Title of the invention: electrode assembly and secondary battery including the same
Technical field
[One]
Mutual citation with related applications
[2]
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 04, 2019. All contents disclosed in the literature are included as part of this specification.
[3]
Technical field
[4]
The present invention relates to an electrode assembly and a secondary battery including the same.
Background
[5]
Unlike primary batteries, secondary batteries can be recharged, and due to their small size and high capacity, many research and developments have been made in recent years. As technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing.
[6]
Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries according to the shape of the battery case. In a secondary battery, an electrode assembly mounted inside a battery case is a power plant capable of charging and discharging having a stacked structure of electrodes and separators.
[7]
The electrode assembly is a jelly-roll type in which a separator is interposed between the positive electrode and the negative electrode in a sheet type coated with an active material, and a stack type in which a plurality of positive and negative electrodes are sequentially stacked with a separator interposed therebetween. , And stacked unit cells may be roughly classified into a stack/folding type wound with a long-length separation film. The double jelly roll type electrode assembly is widely used because it is easy to manufacture and has a high energy density per weight.
Detailed description of the invention
Technical challenge
[8]
One aspect of the present invention is to provide an electrode assembly capable of reducing resistance and a secondary battery including the same.
[9]
In addition, 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 of solving the task
[10]
The electrode assembly according to the first embodiment of the present invention is an electrode assembly, comprising: 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 in which the positive electrode active material is not laminated. A negative electrode sheet including a sheet, a positive electrode tab provided in the positive electrode uncoated part, a negative electrode active material part which is a region formed by stacking a negative electrode active material on the negative electrode current collector, and a negative negative electrode uncoated part which is a region in which the negative active material is not laminated, A negative electrode tab provided in the negative electrode uncoated portion, and a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein the positive electrode uncoated portion is formed at two portions spaced apart from each other in the positive electrode sheet, and a first positive electrode uncoated portion and a second A positive electrode uncoated portion, wherein 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 sides of the negative electrode sheet, and the second negative electrode uncoated portion The first anode uncoated portion and the first cathode uncoated portion may be formed at positions corresponding to each other.
[11]
And, a secondary battery according to an embodiment of the present invention includes an electrode assembly and a battery case accommodating the electrode assembly, wherein the electrode assembly includes a positive electrode current collector, a positive electrode active material stacked on the positive electrode current collector, and the positive electrode. A positive electrode sheet including a positive electrode uncoated portion, which is an area in which an active material is unlaminated, a positive electrode tab provided in the positive electrode uncoated portion, a negative electrode current collector, a negative active material stacked on the negative electrode current collector, and a region in which the negative active material is not laminated A negative electrode sheet including a phosphorus negative electrode uncoated portion, a negative electrode tab provided on the negative electrode sheet, and a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein the positive electrode non-coated portion is formed in two portions of the positive electrode sheet And a second uncoated portion and a second uncoated portion, wherein the uncoated portion of the negative electrode includes a first uncoated portion formed between both sides of the negative electrode sheet, and a second uncoated portion and a third uncoated portion formed on both sides of the negative electrode sheet. And the first anode uncoated portion and the first cathode uncoated portion may be formed at positions corresponding to each other.
[12]
In addition, the electrode assembly according to the second embodiment of the present invention is an electrode assembly, comprising: a positive electrode active material portion coated with a positive electrode active material on a first surface of a positive electrode current collector, and a first positive electrode uncoated area in which the positive electrode active material is not applied. A positive electrode plate including a portion, a positive electrode tab attached to the first positive electrode uncoated portion, a negative active material portion coated with a negative electrode active material on a first surface of the negative electrode current collector facing the first surface of the positive electrode current collector, and the A negative electrode plate including a first negative electrode uncoated portion, which is a region not coated with a negative electrode active material, and a separator between the positive electrode plate and the negative electrode plate, wherein the first positive electrode uncoated portion comprises one end of the positive electrode plate along a length direction of the positive electrode plate. Located between the other ends, the first anode uncoated portion is formed at a position overlapping the first anode uncoated portion, and the first cathode uncoated portion is formed on both sides of the cathode plate, and a second anode uncoated portion to which a cathode tab is attached. It may further include a negative electrode tab formed between the negative and the third negative electrode uncoated portion and provided in the first negative electrode uncoated portion.
[13]
In addition, the electrode assembly according to the third embodiment of the present invention, as an electrode assembly, includes 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 in which the positive electrode active material is not laminated. A negative electrode sheet comprising a positive electrode sheet, a positive electrode tab provided on the positive electrode uncoated portion, a negative electrode active material portion, which is a region formed by stacking a negative electrode active material on the negative electrode current collector, and a negative negative electrode uncoated portion, which is a region in which the negative active material is not stacked. And, a negative electrode tab provided in the negative electrode uncoated portion, and a separator insulating between the positive electrode sheet and the negative electrode sheet, the positive electrode non-coating portion including a first positive electrode non-coating portion formed on the positive electrode sheet, and the negative electrode non-coating portion Including a first negative electrode uncoated portion formed on the negative electrode sheet, wherein the first positive electrode uncoated portion and the first negative electrode uncoated portion are formed at positions corresponding to each other, and the positive electrode tab is a first positive electrode tab provided in the first positive electrode uncoated portion Including, wherein the negative electrode tab includes a first negative electrode tab provided on the first negative electrode uncoated portion, wherein the first positive electrode tab and the first negative electrode tab are in a direction in which the positive electrode sheet and the negative electrode sheet face each other. It may be provided so as not to overlap each other.
[14]
In addition, the electrode assembly according to the fourth embodiment of the present invention is an electrode assembly, comprising: a positive electrode active material portion coated with a positive electrode active material on a first surface of a positive electrode current collector, and a first positive electrode plain material, which is an area where the positive electrode active material A positive electrode plate including a portion, a positive electrode tab attached to the first positive electrode uncoated portion, a negative active material portion coated with a negative electrode active material on a first surface of the negative electrode current collector facing the first surface of the positive electrode current collector, and the A negative electrode plate including a first negative electrode uncoated portion, which is a region not coated with a negative electrode active material, and a separator between the positive electrode plate and the negative electrode plate, and the first positive electrode uncoated portion Located between the ends, the first negative uncoated portion is formed at a position overlapping with the first positive uncoated portion, and the first negative uncoated portion is formed on both sides of the negative electrode plate, and a second negative uncoated portion to which a negative electrode tab is attached And a negative electrode tab formed between the third negative electrode uncoated portion and provided in the first negative negative electrode uncoated portion.
Effects of the Invention
[15]
According to the present invention, it is possible to decrease the resistance by increasing the number of electrode taps. In this case, resistance can be minimized by increasing the number of negative electrode tabs so that the number of negative electrode tabs is greater than the number of positive electrode tabs.
[16]
In addition, according to the present invention, the negative electrode uncoated portion in which the added negative electrode tab is positioned and the positive uncoated portion in which the positive electrode tab is positioned are formed at corresponding positions, thereby minimizing capacity loss. At this time, it is possible to avoid overlapping between the positive electrode tab and the negative electrode tab in a direction opposite to each other by separating the distance between the ends of the positive electrode tab and the added negative electrode tab provided in the positive electrode uncoated part have. Accordingly, it is possible to prevent uneven winding when winding the positive electrode sheet and the negative electrode sheet.
[17]
In addition, it is possible to prevent lithium ions from accumulating and depositing by placing a lithium ion precipitation prevention tape on a portion of the positive electrode sheet facing the negative electrode insulating tape covering the added negative electrode tab.
Brief description of the drawing
[18]
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.
[19]
2 is a partial perspective view showing another arrangement example of the positive electrode tab in the electrode assembly according to the first embodiment of the present invention.
[20]
3 is a front view showing an unfolded state before the electrode assembly according to the first embodiment of the present invention is wound.
[21]
4 is a plan view showing a stacked state before the electrode assembly according to the first embodiment of the present invention is wound.
[22]
5 is a plan view showing an unfolded state before a positive electrode sheet and a negative electrode sheet are wound in the electrode assembly according to the first embodiment of the present invention.
[23]
6 is a partial front view showing a main part of the invention in a state in which the electrode assembly according to the first embodiment of the present invention is wound.
[24]
7 is a front view showing an unfolded state before the electrode assembly according to the second embodiment of the present invention is wound.
[25]
8 is a front view showing an unfolded state before the electrode assembly according to the third embodiment of the present invention is wound.
[26]
9 is a partial front view showing a main part of the invention in a state in which the electrode assembly according to the third embodiment of the present invention is wound.
