Electrode assembly and secondary battery including the same

Abstract

To provide an electrode assembly enabling reduction of the resistance thereof, and a secondary battery including the same.SOLUTION: An electrode assembly 100 according to the present invention comprises a positive electrode sheet 110 including a positive electrode active material portion 112 that is an area on which a positive electrode active material is stacked on a positive electrode collector 111 and a positive electrode non-coating portion 113 that is an area on which the positive electrode active material is not stacked, a positive electrode tab 150 disposed in the positive electrode non-coating portion 113, a negative electrode sheet 120 comprising a negative electrode active material portion 122 that is an area on which a negative electrode active material is stacked on a negative electrode collector 121 and a negative electrode non-coating portion 123a, 123b,123c that is an area on which the negative electrode active material is not stacked, a negative electrode tab disposed in the negative electrode non-coating portion 123a, 123b, 123c, and a separator 140 configured to insulate the positive electrode sheet 110 and the negative electrode sheet 120 from each other, wherein the positive electrode non-coating portion 113 comprises a first positive electrode non-coating portion 113a and a second positive electrode non-coating portion 113b, which are provided on two portions spaced apart from each other on the positive electrode sheet 110.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2018-0084529 filed on July 20, 2018, and Korean Patent Application No. 10-2019-0066144 filed on June 4, 2019, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an electrode assembly and a secondary battery including the same. [Background technology]

[0003] Unlike primary batteries, secondary batteries are rechargeable and have the potential to be small and have large capacity, and thus have been the subject of much research and development in recent years. As technological development and demand for mobile devices increases, the demand for secondary batteries as an energy source is rapidly increasing.

[0004] Secondary batteries are classified into coin type batteries, cylindrical type batteries, square type batteries, and pouch type batteries depending on the shape of the battery case. The electrode assembly installed inside the battery case of the secondary battery is a power generating element that can be charged and discharged and has a laminated structure of electrodes and a separator.

[0005] Electrode assemblies can be roughly classified into a jelly-roll type in which a sheet-type positive electrode and negative electrode coated with an active material are wound with a separator interposed between them, a stack type in which a number of positive electrodes and negative electrodes are stacked in sequence with a separator interposed between them, and a stack / folding type in which a stack type unit cell is wound with a long separator film. Among these, the jelly-roll type electrode assembly is widely used since it is easy to manufacture and has the advantage of having a high energy density per weight. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE DISCLOSURE One aspect of the present invention is to provide an electrode assembly capable of reducing resistance, and a secondary battery including the same.

[0007] Another aspect of the present invention is to provide an electrode assembly capable of minimizing capacity loss, and a secondary battery including the same. [Means for solving the problem]

[0008] The electrode assembly according to the first embodiment of the present invention is an electrode assembly, comprising: a positive electrode sheet including a positive electrode active material portion, which is a region formed by stacking a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion, which is a region where the positive electrode active material is not stacked; a positive electrode tab provided on the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion, which is a region formed by stacking a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion, which is a region where the negative electrode active material is not stacked; the positive electrode uncoated portion may include a first positive electrode uncoated portion and a second positive electrode uncoated portion formed in two portions spaced apart from each other on the positive electrode sheet, and the negative electrode uncoated portion may include a first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, and a second negative electrode uncoated portion and a third negative electrode uncoated portion formed on both side portions of the negative electrode sheet, and the first positive electrode uncoated portion and the first negative electrode uncoated portion may be formed at positions corresponding to each other.

[0009] The secondary battery according to the embodiment of the present invention includes an electrode assembly and a battery case that accommodates the electrode assembly. The electrode assembly includes a positive electrode current collector, a positive electrode sheet including a positive electrode active material stacked on the positive electrode current collector and a positive electrode uncoated portion that is a region where the positive electrode active material is not stacked, a positive electrode tab provided on the positive electrode uncoated portion, a negative electrode current collector, a negative electrode sheet including a negative electrode active material stacked on the negative electrode current collector and a negative electrode uncoated portion that is a region where the negative electrode active material is not stacked, and the negative electrode tab provided on the positive electrode uncoated portion. The positive electrode uncoated portion may include a first positive electrode uncoated portion and a second positive electrode uncoated portion formed in two portions of the positive electrode sheet, and the negative electrode uncoated portion may include a first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, and a second negative electrode uncoated portion and a third negative electrode uncoated portion formed on both side portions of the negative electrode sheet, and the first positive electrode uncoated portion and the first negative electrode uncoated portion may be formed at positions corresponding to each other.

[0010] In addition, an electrode assembly according to a second embodiment of the present invention is an electrode assembly, comprising: a positive plate including a positive active material part in which a positive active material is applied on a first surface of a positive current collector and a first positive uncoated part which is a region where the positive active material is not applied; a positive tab attached to the first positive uncoated part; and a negative active material part in which a negative active material is applied on a first surface of a negative current collector opposite to the first surface of the positive current collector and a first negative uncoated part which is a region where the negative active material is not applied. the first positive electrode uncoated portion is located between one end and the other end of the positive electrode plate along a longitudinal direction of the positive electrode plate, the first negative electrode uncoated portion is formed at a position overlapping the first positive electrode uncoated portion, the first negative electrode uncoated portion is formed on both sides of the negative electrode plate, respectively, and is formed between a second negative electrode uncoated portion and a third negative electrode uncoated portion to which a negative electrode tab is attached, and may further include a negative electrode tab provided on the first negative electrode uncoated portion.

[0011] Furthermore, an electrode assembly according to a third embodiment of the present invention is an electrode assembly, comprising: a positive electrode sheet including a positive electrode active material portion, which is a region formed by stacking a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion, which is a region where the positive electrode active material is not stacked; a positive electrode tab provided in the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion, which is a region formed by stacking a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion, which is a region where the negative electrode active material is not stacked; a negative electrode tab provided in the negative electrode uncoated portion; and a separator for insulating between the positive electrode sheet and the negative electrode sheet, The positive electrode uncoated portion may include a first positive electrode uncoated portion formed on the positive electrode sheet, and the negative electrode uncoated portion may include a first negative electrode uncoated portion formed on the negative electrode sheet, in which the first positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, the positive electrode tab may include a first positive electrode tab provided on the first positive electrode uncoated portion, and the negative electrode tab may include a first negative electrode tab provided on the first negative electrode uncoated portion, in which the first positive electrode tab and the first negative electrode tab may be provided so as not to overlap each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other.

[0012] And, an electrode assembly according to a fourth embodiment of the present invention is an electrode assembly including a positive plate including a positive active material part in which a positive active material is applied on a first surface of a positive current collector and a first positive uncoated part which is a region where the positive active material is not applied, a positive tab attached to the first positive uncoated part, and a negative active material part in which a negative active material is applied on a first surface of a negative current collector opposite to the first surface of the positive current collector and a first negative uncoated part which is a region where the negative active material is not applied. the first positive electrode uncoated portion is located between one end and the other end of the positive electrode plate along a longitudinal direction of the positive electrode plate, the first negative electrode uncoated portion is formed at a position overlapping the first positive electrode uncoated portion, the first negative electrode uncoated portion is formed between a second negative electrode uncoated portion and a third negative electrode uncoated portion, the second negative electrode uncoated portion and the third negative electrode uncoated portion being formed on both sides of the negative electrode plate, respectively, and having a negative electrode tab attached thereto, and the battery may further include a negative electrode tab provided on the first negative electrode uncoated portion. Effect of the Invention

[0013] According to the present invention, the number of electrode tabs can be increased to reduce resistance, and in this case, the number of negative electrode tabs can be increased so that the number of negative electrode tabs is greater than the number of positive electrode tabs, thereby minimizing resistance.

[0014] In addition, according to the present invention, the negative electrode uncoated portion where the added negative electrode tab is located and the positive electrode uncoated portion where the positive electrode tab is located are formed at corresponding positions, thereby minimizing capacity loss. At this time, the gap between the end of the positive electrode tab provided in the positive electrode uncoated portion and the end of the added negative electrode tab is spaced from each other, thereby preventing the positive electrode tab and the negative electrode tab from overlapping in the direction in which the positive electrode sheet and the negative electrode sheet face each other. As a result, uneven winding can be prevented when the positive electrode sheet and the negative electrode sheet are wound.

[0015] In addition, by placing a lithium ion deposition prevention tape on the portion of the positive electrode sheet facing the negative electrode insulating tape covering the added negative electrode tab, it is possible to prevent lithium ions from accumulating and being deposited. [Brief description of the drawings]

[0016] [Figure 1] 1 is an exploded perspective view showing a secondary battery to which an electrode assembly according to a first embodiment of the present invention is applied; [Diagram 2] FIG. 4 is a partial perspective view showing another example of the arrangement of the positive electrode tab in the electrode assembly according to the first embodiment of the present invention. [Diagram 3] 1 is a front view illustrating an electrode assembly according to a first embodiment of the present invention in an unfolded state before being wound up. [Figure 4] 1 is a plan view illustrating a stacked state of an electrode assembly according to a first embodiment of the present invention before being wound up. [Diagram 5] 1 is a plan view illustrating a state in which a positive electrode sheet and a negative electrode sheet are spread out before being wound up in an electrode assembly according to a first embodiment of the present invention. [Figure 6]FIG. 1 is a partial front view showing a main part of an electrode assembly according to a first embodiment of the present invention in a wound state. [Figure 7] FIG. 11 is a front view illustrating an electrode assembly according to a second embodiment of the present invention in an unfolded state before being wound up. [Figure 8] FIG. 11 is a front view illustrating an electrode assembly according to a third embodiment of the present invention in an unfolded state before being wound up. [Figure 9] FIG. 11 is a partial front view showing a main part of the electrode assembly according to a third embodiment of the present invention in a wound state. [Figure 10] 13 is a perspective view illustrating a state in which a positive electrode plate and a negative electrode plate are spread out before being wound up in an electrode assembly according to a fourth embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The object, particular advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the drawings. In this specification, when adding reference numbers to components in each drawing, it should be noted that the same components have the same numbers as much as possible even if they are displayed on other drawings. In addition, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. In addition, in the description of the present invention, detailed descriptions of related known technologies that unnecessarily obscure the gist of the present invention will be omitted.

