate. The anode current collector 210 may include a first cathode surface 210a and a second cathode surface 210b. The first cathode surface 210a and the second cathode surface 210b may extend in parallel with each other. The first cathode surface 210a may face the separator 300.

An anode active material layer 220 is provided on the anode current collector 210. The anode active material layer 220 may include a first anode active material layer 220a and a second anode active material layer 220b. The first anode active material layer 220a may be provided on the first cathode surface 210a and the second anode active material layer 220b may be provided on the second cathode surface 210b. In this embodiment, both the first negative electrode active material layer 220a and the second negative electrode active material layer 220b are provided, but in another embodiment, only one of the first and second negative electrode active material layers 220a and 220b is provided. .

The anode active material layer 220 may be formed of a mixture of carbon and graphite materials such as natural graphite, artificial graphite, expanded graphite, carbon fiber, hard graphitizable carbon, carbon black, carbon nanotube, fullerene, And mixtures of one or more.

A cathode tab 240 is provided on the first cathode surface 210a of the anode current collector 210. [ The negative electrode tab 240 may comprise, for example, nickel.

A second insulating resin layer 230 covering the cathode tab 240 is provided on the anode current collector 210. The second insulating resin layer 230 may be an insulating resin tape. The second insulating resin layer 230 is excellent in the insulating property, has excellent strength against the pressure, squeeze and the like which are received when the electrode is wound, strength against the impact upon dropping the battery, and excellent stability against the non-aqueous electrolyte Do.

The material of the second insulating resin layer 230 may be the same as or different from the material of the first insulating resin layer 130 and is not limited thereto as long as the present invention satisfies the requirements of the intended insulating resin layer. In addition, the first and second insulating resin layers 130 and 230 may have the same or different sizes. And the size thereof is not limited as long as it can achieve the object of preventing the occurrence of the cathode active material island. For example, the second insulating resin layer 230 attached on the negative electrode tab 240 may be longer or shorter than the first insulating resin layer 130. That is, if one of the first insulating resin layer 130 and the second insulating resin layer 230 is long, the other one may be provided short.

The second insulating resin layer 230 may be formed of, for example, polyethylene terephthalate, polypropylene, polyester, poly (phenylene sulfide), polyimide, acetate, glass cloth, A vinylidene fluoride-hexafluoropropylene copolymer, an epoxy-based resin, and a polyamide-based resin, such as vinylidene and a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product.

The second insulating resin layer 230 may include a material having heat resistance. For example, the heat-resistant temperature and melting point of the second insulating resin layer 230 may be 150 ° C or higher. Thus, the second insulating resin layer 230 can stably perform its function as an insulating film even at a high temperature.

The heat-resistant material may have a high molecular weight and a high crystallinity, and examples thereof include polyvinylidene fluoride, a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a vinylidene fluoride-hexafluoropropylene copolymer , An epoxy resin, and a polyamide resin.

The cathode portion 200 may include a cathode active material region 200A, a cathode tab region 200B, and a cathode uncoated region 200C. The negative active material region 100A represents a region where the negative active material layer 220 is provided. The negative electrode active material layer 220 is provided on at least one of the first and second negative electrode surfaces 210a and 210b of the negative electrode collector 210 in the negative electrode active material region 200A. The negative electrode tab region 200B represents a region where the negative electrode tab 240 is provided in a region excluding the negative electrode active material region 200A in the negative electrode portion 200. [ The negative electrode uncoated region 200C represents a region of the negative electrode portion 100 excluding the negative active material region 200A and the negative electrode tab region 200B. The negative electrode active material layer 220 and the negative electrode tab 240 are not provided in the negative electrode uncoated region 200C.

A separating part 300 is provided between the anode part 100 and the cathode part 200. The separator 300 may comprise a polymeric resin, for example, polypropylene or polyethylene. Although not shown, other separating portions may be further provided on the anode portion 100 and / or below the cathode portion 200.

The anode portion 100 and the cathode portion 200 are disposed to face each other with the separating portion 300 interposed therebetween. The positive electrode active material region 100A and the negative electrode active material region 200A are arranged to face each other and the positive electrode tab region 100B and the negative electrode uncoated region 200C are disposed to face each other, The tab regions 200B are arranged to face each other.