[27]
10 is a perspective view showing an unfolded state before a positive electrode plate and a negative electrode plate are wound in the electrode assembly according to the fourth embodiment of the present invention.
Mode for carrying out the invention
[28]
Objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the accompanying drawings. In the present specification, in adding reference numerals to elements of each drawing, it should be noted that only the same elements have the same number as possible, even if they are indicated on different drawings. In addition, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in describing the present invention, detailed descriptions of related known technologies that may unnecessarily obscure the subject matter of the present invention will be omitted.
[29]
[30]
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, and FIG. 2 is a partial perspective view showing another arrangement example of a positive electrode tab in the electrode assembly according to the first embodiment of the present invention 3 is a front view showing an unfolded state before the electrode assembly according to the first embodiment of the present invention is wound.
[31]
1 and 3, the electrode assembly 100 according to the 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, and a positive electrode uncoated portion. A negative electrode sheet 120 including a positive electrode tab 150 provided in 113, a negative electrode active material part 122 and a negative electrode uncoated part 123, and a negative electrode tab 160 provided in the negative electrode uncoated part 123 , And a separator 140 provided between the positive electrode sheet 110 and the negative electrode sheet 120.
[32]
[33]
4 is a plan view showing a stacked state before the electrode assembly according to the first embodiment of the present invention is wound, and FIG. 5 is a positive electrode sheet 110 and a negative electrode sheet in the electrode assembly according to the first embodiment of the present invention. 120) is a plan view showing an unfolded state before being wound, and FIG. 6 is a partial front view showing a main part of the present invention in a state in which the electrode assembly according to the first embodiment of the present invention is wound.
[34]
Hereinafter, an electrode assembly, which is a first embodiment of the present invention, will be described in more detail with reference to FIGS. 1 to 6.
[35]
[36]
1 and 3, the electrode assembly 100 is a power generating device capable of charging and discharging, and the electrode 130 and the separator 140 are assembled to form a structure in which the electrode 130 and the separator 140 are alternately stacked. Here, the electrode assembly 100 is an electrode assembly 100 for a lithium ion secondary battery, and may have a wound shape.
[37]
The electrode 130 may include a positive electrode sheet 110 and a negative electrode sheet 120. In addition, the separator 140 may separate the positive electrode sheet 110 and the negative electrode sheet 120 to be electrically insulated.
[38]
Further, the positive electrode sheet 110 and the negative electrode sheet 120 are alternately stacked and wound together with the separator 140, but may be formed in a roll shape. Here, the electrode assembly 100 may be wound in a circular or elliptical shape, for example, and formed in a jelly roll shape.
[39]
[40]
3 to 5, the positive electrode sheet 110 includes a positive electrode active material part 112 that is a region in which a positive electrode active material is stacked on the positive electrode current collector 111 and a positive electrode uncoated part 113 that is a region in which the positive electrode active material is not stacked ) Can be included. At this time, the positive electrode sheet 110 may be formed, for example, in a sheet form.
[41]
The positive electrode current collector 111 may be formed of, for example, a foil made of aluminum (Al).
[42]
The positive electrode active material part 112 may be formed by including a positive electrode active material laminated on one or more of the one surface 110c or the other surface 110d of the positive electrode sheet 110. In this case, the positive active material part 112 may be formed on both sides of the positive electrode sheet 120, for example. In addition, the positive active material part 112 may further include a binder and a conductive material in addition to the positive active material.
[43]
The positive electrode active material may be made of, for example, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a compound and mixture containing at least one of them.
[44]
In addition, the positive electrode active material may be made of a Hi Ni-based positive electrode material as another example. Here, the Hi Ni-based cathode material may include any one or more of LiNiMnCoO-based, LiNiCoAl-based, or LiMiMnCoAl-based.
[45]
The binder is, for example, polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, It may be made of any one of polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, or fluorine rubber.
[46]
The conductive material is, for example, graphite; Carbon blacks 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 whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Alternatively, it may be made of any one of conductive materials such as polyphenylene derivatives.
[47]
[48]
The anode uncoated portion 113 is formed of two portions spaced apart from each other, and may include a first anode uncoated portion 113a and a second anode uncoated portion 113b. Here, the anode uncoated portion 113 may be formed on one or more of both sides of the anode sheet 110.
[49]
The first anode uncoated portion 113a and the second anode uncoated portion 113b may be positioned between both side portions in the longitudinal direction of the anode sheet 110.
[50]
Here, the first anode uncoated portion 113a is positioned close to, for example, one side portion 110a of the anode sheet 110, and the second anode uncoated portion 113b is the other side portion 110b of the anode sheet 110 And can be located close to.
[51]
In addition, when the positive electrode sheet 110 is wound, the first positive electrode uncoated portion 113a may be positioned on the outer side of the winding, and the second positive electrode uncoated portion 113b may be positioned at the winding center side. However, the present invention is not necessarily limited thereto, for example, when the positive electrode sheet 110 is wound, the first positive electrode uncoated portion 113a is located at the center of the winding, and the second positive electrode uncoated portion 113b is It may be located on the outer side of the winding.
[52]
[53]
The positive electrode tab 150 is provided on the positive electrode uncoated portion 113 of the positive electrode sheet 110. Here, the positive electrode tab 150 may have one end attached and fixed to the positive electrode uncoated portion 113, and the other end may protrude from the positive electrode sheet 110.
[54]
In addition, the anode tab 150 may include a first anode tab 151 provided in the first anode uncoated portion 113a and a second anode tab 152 provided in the second anode uncoated portion 113b. . Here, the first positive electrode tab 151 and the second positive electrode tab 152 are illustrated as being positioned on the other surface 110d of the positive electrode sheet 110 in FIG. 3 as an example, but the present invention is necessarily limited thereto. In addition, 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.
[55]
[56]
Meanwhile, referring to FIG. 1, the first positive electrode tab 151 and the second positive electrode tab 152 may be positioned on both sides of the wound electrode assembly 100 with respect to the winding central axis C as an example.
[57]
Referring to FIG. 2, in the positive electrode tab 150, the first positive electrode tab 151 ′ and the second positive electrode tab 152 are at one side with respect to the winding central axis C in the wound electrode assembly 100 ′. Can be located in That is, the first positive electrode tab 151 ′ and the second positive electrode tab 152 may be sequentially arranged in the direction of the outer circumferential surface of the electrode assembly 100 ′ in the winding central axis C. 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.
[58]
[59]
3 to 5, the negative electrode sheet 120 includes a negative electrode active material part 122, which is a region in which a negative electrode active material is stacked on the negative electrode current collector 121, and a negative electrode uncoated part 123, which is a region in which the negative active material is not stacked. ) Can be included. At this time, the negative electrode sheet 120 may be formed, for example, in a sheet form.
[60]
The negative electrode current collector 121 may be made of a foil made of, for example, copper (Cu) or nickel (Ni).
[61]
The negative active material part 122 may be formed by including a negative active material laminated on one or more of the one surface 120c or the other surface 120d of the negative electrode sheet 120. In this case, the negative active material part 122 may be formed on both sides of the negative electrode sheet 120, for example. In addition, the negative active material part 122 may further include a binder and a conductive material in addition to the negative active material.
[62]
The negative active material may be made of, for example, a material including artificial graphite.
[63]
In addition, the negative electrode active material may be made of lithium metal, lithium alloy, carbon, petroleum coke, activated carbon, graphite, silicon compound, tin compound, titanium compound, or an alloy thereof as another example.
[64]
[65]
The negative electrode uncoated portion 123 includes a first negative electrode uncoated portion 123a formed between both side portions in the longitudinal direction of the negative electrode sheet 120, a second negative electrode uncoated portion 123b formed on both sides of the negative electrode sheet 120 A third negative electrode uncoated portion 123c may be included. Here, the negative electrode uncoated portion 123 may be formed on one or more of both surfaces of the negative electrode sheet 120.
[66]
Meanwhile, referring to FIGS. 3, 5 and 6, the first anode uncoated portion 113a and the first cathode uncoated portion 123a may be formed at positions corresponding to each other.
[67]
[68]
3 to 5, the negative electrode tab 160 is provided on the negative electrode uncoated part 123. Here, the negative electrode tab 160 may have one end attached and fixed to the negative electrode uncoated part 123, and the other end may protrude from the negative electrode sheet 120.