[0018] FIG. 1 is an exploded perspective view showing a secondary battery to which an electrode assembly according to a first embodiment of the present invention is applied, FIG. 2 is a partial perspective view showing another example of an arrangement of a positive electrode tab in the electrode assembly according to the first embodiment of the present invention, and FIG. 3 is a front view showing the electrode assembly according to the first embodiment of the present invention in an unfolded state before being wound up.

[0019] 1 and 3, an electrode assembly 100 according to a first embodiment of the present invention includes a positive electrode sheet 110 including a positive electrode active material portion 112 and a positive electrode uncoated portion 113, a positive electrode tab 150 provided in the positive electrode uncoated portion 113, a negative electrode sheet 120 including a negative electrode active material portion 122 and a negative electrode uncoated portion 123, a negative electrode tab 160 provided in the negative electrode uncoated portion 123, and a separator 140 provided between the positive electrode sheet 110 and the negative electrode sheet 120.

[0020] FIG. 4 is a plan view showing the electrode assembly according to the first embodiment of the present invention in a stacked state before being wound, FIG. 5 is a plan view showing the positive electrode sheet 110 and the negative electrode sheet 120 in the electrode assembly according to the first embodiment of the present invention in a spread state before being wound, and FIG. 6 is a partial front view showing the main parts of the electrode assembly according to the first embodiment of the present invention in a wound state.

[0021] Hereinafter, the electrode assembly according to the first embodiment of the present invention will be described in more detail with reference to FIGS.

[0022] 1 and 3, the electrode assembly 100 is a power generating element capable of charging and discharging, and has a structure in which electrodes 130 and separators 140 are assembled and alternately stacked. Here, the electrode assembly 100 is an electrode assembly 100 for a lithium ion secondary battery, and may have a wound shape.

[0023] The electrode 130 may include a positive electrode sheet 110 and a negative electrode sheet 120. The separator 140 may separate the positive electrode sheet 110 and the negative electrode sheet 120 to electrically insulate them from each other.

[0024] The positive electrode sheet 110 and the negative electrode sheet 120 may be alternately stacked and wound up like the separator 140, but may be formed in a roll shape. Here, the electrode assembly 100 may be wound up in a circular or elliptical shape, for example, to form a jelly roll shape.

[0025] 3 to 5, the positive electrode sheet 110 may include a positive electrode active material portion 112 which is a region where a positive electrode active material is laminated on a positive electrode current collector 111, and a positive electrode non-coating portion 113 which is a region where no positive electrode active material is laminated. In this case, the positive electrode sheet 110 may be, for example, in the form of a sheet.

[0026] The positive electrode current collector 111 may be made of, for example, aluminum (Al) foil.

[0027] The positive electrode active material part 112 may be formed including a positive electrode active material laminated on at least one surface of either one surface 110c or the other surface 110d of the positive electrode sheet 110. In this case, the positive electrode active material part 112 may be formed on both surfaces of the positive electrode sheet 120, for example. The positive electrode active material part 112 may be formed to further include a binder and a conductive material in addition to the positive electrode active material.

[0028] The positive electrode active material may be, for example, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a compound or mixture containing at least one of these.

[0029] As another example, the positive electrode active material may be a HiNi-based positive electrode material, which may include at least one of a LiNiMnCoO-based material, a LiNiCoAl-based material, and a LiMiMnCoAl-based material.

[0030] The binder may be, for example, any one of polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, or fluororubber.

[0031] The conductive material may be any one of the following conductive materials: graphite; carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fibers and metal fibers; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and polyphenylene derivatives.

[0032] The positive electrode uncoated portion 113 may be formed in two parts spaced apart from each other and may include a first positive electrode uncoated portion 113a and a second positive electrode uncoated portion 113b. Here, the positive electrode uncoated portion 113 may be formed on at least one of both surfaces of the positive electrode sheet 110.

[0033] The first positive electrode uncoated portion 113a and the second positive electrode uncoated portion 113b may be located between both sides of the positive electrode sheet 110 in the longitudinal direction.

[0034] Here, the first positive electrode uncoated portion 113a may be located near one side portion 110a of the positive electrode sheet 110, and the second positive electrode uncoated portion 113b may be located near the other side portion 110b of the positive electrode sheet 110, for example.

[0035] In addition, the first positive electrode uncoated region 113a may be located on the winding outer edge side when the positive electrode sheet 110 is wound, and the second positive electrode uncoated region 113b may be located on the winding center side. However, the present invention is not necessarily limited thereto, and for example, the first positive electrode uncoated region 113a may be located on the winding center side when the positive electrode sheet 110 is wound, and the second positive electrode uncoated region 113b may be located on the winding outer edge side.

[0036] The positive electrode tab 150 is provided on the positive electrode uncoated portion 113 of the positive electrode sheet 110. Here, one end of the positive electrode tab 150 may be attached and fixed to the positive electrode uncoated portion 113, and the other end may protrude from the positive electrode sheet 110.

[0037] In addition, the positive electrode tab 150 may include a first positive electrode tab 151 provided in the first positive electrode uncoated portion 113a, and a second positive electrode tab 152 provided in the second positive electrode uncoated portion 113b. Here, the first positive electrode tab 151 and the second positive electrode tab 152 are shown to be positioned on the other surface 110d of the positive electrode sheet 110 in FIG. 3 as an example, but the present invention is not necessarily limited thereto, and the first positive electrode tab 151 and the second positive electrode tab 152 may be formed on one surface 110c or the other surface 110d of the positive electrode sheet 110, respectively. In this case, as another example, the first positive electrode tab 151 and the second positive electrode tab 152 may be positioned on one surface 110c of the positive electrode sheet 110.

[0038] Meanwhile, referring to FIG. 1, the first positive electrode tab 151 and the second positive electrode tab 152 may be located on both sides of the winding central axis C of the wound electrode assembly 100, for example.

[0039] 2, in the positive electrode tab 150, the first positive electrode tab 151' and the second positive electrode tab 152 may be located on one side of the winding central axis C in the wound electrode assembly 100'. That is, the first positive electrode tab 151' and the second positive electrode tab 152 may be sequentially arranged in a direction from the winding central axis C toward the outer circumferential surface of the electrode assembly 100'. In this case, the first positive electrode tab 151' and the second positive electrode tab 152 may be arranged on a line extending in a direction perpendicular to the winding central axis C.

[0040] 3 to 5, the negative electrode sheet 120 may include a negative electrode active material portion 122 which is a region where a negative electrode active material is laminated on a negative electrode current collector 121, and a negative electrode uncoated portion 123 which is a region where no negative electrode active material is laminated. In this case, the negative electrode sheet 120 may be in the form of, for example, a sheet.

[0041] The negative electrode current collector 121 may be, for example, a foil made of copper (Cu) or nickel (Ni).

[0042] The negative electrode active material part 122 may be formed including a negative electrode active material laminated on at least one surface of the first surface 120c or the second surface 120d of the negative electrode sheet 120. In this case, the negative electrode active material part 122 may be formed on both surfaces of the negative electrode sheet 120, for example. The negative electrode active material part 122 may be formed to further include a binder and a conductive material in addition to the negative electrode active material.

[0043] The negative electrode active material may be, for example, a material containing artificial graphite.

[0044] In addition, the negative electrode active material may be, for example, lithium metal, a lithium alloy, carbon, petroleum coke, activated carbon, graphite, a silicon compound, a tin compound, a titanium compound, or an alloy thereof.

[0045] The negative electrode uncoated portion 123 may include a first negative electrode uncoated portion 123a formed between both sides in the longitudinal direction of the negative electrode sheet 120, and a second negative electrode uncoated portion 123b and a third negative electrode uncoated portion 123c formed on both sides of the negative electrode sheet 120. Here, the negative electrode uncoated portion 123 may be formed on at least one of both sides of the negative electrode sheet 120.

[0046] Meanwhile, referring to FIGS. 3, 5 and 6, the first positive electrode uncoated portion 113a and the first negative electrode uncoated portion 123a may be formed at positions corresponding to each other.

[0047] 3 to 5, the negative electrode tab 160 is provided on the negative electrode uncoated portion 123. Here, one end of the negative electrode tab 160 may be attached and fixed to the negative electrode uncoated portion 123, and the other end may protrude from the negative electrode sheet 120.

[0048] In addition, the negative electrode tab 160 may include a first negative electrode tab 161 provided in the first negative electrode uncoated portion 123a, a second negative electrode tab 162 provided in the second negative electrode uncoated portion 123b, and a third negative electrode tab 163 provided in the third negative electrode uncoated portion 123c. Here, the first negative electrode tab 161 and the second negative electrode tab 162 are shown to be positioned on one surface 120c and the other surface 120d of the negative electrode sheet 120 in FIG. 3 as an example, but the present invention is not necessarily limited thereto, and the first negative electrode tab 161, the second negative electrode tab 162, and the third negative electrode tab 163 may be formed on the one surface 120c or the other surface 120d of the negative electrode sheet 120, respectively. In this case, as another example, the first negative electrode tab 161 and the second negative electrode tab 162 may be positioned on the other surface 120d of the negative electrode sheet 120, and the third negative electrode tab 163 may be positioned on one surface 120c of the negative electrode sheet 120.

[0049] 1, 3 and 6, the separator 140 is made of an insulating material and is alternately laminated with the positive electrode sheet 110 and the negative electrode sheet 120. Here, the separator 140 may be located between the positive electrode sheet 110 and the negative electrode sheet 120 and on the outer surfaces of the positive electrode sheet 110 and the negative electrode sheet 120.