The positive electrode uncoated region 100C may have a width of 5 to 10 mm. As described above, the positive electrode uncoated region 100C has a shorter width than the conventional one, so that the amount of the positive electrode active material remaining in the positive electrode uncoated region 100C can be reduced, and the formation of the positive electrode active material islands can be suppressed. The first insulating resin layer 130 may be disposed to cover the first anode surface 110a of the cathode current collector 110 in the anode uncoated region 100C or may be disposed so as to cover the first anode surface 110a of the cathode current collector 110, The second insulating resin layer 230 on the second insulating resin layer 210a may be disposed so as to cover the region facing the anode uncoated region 100C. That is, the second insulating resin layer 230 may be provided on the portion of the negative electrode tab region 200B opposed to the portion where the first insulating resin layer 130 is not provided in the positive electrode uncoated region 100C, The first insulating resin layer 130C may be provided in the portion of the anode uncoated region 100C opposite to the portion where the second insulating resin layer 230 is not provided in the second insulating resin layer 200B. Therefore, even if a cathode active material island is formed on the first anode surface 110a of the anode uncoated region 100C, the anode active material is covered by the first insulating resin layer 130, The anode active material is covered with the insulating resin layer 230 so that the cathode active material of the cathode active material is prevented from contacting the anode current collector 210 or moving to the anode current collector 210. As a result, short circuit between the anode 100 and the cathode 200 due to the cathode active material can be prevented, and lithium contained in the cathode active material is transferred to the anode current collector 210, The formation of lithium dendrite can be prevented.

3A to 3F are views for explaining a method of manufacturing an electrode assembly for a secondary battery according to embodiments of the present invention.

Referring to FIG. 3A, a cathode active material layer 120 is formed on a cathode current collector 110. The first cathode active material layer 120a may be formed on the first anode surface 110a and the second cathode active material layer 120b may be formed on the second anode surface 110b. In this embodiment, the first and second cathode active material layers 120a and 120b are both formed. In another embodiment, however, only one of the first and second cathode active material layers 120a and 120b is formed . The cathode active material layer 120 may be formed by applying and patterning a slurry containing the cathode active material to the cathode current collector 110.

As the positive electrode current collector 110, a thin metal plate having excellent conductivity, for example, stainless steel, nickel, aluminum, titanium, or an alloy thereof may be used. The surface of the anode current collector 110 may be surface-treated with carbon, nickel, titanium, or silver. The cathode current collector 110 may be, for example, an aluminum thin plate or an aluminum alloy thin plate. The anode current collector 110 may include a first anode surface 110a and a second anode surface 110b. The first anode surface 110a and the second anode surface 110b may extend in parallel with each other.

LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , Li _x Ni _1-y Co _y O ₂ (0.9 ≦ _x ≦ 1.2, 0 <y <1), Li _x Ni _a Co _b Mn _{c O 2-y M y (} 0.9≤x≤1.2, a + b + c = 1, 0≤y≤1, M is at least one halogen atom, or _{S), LiMnO 2, Li x} Fe 1-y Me y _{P z O 4-a M a} (0.9≤x≤1.2, 0≤y≤0.5, 0≤z≤1, 0≤a≤1, Me is selected from Cr, Al, Mg, Mn, Co, and Ni At least one kind of metal element, M is at least one halogen element or S), and a mixture of at least one of them.

The slurry may further comprise a binder, a conductive material, a filler, and an additive.

After the cathode active material layer 120 is formed, the cathode current collector 110 may be cut so that the width of the anode uncoated region (see 100C in FIG. 2) is 5 to 10 mm. Since the positive electrode uncoated region is formed to have a shorter width than the conventional one, the amount of the positive electrode active material remaining in the positive electrode uncoated region can be reduced and the formation of the positive electrode active material island can be suppressed.

Referring to FIG. 3B, a first insulating resin layer 130 is formed on the cathode current collector 110 to cover the edge region of the cathode active material layer 120. The first insulating resin layer 130 may be an insulating resin tape. The first insulating resin layer 130 may be formed of, for example, a polyethylene terephthalate, a polypropylene, a polyester, a poly (phenylene sulfide), a polyimide, an acetate, a glass cloth, An insulating resin tape containing at least one selected from vinylidene and a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a fluorinated vinylidene-hexafluoropropylene copolymer, an epoxy resin, and a polyamide resin, And adhering to at least one edge region of the cathode active material layer 120 on the entire body 110. [ After the insulating resin tape is attached, its edge portion can be cut and removed.

The first insulating resin layer 130 is excellent in the insulation property, has excellent strength against the pressure, squeeze, and the impact upon dropping of the electrode when the electrode is wound, and excellent in stability against the non-aqueous electrolyte Do.