[69]
In addition, the negative electrode tab 160 includes a first negative electrode tab 161 provided in the first negative electrode uncoated part 123a, a second negative electrode tab 162 provided in the second negative negative electrode uncoated part 123b, and a third It may include a provided in the negative electrode uncoated portion (123c). Here, the first negative electrode tab 161 and the second negative electrode tab 162 are, for example, located on one surface (120c) of the negative electrode sheet 120 in FIG. 3, and are located on the other surface (120d) of the silver negative electrode sheet (120). Although shown as being shown, the present invention is not limited thereto, the first negative electrode tab 161, the second negative electrode tab 162, and the third negative electrode tab 163, respectively, one surface of the negative electrode sheet 120 ( 120c) or may be formed on the other surface (120d). At this time, as another example, the first negative electrode tab 161 and the second negative electrode tab 162 are located on the other surface 120d of the negative electrode sheet 120, and the third negative electrode tab 163 is one surface of the negative electrode sheet 120 ( 120c).
[70]
[71]
1, 3, and 6, the separator 140 is made of an insulating material and is alternately stacked with the positive electrode sheet 110 and the negative electrode sheet 120. Here, the separator 140 may be positioned 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.
[72]
In addition, the separation membrane 140 may be formed of, for example, a material having uniform micropores. Here, the separator 140 is specifically, for example, a multilayer film manufactured by polyethylene, polypropylene, or a combination thereof having microporosity, or polyvinylidene fluoride, polyethylene oxide, polyacrylonitrile, or polyvinylidene fluorine. It may be a polymer film for a solid polymer electrolyte or a gel polymer electrolyte, such as a lide hexafluoropropylene copolymer.
[73]
In addition, the separator 140 is located between the one surface (110c) of the anode sheet 110 and the other surface (120d) of the anode sheet 120, the first separator 141 and one surface (120c) of the negative electrode sheet 120. It may include a second separation membrane 142 positioned.
[74]
[75]
On the other hand, referring to FIGS. 1, 4 and 5, the first positive electrode tab 151 and the first negative electrode tab 161 are in a direction in which the positive electrode sheet 110 and the negative electrode sheet 120 face each other. It may be provided so as not to overlap each other. Here, a direction of the positive electrode sheet 110 and the negative electrode sheet 120 facing each other may be, for example, a lateral direction (S) of the winding central axis (C).
[76]
In addition, the first positive electrode tab 151 protrudes in one direction C1 based on a direction parallel to the winding central axis C, which is a central axis in which the electrode assembly 100 is wound, and the first negative tab 161 is It may protrude in the other direction C2 based on a direction parallel to the winding central axis C. Here, when referring to FIG. 1, for example, the first positive electrode tab 151 protrudes upward from the electrode assembly 100 to be connected to the cap assembly 12, and the first negative electrode tab 161 is The electrode assembly 100 may protrude downward and be connected to the inner bottom surface of the battery case 11.
[77]
In addition, ends of the first positive electrode tab 151 and the first negative electrode tab 161 may be positioned to be spaced apart from each other by a predetermined distance based on a direction parallel to the winding central axis C so as not to overlap with each other.
[78]
[79]
On the other hand, referring to FIGS. 1, 3 and 6, one side (110c, 120c) on both sides of the anode sheet 110 and the cathode sheet 120 is positioned toward the inner direction (S1) during winding, and the other side (110d) , 120d) may be located in the outer direction S2 on the winding side. In this case, the first positive electrode tab 151 may be located on the other surface 110d of the positive electrode sheet 110, and the first negative electrode tab 161 may be located on the one surface 120c of the negative electrode sheet 120.
[80]
And, the positive electrode sheet 110 and the negative electrode sheet 120, for example, one side portion (110a, 120a) is wound on both sides to be located in the outer corner of the winding, the other side (110b, 120b) may be located in the center of the winding. have. At this time, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound around the other side portions 110b and 120b. Here, the winding center may be a center region after the positive electrode sheet 110 and the negative electrode sheet 120 are wound, and the wound outer portion may be an outer region after the positive electrode sheet 110 and the negative electrode sheet 120 are wound. At this time, referring to the matters 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 have one side portion 110a and 120a wound around the other side portions 110b and 120b in a clockwise direction.
[81]
However, the present invention is not necessarily limited thereto, and as another example, in the positive electrode sheet 110 and the negative electrode sheet 120, one side portion 110a, 120a is wound on both sides to be positioned in the winding center, and the other side portion 110b, 120b) may be located on the outer periphery of the winding. In this case, the positive electrode sheet 110 and the negative electrode sheet 120 may be wound around one side portion 110a and 120a. In other words, it is the opposite of 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, a counterclockwise direction.
[82]
[83]
In addition, the first anode uncoated portion 113a and the second anode uncoated portion 113b are formed between both sides of the anode sheet 110, and the first anode uncoated portion 113a is one side of the anode sheet 110 It may be located on the (110a) side.
[84]
[85]
Meanwhile, referring to FIGS. 3 and 4, in the electrode assembly 100 according to the first embodiment of the present invention, an anode insulating tape 170 is further attached to the anode uncoated portion 113 to cover the anode tab 150. Then, the negative electrode insulating tape 180 may be further attached to the negative electrode uncoated portion 123 to cover the negative electrode tab 160. Here, a positive insulating tape 170 and a negative insulating tape 180 of insulating material are provided to cover the positive tab 150 and the negative tab 160, and are provided at the corners of the positive tab 150 and the negative tab 160 By this, the separator 140 can be prevented from being ruptured, and when the separator 140 is damaged, the positive electrode tab 150 directly contacts the negative electrode sheet 120 or the negative electrode tab 160 is in contact with the negative electrode sheet 110 through a damaged area It can prevent the occurrence of short circuit by direct contact with.
[86]
The positive electrode insulating tape 170 covers the first positive electrode insulating tape 171 and the second positive electrode tab 152 attached to the first positive electrode uncoated portion 113a to cover the first positive electrode tab 151. A second positive electrode insulating tape 182 attached to the uncoated portion 113b may be included.
[87]
The negative electrode insulating tape 180 includes a first negative electrode insulating tape 181 attached to the first negative electrode uncoated part 123a to cover the first negative electrode tab 161 and a second negative electrode tab 162 to cover the second negative electrode tab 162. Including a second negative electrode insulating tape 182 attached to the negative electrode uncoated portion 123b, and a third negative electrode insulating tape 183 attached to the third negative negative electrode uncoated portion 123c to cover the third negative electrode tab 163 can do. In addition, the negative electrode insulating tape 180 may further include a fourth negative electrode insulating tape 184 attached to a surface opposite to the surface on which the second negative electrode tab 162 is positioned in the second negative electrode uncoated portion 123b. That is, the second negative electrode uncoated portion 123b is formed on both sides of the negative electrode sheet 120, the second negative electrode tab 162 is positioned on one surface of the second negative electrode uncoated portion 123b, and the fourth negative electrode insulating tape ( The 184 may be located on the other surface of the second negative electrode uncoated portion 123b.
[88]
In addition, the positive insulating tape 170 and the negative insulating tape 180 may be formed of an electrical insulating material. At this time, the positive insulating tape 170 and the negative insulating tape 180 may not have pores through which lithium ions can move. Accordingly, the positive electrode insulating tape 170 and the negative electrode insulating tape 180 are made of a material resistant to physical damage, and may not be damaged by the edges of the positive electrode tab 150 and the negative electrode tab 160, and the positive electrode tab It is also possible to prevent damage to the portion of the separator 140 that faces the 150 and the negative electrode tab 160.
[89]
Meanwhile, the positive insulating tape 170 and the negative insulating tape 180 may include, for example, a substrate (not shown) and an adhesive layer (not shown) formed on one surface of the substrate.
[90]
[91]
Meanwhile, referring to FIGS. 3 and 6, the electrode assembly 100 according to the first exemplary embodiment of the present invention includes a positive electrode sheet 110 facing each other with a first negative electrode insulating tape 181 and a separator 140 interposed therebetween. A lithium ion precipitation prevention tape 190 may be further attached to the portion. Here, the lithium ion precipitation prevention tape 190 is provided, for example, on the other surface 110d of the positive electrode sheet 110, and is close to one side portion 110a of the positive electrode sheet 110 and one side portion 110a of the positive electrode sheet. It may be positioned on the surface of the positive electrode active material portion 112 stacked between the positioned first positive electrode uncoated portions 113a. In this case, the lithium ion precipitation prevention tape 190 and the first negative electrode uncoated portion 123a may face each other with the second separator 142 therebetween. In addition, the lithium ion precipitation prevention tape 190 may be formed of an electrical insulating material.
[92]
Accordingly, 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, the lithium ion precipitation prevention tape 190 is positioned so that lithium ions are It is not possible to exchange, but it can prevent lithium ions from accumulating and precipitation.