[0050] In addition, the separator 140 may be formed of a material having uniform micropores. Specifically, the separator 140 may be a multi-layer film made of microporous polyethylene, polypropylene, or a combination thereof, or a polymer film for a solid polymer electrolyte or a gel-type polymer electrolyte, such as polyvinylidene fluoride, polyethylene oxide, polyacrylonitrile, or polyvinylidene fluoride-hexafluoropropylene copolymer.

[0051] The separator 140 may include a first separator 141 positioned between one surface 110c of the positive electrode sheet 110 and the other surface 120d of the negative electrode sheet 120, and a second separator 142 positioned on one surface 120c of the negative electrode sheet 120.

[0052] 1, 4 and 5, the first positive electrode tab 151 and the first negative electrode tab 161 may be provided so as not to overlap with each other in a direction in which the positive electrode sheet 110 and the negative electrode sheet 120 face each other. Here, the direction in which the positive electrode sheet 110 and the negative electrode sheet 120 face each other may be, for example, a side direction S of the winding central axis C.

[0053] In addition, the first positive electrode tab 151 may protrude in one direction C1 based on a direction parallel to a winding central axis C, which is a central axis about which the electrode assembly 100 is wound, and the first negative electrode tab 161 may protrude in the other direction C2 based on a direction parallel to the winding central axis C. Here, referring to FIG. 1 , for example, the first positive electrode tab 151 may protrude in an upward direction of the electrode assembly 100 and be connected to the cap assembly 12, and the first negative electrode tab 161 may protrude in a downward direction of the electrode assembly 100 and be connected to an inner bottom surface of the battery case 11.

[0054] Ends of the first positive electrode tab 151 and the first negative electrode tab 161 may be spaced apart from each other by a predetermined distance in a direction parallel to the winding central axis C so as not to overlap with each other.

[0055] 1, 3, and 6, one surface 110c, 120c of each of the positive electrode sheet 110 and the negative electrode sheet 120 may be positioned toward the inside direction S1 when wound, and the other surface 110d, 120d may be positioned toward the outside direction S2 of the winding side. In this case, the first positive electrode tab 151 may be positioned on the other surface 110d of the positive electrode sheet 110, and the first negative electrode tab 161 may be positioned on one surface 120c of the negative electrode sheet 120.

[0056] For example, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound such that one side 110a, 120a is wound and positioned at the outer winding portion, and the other side 110b, 120b is positioned at the winding center portion. In this case, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound around the other side 110b, 120b. Here, the winding center portion may be a central region after the positive electrode sheet 110 and the negative electrode sheet 120 are wound, and the winding outer portion may be an outer region after the positive electrode sheet 110 and the negative electrode sheet 120 are wound. In this case, referring to the details shown in FIG. 3, the winding direction R of the positive electrode sheet 110 and the negative electrode sheet 120 may be, for example, a clockwise direction. That is, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound such that one side portion 110a, 120a is wound clockwise around the other side portion 110b, 120b.

[0057] However, the present invention is not necessarily limited thereto. As another example, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound such that one side 110a, 120a is wound and positioned at the winding center, and the other side 110b, 120b is positioned at the winding outer periphery. In this case, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound around one side 110a, 120a. That is, the winding is opposite to that in the example. In this case, the winding direction R' of the positive electrode sheet 110 and the negative electrode sheet 120 may be, for example, counterclockwise.

[0058] The first and second positive electrode uncoated regions 113a, 113b are formed between both sides of the positive electrode sheet 110, and the first positive electrode uncoated region 113a may be located on one side 110a of the positive electrode sheet 110.

[0059] 3 and 4, in the electrode assembly 100 according to the first embodiment of the present invention, a positive electrode insulating tape 170 may be further attached to the positive electrode uncoated portion 113 to cover the positive electrode tab 150, and a negative electrode insulating tape 180 may be further attached to the negative electrode uncoated portion 123 to cover the negative electrode tab 160. Here, the positive electrode insulating tape 170 and the negative electrode insulating tape 180 made of an insulating material are provided to cover the positive electrode tab 150 and the negative electrode tab 160, so that the separator 140 can be prevented from being ruptured due to the corners of the positive electrode tab 150 and the negative electrode tab 160, and the separator 140 can be prevented from being in direct contact with the negative electrode sheet 120 or the negative electrode tab 160 from being in direct contact with the positive electrode sheet 110 through the damaged portion when the separator 140 is damaged, thereby preventing a short circuit from occurring.

[0060] The positive electrode insulating tape 170 may include a first positive electrode insulating tape 171 attached to the first positive electrode uncoated portion 113a to cover the first positive electrode tab 151, and a second positive electrode insulating tape 172 attached to the second positive electrode uncoated portion 113b to cover the second positive electrode tab 152.

[0061] The negative electrode insulating tape 180 may include a first negative electrode insulating tape 181 attached to the first negative electrode uncoated portion 123a to cover the first negative electrode tab 161, a second negative electrode insulating tape 182 attached to the second negative electrode uncoated portion 123b to cover the second negative electrode tab 162, and a third negative electrode insulating tape 183 attached to the third negative electrode uncoated portion 123c to cover the third negative electrode tab 163. In addition, the negative electrode insulating tape 180 may further include a fourth negative electrode insulating tape 184 attached to a surface of the second negative electrode uncoated portion 123b opposite to the surface where the second negative electrode tab 162 is located. That is, the second negative electrode uncoated portion 123b may be formed on both sides of the negative electrode sheet 120, and in this case, the second negative electrode tab 162 may be positioned on one side of the second negative electrode uncoated portion 123b, and the fourth negative electrode insulating tape 184 may be positioned on the other side of the second negative electrode uncoated portion 123b.

[0062] The positive electrode insulating tape 170 and the negative electrode insulating tape 180 may be formed to include an electrically insulating material. In this case, the positive electrode insulating tape 170 and the negative electrode insulating tape 180 may not have pores through which lithium ions can move. As a result, the positive electrode insulating tape 170 and the negative electrode insulating tape 180 are made of a material that is resistant to physical damage, and therefore are not damaged by corners of the positive electrode tab 150 and the negative electrode tab 160, and damage to the portion of the separator 140 facing the positive electrode tab 150 and the negative electrode tab 160 can also be prevented.

[0063] Meanwhile, the positive electrode insulating tape 170 and the negative electrode insulating tape 180 may include, for example, a substrate (not shown) and an adhesive layer (not shown) formed on one surface of the substrate.

[0064] Meanwhile, referring to Fig. 3 and Fig. 6, in the electrode assembly 100 according to the first embodiment of the present invention, a lithium ion deposition prevention tape 190 may be further attached to a portion of the positive electrode sheet 110 facing the first negative electrode insulating tape 181 with the separator 140 interposed therebetween. Here, the lithium ion deposition prevention tape 190 may be provided on, for example, the other surface 110d of the positive electrode sheet 110, and may be positioned on a surface of the positive electrode active material part 112 laminated between one side 110a of the positive electrode sheet 110 and the first positive electrode uncoated part 113a located near the one side 110a of the positive electrode sheet 110. In this case, the lithium ion deposition prevention tape 190 and the first negative electrode uncoated part 123a may face each other with the second separator 142 interposed therebetween. The lithium ion deposition prevention tape 190 may be formed including an electrically insulating material.

[0065] As a result, the lithium ion deposition prevention tape 190 is positioned in the portion of the positive electrode sheet 110 facing the first negative electrode uncoated portion 123a to which the first negative electrode insulating tape 181 is attached during charging and discharging, and lithium ions are not exchanged, thereby preventing the accumulation and deposition of lithium ions.

[0066] That is, by attaching the lithium ion precipitation prevention tape 190 to the surface of the positive electrode active material part 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181, lithium ions are exchanged between the positive electrode sheet 110 and the negative electrode sheet 120, and it is possible to prevent lithium ions from accumulating and being precipitated in the parts where the lithium ions are not exchanged by the first negative electrode insulating tape 181 during charging and discharging.

[0067] More specifically, the separator 140 is disposed between the positive electrode sheet 110 and the negative electrode sheet 120 in a thin film shape to prevent direct contact between the positive electrode sheet 110 and the negative electrode sheet 120, and lithium ions are transferred through micropores of the separator 140 to charge and discharge the battery. Here, the first negative electrode insulating tape 181 is made of an insulating material without micropores, so that the lithium ions are not transferred. At this time, the lithium ions that are blocked by the first negative electrode insulating tape 181 and cannot be transferred may accumulate and precipitate on the surface of the positive electrode active material part 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181. Therefore, in the electrode assembly 100 according to the first embodiment of the present invention, a lithium ion deposition prevention tape 190 made of an insulating material is attached to the surface of the positive electrode active material part 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181, thereby preventing lithium ions from accumulating on the surface of the positive electrode active material part 112 facing the first negative electrode insulating tape 181.

[0068] Meanwhile, the lithium ion deposition prevention tape 190 may be formed containing, for example, PI (polyimide).

[0069] Also, the lithium ion deposition prevention tape 190 may include, for example, a substrate (not shown) and an adhesive layer (not shown) formed on one surface of the substrate.

[0070] Referring to FIG. 3, the electrode assembly 100 according to the first embodiment of the present invention configured as described above can reduce resistance by adding a first negative electrode tab 161 such that the number of negative electrode tabs 160 is greater than the number of positive electrode tabs 150.

