Electrode assembly and secondary battery including the same

Abstract

The present invention relates to an electrode assembly, wherein a first electrode and a second electrode are wound into a jelly roll shape with a separator interposed therebetween, the electrode assembly comprising: a first electrode, comprising a first winding starting portion disposed at a winding starting point and having no first electrode active material, a first winding ending portion disposed at a winding ending point and having no first electrode active material, and a first coating portion disposed between the first winding starting portion and the first winding ending portion and coated with the first electrode active material; a second electrode, comprising a second winding starting portion disposed at a winding starting point and having no second electrode active material, a second winding ending portion disposed at a winding ending point and having no second electrode active material, and a second coating portion disposed between the second winding starting portion and the second winding ending portion and coated with the second electrode active material; an electrode sheet portion, comprising a first electrode sheet disposed at the first winding ending portion of the first electrode and a second electrode sheet disposed at the second winding starting portion of the second electrode; and a first protective member attached to a surface of the second winding ending portion of the second electrode facing the first electrode sheet.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2019-0142204, filed on November 8, 2019, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present invention relates to an electrode assembly having heat dissipation performance and a secondary battery including the electrode assembly. Background Art

[0004] Generally, secondary batteries refer to batteries that are both rechargeable and dischargeable, unlike non-rechargeable primary batteries. Secondary batteries are widely used in high-tech electronics such as mobile phones, laptop computers, and camcorders.

[0005] Secondary batteries are classified into can-type secondary batteries in which an electrode assembly is embedded in a metal can and pouch-type secondary batteries in which an electrode assembly is embedded in a bag. A can-type secondary battery includes an electrode assembly, a can accommodating the electrode assembly, and a cap assembly mounted on the opening of the can, and the electrode assembly has a structure in which electrodes and separators are alternately stacked. In addition, the electrode includes a first electrode and a second electrode. The first electrode is coupled to the can via a first electrode tab, and the second electrode is coupled to the cap assembly via a second electrode tab.

[0006] However, in the above-mentioned secondary battery, when a short circuit occurs when the first electrode and the second electrode contact each other, the temperature of the electrode assembly may increase. In this case, when the heat generated in the electrode assembly is not quickly dissipated, the temperature of the electrode assembly increases rapidly, causing explosion and fire. Summary of the invention

[0007] Technical issues

[0008] The present invention is invented to solve the above problems, and an object of the present invention is to provide an electrode assembly capable of quickly dissipating heat generated therein to the outside to prevent the electrode assembly from exploding or catching fire, and a secondary battery including the same.

[0009] Solution

[0010] According to the present invention for achieving the above-mentioned purpose, an electrode assembly, wherein a first electrode and a second electrode are wound into a jelly roll shape, with a separator inserted between the first electrode and the second electrode, the electrode assembly comprising: a first electrode, comprising a first winding start portion disposed at a winding start point and having no first electrode active material, a first winding end portion disposed at a winding end point and having no first electrode active material, and a first coating portion disposed between the first winding start portion and the first winding end portion and coated with the first electrode active material; a second electrode, comprising a second winding start portion disposed at a winding start point and having no second electrode active material, a second winding end portion disposed at a winding end point and having no second electrode active material, and a second coating portion disposed between the second winding start portion and the second winding end portion and coated with the second electrode active material; an electrode sheet portion, comprising a first electrode sheet disposed at the first winding end portion of the first electrode and a second electrode sheet disposed at the second winding start portion of the second electrode; and a first protective member attached to a surface of the second winding end portion of the second electrode facing the first electrode sheet.

[0011] The first protection member may be made of a material having heat dissipation properties.

[0012] The area of ​​the first protection member may be larger than the area of ​​the first electrode sheet disposed in the first winding end portion.

[0013] The electrode assembly may further include a second protection member attached to a surface of the first winding start portion of the first electrode facing the second electrode sheet.

[0014] The second protection member may be made of a material having heat dissipation properties.

[0015] The area of ​​the second protection member may be larger than the area of ​​the second electrode sheet disposed in the second winding start portion.

[0016] An area of ​​the first protective member may be greater than an area of ​​the second protective member.

[0017] When viewed in the longitudinal direction of the first electrode, the first winding start portion and the first winding end portion may have different lengths from each other, wherein the length of the first winding end portion may be greater than the length of the first winding start portion.

[0018] When viewed in the longitudinal direction of the second electrode, the second winding start portion and the second winding end portion may have different lengths from each other, wherein the length of the second winding end portion may be greater than the length of the second winding start portion.

[0019] A first guard tape may be attached to the first electrode sheet, and the first guard tape may be made of a material having heat dissipation properties.

[0020] The second guard tape may be attached to the second electrode sheet, and the second guard tape may be made of a material having heat dissipation properties.

[0021] The first electrode may be a positive electrode, and the second electrode may be a negative electrode.