[93]
That is, by attaching the lithium ion precipitation prevention tape 190 to the surface of the positive electrode active material portion 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181, the positive electrode sheet 110 and the negative electrode sheet 120 ), lithium ions are exchanged between, and during charging and discharging, lithium ions accumulate and precipitate in a portion where lithium ions cannot be exchanged due to the first negative electrode insulating tape 181 can be prevented.
[94]
More specifically, the separator 140 is in the form of a thin film and is positioned between the positive electrode sheet 110 and the negative electrode sheet 120 to prevent direct contact between the positive electrode sheet 110 and the negative electrode sheet 120, and It is moved through the fine pores of the separation membrane 140, and charging and discharging are performed. Here, the first negative electrode insulating tape 181 is made of an insulating material in which fine pores are not formed so that lithium ions cannot be moved. In this case, lithium ions that are blocked by the first negative electrode insulating tape 181 and cannot be moved may be accumulated and deposited 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. Accordingly, the electrode assembly 100 according to the first embodiment of the present invention prevents the precipitation of lithium ions of an insulating material 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 By attaching the tape 190, lithium ions may be prevented from accumulating on the surface of the positive electrode active material part 112 facing the first negative electrode insulating tape 181.
[95]
Meanwhile, the lithium ion precipitation prevention tape 190 may be formed of, for example, polyimide (PI).
[96]
In addition, the lithium ion precipitation prevention tape 190 may include, for example, a substrate (not shown) and an adhesive layer (not shown) formed on one surface of the substrate.
[97]
[98]
Referring to FIG. 3, the electrode assembly 100 according to the first embodiment of the present invention configured as described above includes the first negative tab 161 so that the number of the negative electrode tabs 160 is greater than the number of the positive electrode tabs 150. In addition, the resistance can be reduced.
[99]
At this time, a 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 a first positive electrode uncoated portion in which the first positive electrode tab 151 is located. By forming to correspond to (113a), the additional loss of battery capacity can be prevented or significantly reduced. That is, when the first negative uncoated portion 123a is additionally formed, if an additional positive uncoated portion is formed on the positive electrode sheet 110 to correspond thereto, the positive electrode active material portion 122 is reduced to reduce battery capacity, so that the first negative uncoated portion ( 123a) is matched with the first positive electrode uncoated portion 113a in which the first positive electrode tab 151 is positioned so as not to form an additional positive electrode uncoated portion, so that a decrease in battery capacity may be significantly reduced or prevented.
[100]
[101]
Hereinafter, an electrode assembly according to a second embodiment of the present invention will be described.
[102]
7 is a front view showing an unfolded state before the electrode assembly according to the second embodiment of the present invention is wound.
[103]
Referring to FIG. 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 part 212 and a positive electrode uncoated part 213, and a positive electrode uncoated part 213. A negative electrode sheet 220 including a positive electrode tab 250 provided in the negative electrode active material part 222 and a negative negative electrode uncoated part 223, a negative electrode tab 260 provided in the negative electrode uncoated part 223, and a positive electrode And a separator 140 provided between the sheet 210 and the negative electrode sheet 220.
[104]
The electrode assembly 200 according to the second embodiment of the present invention has a difference in the positions of the anode uncoated portion 213 and the cathode uncoated portion 223 in the electrode assembly 100 according to the first embodiment. In the example, the content overlapping with the above-described embodiment will be briefly described, and the differences will be mainly described.
[105]
In more detail, in more detail, the positive electrode sheet 210 includes a positive electrode active material part 212, which is a region in which a positive electrode active material is stacked on the positive electrode current collector 211, and a positive electrode uncoated part 213, which is a region in which the positive electrode active material is not laminated. can do.
[106]
The anode uncoated portion 213 is formed of two portions spaced apart from each other, and may include a first anode uncoated portion 213a and a second anode uncoated portion 213b. Here, the anode uncoated portion 213 may be formed on one or more of both surfaces of the anode sheet 210.
[107]
The first anode uncoated portion 213a and the second anode uncoated portion 213b may be positioned between both side portions in the longitudinal direction of the anode sheet 210.
[108]
Here, the first anode uncoated portion 213a is positioned close to the other side portion 210b of the anode sheet 210, and the second anode uncoated portion 213b is one side portion 210a of the anode sheet 210 Can be located close to.
[109]
In addition, when the positive electrode sheet 210 is wound, the first positive electrode uncoated portion 213a may be positioned on the outer side of the winding, and the second positive electrode uncoated portion 213b may be positioned at the winding center side. However, the present invention is not necessarily limited thereto, for example, when the positive electrode sheet 210 is wound, the first positive electrode uncoated portion 213a is located at the center of the winding, and the second positive electrode uncoated portion 213b is It may be located on the outer side of the winding.
[110]
The positive electrode tab 250 is provided on the positive electrode uncoated portion 213 of the positive electrode sheet 210. Here, the positive electrode tab 250 may have one end attached and fixed to the positive electrode uncoated portion 213, and the other end may protrude from the positive electrode sheet 210.
[111]
In addition, the anode tab 250 may include a first anode tab 251 provided in the first anode uncoated portion 213a and a second anode tab 252 provided in the second anode uncoated portion 213b. .
[112]
The negative electrode sheet 220 may include a negative electrode active material part 222, which is a region in which a negative active material is stacked on the negative current collector 221, and a negative electrode uncoated part 223, which is a region in which the negative active material is not laminated.
[113]
The negative electrode uncoated portion 223 includes a first negative electrode uncoated portion 223a formed between both side portions in the longitudinal direction of the negative electrode sheet 220, a second negative electrode uncoated portion 223b formed on both sides of the negative electrode sheet 220, and A third negative electrode uncoated portion 223c may be included. Here, the negative electrode uncoated portion 223 may be formed on one or more of both surfaces of the negative electrode sheet 220.
[114]
Meanwhile, the second anode uncoated portion 213b and the first cathode uncoated portion 223a may be formed at positions corresponding to each other.
[115]
The negative electrode tab 260 is provided on the negative electrode uncoated portion 223. Here, the negative electrode tab 260 may have one end attached and fixed to the negative electrode uncoated portion 223, and the other end may protrude from the negative electrode sheet 220.
[116]
In addition, the negative electrode tab 260 includes a first negative electrode tab 261 provided in the first negative electrode uncoated part 223a, a second negative electrode tab 262 provided in the second negative negative electrode uncoated part 223b, and a third A third negative electrode tab 263 provided on the negative electrode uncoated part 223c may be included.
[117]
In the electrode assembly 200 according to the second embodiment of the present invention, a positive insulating tape 270 is further attached to the positive electrode uncoated part 213 to cover the positive electrode tab 250, and the negative electrode is applied to cover the negative electrode tab 260. A negative electrode insulating tape 280 may be further attached to the uncoated portion 223.
[118]
The positive electrode insulating tape 270 is a second positive electrode to cover the first positive electrode insulating tape 271 and the second positive electrode tab 252 attached to the first positive electrode uncoated portion 213a to cover the first positive electrode tab 251. A second positive electrode insulating tape 272 attached to the uncoated portion 213b may be included.
[119]
The negative electrode insulating tape 280 is a second negative electrode insulating tape 281 attached to the first negative electrode uncoated portion 223a to cover the first negative electrode tab 261 and the second negative electrode tab 262. Including a second negative electrode insulating tape 282 attached to the negative electrode uncoated portion 223b, and a third negative electrode insulating tape 283 attached to the third negative negative electrode uncoated portion 223c to cover the third negative electrode tab 263 can do. In addition, the negative electrode insulating tape 280 may further include a fourth negative electrode insulating tape 284 attached to a surface opposite to the surface on which the second negative electrode tab 162 is positioned in the second negative electrode uncoated portion 123b. That is, the second negative electrode uncoated portion 223b is formed on both sides of the negative electrode sheet 220, the second negative electrode tab 262 is positioned on one surface of the second negative electrode uncoated portion 223b, and the fourth negative electrode insulating tape ( The 284 may be located on the other surface of the second negative electrode uncoated portion 223b.
[120]
[121]
Hereinafter, an electrode assembly according to a third embodiment of the present invention will be described with reference to FIGS. 8 and 9.
[122]
8 is a front view showing an unfolded state before the electrode assembly according to the third embodiment of the present invention is wound, and FIG. 9 is a front view showing the main part of the present invention in a state where the electrode assembly according to the third embodiment of the present invention is wound It is a partial front view.