[0071] At this time, the first negative electrode uncoated portion 123a is additionally formed to attach the first negative electrode tab 161, and the first negative electrode uncoated portion 123a is formed to correspond to the first positive electrode uncoated portion 113a where the first positive electrode tab 151 is located, thereby preventing or significantly reducing additional loss of battery capacity. That is, if an additional positive electrode uncoated portion is formed on the positive electrode sheet 110 corresponding to the additional formation of the first negative electrode uncoated portion 123a, the positive electrode active material portion 122 is reduced and the battery capacity is reduced. Therefore, by aligning the first negative electrode uncoated portion 123a with the first positive electrode uncoated portion 113a where the first positive electrode tab 151 is located to prevent the formation of an additional positive electrode uncoated portion, the reduction in battery capacity can be significantly reduced or prevented.

[0072] Hereinafter, an electrode assembly according to a second embodiment of the present invention will be described.

[0073] FIG. 7 is a front view showing an electrode assembly according to a second embodiment of the present invention in an unfolded state before being wound up.

[0074] 7, the electrode assembly 200 according to the second embodiment of the present invention includes a positive electrode sheet 210 including a positive electrode active material portion 212 and a positive electrode uncoated portion 213, a positive electrode tab 250 provided on the positive electrode uncoated portion 213, a negative electrode sheet 220 including a negative electrode active material portion 222 and a negative electrode uncoated portion 223, a negative electrode tab 260 provided on the negative electrode uncoated portion 223, and a separator 140 provided between the positive electrode sheet 210 and the negative electrode sheet 220.

[0075] The electrode assembly 200 according to the second embodiment of the present invention differs from the electrode assembly 100 according to the first embodiment in the positions of the positive electrode uncoated portion 213 and the negative electrode uncoated portion 223. In this embodiment, the contents that overlap with the above-mentioned embodiment will be briefly described, and the differences will be mainly described.

[0076] More specifically, the positive electrode sheet 210 may include a positive electrode active material portion 212 which is a region where a positive electrode active material is laminated on a positive electrode current collector 211, and a positive electrode uncoated portion 213 which is a region where no positive electrode active material is laminated.

[0077] The positive electrode uncoated portion 213 may be formed in two parts spaced apart from each other, and may include a first positive electrode uncoated portion 213a and a second positive electrode uncoated portion 213b. Here, the positive electrode uncoated portion 213 may be formed on at least one of both surfaces of the positive electrode sheet 210.

[0078] The first positive electrode uncoated portion 213a and the second positive electrode uncoated portion 213b may be located between both sides of the positive electrode sheet 210 in the longitudinal direction.

[0079] Here, the first positive electrode uncoated portion 213a may be located near the other side portion 210b of the positive electrode sheet 210, and the second positive electrode uncoated portion 213b may be located near the one side portion 210a of the positive electrode sheet 210, for example.

[0080] In addition, the first positive electrode uncoated region 213a may be located on the winding outer edge side when the positive electrode sheet 210 is wound, and the second positive electrode uncoated region 213b may be located on the winding center side. However, the present invention is not necessarily limited thereto, and for example, the first positive electrode uncoated region 213a may be located on the winding center side when the positive electrode sheet 210 is wound, and the second positive electrode uncoated region 213b may be located on the winding outer edge side.

[0081] The positive electrode tab 250 is provided on the positive electrode uncoated portion 213 of the positive electrode sheet 210. Here, one end of the positive electrode tab 250 may be attached and fixed to the positive electrode uncoated portion 213, and the other end may protrude from the positive electrode sheet 210.

[0082] In addition, the positive electrode tab 250 may include a first positive electrode tab 251 provided in the first positive electrode uncoated portion 213a, and a second positive electrode tab 252 provided in the second positive electrode uncoated portion 213b.

[0083] The negative electrode sheet 220 may include a negative electrode active material portion 222 which is a region where a negative electrode active material is laminated on a negative electrode current collector 221, and a negative electrode uncoated portion 223 which is a region where no negative electrode active material is laminated.

[0084] The negative electrode uncoated portion 223 may include a first negative electrode uncoated portion 223a formed between both sides in the longitudinal direction of the negative electrode sheet 220, and a second negative electrode uncoated portion 223b and a third negative electrode uncoated portion 223c formed on both sides of the negative electrode sheet 220. Here, the negative electrode uncoated portion 223 may be formed on at least one of both sides of the negative electrode sheet 220.

[0085] Meanwhile, the second positive electrode uncoated portion 213b and the first negative electrode uncoated portion 223a may be formed at positions corresponding to each other.

[0086] The negative electrode tab 260 may be provided on the negative electrode uncoated portion 223. Here, one end of the negative electrode tab 260 may be attached and fixed to the negative electrode uncoated portion 223, and the other end may protrude from the negative electrode sheet 220.

[0087] In addition, the negative electrode tab 260 may include a first negative electrode tab 261 provided in the first negative electrode uncoated portion 223a, a second negative electrode tab 262 provided in the second negative electrode uncoated portion 223b, and a third negative electrode tab 263 provided in the third negative electrode uncoated portion 223c.

[0088] In the electrode assembly 200 according to the second embodiment of the present invention, a positive electrode insulating tape 270 may be further attached to the positive electrode uncoated portion 213 to cover the positive electrode tab 250, and a negative electrode insulating tape 280 may be further attached to the negative electrode uncoated portion 223 to cover the negative electrode tab 260.

[0089] The positive electrode insulating tape 270 may include a first positive electrode insulating tape 271 attached to the first positive electrode uncoated portion 213a to cover the first positive electrode tab 251, and a second positive electrode insulating tape 272 attached to the second positive electrode uncoated portion 213b to cover the second positive electrode tab 252.

[0090] The negative electrode insulating tape 280 may include a first negative electrode insulating tape 281 attached to the first negative electrode uncoated portion 223a to cover the first negative electrode tab 261, a second negative electrode insulating tape 282 attached to the second negative electrode uncoated portion 223b to cover the second negative electrode tab 262, and a third negative electrode insulating tape 283 attached to the third negative electrode uncoated portion 223c to cover the third negative electrode tab 263. In addition, the negative electrode insulating tape 280 may further include a fourth negative electrode insulating tape 284 attached to a surface of the second negative electrode uncoated portion 123b opposite to the surface where the second negative electrode tab 162 is located. That is, the second negative electrode uncoated portion 223b may be formed on both sides of the negative electrode sheet 220, and in this case, the second negative electrode tab 262 may be positioned on one side of the second negative electrode uncoated portion 223b, and the fourth negative electrode insulating tape 284 may be positioned on the other side of the second negative electrode uncoated portion 223b.

[0091] Hereinafter, an electrode assembly according to a third embodiment of the present invention will be described with reference to FIGS.

[0092] FIG. 8 is a front view showing an electrode assembly according to a third embodiment of the present invention in an unfolded state before being wound up, and FIG. 9 is a partial front view showing a main part of the electrode assembly according to the third embodiment of the present invention in a wound up state.

[0093] 8 and 9, an electrode assembly 300 according to the third embodiment of the present invention includes a positive electrode sheet 310 including a positive electrode active material portion 312 and a positive electrode uncoated portion 313, a positive electrode tab 350 provided in the positive electrode uncoated portion 313, a negative electrode sheet 320 including a negative electrode active material portion 322 and a negative electrode uncoated portion 323, a negative electrode tab 360 provided in the negative electrode uncoated portion 323, and a separator 140 provided between the positive electrode sheet 310 and the negative electrode sheet 320.

[0094] The electrode assembly 300 according to the third embodiment of the present invention has a different winding form when compared with the electrode assembly according to the first embodiment and the electrode assembly according to the second embodiment. In this embodiment, the contents overlapping with the above-mentioned embodiments will be omitted or briefly described, and the description will focus on the differences.

[0095] More specifically, the positive electrode sheet 310 may include a positive electrode active material portion 312 which is a region where a positive electrode active material is laminated on a positive electrode current collector 311, and a positive electrode uncoated portion 313 which is a region where no positive electrode active material is laminated.

[0096] The positive electrode uncoated portion 313 may be formed in two parts spaced apart from each other, and may include a first positive electrode uncoated portion 313a and a second positive electrode uncoated portion 313b. Here, the positive electrode uncoated portion 313 may be formed on at least one of both surfaces of the positive electrode sheet 310.

[0097] The first positive electrode uncoated portion 313a and the second positive electrode uncoated portion 313b may be located between both sides of the positive electrode sheet 310 in the longitudinal direction.

[0098] Here, the first positive electrode uncoated portion 313a may be located near one side portion 310a of the positive electrode sheet 310, and the second positive electrode uncoated portion 313b may be located near the other side portion 310b of the positive electrode sheet 310, for example.

[0099] In addition, the first positive electrode uncoated region 313a may be located toward the winding center when the positive electrode sheet 310 is wound, and the second positive electrode uncoated region 313b may be located toward the winding outer periphery. However, the present invention is not necessarily limited thereto, and for example, the first positive electrode uncoated region 313a may be located toward the winding outer periphery when the positive electrode sheet 310 is wound, and the second positive electrode uncoated region 313b may be located toward the winding center.

[0100] The positive electrode tab 350 is provided on the positive electrode uncoated portion 313 of the positive electrode sheet 310. Here, one end of the positive electrode tab 350 may be attached and fixed to the positive electrode uncoated portion 313, and the other end may protrude from the positive electrode sheet 310.

[0101] In addition, the positive electrode tab 350 may include a first positive electrode tab 351 provided in the first positive electrode uncoated portion 313a and a second positive electrode tab 352 provided in the second positive electrode uncoated portion 313b. Here, the first positive electrode tab 351 and the second positive electrode tab 352 may be located on the other surface 310d of the positive electrode sheet 310, for example.

[0102] 9, the first positive electrode tab 351 and the second positive electrode tab 352 are shown to be located on the other surface 310d of the positive electrode sheet 310, but the present invention is not necessarily limited thereto, and the first positive electrode tab 351 and the second positive electrode tab 352 may be formed on one surface 310c or the other surface 310d of the positive electrode sheet 310, respectively. In this case, as another example, the first positive electrode tab 351 and the second positive electrode tab 352 may be located on one surface 310c of the positive electrode sheet 310.