[0022] The first protective member can be attached to one surface of the second winding end portion of the second electrode facing the first electrode sheet, the auxiliary member can be attached to the other surface of the second winding end portion of the second electrode corresponding to the first protective member, and the first protective member and the auxiliary member can be connected to each other via a connecting portion passing through the second winding end portion.

[0023] The first protective member, the auxiliary member, and the connection portion may be integrally formed and made of a material having heat dissipation properties.

[0024] A secondary battery according to the present invention includes: an electrode assembly, wherein a first electrode and a second electrode are wound into a jelly roll shape with a separator interposed between the first electrode and the second electrode; and a case configured to accommodate the electrode assembly, wherein the electrode assembly includes: a first electrode, which includes a first winding start portion disposed at a winding start point and having no first electrode active material, a first winding end portion disposed at a winding end point and having no first electrode active material, and a first coating portion disposed between the first winding start portion and the first winding end portion and coated with the first electrode active material; a second electrode, which includes a second winding start portion disposed at a winding start point and having no second electrode active material, a second winding end portion disposed at a winding end point and having no second electrode active material, and a second coating portion disposed between the second winding start portion and the second winding end portion and coated with the second electrode active material; an electrode sheet portion, which includes a first electrode sheet disposed at the first winding end portion of the first electrode and a second electrode sheet disposed at the second winding start portion of the second electrode; and a first protective member attached to a surface of the second winding end portion of the second electrode facing the first electrode sheet.

[0025] Beneficial effects

[0026] The electrode assembly according to the present invention may include a first protective member attached to a surface of the second winding end portion of the second electrode facing the first electrode sheet. Therefore, the first electrode sheet and the second electrode may be prevented from contacting each other to prevent a short circuit in advance, thereby improving stability.

[0027] In particular, in the electrode assembly according to the present invention, the first protective member may be made of a material having heat dissipation performance. Therefore, the heat generated in the electrode assembly can be quickly dissipated to the outside, and therefore, the temperature rise of the electrode assembly can be suppressed to prevent the secondary battery from exploding or catching fire. In particular, the first protective member can effectively dissipate the heat generated between the first electrode sheet and the second electrode.

[0028] In addition, in the electrode assembly according to the present invention, the area of ​​the first protective member can be larger than the area of ​​the first electrode sheet arranged in the first winding end portion of the first electrode. Therefore, the heat dissipation performance of the electrode assembly can be greatly improved, and in particular, the heat generated in the first electrode sheet and the first winding end portion of the first electrode to which the first electrode sheet is attached can be quickly dissipated to the outside.

[0029] In addition, in the electrode assembly according to the present invention, the second protective member can also be attached to the surface of the first winding start portion of the first electrode facing the second electrode sheet. Therefore, the second electrode sheet and the first electrode can be prevented from contacting each other, and the temperature increase of the electrode assembly can be suppressed to prevent the electrode assembly from exploding or catching fire.

[0030] In particular, in the electrode assembly according to the present invention, the second protective member can be made of a material having the same heat dissipation performance as the first protective member. Therefore, the heat generated in the electrode assembly can be quickly dissipated to the outside, and therefore, the temperature increase of the electrode assembly can be suppressed to prevent the electrode assembly from exploding or catching fire. In particular, the second protective member can effectively dissipate the heat generated between the second electrode sheet and the first electrode.

[0031] In addition, in the electrode assembly according to the present invention, the second electrode may include a second winding start portion and a second winding end portion, and the length of the second winding end portion may be greater than the length of the second winding start portion. Therefore, since the heat generated in the electrode assembly is effectively dissipated by the first protective member and the second protective member, the length of the second winding start portion can be minimized, and the length of the second winding end portion can be increased to improve the adhesive force and heat dissipation performance.

[0032] In addition, in the electrode assembly according to the present invention, the first and second protective tapes having heat dissipation properties can be attached to the first and second electrode sheets. Therefore, the heat generated in the first and second electrode sheets can be effectively dissipated, and therefore, the temperature rise of the electrode assembly can be significantly suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is an exploded perspective view showing a state before the electrode assembly according to the first embodiment of the present invention is wound.

[0034] Figure 2 yes Figure 1 Floor plan.

[0035] Figure 3 is along Figure 2 A cross-sectional view taken along line AA in FIG.

[0036] Figure 4 is along Figure 2 A cross-sectional view taken along line BB in FIG.

[0037] Figure 5 is a front view showing a first protective tape of an electrode assembly provided in a secondary battery according to a first embodiment of the present invention.

[0038] Figure 6 is a front view showing a second protective tape of the electrode assembly provided in the secondary battery according to the first embodiment of the present invention.

[0039] Figure 7 is a perspective view of a secondary battery according to a second embodiment of the present invention.

[0040] Figure 8 is a cross-sectional view of an electrode assembly according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings in a manner in which a person skilled in the art can easily implement the technical ideas of the present invention. However, the present invention can be implemented in different forms and should not be construed as being limited to the embodiments described herein. In the accompanying drawings, any content that is not necessary for describing the present invention will be omitted for clarity, and the same reference numerals in the drawings represent the same elements.