[123]
8 and 9, the electrode assembly 300 according to the third embodiment of the present invention includes a positive electrode sheet 310 including a positive electrode active material part 312 and a positive electrode uncoated part 313, and a positive electrode uncoated part. A negative electrode sheet 320 including a positive electrode tab 350 provided in 313, a negative electrode active material part 322 and a negative electrode uncoated part 323, and a negative electrode tab 360 provided in the negative electrode uncoated part 323 , And a separator 140 provided between the positive electrode sheet 310 and the negative electrode sheet 320.
[124]
The electrode assembly 300 according to the third embodiment of the present invention has a difference in its winding shape when compared to the electrode assembly according to the first embodiment and the electrode assembly according to the second embodiment. Contents overlapping with the examples will be omitted or briefly described, and the differences will be mainly described.
[125]
In more detail, the positive electrode sheet 310 may include a positive electrode active material portion 312 that is a region in which a positive electrode active material is stacked on the positive electrode current collector 311 and a positive electrode uncoated portion 313 that is a region in which the positive electrode active material is not laminated. .
[126]
The anode uncoated portion 313 is formed of two portions spaced apart from each other, and may include a first anode uncoated portion 313a and a second anode uncoated portion 313b. Here, the anode uncoated portion 313 may be formed on one or more of both sides of the anode sheet 310.
[127]
The first anode uncoated portion 313a and the second anode uncoated portion 313b may be positioned between both side portions in the longitudinal direction of the anode sheet 310.
[128]
Here, the first anode uncoated portion 313a is positioned close to, for example, one side 310a of the anode sheet 310, and the second anode uncoated portion 313b is the other side 310b of the anode sheet 310 And can be located close to.
[129]
In addition, when the positive electrode sheet 310 is wound, the first positive electrode uncoated portion 313a may be positioned at the center of the winding, and the second positive electrode uncoated portion 313b may be positioned at the winding outer portion. However, the present invention is not necessarily limited thereto, for example, when the positive electrode sheet 310 is wound, the first positive electrode uncoated portion 313a is positioned on the winding outer portion side, and the second positive electrode uncoated portion 313b May be located on the winding center side.
[130]
The positive electrode tab 350 is provided on the positive electrode uncoated portion 313 of the positive electrode sheet 310. Here, the positive electrode tab 350 may have one end attached and fixed to the positive electrode uncoated portion 313, and the other end may protrude from the positive electrode sheet 310.
[131]
In addition, the anode tab 350 may include a first anode tab 351 provided in the first anode uncoated portion 313a and a second anode tab 352 provided in the second anode uncoated portion 313b. . Here, the first positive electrode tab 351 and the second positive electrode tab 352 may be positioned on the other surface 310d of the positive electrode sheet 310, for example.
[132]
Here, the first positive electrode tab 351 and the second positive electrode tab 352 are illustrated as being positioned on the other surface 310d of the positive electrode sheet 310 in FIG. 9 as an example, but the present invention is necessarily limited thereto. In addition, 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 positioned on one surface 310c of the positive electrode sheet 310.
[133]
The negative electrode sheet 320 may include a negative electrode active material portion 322 that is a region in which a negative electrode active material is stacked on the negative electrode current collector 321 and a negative electrode uncoated portion 323 that is a region in which the negative electrode active material is not stacked.
[134]
The negative electrode uncoated portion 323 includes a first negative electrode uncoated portion 323a formed between both side portions in the longitudinal direction of the negative electrode sheet 320, a second negative electrode uncoated portion 323b formed on both sides of the negative electrode sheet 320, and A third negative electrode uncoated portion 323c may be included. Here, the negative electrode uncoated portion 323 may be formed on one or more of both surfaces of the negative electrode sheet 320.
[135]
Meanwhile, the first anode uncoated portion 313a and the first cathode uncoated portion 323a may be formed at positions corresponding to each other.
[136]
The negative electrode tab 360 is provided on the negative electrode uncoated portion 323. Here, the negative electrode tab 360 may have one end attached and fixed to the negative electrode uncoated portion 323, and the other end may protrude from the negative electrode sheet 320.
[137]
In addition, the negative electrode tab 360 includes a first negative electrode tab 361 provided in the first negative electrode uncoated part 323a, a second negative electrode tab 362 provided in the second negative electrode uncoated part 323b, and a third negative electrode tab 360. A third negative electrode tab 363 provided in the negative electrode uncoated part 323c may be included. Here, the first negative electrode tab 361 and the second negative electrode tab 362 are, for example, located on one surface 320c of the negative electrode sheet 320 in FIG. 8, and the third negative electrode tab 363 is the negative electrode sheet 320. Although shown to be located on the other surface (320d) of, the present invention is not necessarily limited thereto, the first negative electrode tab 361, the second negative electrode tab 362, and the third negative electrode tab 363, respectively It may be formed on one surface 320c or the other surface 320d of the sheet 320. At this time, as another example, the first negative electrode tab 361 and the second negative electrode tab 362 are located on the other surface 320d of the negative electrode sheet 320, and the third negative electrode tab 363 is one surface of the negative electrode sheet 320 ( 320c).
[138]
[139]
On the other hand, on both sides of the positive electrode sheet 310 and the negative electrode sheet 320, one surface 310c and 320c may be located toward the outside during winding, and the other surfaces 310d and 320d may be located toward the inside of the winding side. In this case, the first positive electrode tab 351 may be located on the other surface 310d of the positive electrode sheet 310, and the first negative electrode tab 361 may be located on the one surface 320c of the negative electrode sheet 320.
[140]
And, the positive electrode sheet 310 and the negative electrode sheet 320, for example, the other side portions 310b and 320b are wound on both sides and located in the center of the winding, and one side portions 310a and 320a are wound and located in the outer corner of the winding. Can be. At this time, the positive electrode sheet 310 and the negative electrode sheet 320 are wound from the other side portions 310b and 320b to be wound in the direction of one side portions 310a and 320a, and may be wound in a clockwise direction. In this case, the winding direction R of the positive electrode sheet 110 and the negative electrode sheet 120 may be, for example, a clockwise direction.
[141]
However, the present invention is not necessarily limited thereto, and as another example, the positive electrode sheet 310 and the negative electrode sheet 320 are located in the center of the winding by winding the other side portions 310b and 320b from both sides, and one side portion 310a, 320a) may be located on the outer periphery of the winding. In this case, the positive electrode sheet 310 and the negative electrode sheet 320 may be wound around the other side portions 310b and 320b. In other words, it is the opposite of 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, a counterclockwise direction.
[142]
[143]
In the electrode assembly 300 according to the third embodiment of the present invention, a positive insulating tape 370 is further attached to the positive electrode uncoated portion 313 to cover the positive electrode tab 350, and a negative electrode is applied to cover the negative electrode tab 360. A negative electrode insulating tape 380 may be further attached to the uncoated portion 323.
[144]
The positive electrode insulating tape 370 is a second positive electrode to cover the first positive electrode insulating tape 371 and the second positive electrode tab 352 attached to the first positive electrode uncoated portion 313a to cover the first positive electrode tab 351. A second positive electrode insulating tape 372 attached to the uncoated portion 313b may be included.
[145]
The negative electrode insulating tape 380 includes a first negative electrode insulating tape 381 attached to the first negative electrode uncoated portion 323a to cover the first negative electrode tab 361 and a second negative electrode tab 362. Including a second negative electrode insulating tape 382 attached to the negative electrode uncoated portion 323b, and a third negative electrode insulating tape 383 attached to the third negative negative electrode uncoated portion 323c to cover the third negative electrode tab 363 can do. In addition, the negative electrode insulating tape 380 may further include a fourth negative electrode insulating tape 384 attached to a surface opposite to the surface on which the second negative electrode tab 362 is positioned in the second negative electrode uncoated portion 323b. That is, the second negative electrode uncoated portion 323b is formed on both sides of the negative electrode sheet 320, the second negative electrode tab 362 is positioned on one surface of the second negative electrode uncoated portion 323b, and the fourth negative electrode insulating tape ( 384 may be located on the other surface of the second negative electrode uncoated portion 323b.
[146]
[147]
Meanwhile, in the electrode assembly 300 according to the third embodiment of the present invention, a lithium ion precipitation prevention tape 390 is provided on a portion of the positive electrode sheet 310 that faces the first negative electrode insulating tape 381 and the separator 140 therebetween. ) May be attached.
[148]
[149]
Hereinafter, a secondary battery including an electrode assembly according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6.