[0103] The negative electrode sheet 320 may include a negative electrode active material portion 322 which is a region where a negative electrode active material is laminated on a negative electrode current collector 321, and a negative electrode uncoated portion 323 which is a region where no negative electrode active material is laminated.

[0104] The negative electrode uncoated portion 323 may include a first negative electrode uncoated portion 323a formed between both sides in the longitudinal direction of the negative electrode sheet 320, and a second negative electrode uncoated portion 323b and a third negative electrode uncoated portion 323c formed on both sides of the negative electrode sheet 320. Here, the negative electrode uncoated portion 323 may be formed on at least one of both sides of the negative electrode sheet 320.

[0105] Meanwhile, the first positive electrode uncoated portion 313a and the first negative electrode uncoated portion 323a may be formed at positions corresponding to each other.

[0106] The negative electrode tab 360 may be provided on the negative electrode uncoated portion 323. Here, one end of the negative electrode tab 360 may be attached and fixed to the negative electrode uncoated portion 323, and the other end may protrude from the negative electrode sheet 320.

[0107] In addition, the negative electrode tab 360 may include a first negative electrode tab 361 provided in the first negative electrode uncoated portion 323a, a second negative electrode tab 362 provided in the second negative electrode uncoated portion 323b, and a third negative electrode tab 363 provided in the third negative electrode uncoated portion 323c. Here, the first negative electrode tab 361 and the second negative electrode tab 362 are shown to be positioned on one surface 320c of the negative electrode sheet 320, and the third negative electrode tab 363 is shown to be positioned on the other surface 320d of the negative electrode sheet 320 in FIG. 8, for example, but the present invention is not necessarily limited thereto, and the first negative electrode tab 361, the second negative electrode tab 362, and the third negative electrode tab 363 may be formed on the one surface 320c or the other surface 320d of the negative electrode sheet 320, respectively. In this case, as another example, the first negative electrode tab 361 and the second negative electrode tab 362 may be positioned on the other surface 320d of the negative electrode sheet 320, and the third negative electrode tab 363 may be positioned on one surface 320c of the negative electrode sheet 320.

[0108] Meanwhile, one side 310c, 320c of each of the positive electrode sheet 310 and the negative electrode sheet 320 may be positioned toward the outside when wound, and the other side 310d, 320d may be positioned toward the inside of the winding side. In this case, the first positive electrode tab 351 may be positioned on the other side 310d of the positive electrode sheet 310, and the first negative electrode tab 361 may be positioned on one side 320c of the negative electrode sheet 320.

[0109] For example, the positive electrode sheet 310 and the negative electrode sheet 320 may be wound such that the other side portions 310b, 320b are wound on both sides and positioned at the winding center, and the one side portions 310a, 320a are wound and positioned at the winding outer periphery. In this case, the positive electrode sheet 310 and the negative electrode sheet 320 may be wound starting from the other side portions 310b, 320b and wound toward the one side portions 310a, 320a, but in a clockwise direction. In this case, the winding direction R of the positive electrode sheet 310 and the negative electrode sheet 320 may be, for example, a clockwise direction.

[0110] However, the present invention is not necessarily limited thereto. As another example, the positive electrode sheet 310 and the negative electrode sheet 320 may be wound such that the other side portions 310b, 320b are wound at both sides and positioned at the winding center, and the one side portion 310a, 320a is positioned at the winding outer periphery. In this case, the positive electrode sheet 310 and the negative electrode sheet 320 may be wound around the other side portions 310b, 320b. That is, the winding is performed in the opposite direction to the example. In this case, the winding direction R' of the positive electrode sheet 310 and the negative electrode sheet 320 may be, for example, counterclockwise.

[0111] In the electrode assembly 300 according to the third embodiment of the present invention, a positive electrode insulating tape 370 may be further attached to the positive electrode uncoated portion 313 to cover the positive electrode tab 350, and a negative electrode insulating tape 380 may be further attached to the negative electrode uncoated portion 323 to cover the negative electrode tab 360.

[0112] The positive electrode insulating tape 370 may include a first positive electrode insulating tape 371 attached to the first positive electrode uncoated portion 313a to cover the first positive electrode tab 351, and a second positive electrode insulating tape 372 attached to the second positive electrode uncoated portion 313b to cover the second positive electrode tab 352.

[0113] The negative electrode insulating tape 380 may include a first negative electrode insulating tape 381 attached to the first negative electrode uncoated portion 323a to cover the first negative electrode tab 361, a second negative electrode insulating tape 382 attached to the second negative electrode uncoated portion 323b to cover the second negative electrode tab 362, and a third negative electrode insulating tape 383 attached to the third negative electrode uncoated portion 323c to cover the third negative electrode tab 363. In addition, the negative electrode insulating tape 380 may further include a fourth negative electrode insulating tape 384 attached to a surface of the second negative electrode uncoated portion 323b opposite to the surface where the second negative electrode tab 362 is located. That is, the second negative electrode uncoated portion 323b may be formed on both sides of the negative electrode sheet 320, and in this case, the second negative electrode tab 362 may be positioned on one side of the second negative electrode uncoated portion 323b, and the fourth negative electrode insulating tape 384 may be positioned on the other side of the second negative electrode uncoated portion 323b.

[0114] Meanwhile, in the electrode assembly 300 according to the third embodiment of the present invention, a lithium ion deposition prevention tape 390 may be further attached to a portion of the positive electrode sheet 310 facing the first negative electrode insulating tape 381 with the separator 140 interposed therebetween.

[0115] Hereinafter, a secondary battery including an electrode assembly according to an embodiment of the present invention will be described with reference to FIGS.

[0116] 1 and 2, a secondary battery 10 according to an embodiment of the present invention includes an electrode assembly 100 and a battery case 11 that accommodates the electrode assembly 100. Here, the electrode assembly 100 includes a positive electrode sheet 110 including a positive electrode active material portion 112 and a positive electrode uncoated portion 113, a positive electrode tab 150 provided in the positive electrode uncoated portion 113, a negative electrode sheet 120 including a negative electrode active material portion 122 and a negative electrode uncoated portion 123, a negative electrode tab 160 provided in the negative electrode uncoated portion 123, and a separator 140 provided between the positive electrode sheet 110 and the negative electrode sheet 120.

[0117] The secondary battery 10 according to the embodiment of the present invention is a secondary battery 10 including an electrode assembly according to the first embodiment to the third embodiment, and the contents of this embodiment that overlap with the above-mentioned embodiments will be briefly described, and the differences will be mainly described.

[0118] 1, in a secondary battery 10 according to an embodiment of the present invention, a battery case 11 may be formed with a receiving portion 11a that receives an electrolyte and an electrode assembly 100 therein. In this case, the battery case 11 may be opened such that the receiving portion 11a is open on one side, and a cap assembly 12 may be further provided to cover the open side of the battery case 11. Here, the battery case 11 may have, for example, an elliptical or cylindrical shape.

[0119] In addition, the electrode assembly 100 is a power generating element capable of charging and discharging, and has a structure in which electrodes 130 and separators 140 are assembled and alternately stacked. Here, the electrode assembly 100 is an electrode assembly 100 for a lithium ion secondary battery, and may have a wound form.

[0120] The electrode 130 may include a positive electrode sheet 110 and a negative electrode sheet 120. The separator 140 may separate the positive electrode sheet 110 and the negative electrode sheet 120 to electrically insulate them from each other.

[0121] 1 to 4, the positive electrode sheet 110 may include a positive electrode active material portion 112 which is a region formed by stacking a positive electrode active material on a positive electrode current collector 111, and a positive electrode uncoated portion 113 which is a region where the positive electrode active material is not stacked. Here, the positive electrode uncoated portion 113 is formed in two portions spaced apart from each other in the positive electrode sheet 110, and may include a first positive electrode uncoated portion 113a and a second positive electrode uncoated portion 113b.

[0122] The positive electrode tab 150 is provided in the positive electrode uncoated portion 113 of the positive electrode sheet 110. Here, one end of the positive electrode tab 150 may be attached and fixed to the positive electrode uncoated portion 113, and the other end may protrude from the positive electrode sheet 110. In this case, the positive electrode tab 150 may protrude toward the bottom surface of the cap assembly 12 or the battery case 11.

[0123] In addition, the positive electrode tab 150 may include a first positive electrode tab 151 provided in the first positive electrode uncoated portion 113a, and a second positive electrode tab 152 provided in the second positive electrode uncoated portion 113b.

[0124] The negative electrode sheet 120 may include a negative electrode active material portion 122 which is a region formed by stacking a negative electrode active material on a negative electrode current collector 121, and a negative electrode uncoated portion 123 which is a region where the negative electrode active material is not stacked. Here, the negative electrode uncoated portion 123 may include a first negative electrode uncoated portion 123a formed between both side portions of the negative electrode sheet 120, and a second negative electrode uncoated portion 123b and a third negative electrode uncoated portion 123c formed on both side portions of the negative electrode sheet 120. Here, the first negative electrode uncoated portion 123a may be formed on one side portion 120a of the negative electrode sheet 120, and the second negative electrode uncoated portion 123b may be formed on the other side portion 120b of the negative electrode sheet 120.

[0125] The negative electrode tab 160 is provided in the negative electrode uncoated portion 123. Here, one end of the negative electrode tab 160 may be attached and fixed to the negative electrode uncoated portion 123, and the other end may protrude from the negative electrode sheet 120. In this case, the negative electrode tab 160 may protrude toward the bottom surface of the cap assembly 12 or the battery case 11.

[0126] In addition, the negative electrode tab 160 may include a first negative electrode tab 161 provided in the first negative electrode uncoated portion 123a, a second negative electrode tab 162 provided in the second negative electrode uncoated portion 123b, and a third negative electrode tab 163 provided in the third negative electrode uncoated portion 123c.