The first insulating resin layer 130 may include a material having heat resistance. For example, the heat-resistant temperature and melting point of the first insulating resin layer 130 may be 150 ° C or higher. As a result, the first insulating resin layer 130 can stably perform its function as an insulating film even at a high temperature. The heat-resistant material may have a high molecular weight and a high crystallinity, and examples thereof include polyvinylidene fluoride, a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a vinylidene fluoride-hexafluoropropylene copolymer , An epoxy resin, and a polyamide resin.

The first insulating resin layer 130 on the first anode surface 110a of the cathode current collector 110 may be formed to cover the anode uncoated region (see 100C in Fig. 2). Thus, even if a cathode active material island is formed on the first anode surface 110a of the anode uncoated region, the anode active material is covered by the first insulating resin layer 130 so that the cathode active material of the cathode active material island contacts the anode current collector 210 of the anode current collector) or to move to the anode current collector.

Referring to FIG. 3C, a positive electrode tab 140 is formed on a first positive electrode surface 110a of the positive electrode current collector 110. FIG. The positive electrode tab 140 may be formed of, for example, aluminum and may be attached to the positive electrode collector 110 using resistance welding.

Referring to FIG. 3D, referring to FIG. 3A, a negative electrode active material layer 220 is formed on a negative electrode collector 210. The first anode active material layer 220a may be formed on the first cathode surface 210a and the second anode active material layer 220b may be formed on the second cathode surface 210b. In this embodiment, both the first negative electrode active material layer 220a and the second negative electrode active material layer 220b are formed. In another embodiment, however, only one of the first and second negative electrode active material layers 220a and 220b is formed . The anode active material layer 220 may be formed by applying and patterning a slurry containing the anode active material to the anode current collector 210.

As the anode current collector 210, for example, stainless steel, nickel, copper, titanium or an alloy thereof may be used. The surface of the anode current collector 210 may be surface-treated with carbon, nickel, titanium, or silver. The anode current collector 210 may be, for example, a copper thin plate or a copper alloy thin plate. The anode current collector 210 may include a first cathode surface 210a and a second cathode surface 210b. The first cathode surface 210a and the second cathode surface 210b may extend in parallel with each other.

The negative electrode active material may include carbon and graphite materials such as natural graphite, artificial graphite, expanded graphite, carbon fiber, non-graphitizable carbon, carbon black, carbon nanotube, fullerene and activated carbon or a composite of carbon material and metal. The slurry may further comprise a binder, a conductive material, a filler, and an additive.

Referring to FIG. 3E, a negative electrode tab 240 is formed on a first negative electrode surface 210a of the negative electrode collector 210. FIG. The negative electrode tab 240 may be formed of, for example, nickel and may be attached to the negative electrode collector 210 using resistance welding.

Referring to FIG. 3F, a second insulating resin layer 230 covering the negative electrode tab 240 is formed on the negative electrode collector 210. The second insulating resin layer 230 may be an insulating resin tape. The second insulating resin layer 230 may be formed of, for example, polyethylene terephthalate, polypropylene, polyester, poly (phenylene sulfide), polyimide, acetate, glass cloth, An insulating resin tape containing at least one selected from the group consisting of vinylidene and a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a vinylidene fluoride-hexafluoropropylene copolymer, an epoxy resin, and a polyamide resin, And then adhering to cover the anode tabs 240 on the entire body 210. [ After the insulating resin tape is attached, its edge portion can be cut and removed.

The material of the second insulating resin layer 230 may be the same as or different from the material of the first insulating resin layer 130 and is not limited thereto as long as the present invention satisfies the requirements of the intended insulating resin layer. In addition, the first and second insulating resin layers 130 and 230 may have the same or different sizes. And the size thereof is not limited as long as it can achieve the object of preventing the occurrence of the cathode active material island. For example, the second insulating resin layer 230 attached to the negative electrode tab 240 may be formed longer than the first insulating resin layer 130, or may be formed shorter than the first insulating resin layer 130. That is, when one of the first insulating resin layer 130 and the second insulating resin layer 230 is long, the other one may be short.

The second insulating resin layer 230 is excellent in the insulating property, has excellent strength against the pressure, squeeze and the like which are received when the electrode is wound, strength against the impact upon dropping the battery, and excellent stability against the non-aqueous electrolyte Do.

The second insulating resin layer 230 may include a material having heat resistance. For example, the heat-resistant temperature and melting point of the second insulating resin layer 230 may be 150 ° C or higher. Thus, the second insulating resin layer 230 can stably perform its function as an insulating film even at a high temperature. The heat-resistant material may have a high molecular weight and a high crystallinity, and examples thereof include polyvinylidene fluoride, a derivative thereof such as a carboxylic acid modified product or a maleic acid modified product, a vinylidene fluoride-hexafluoropropylene copolymer , An epoxy resin, and a polyamide resin.