[150]
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 accommodating 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 on the positive electrode uncoated portion 113, and a negative electrode active material portion. (122) and the negative electrode sheet 120 including the negative electrode uncoated portion 123, the negative electrode tab 160 provided in the negative electrode uncoated portion 123, and provided between the positive electrode sheet 110 and the negative electrode sheet 120 It includes the separated membrane 140.
[151]
The secondary battery 10 according to the embodiment of the present invention relates to a secondary battery 10 including the electrode assembly according to the first embodiment to the electrode assembly according to the third embodiment. Contents overlapping with should be briefly described, and the differences should be mainly described.
[152]
[153]
In more detail, referring to FIG. 1, in the secondary battery 10 according to the embodiment of the present invention, the battery case 11 may have a receiving portion 11a for accommodating the electrolyte and the electrode assembly 100 therein. . In this case, the battery case 11 may be opened in a form in which the receiving portion 11a is opened to one side, and a cap assembly 12 may be further provided to cover the opened side of the battery case 11. Here, the battery case 11 may be formed in an oval or cylindrical shape, for example.
[154]
In addition, the electrode assembly 100 is a power generating device capable of charging and discharging, and the electrode 130 and the separator 140 are assembled to form a structure in which the electrode 130 and the separator 140 are alternately stacked. Here, the electrode assembly 100 is an electrode assembly 100 for a lithium ion secondary battery, and may have a wound shape.
[155]
The electrode 130 may include a positive electrode sheet 110 and a negative electrode sheet 120. In addition, the separator 140 may separate the positive electrode sheet 110 and the negative electrode sheet 120 to be electrically insulated.
[156]
1 to 4, the positive electrode sheet 110 includes a positive electrode active material part 112, which is a region formed by stacking a positive electrode active material on the positive electrode current collector 111, and a positive electrode uncoated region, which is a region in which the positive electrode active material is not laminated. (113) may be included. Here, the anode uncoated portion 113 may be formed of two portions spaced apart from each other in the anode sheet 110, and may include a first anode uncoated portion 113a and a second anode uncoated portion 113b.
[157]
The positive electrode tab 150 is provided on the positive electrode uncoated portion 113 of the positive electrode sheet 110. Here, the positive electrode tab 150 may have one end 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 of the cap assembly 12 or the battery case 11.
[158]
In addition, the anode tab 150 may include a first anode tab 151 provided in the first anode uncoated portion 113a and a second anode tab 152 provided in the second anode uncoated portion 113b. .
[159]
The negative electrode sheet 120 may include a negative electrode active material portion 122 that is a region formed by stacking a negative electrode active material on the negative electrode current collector 121 and a negative electrode uncoated portion 123 that is a region in which the negative electrode active material is not stacked. Here, the negative electrode uncoated portion 123 includes a first negative electrode uncoated portion 123a formed between both sides of the negative electrode sheet 120, and a second negative electrode uncoated portion 123b formed on both sides of the negative electrode sheet 120, and the second negative electrode uncoated portion 123 It may include a negative electrode uncoated portion (123c). In this case, the first negative uncoated portion 123a may be formed on one side 120a of the negative electrode sheet 120, and the second negative uncoated portion 123b may be formed on the other side 120b of the negative electrode sheet 120. have.
[160]
The negative electrode tab 160 is provided on the negative electrode uncoated part 123. Here, the negative electrode tab 160 may have one end attached and fixed to the negative electrode uncoated part 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 of the cap assembly 12 or the battery case 11.
[161]
[162]
In addition, the negative electrode tab 160 includes a first negative electrode tab 161 provided in the first negative electrode uncoated part 123a, a second negative electrode tab 162 provided in the second negative negative electrode uncoated part 123b, and a third A third negative electrode tab 163 provided in the negative electrode uncoated part 123c may be included.
[163]
In this case, the first anode uncoated portion 113a and the first cathode uncoated portion 123a may be formed at positions corresponding to each other.
[164]
[165]
And, referring to FIG. 5, the first positive electrode tab 151 and the first negative electrode tab 161 may be provided so that the positive electrode sheet 110 and the negative electrode sheet 120 do not overlap each other in a direction facing each other. .
[166]
[167]
Meanwhile, referring to FIGS. 3 and 6, in the secondary battery 10 according to the embodiment of the present invention, the electrode assembly 100 is formed on the first negative electrode uncoated portion 123a to cover the first negative electrode tab 161. 1 A negative electrode insulating tape 181 may be further attached.
[168]
[169]
In addition, in the secondary battery 10 according to the embodiment of the present invention, the electrode assembly 100 is further attached with a lithium ion precipitation prevention tape 190 to the portion of the positive electrode sheet 110 that faces the first negative electrode uncoated portion 123a. Can be.
[170]
Accordingly, in the portion of the positive electrode sheet 110 that faces the first negative electrode uncoated portion 123a to which the first negative insulating tape 181 is attached during charging and discharging, lithium ions cannot be exchanged, but lithium ions are prevented from accumulating and precipitation. can do.
[171]
That is, by attaching the lithium ion precipitation prevention tape 190 to the surface of the positive electrode active material portion 112 of the positive electrode sheet 110 facing the first negative electrode insulating tape 181, the positive electrode sheet 110 and the negative electrode sheet 120 ), lithium ions are exchanged between, and during charging and discharging, lithium ions accumulate and precipitate in a portion where lithium ions cannot be exchanged due to the first negative electrode insulating tape 181 can be prevented.
[172]
[173]
10 is a perspective view showing an unfolded state before a positive electrode plate and a negative electrode plate are wound in the electrode assembly according to the fourth embodiment of the present invention.
[174]
Hereinafter, an electrode assembly according to a fourth embodiment of the present invention will be described with reference to FIG. 10.
[175]
Referring to FIG. 10, an electrode assembly 1100 according to a 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, and a positive electrode uncoated portion 1113. A negative electrode plate 1120 including a positive electrode tab 1150 provided in, a negative electrode active material part 1122 and a negative electrode uncoated part 1123, a negative electrode tab 1160 provided in the negative electrode uncoated part 1123, and a positive electrode plate ( 1110 and a separator 1140 provided between the negative electrode plate 1120.
[176]
The electrode assembly 1100 is a power generating device capable of charging and discharging, and forms a structure in which the electrodes 1130 and the separators 140 are alternately stacked. Here, the electrode assembly 1100 is an electrode assembly 1100 for a lithium ion secondary battery, and may have a wound shape.
[177]
The electrode 1130 may include a positive electrode plate 1110 and a negative electrode plate 1120. In addition, the separator 1140 may separate the positive electrode plate 1110 and the negative electrode plate 1120 to be electrically insulated.
[178]
Further, the positive electrode plate 1110 and the negative electrode plate 1120 are alternately stacked and wound together with the separator 1140, but may be formed in a roll shape. Here, the electrode assembly 1100 may be wound in a circular or elliptical shape, for example, and formed in a jelly roll shape.
[179]
[180]
The positive electrode plate 1110 includes 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 an area in which the positive electrode active material is not stacked. ) Can be included.
[181]
The positive electrode current collector 1111 may be made of, for example, a foil made of aluminum (Al).
[182]
The positive active material part 1112 may be formed to include a positive active material stacked on the first surface M12 of the positive current collector 1111. In addition, the positive active material part 1112 may be formed to further include a positive active material stacked on the second surface of the positive current collector 1111. In addition, the positive active material part 1112 may be formed to further include a binder and a conductive material in addition to the positive active material.
[183]
The anode uncoated portion 1113 may include, for example, two portions spaced apart from each other, and may include a first anode uncoated portion 1113a and a second anode uncoated portion 1113b. Here, the first anode uncoated portion 1113a may be positioned between both ends of the anode plate 1110.
[184]
On the other hand, the anode uncoated portion 1113 may be formed of three portions spaced apart from each other as another example, and may include a first anode uncoated portion 1113a, a second anode uncoated portion 1113b, and a third anode uncoated portion 1113c. have. In this case, the first anode uncoated portion 1113a may be positioned between both ends of the anode plate 1110.
[185]
[186]
The positive electrode tab 1150 may be provided on the positive electrode uncoated portion 1113 of the positive electrode plate 1110. In addition, the anode tab 1150 may include a first anode tab 1151 provided with the first anode uncoated portion 1113a. Here, the first positive electrode tab 1151 may have one end 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.
[187]
[188]
The negative electrode plate 1210 includes a negative electrode current collector 1121, a negative electrode active material part 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 part 1123, which is a region in which the negative active material is not stacked. ) Can be included.
[189]
The negative electrode current collector 1121 may be made of a foil made of, for example, copper (Cu) or nickel (Ni).