[0127] In this case, the first positive electrode uncoated portion 113a and the first negative electrode uncoated portion 123a may be formed at positions corresponding to each other.

[0128] Also, referring to FIG. 5, the first positive electrode tab 151 and the first negative electrode tab 161 may be provided so as not to overlap with each other in the direction in which the positive electrode sheet 110 and the negative electrode sheet 120 face each other.

[0129] Meanwhile, referring to FIGS. 3 and 6, in the electrode assembly 100 of the secondary battery 10 according to the embodiment of the present invention, a first negative electrode insulating tape 181 may be further attached to the first negative electrode uncoated portion 123a so as to cover the first negative electrode tab 161.

[0130] In the electrode assembly 100 of the secondary battery 10 according to the embodiment of the present invention, a lithium ion deposition prevention tape 190 may be further attached to a portion of the positive electrode sheet 110 facing the first negative electrode uncoated portion 123a.

[0131] As a result, lithium ions are not exchanged in the portion of the positive electrode sheet 110 facing the first negative electrode uncoated portion 123a to which the first negative electrode insulating tape 181 is attached during charging and discharging, so that it is possible to prevent the lithium ions from accumulating and being precipitated.

[0132] That is, by attaching the lithium ion precipitation prevention tape 190 to the surface of the positive electrode active material part 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181, lithium ions are exchanged between the positive electrode sheet 110 and the negative electrode sheet 120, and it is possible to prevent lithium ions from accumulating and being precipitated in the parts where the lithium ions are not exchanged by the first negative electrode insulating tape 181 during charging and discharging.

[0133] FIG. 10 is a perspective view showing a state in which the positive and negative electrode plates are spread out before being wound up in an electrode assembly according to a fourth embodiment of the present invention.

[0134] Hereinafter, an electrode assembly according to a fourth embodiment of the present invention will be described with reference to FIG.

[0135] Referring to FIG. 10, an electrode assembly 1100 according to the fourth embodiment of the present invention includes a positive electrode plate 1110 including a positive electrode active material portion 1112 and a positive electrode uncoated portion 1113, a positive electrode tab 1150 provided on the positive electrode uncoated portion 1113, a negative electrode plate 1120 including a negative electrode active material portion 1122 and a negative electrode uncoated portion 1123, a negative electrode tab 1160 provided on the negative electrode uncoated portion 1123, and a separator 1140 provided between the positive electrode plate 1110 and the negative electrode plate 1120.

[0136] The electrode assembly 1100 is a power generating element capable of charging and discharging, and has a structure in which electrodes 1130 and separators 1140 are assembled and alternately stacked. Here, the electrode assembly 1100 is an electrode assembly 1100 for a lithium ion secondary battery, and may have a wound form.

[0137] The electrodes 1130 may include a positive plate 1110 and a negative plate 1120. And, a separator 1140 may separate and electrically insulate the positive plate 1110 and the negative plate 1120.

[0138] The positive electrode plates 1110 and the negative electrode plates 1120 may be alternately stacked and wound together with the separator 1140 into a roll shape. Here, the electrode assembly 1100 may be wound into, for example, a circular or elliptical shape, forming a jelly roll type.

[0139] The positive electrode plate 1110 may include a positive electrode current collector 1111, a positive electrode active material portion 1112 which is a region formed by stacking a positive electrode active material on the positive electrode current collector 1111, and a positive electrode uncoated portion 1113 which is a region where the positive electrode active material is not stacked.

[0140] The positive electrode current collector 1111 may be made of, for example, aluminum (Al) foil.

[0141] The positive electrode active material part 1112 may be formed to include a positive electrode active material laminated on a first surface M12 of the positive electrode current collector 1111. The positive electrode active material part 1112 may be formed to further include a positive electrode active material laminated on a second surface M12 of the positive electrode current collector 1111. The positive electrode active material part 1112 may be formed to further include a binder and a conductive material in addition to the positive electrode active material.

[0142] For example, the positive electrode uncoated portion 1113 may be formed in two parts spaced apart from each other and may include a first positive electrode uncoated portion 1113a and a second positive electrode uncoated portion 1113b. Here, the first positive electrode uncoated portion 1113a may be located between both ends of the positive electrode plate 1110.

[0143] Meanwhile, as another example, the positive electrode uncoated portion 1113 may be formed in three parts spaced apart from each other, and may include a first positive electrode uncoated portion 1113a, a second positive electrode uncoated portion 1113b, and a third positive electrode uncoated portion 1113c. In this case, the first positive electrode uncoated portion 1113a may be located between both ends of the positive electrode plate 1110.

[0144] The positive electrode tab 1150 may be provided in the positive electrode uncoated portion 1113 of the positive electrode plate 1110. In addition, the positive electrode tab 1150 may include a first positive electrode tab 1151 provided in the first positive electrode uncoated portion 1113a. Here, one end of the first positive electrode tab 1151 may be attached and fixed to the first positive electrode uncoated portion 1113a, and the other end may protrude from the positive electrode plate 1110. In addition, the positive electrode tab 1150 may further include a second positive electrode tab (not shown) provided in the second positive electrode uncoated portion 1113b.

[0145] The negative electrode plate 1210 may include a negative electrode current collector 1121, a negative electrode active material portion 1122 which is a region formed by stacking a negative electrode active material on the negative electrode current collector 1121, and a negative electrode uncoated portion 1123 which is a region where the negative electrode active material is not stacked.

[0146] The negative electrode current collector 1121 may be, for example, a foil made of copper (Cu) or nickel (Ni).

[0147] The negative electrode active material part 1122 may be formed by including a negative electrode active material laminated on the first surface M21 of the negative electrode current collector 1121. Here, the first surface M21 of the negative electrode current collector 1121 may be a surface facing the first surface M12 of the positive electrode current collector 1111. That is, in FIG. 10, for convenience of explanation, the first surface M21 of the negative electrode current collector 1122 is shown facing the same direction as the first surface M12 of the positive electrode current collector 1111, but the first surface M21 of the negative electrode current collector 1121 actually means a surface facing the first surface M12 of the positive electrode current collector 1111. The negative electrode active material part 1122 may be formed by further including a negative electrode active material laminated on the second surface of the negative electrode current collector 1121. The negative electrode active material part 1122 may be formed by further including a binder and a conductive material in addition to the negative electrode active material.

[0148] The negative electrode uncoated portion 1123 may include a first negative electrode uncoated portion 1123a formed between both ends of the negative electrode plate 1120, and a second negative electrode uncoated portion 1123b and a third negative electrode uncoated portion 1123c formed at both ends of the negative electrode plate 1120.

[0149] The first positive electrode uncoated portion 1113a and the first negative electrode uncoated portion 1123a may be formed at positions corresponding to each other.

[0150] The negative electrode tab 1160 is provided in the negative electrode uncoated portion 1123, and one end of the negative electrode tab 1160 may be attached and fixed to the negative electrode uncoated portion 1123 and the other end may protrude from the negative electrode plate 1120. In addition, the negative electrode tab 1160 may include a first negative electrode tab 1161 provided in the first negative electrode uncoated portion 1123a, a second negative electrode tab 1152 provided in the second negative electrode uncoated portion 1123b, and a third negative electrode tab 1153 provided in the third negative electrode uncoated portion 1123c.

[0151] The separators 1140 are made of an insulating material and are alternately stacked with the positive electrode plates 1110 and the negative electrode plates 1120. Here, the separators 1140 may be located between the positive electrode plates 1110 and the negative electrode plates 1120 and on the outer surfaces of the positive electrode plates 1110 or the negative electrode plates 1120.

[0152] Meanwhile, the first positive electrode tab 1151 and the first negative electrode tab 1161 may be provided so as not to overlap with each other in a direction in which the positive electrode plate 1110 and the negative electrode plate 1120 face each other. Here, the direction in which the positive electrode plate 1110 and the negative electrode plate 1120 face each other may be, for example, a lateral direction of the winding central axis. Ends of the first positive electrode tab 1151 and the first negative electrode tab 1161 may be positioned at a predetermined distance from each other based on a direction parallel to the winding central axis so as not to overlap with each other.

[0153] Meanwhile, in the electrode assembly 1100 according to the fourth embodiment of the present invention, a positive electrode insulating tape may be further attached to the positive electrode uncoated portion 1113 to cover the positive electrode tab 1150, and a negative electrode insulating tape may be further attached to the negative electrode uncoated portion 1123 to cover the negative electrode tab 1160. Here, the positive electrode insulating tape and the negative electrode insulating tape may be attached in the same form as the positive electrode insulating tape 170 and the negative electrode insulating tape 180 of the electrode assembly 100 according to the first embodiment of the present invention described above (see FIG. 2).

[0154] The positive electrode insulating tape may include a first positive electrode insulating tape attached to the first positive electrode uncoated portion 1113 a so as to cover the first positive electrode tab 1151 .

[0155] The negative electrode insulating tape may include a first negative electrode insulating tape attached to the first negative electrode uncoated portion 1213a to cover the first negative electrode tab 161, a second negative electrode insulating tape attached to the second negative electrode uncoated portion 1123b to cover the second negative electrode tab 1162, and a third negative electrode insulating tape attached to the third negative electrode uncoated portion 1123c to cover the third negative electrode tab 1163.

[0156] The positive electrode insulating tape and the negative electrode insulating tape may be formed of an electrically insulating material.

[0157] Meanwhile, in the electrode assembly 1100 according to the fourth embodiment of the present invention, a lithium ion deposition prevention tape including an insulating material may be further attached to a portion of the positive electrode plate 1110 facing the first negative electrode insulating tape with the separator 1140 interposed therebetween. Here, the lithium ion deposition prevention tape may be attached in the same form as the lithium ion deposition prevention tape 190 of the electrode assembly 100 according to the first embodiment of the present invention described above (see FIG. 2). Here, the lithium ion deposition prevention tape may be positioned, for example, on the surface of the positive electrode active material part 1112 of the positive electrode plate 1110. As a result, the lithium ion deposition prevention tape 1190 is positioned in the portion of the positive electrode plate 1110 facing the first negative electrode uncoated part 1123a to which the first negative electrode insulating tape is attached during charging and discharging, and thus lithium ions are not exchanged, so that it is possible to prevent lithium ions from accumulating and being deposited.