The second insulating resin layer 230 on the first cathode surface 210a of the anode current collector 210 may be arranged to cover the opposite region corresponding to the anode uncoated region (see 100C in Fig. 2). Thus, even if the cathode active material islands are formed on the first anode surface 110a of the anode uncoated region 100C, the opposing anode collector 210 is covered with the second insulating resin layer 230, The cathode active material of the island can be prevented from contacting the anode current collector 210 or moving to the anode current collector 210.

Referring again to FIG. 2, the anode portion 100 and the cathode portion 200 are disposed to face each other, and a separating portion 300 is provided therebetween. The separating portion 300 may be formed of a polymer resin, for example, polypropylene or polyethylene. The positive electrode active material region 100A and the negative electrode active material region 200A are arranged to face each other and the positive electrode tab region 100B and the negative electrode uncoated region 200C are disposed to face each other, The tab regions 200B are arranged to face each other.

The electrode assembly for a secondary battery according to embodiments of the present invention can be formed by winding the stacked anode part 100, separating part 300, and cathode part 200. The secondary battery electrode assembly may be a jelly roll type.

A secondary battery according to embodiments of the present invention may be formed by providing the secondary battery electrode assembly in a battery case and injecting an electrolyte into the battery case.

Hereinafter, specific embodiments of the present invention have been described. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

100: anode part 100A: cathode active material area
100B: Positive electrode tap region 100C: Positive electrode uncoated region
110: positive electrode current collector 120: positive electrode active material layer
130: first insulating resin layer 140: positive electrode tab
200: cathode part 200A: anode active material area
200B: negative electrode tab region 200C: negative electrode uncoated region
210: anode current collector 220: anode active material layer
230: second insulating resin layer 240: negative electrode tab
300:

Claims (8)

A positive electrode portion including a positive electrode active material region provided with a positive electrode active material layer, a positive electrode tab region provided with a positive electrode tab, and a positive electrode uncoated region;
A negative electrode active material region provided with a negative electrode active material layer and facing the positive electrode active material region, a negative electrode tab region provided with a negative electrode tab region facing the positive electrode uncoated region, and a negative electrode uncoated region facing the positive electrode tab region, A cathode portion; And
And a separator provided between the anode portion and the cathode portion,
The width of the positive electrode non-coated area is 5 mm to 10 mm,
Wherein the anode portion further includes an anode portion insulating resin layer extending from edges of both end portions of the cathode active material layer and covering a part of the anode uncoated region,
The negative electrode portion further includes a negative electrode portion insulating resin layer covering the negative electrode tab and covering the negative electrode collector facing the positive electrode uncoated region,
The negative electrode portion insulating resin layer is provided in the portion of the negative electrode tab region opposed to the portion where the positive electrode portion insulating resin layer is not provided in the positive electrode uncoated portion,
Wherein the positive electrode portion insulating resin layer is provided in a portion of the positive electrode uncoated region opposite to a portion of the negative electrode tap region not provided with the negative electrode portion insulating resin layer. The method according to claim 1,
Wherein the anode portion insulating resin layer and the cathode portion insulating resin insulating layer are made of a material selected from the group consisting of polyethylene terephthalate, polypropylene, polyester, polyphenylene sulfide, polyimide, acetate, glass fabric, polyvinylidene fluoride, A hexafluoropropylene copolymer, a hexafluoropropylene copolymer, an epoxy resin, and a polyamide resin. The method according to claim 1,
Wherein the positive electrode active material layer is made of LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , Li _x Ni _1-y Co _y O ₂ (0.9 ≦ _x ≦ 1.2, 0 <y <1), Li _x Ni _a Co _b Mn _c O _{2 -y} M _y (0.9? _x ? 1.2, a + b + c = 1, 0? y? 1, M is at least one halogen element or S), LiMnO ₂ , Li _x Fe _{1 -y} Me _y P _z O _{4-a M a (0.9≤x≤1.2,} 0≤y≤0.5, 0≤z≤1, 0≤a≤1, Me is at least one selected from Cr, Al, Mg, Mn, Co, and Ni And M is at least one or more halogen elements or S), and a mixture of at least one of the foregoing elements. The method according to claim 1,
Wherein the negative electrode active material layer includes at least one selected from natural graphite, artificial graphite, expanded graphite, carbon fiber, non-graphitizable carbon, carbon black, carbon nanotube, fullerene, and activated carbon. A secondary battery comprising the electrode assembly for a secondary battery according to any one of claims 1 to 4. delete delete delete

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