[190]
The negative active material part 1122 may be formed to include a negative active material stacked on the first surface M21 of the negative 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. 6, for convenience of explanation, the first surface M21 of the negative electrode current collector 1122 is shown to face the same direction as the first surface M12 of the positive electrode current collector 1111, but substantially the negative electrode current collector The first surface M21 of 1121 denotes a surface facing the first surface M12 of the positive electrode current collector 1111. In addition, the negative active material part 1122 may be formed to further include a negative active material stacked on the second surface of the negative current collector 1121. In addition, the negative active material part 1122 may be formed to further include a binder and a conductive material in addition to the negative active material.
[191]
The negative electrode uncoated portion 1123 includes a first negative uncoated portion 1123a formed between both ends of the negative electrode plate 1120, a second negative uncoated portion 1123b and a third negative uncoated portion 1123c formed at both ends of the negative electrode plate 1120. ) Can be included.
[192]
In addition, the first anode uncoated portion 1113a and the first cathode uncoated portion 1123a may be formed at positions corresponding to each other.
[193]
[194]
The negative electrode tab 1160 is provided on the negative electrode uncoated portion 1123. Here, the negative electrode tab 1160 may have one end 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 includes a first negative electrode tab 1161 provided in the first negative electrode uncoated part 1123a, a second negative electrode tab 1152 provided in the second negative negative electrode uncoated part 1123b, and a third negative electrode tab 1160. A third negative electrode tab 1153 provided in the negative electrode uncoated part 1123c may be included.
[195]
[196]
The separator 1140 is made of an insulating material and is alternately stacked with the positive electrode plate 1110 and the negative electrode plate 1120. Here, the separator 1140 may be positioned between the positive electrode plate 1110 and the negative electrode plate 1120 and on an outer surface of the positive electrode plate 1110 or the negative electrode plate 1120.
[197]
[198]
Meanwhile, the first positive electrode tab 1151 and the first negative electrode tab 1161 may be provided so as not to overlap each other with respect to a direction in which the positive electrode plate 1110 and the negative electrode plate 1120 face each other. Here, a 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 central axis of the winding. In addition, ends of the first positive electrode tab 1151 and the first negative electrode tab 1161 may be positioned to be spaced apart from each other by a predetermined distance based on a direction parallel to the winding central axis so as not to overlap with each other.
[199]
[200]
Meanwhile, in the electrode assembly 1100 according to the fourth embodiment of the present invention, a positive insulating tape is further attached to the positive electrode uncoated portion 1113 to cover the positive electrode tab 1150, and the negative electrode uncoated to cover the negative electrode tab 1160. A negative insulating tape may be further attached to the part 1123. 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).
[201]
The positive electrode insulating tape may include a first positive electrode insulating tape attached to the first positive electrode uncoated portion 1113a to cover the first positive electrode tab 1151.
[202]
The negative electrode insulating tape includes a first negative electrode insulating tape attached to the first negative electrode uncoated portion 1213a to cover the first negative electrode tab 161 and a second negative negative electrode uncoated portion 1123b to cover the second negative electrode tab 1162 A second negative electrode insulating tape attached to and a third negative electrode insulating tape attached to the third negative electrode uncoated portion 1123c to cover the third negative electrode tab 1163.
[203]
In addition, the positive insulating tape and the negative insulating tape may be formed of an electrical insulating material.
[204]
[205]
On the other hand, in the electrode assembly 1100 according to the fourth embodiment of the present invention, a lithium ion precipitation prevention tape including an insulating material is formed on a portion of the positive electrode plate 1110 that faces the first negative electrode insulating tape and the separator 1140 therebetween. More can be attached. Here, the lithium ion precipitation prevention tape may be attached in the same form as the lithium ion precipitation 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 precipitation prevention tape may be positioned on the surface of the positive electrode active material portion 1112 of the positive electrode plate 1110, for example. Accordingly, in the portion of the positive electrode plate 1110 facing the first negative electrode uncoated portion 1123a to which the first negative insulating tape is attached during charging and discharging, the lithium ion precipitation prevention tape 1190 is positioned so that lithium ions cannot be exchanged. Ions can be prevented from accumulating and precipitation.
[206]
[207]

[208]
1-1 electrode assembly manufacturing
[209]
An anode uncoated portion is formed on two portions of the positive electrode sheet spaced apart from each other to provide a positive electrode tab, and a negative electrode uncoated portion is formed in three portions of the negative electrode sheet spaced apart from each other to provide a negative electrode tab. An electrode assembly provided with a tab was manufactured.
[210]
At this time, in the anode uncoated portion provided in two portions of the anode sheet, the first anode uncoated portion and the first anode uncoated portion formed between both sides of the cathode sheet were formed at positions corresponding to each other.
[211]
[212]
1-2 Secondary battery manufacturing
[213]
A secondary battery was manufactured by accommodating the prepared electrode assembly together with an electrolyte in a battery case.
[214]
[215]

[216]
An anode uncoated portion was formed on two portions of the positive electrode sheet spaced apart from each other to provide a positive electrode tab, and a negative electrode uncoated portion was formed on two portions of the negative electrode sheet spaced apart from each other to provide a negative electrode tab, respectively, two positive electrode tabs and two negative electrodes. A secondary battery was manufactured in the same manner as in Preparation Example except that an electrode assembly provided with a tab was manufactured. Here, in the comparative example, the negative electrode uncoated portion was formed in two portions of the negative electrode sheet, so that the first negative electrode uncoated portion formed between both side portions of the negative electrode sheet of Preparation Example was not formed.
[217]
[218]

[219]
The effect of improving resistance was measured by applying electricity to the secondary battery.
[220]
As a result of measuring AC (alternating current; alternating current) resistance, it was observed that the resistance value measured in Preparation Example decreased by about 20% compared to the resistance value measured in Comparative Example.
[221]
As a result, it can be seen that the resistance is remarkably improved in the manufacturing example.
[222]
[223]
Although the present invention has been described in detail through specific examples, this is for explaining the present invention in detail, and the electrode assembly according to the present invention and a secondary battery including the same are not limited thereto. It will be said that various implementations are possible by those of ordinary skill in the art within the technical idea of ​​the present invention.
[224]
In addition, the specific scope of protection of the invention will be made clear by the appended claims.
Claims
[Claim 1]
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 in which the positive electrode active material is not laminated; An anode tab provided on the anode uncoated portion; A negative electrode sheet including a negative electrode active material part formed by stacking a negative electrode active material on the negative electrode current collector and a negative negative electrode uncoated part indicating a region in which the negative active material is not stacked; A negative electrode tab provided on the negative electrode uncoated portion; And a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein the positive electrode uncoated portion includes a first positive electrode uncoated portion and a second positive electrode uncoated portion formed at two portions spaced apart from each other in the positive electrode sheet, and the negative electrode uncoated portion A first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, a second negative electrode uncoated portion and a third negative negative electrode uncoated portion formed on both sides of the negative electrode sheet, and the first positive electrode uncoated portion and the first negative electrode uncoated portion An electrode assembly formed at positions corresponding to each other.
[Claim 2]
The method according to claim 1, wherein the positive electrode tab comprises a first positive electrode tab provided in the first positive electrode uncoated part and a second positive electrode tab provided in the second positive positive electrode uncoated part, wherein the negative electrode tab comprises the first negative uncoated part An electrode assembly comprising: a first negative electrode tab provided in, a second negative electrode tab provided in the second negative electrode non-coating part, and a third negative electrode tab provided in the third negative negative electrode non-coating part.
[Claim 3]
The method according to claim 2, wherein the electrode assembly is an electrode assembly for a lithium ion secondary battery, wherein the positive electrode sheet, the separator, and the negative electrode sheet are alternately stacked and wound, and the first negative electrode uncoated portion is covered with the first negative electrode tab. A first negative electrode insulating tape is further attached to the electrode assembly, and a lithium ion precipitation preventing tape is further attached to the positive electrode sheet portion facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging.
[Claim 4]
The electrode assembly of claim 3, wherein the separator comprises an insulating material in which pores through which the lithium ions are moved, and the first negative electrode insulating tape and the lithium ion precipitation prevention tape include an insulating material.
[Claim 5]
The method according to claim 3, wherein the positive electrode sheet and the negative electrode sheet have one side of the positive electrode sheet wound in a clockwise direction from both sides and positioned at the outer edge of the winding, the other side is located in the center of the winding, and the first anode uncoated portion and the second anode An electrode assembly wherein the uncoated portion is formed between both side portions of the positive electrode sheet, and the first anode uncoated portion is positioned at one side of the positive electrode sheet.