[0158] <Production Example> 1-1 Manufacturing of electrode assembly Positive electrode uncoated portions were formed on two portions of the positive electrode sheet that were spaced apart from each other, and positive electrode tabs were provided on each of the positive electrode uncoated portions, and negative electrode tabs were provided on three portions of the negative electrode sheet that were spaced apart from each other, thereby preparing an electrode assembly having two positive electrode tabs and three negative electrode tabs.

[0159] At this time, a first positive electrode uncoated portion was formed in the two positive electrode uncoated portions of the positive electrode sheet, and a first negative electrode uncoated portion was formed between both sides of the negative electrode sheet at positions corresponding to each other.

[0160] 1-2 Manufacturing of secondary batteries The manufactured electrode assembly was placed in a battery case together with an electrolyte to manufacture a secondary battery.

[0161] <Comparative Example> A secondary battery was manufactured in the same manner as in the above Manufacturing Example, except that a positive electrode uncoated portion was formed on two portions of a positive electrode sheet that were spaced apart from each other, and a negative electrode uncoated portion was formed on two portions of a negative electrode sheet that were spaced apart from each other, and a negative electrode tab was provided on each portion, thereby manufacturing an electrode assembly having two positive electrode tabs and two negative electrode tabs. Here, in the Comparative Example, a negative electrode uncoated portion was formed on two portions of the negative electrode sheet, and the first negative electrode uncoated portion formed between both sides of the negative electrode sheet in the Manufacturing Example was not formed.

[0162] <Experimental Example> The effect of improving resistance was measured by applying electricity to the secondary battery.

[0163] As a result of AC (alternating current) resistance measurement, it was observed that the resistance value measured in the manufacturing example was about 20% lower than that measured in the comparative example.

[0164] In conclusion, it can be seen that the resistance of the manufacturing example is significantly improved.

[0165] Although the present invention has been described in detail above through specific embodiments, this is for the purpose of specifically explaining the present invention, and the electrode assembly and the secondary battery including the same according to the present invention are not limited thereto. It can be said that various implementations are possible by those having ordinary skill in the art within the technical concept of the present invention.

[0166] Furthermore, the specific scope of protection of the invention will be clarified by the claims. The following items are also disclosed: [Item 1] An electrode assembly comprising: a positive electrode sheet including a positive electrode active material portion which is a region formed by laminating a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion which is a region where the positive electrode active material is not laminated; a positive electrode tab provided on the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion which is a region formed by laminating a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion which is a region where the negative electrode active material is not laminated; a negative electrode tab provided on the negative electrode uncoated portion; and a separator for insulating the positive electrode sheet and the negative electrode sheet, The positive electrode uncoated portion includes a first positive electrode uncoated portion and a second positive electrode uncoated portion formed in two portions spaced apart from each other on the positive electrode sheet, the negative electrode uncoated portion includes a first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, and a second negative electrode uncoated portion and a third negative electrode uncoated portion formed on both side portions of the negative electrode sheet, the first positive electrode uncoated portion or the second positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, forming an electrode assembly. [Item 2] the positive electrode tab includes a first positive electrode tab provided in the first positive electrode uncoated portion and a second positive electrode tab provided in the second positive electrode uncoated portion, 2. The electrode assembly of item 1, wherein the negative electrode tabs include a first negative electrode tab provided in the first negative electrode uncoated area, a second negative electrode tab provided in the second negative electrode uncoated area, and a third negative electrode tab provided in the third negative electrode uncoated area. [Item 3] The electrode assembly is an electrode assembly for a lithium ion secondary battery, The positive electrode sheet, the separator, and the negative electrode sheet are alternately stacked and wound up, a first negative electrode insulating tape is further attached to the first negative electrode uncoated portion to cover the first negative electrode tab; 3. The electrode assembly of item 2, wherein a lithium ion deposition prevention tape is further attached to a portion of the positive electrode sheet facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging. [Item 4] The separator includes an insulating material having pores through which the lithium ions can move, 4. The electrode assembly of item 3, wherein the first negative electrode insulating tape and the lithium ion deposition prevention tape include an insulating material. [Item 5] The positive electrode sheet and the negative electrode sheet are wound clockwise at both sides, one side of which is positioned at a winding outer periphery and the other side of which is positioned at a winding center. 5. The electrode assembly of claim 3 or 4, wherein the first positive electrode uncoated portion and the second positive electrode uncoated portion are formed between both side portions of the positive electrode sheet, and the first positive electrode uncoated portion or the second positive electrode uncoated portion formed at a position corresponding to the first negative electrode uncoated portion is located on one side of the positive electrode sheet. [Item 6] 6. The electrode assembly of item 5, wherein one surface of each of the positive electrode sheet and the negative electrode sheet is positioned toward the inside when wound, and the other surface is positioned toward the outside of the winding side. [Item 7] The positive electrode sheet and the negative electrode sheet are wound clockwise from the other side of the both sides, with the other side being positioned at the winding center and the one side being positioned at the winding outer periphery, 4. The electrode assembly of item 3, wherein the first positive electrode uncoated portion and the second positive electrode uncoated portion are formed between both side portions of the positive electrode sheet, and at this time, the first positive electrode uncoated portion is positioned on one side of the positive electrode sheet. [Item 8] 8. The electrode assembly of item 7, wherein one surface of each of the positive electrode sheet and the negative electrode sheet is positioned toward the outside when wound, and the other surface is positioned toward the inside of the winding side. [Item 9] The electrode assembly of item 6 or item 8, wherein the lithium ion deposition prevention tape is provided on the other surface of the positive electrode sheet, and is positioned on a surface of the positive electrode active material portion laminated between one side of the positive electrode sheet and the first positive electrode uncoated portion located near the one side of the positive electrode sheet. [Item 10] The separator includes a first separator disposed between one surface of the positive electrode sheet and the other surface of the negative electrode sheet; and a second separator located on one surface of the negative electrode sheet; 10. The electrode assembly of item 9, wherein the first negative electrode uncoated portion and the lithium ion deposition prevention tape face each other with the second separator interposed therebetween. [Item 11] 9. The electrode assembly of any one of items 2 to 8, wherein the first positive electrode tab and the first negative electrode tab are provided so as not to overlap each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other. [Item 12] The first positive electrode tab protrudes toward one side in a direction parallel to a winding central axis, The first negative electrode tab protrudes toward the other side based on a direction parallel to the winding central axis, Item 12. The electrode assembly of item 11, wherein ends of the first positive electrode tab and the first negative electrode tab are positioned at a predetermined distance from each other in a direction parallel to the winding central axis so as not to overlap each other. [Item 13] An electrode assembly comprising: a positive electrode sheet including a positive electrode active material portion which is a region formed by laminating a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion which is a region where the positive electrode active material is not laminated; a positive electrode tab provided on the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion which is a region formed by laminating a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion which is a region where the negative electrode active material is not laminated; a negative electrode tab provided on the negative electrode uncoated portion; and a separator for insulating the positive electrode sheet and the negative electrode sheet, the positive electrode uncoated portion includes a first positive electrode uncoated portion formed on the positive electrode sheet, and the negative electrode uncoated portion includes a first negative electrode uncoated portion formed on the negative electrode sheet, in which the first positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, the positive electrode tab includes a first positive electrode tab provided in the first positive electrode uncoated portion, and the negative electrode tab includes a first negative electrode tab provided in the first negative electrode uncoated portion, wherein the first positive electrode tab and the first negative electrode tab are not overlapped with each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other. [Item 14] The first positive electrode tab protrudes toward one side in a direction parallel to a winding central axis, The first negative electrode tab protrudes toward the other side based on a direction parallel to the winding central axis, Item 14. The electrode assembly of item 13, wherein ends of the first positive electrode tab and the first negative electrode tab are positioned at a predetermined distance from each other in a direction parallel to the winding central axis so as not to overlap each other. [Item 15] An electrode assembly comprising: a positive electrode plate including a positive electrode active material portion in which a positive electrode active material is applied on a first surface of a positive electrode current collector, and a first positive electrode uncoated portion which is an area in which the positive electrode active material is not applied; a positive electrode tab attached to the first positive electrode uncoated portion; a negative electrode plate including a negative electrode active material portion in which a negative electrode active material is applied on a first surface of a negative electrode current collector opposite to the first surface of the positive electrode current collector, and a first negative electrode uncoated portion which is an area in which the negative electrode active material is not applied; and a separator between the positive plate and the negative plate; the first positive electrode uncoated portion is located between one end and the other end of the positive electrode plate along a longitudinal direction of the positive electrode plate, and the first negative electrode uncoated portion is formed at a position overlapping the first positive electrode uncoated portion, the first negative electrode uncoated portion is formed between a second negative electrode uncoated portion and a third negative electrode uncoated portion, the second negative electrode uncoated portion and the third negative electrode uncoated portion being formed on both sides of the negative electrode plate and having a negative electrode tab attached thereto; The electrode assembly further includes a negative electrode tab provided on the first negative electrode uncoated portion. [Item 16] the positive electrode plate further includes a second positive electrode uncoated portion, which is a region where the positive electrode active material is not applied, and the positive electrode tab is further attached to the second positive electrode uncoated portion; Item 16. The electrode assembly of item 15, wherein the negative electrode plate further includes a second negative electrode uncoated portion and a third negative electrode uncoated portion which are areas where the negative electrode active material is not applied, and the negative electrode tab is further attached to the second negative electrode uncoated portion and the third negative electrode uncoated portion. [Item 17] The electrode assembly is an electrode assembly for a lithium ion secondary battery, The positive electrode plate, the separator, and the negative electrode plate are alternately stacked and wound up, a first negative electrode insulating tape is further attached to the first negative electrode uncoated portion so as to cover the negative electrode tab attached to the first negative electrode uncoated portion; Item 17. The electrode assembly of item 16, further comprising a lithium ion deposition prevention tape attached to a portion of the positive electrode plate facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging. [Item 18] the first negative electrode uncoated portion and the lithium ion precipitation prevention tape are opposed to each other with the separator interposed therebetween, Item 18. The electrode assembly of item 17, wherein the lithium ion deposition prevention tape is positioned on a surface of the positive electrode active material portion of the positive electrode plate. [Item 19] 19. The electrode assembly of any of items 15 to 18, wherein the positive electrode tab attached to the first positive electrode uncoated portion and the negative electrode tab attached to the first negative electrode uncoated portion are provided so as not to overlap with each other in a direction in which the positive electrode plate and the negative electrode plate face each other. [Item 20] an electrode assembly and a battery case that houses the electrode assembly, 20. A secondary battery, wherein the electrode assembly is any one of the electrode assemblies of items 1 to 19.