[Claim 6]
The electrode assembly of claim 5, wherein one side of the positive electrode sheet and the negative electrode sheet is positioned in an inner direction during winding, and the other surface is positioned in an outer direction toward the winding side.
[Claim 7]
The method according to claim 3, wherein the positive electrode sheet and the negative electrode sheet are wound from the other side of both sides and are wound in a clockwise direction in a direction of one side, the other side is located in the winding center, and one side is located in the winding outer shell And the first anode uncoated portion and the second anode uncoated portion is formed between both side portions of the anode sheet, and the first anode uncoated portion is positioned at one side of the anode sheet.
[Claim 8]
The electrode assembly of claim 7, wherein on both surfaces of the positive electrode sheet and the negative electrode sheet, one surface is positioned toward the outside during winding, and the other surface is located toward the inside of the winding side.
[Claim 9]
The method according to claim 6 or 8, wherein the lithium ion precipitation prevention tape is provided on the other surface of the positive electrode sheet, and is laminated between one side of the positive electrode sheet and the first positive electrode uncoated portion located close to one side of the positive electrode sheet. An electrode assembly positioned on the surface of the positive electrode active material part.
[Claim 10]
The method according to claim 9, wherein the separator is a first separator positioned between one surface of the positive electrode sheet and the other surface of the negative electrode sheet; And a second separator positioned on one surface of the negative electrode sheet, wherein the first negative electrode uncoated part and the lithium ion precipitation prevention tape face each other with the second separator interposed therebetween.
[Claim 11]
The electrode assembly according to any one of claims 2 to 8, wherein the first positive electrode tab and the first negative electrode tab are provided so that the positive electrode sheet and the negative electrode sheet do not overlap with each other in a direction facing each other.
[Claim 12]
The method according to claim 11, wherein the first positive electrode tab protrudes in one direction based on a direction parallel to the winding central axis, the first negative tab protrudes in the other direction based on a direction parallel to the winding central axis, and the first An electrode assembly positioned to be spaced apart from each other by a predetermined distance based on a direction parallel to the winding central axis so that ends of the positive electrode tab and the first negative electrode tab do not overlap each other.
[Claim 13]
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 in which the positive electrode active material is not laminated; An anode tab provided on the anode uncoated portion; A negative electrode sheet including a negative electrode active material part formed by stacking a negative electrode active material on the negative electrode current collector and a negative negative electrode uncoated part indicating a region in which the negative active material is not stacked; A negative electrode tab provided on the negative electrode uncoated portion; And a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein the positive electrode uncoated portion includes a first positive electrode uncoated portion and a second positive electrode uncoated portion formed at two portions spaced apart from each other in the positive electrode sheet, and the negative electrode uncoated portion A first negative electrode uncoated portion formed between both side portions of the negative electrode sheet, a second negative electrode uncoated portion and a third negative electrode uncoated portion formed on both sides of the negative electrode sheet, and the second positive electrode uncoated portion and the first negative electrode uncoated portion An electrode assembly formed at positions corresponding to each other.
[Claim 14]
The method according to claim 13, wherein the positive electrode sheet and the negative electrode sheet are located at an outer portion of the winding by winding one side from both sides in a clockwise direction, the other side is located in the center of the winding, and the first anode uncoated portion and the second anode An electrode assembly wherein the uncoated portion is formed between both side portions of the positive electrode sheet, and the second anode uncoated portion is positioned on the other side of the positive electrode sheet.
[Claim 15]
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 in which the positive electrode active material is not laminated; An anode tab provided on the anode uncoated portion; A negative electrode sheet including a negative electrode active material part formed by stacking a negative electrode active material on the negative electrode current collector and a negative negative electrode uncoated part indicating a region in which the negative active material is not stacked; A negative electrode tab provided on the negative electrode uncoated portion; And a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein 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 negative electrode uncoated portion formed on the negative electrode sheet, , The first anode uncoated portion and the first cathode uncoated portion are formed at positions corresponding to each other, the anode tab includes a first anode tab provided on the first anode uncoated portion, and the cathode tab is the first An electrode assembly comprising a first negative electrode tab provided on a negative electrode uncoated portion, wherein the first positive electrode tab and the first negative electrode tab are provided so that the positive electrode sheet and the negative electrode sheet do not overlap with each other in a direction facing each other.
[Claim 16]
The method of claim 15, wherein the first positive electrode tab protrudes in one direction based on a direction parallel to the winding central axis, and the first negative tab protrudes in the other direction based on a direction parallel to the winding central axis, and the first An electrode assembly positioned to be spaced apart from each other by a predetermined distance based on a direction parallel to the winding central axis so that ends of the positive electrode tab and the first negative electrode tab do not overlap each other.
[Claim 17]
A positive electrode comprising an electrode assembly and a battery case accommodating the electrode assembly, wherein the electrode assembly includes a positive electrode current collector, a positive electrode active material stacked on the positive electrode current collector, and a positive electrode uncoated portion which is a region in which the positive electrode active material is not stacked. Sheet; An anode tab provided on the anode uncoated portion; A negative electrode sheet including a negative electrode current collector, a negative electrode active material stacked on the negative electrode current collector, and a negative electrode uncoated portion that is a region in which the negative electrode active material is not laminated; A negative electrode tab provided on the negative electrode sheet; And a separator insulating between the positive electrode sheet and the negative electrode sheet, wherein the positive electrode uncoated part includes a first positive uncoated part and a second positive uncoated part formed in two portions of the positive electrode sheet, and the negative uncoated part comprises the negative electrode sheet A first negative electrode uncoated portion formed between both sides of the negative electrode sheet, and a second negative electrode uncoated portion and a third negative negative electrode uncoated portion formed on both sides of the negative electrode sheet, and the first positive electrode uncoated portion and the first negative electrode uncoated portion correspond Secondary battery formed at the location.
[Claim 18]
An electrode assembly, comprising: a positive electrode plate including a positive electrode active material portion coated with a positive electrode active material on a first surface of a positive electrode current collector and a first positive electrode uncoated portion that is an area where the positive electrode active material is not applied; An anode tab attached to the first anode uncoated portion; A negative electrode plate including a negative electrode active material portion coated with a negative electrode active material on a first surface of the negative electrode current collector facing the first surface of the positive electrode current collector and a first negative electrode uncoated portion that is a region uncoated with the negative electrode active material; And a separator between the positive electrode plate and the negative electrode plate, wherein the first positive electrode uncoated portion is located between one end and the other end of the positive electrode plate along a length direction of the positive electrode plate, and the first negative electrode uncoated portion It is formed at a position overlapping the negative, the first negative electrode uncoated portion is formed on both sides of the negative electrode plate, and is formed between the second negative electrode uncoated portion and the third negative electrode uncoated portion to which the negative electrode tab is attached, and the first negative electrode uncoated portion An electrode assembly further comprising a negative electrode tab provided in the portion.
[Claim 19]
The method according to claim 18, wherein the positive electrode plate further comprises a second positive electrode uncoated portion in which the positive electrode active material is not applied, the positive electrode tab is further attached to the second positive positive electrode uncoated portion, and the negative electrode plate is not coated with the negative electrode active material. The electrode assembly further includes a second negative electrode uncoated portion and a third negative electrode uncoated portion as regions, wherein the negative electrode tab is further attached to the second negative electrode uncoated portion and the third negative electrode uncoated portion.
[Claim 20]
The method of claim 19, wherein the electrode assembly is an electrode assembly for a lithium ion secondary battery, wherein the positive electrode plate, the separator, and the negative electrode plate are alternately stacked and wound, and cover the negative electrode tab attached to the first negative electrode uncoated part. A first negative electrode insulating tape is further attached to the first negative electrode uncoated part, and a lithium ion precipitation prevention tape is further attached to the positive electrode plate portion facing the first negative electrode insulating tape to prevent lithium ions from accumulating and depositing during charging and discharging. Electrode assembly.
[Claim 21]
The electrode assembly of claim 20, wherein the first negative electrode uncoated portion and the lithium ion precipitation preventing tape are faced to each other with the separator interposed therebetween, and the lithium ion precipitation preventing tape is located on a surface of the positive electrode active material part of the positive electrode plate.
[Claim 22]
The method according to any one of claims 18 to 21, wherein the positive electrode tab attached to the first positive electrode uncoated portion and the negative electrode tab attached to the first negative negative electrode uncoated portion are formed in a direction in which the positive electrode plate and the negative electrode plate face each other. Electrode assembly provided so as not to overlap with each other.