Claims

1. An electrode assembly comprising: a positive electrode sheet including a positive electrode active material portion which is a region formed by laminating a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion which is a region where the positive electrode active material is not laminated; a positive electrode tab provided on the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion which is a region formed by laminating a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion which is a region where the negative electrode active material is not laminated; a negative electrode tab provided on the negative electrode uncoated portion; and a separator for insulating the positive electrode sheet and the negative electrode sheet, The positive electrode uncoated portion includes a first positive electrode uncoated portion and a second positive electrode uncoated portion formed as two portions spaced apart from each other on the positive electrode sheet, the negative electrode uncoated portion includes a first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, and a second negative electrode uncoated portion and a third negative electrode uncoated portion formed on both side portions of the negative electrode sheet, the first positive electrode uncoated region or the second positive electrode uncoated region and the first negative electrode uncoated region are formed at positions corresponding to each other, the positive electrode tab includes a first positive electrode tab provided in the first positive electrode uncoated region and a second positive electrode tab provided in the second positive electrode uncoated region, and the negative electrode tab includes a first negative electrode tab provided in the first negative electrode uncoated region, When the first positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, the first positive electrode tab and the first negative electrode tab are provided so as not to overlap each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other, an electrode assembly including: a first electrode tab and a second electrode tab arranged so as not to overlap each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other, when the second positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other;

2. The electrode assembly of claim 1 , wherein the negative electrode tabs include a second negative electrode tab provided in the second negative electrode uncoated portion and a third negative electrode tab provided in the third negative electrode uncoated portion.

3. The electrode assembly is an electrode assembly for a lithium ion secondary battery, The positive electrode sheet, the separator, and the negative electrode sheet are alternately stacked and wound up, a first negative electrode insulating tape is further attached to the first negative electrode uncoated portion to cover the first negative electrode tab; 3. The electrode assembly of claim 2, further comprising a lithium ion deposition prevention tape attached to a portion of the positive electrode sheet facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging.

4. The separator includes an insulating material having pores through which the lithium ions can move, The electrode assembly of claim 3 , wherein the first negative electrode insulating tape and the lithium ion deposition prevention tape include an insulating material.

5. The positive electrode sheet and the negative electrode sheet are wound clockwise at both sides, one side of which is positioned at a winding outer periphery and the other side of which is positioned at a winding center.

5. The electrode assembly of claim 3, wherein the first positive electrode uncoated portion and the second positive electrode uncoated portion are formed between both side portions of the positive electrode sheet, and the first positive electrode uncoated portion or the second positive electrode uncoated portion formed at a position corresponding to the first negative electrode uncoated portion is located on one side of the positive electrode sheet.

6. 6. The electrode assembly according to claim 5, wherein one surface of each of the positive and negative electrode sheets faces inward when wound, and the other surface faces outward when wound.

7. The positive electrode sheet and the negative electrode sheet are wound clockwise from the other side of the both sides, with the other side being positioned at the winding center and the one side being positioned at the winding outer periphery, 4. The electrode assembly of claim 3, wherein the first positive electrode uncoated region and the second positive electrode uncoated region are formed between both side portions of the positive electrode sheet, and the first positive electrode uncoated region is located on one side of the positive electrode sheet.

8. 8. The electrode assembly according to claim 7, wherein one surface of each of the positive and negative electrode sheets faces outward when wound, and the other surface faces inward when wound.

9. 9. The electrode assembly of claim 6, wherein the lithium ion deposition prevention tape is provided on the other surface of the positive electrode sheet, and is positioned on a surface of the positive electrode active material portion laminated between one side of the positive electrode sheet and the first positive electrode uncoated portion located near the one side of the positive electrode sheet.

10. The separator includes a first separator disposed between one surface of the positive electrode sheet and the other surface of the negative electrode sheet; and a second separator disposed on one surface of the negative electrode sheet; The electrode assembly of claim 9 , wherein the first negative electrode uncoated portion and the lithium ion deposition prevention tape face each other with the second separator interposed therebetween.

11. The first positive electrode tab protrudes toward one side based on a direction parallel to a winding central axis, The first negative electrode tab protrudes toward the other side based on a direction parallel to the winding central axis, 9. The electrode assembly of claim 1, wherein ends of the first positive electrode tab and the first negative electrode tab are spaced a predetermined distance from each other in a direction parallel to the winding central axis so as not to overlap each other.

12. An electrode assembly comprising: a positive electrode sheet including a positive electrode active material portion which is a region formed by laminating a positive electrode active material on a positive electrode current collector, and a positive electrode uncoated portion which is a region where the positive electrode active material is not laminated; a positive electrode tab provided on the positive electrode uncoated portion; a negative electrode sheet including a negative electrode active material portion which is a region formed by laminating a negative electrode active material on a negative electrode current collector, and a negative electrode uncoated portion which is a region where the negative electrode active material is not laminated; a negative electrode tab provided on the negative electrode uncoated portion; and a separator for insulating the positive electrode sheet and the negative electrode sheet, the positive electrode uncoated portion includes a first positive electrode uncoated portion formed on the positive electrode sheet, and the negative electrode uncoated portion includes a first negative electrode uncoated portion formed between both ends of the negative electrode sheet, in which the first positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, the positive electrode tab includes a first positive electrode tab provided in the first positive electrode uncoated portion, and the negative electrode tab includes a first negative electrode tab provided in the first negative electrode uncoated portion, wherein the first positive electrode tab and the first negative electrode tab are not overlapped with each other in a direction in which the positive electrode sheet and the negative electrode sheet face each other.

13. The first positive electrode tab protrudes toward one side based on a direction parallel to a winding central axis, The first negative electrode tab protrudes toward the other side based on a direction parallel to the winding central axis, 13. The electrode assembly of claim 12, wherein ends of the first positive electrode tab and the first negative electrode tab are spaced apart from each other by a predetermined distance in a direction parallel to the winding central axis so as not to overlap each other.

14. An electrode assembly comprising: a positive electrode plate including a positive electrode active material portion in which a positive electrode active material is applied on a first surface of a positive electrode current collector, and a first positive electrode uncoated portion which is an area in which the positive electrode active material is not applied; a positive electrode tab attached to the first positive electrode uncoated portion; a negative electrode plate including a negative electrode active material portion in which a negative electrode active material is applied on a first surface of a negative electrode current collector opposite to the first surface of the positive electrode current collector, and a first negative electrode uncoated portion which is an area in which the negative electrode active material is not applied; and a separator between the positive plate and the negative plate; the first positive electrode uncoated portion is located between one end and the other end of the positive electrode plate along a longitudinal direction of the positive electrode plate, and the first negative electrode uncoated portion is formed at a position overlapping the first positive electrode uncoated portion, the first negative electrode uncoated portion is formed between a second negative electrode uncoated portion and a third negative electrode uncoated portion, the second negative electrode uncoated portion and the third negative electrode uncoated portion being formed on both sides of the negative electrode plate and having a negative electrode tab attached thereto; a negative electrode tab provided on the first negative electrode uncoated portion, the positive electrode tab attached to the first positive electrode uncoated portion and the negative electrode tab attached to the first negative electrode uncoated portion are arranged so as not to overlap with each other in a direction in which the positive electrode plate and the negative electrode plate face each other.

15. the positive electrode plate further includes a second positive electrode uncoated portion which is a region where the positive electrode active material is not applied, and the positive electrode tab is further attached to the second positive electrode uncoated portion; 15. The electrode assembly of claim 14, wherein the negative electrode plate further includes a second negative electrode uncoated portion and a third negative electrode uncoated portion which are areas where the negative electrode active material is not applied, and the negative electrode tab is further attached to the second negative electrode uncoated portion and the third negative electrode uncoated portion.

16. The electrode assembly is an electrode assembly for a lithium ion secondary battery, The positive electrode plate, the separator, and the negative electrode plate are alternately stacked and wound up, a first negative electrode insulating tape is further attached to the first negative electrode uncoated portion to cover the negative electrode tab attached to the first negative electrode uncoated portion; 16. The electrode assembly of claim 15, further comprising a lithium ion deposition prevention tape attached to a portion of the positive electrode plate facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging.

17. the first negative electrode uncoated portion and the lithium ion deposition prevention tape are opposed to each other with the separator interposed therebetween, The electrode assembly according to claim 16 , wherein the lithium ion deposition prevention tape is positioned on a surface of the positive electrode active material portion of the positive electrode plate.

18. an electrode assembly and a battery case that houses the electrode assembly, The electrode assembly is the electrode assembly according to claim 1 .

Images