[0042] [Electrode Assembly According to First Embodiment of the Present Invention]

[0043] like Figures 1 to 6 As shown, the electrode assembly 100 according to the first embodiment of the present invention has a structure in which a first electrode and a second electrode are wound in a jelly roll shape with a separator interposed therebetween.

[0044] For example, in the electrode assembly 100 according to the first embodiment of the present invention, when Figure 1 When viewed in FIG. 1 , the first electrode 110, the separator 120, the second electrode 130, and the separator 140 are sequentially stacked in the front-to-back direction, and also from the winding starting point (when in FIG. Figure 1 left end when viewed from the center) to the winding end point (when Figure 1 The right end when viewed in the middle) is rolled into a jelly roll shape.

[0045] First electrode

[0046] The first electrode 110 includes: a first winding starting portion 111, which is disposed at a winding starting point and does not have a first electrode active material; a first winding ending portion 112, which is disposed at a winding ending point and does not have a first electrode active material; and a first coating portion 113, which is disposed between the first winding starting portion 111 and the first winding ending portion 112 and is coated with the first electrode active material.

[0047] Second electrode

[0048] The second electrode 130 includes: a second winding starting portion 131, which is arranged at the winding starting point and does not have a second electrode active material; a second winding ending portion 132, which is arranged at the winding ending point and does not have a second electrode active material; and a second coating portion 133, which is arranged between the second winding starting portion 131 and the second winding ending portion 132 and is coated with the second electrode active material.

[0049] The electrode assembly 100 according to the first embodiment of the present invention includes an electrode sheet part 150 .

[0050] Electrode sheet

[0051] The electrode sheet portion 150 includes a first electrode sheet 151 disposed at the first winding end portion 112 of the first electrode 110 and a second electrode sheet 152 disposed at the second winding start portion 131 of the second electrode 130 .

[0052] The first electrode 110 is a positive electrode, and the second electrode 130 is a negative electrode. In addition, the first electrode sheet 151 is a positive electrode sheet, and the second electrode sheet 152 is a negative electrode sheet.

[0053] Here, the electrode assembly 100 according to the first embodiment of the present invention may include a positive electrode sheet, i.e., a first electrode sheet 151, at the first winding end portion 112 of the first electrode 110 to quickly dissipate heat generated in the positive electrode sheet to the outside when a short circuit occurs, thereby preventing the electrode assembly 100 from exploding or catching fire in advance. That is, when a short circuit occurs, more heat is generated in the positive electrode sheet than in the negative electrode sheet. Therefore, a positive electrode sheet may be provided at the first winding end portion 112 of the first electrode 110 disposed outside the electrode assembly to quickly dissipate heat generated in the positive electrode sheet to the outside.

[0054] First protection member

[0055] The electrode assembly 100 according to the first embodiment of the present invention may include a first protective member 160 attached to a surface of the second winding end portion 132 of the second electrode 130 facing the first electrode sheet 151. The first protective member 160 may prevent the second winding end portion 132 of the second electrode 130 from being deformed by the first electrode sheet 151, thereby preventing the first electrode sheet 151 and the second electrode 130 from contacting each other, thereby improving stability.

[0056] Here, the edge of the first protective member 160 also includes an extension portion extending out of the edge of the second winding end portion 132, and the extension portion is bent along the edge of the first protective member 160 and then attached to the other surface of the second winding end portion 132 to which the first protective member 160 is not attached. Therefore, the strength of the edge of the second winding end portion 132 can be increased.

[0057] The first protective member 160 may be made of a material having a heat dissipation property. That is, the electrode assembly 100 may generate high heat during charging and discharging or when a short circuit occurs. Therefore, the electrode assembly 100 may explode or catch fire due to the high heat. In order to prevent this phenomenon, in the electrode assembly 100 according to the first embodiment of the present invention, the first protective member 160 may be made of a material having a heat dissipation property. Therefore, the heat generated inside the electrode assembly 100 can be quickly dissipated to the outside through the first protective member to suppress the temperature increase of the electrode assembly 100, thereby preventing the electrode assembly 100 from exploding or catching fire.

[0058] Specifically, the first protection member 160 may be attached to the entire surface of the second winding finish portion 132 , and thus may increase heat dissipation from an upper portion to a lower portion of the outer surface of the electrode assembly 100 .

[0059] In addition, the area of ​​the first protective member 160 may be larger than the area of ​​the first electrode sheet 151 disposed in the first winding end portion 112. Therefore, the first electrode sheet 151 may be prevented from damaging the second winding end portion 132 of the second electrode 130, and the heat generated in the first electrode sheet 151 may be effectively absorbed by the first protective member 160 and then dissipated to the outside.

[0060] The surface of the first protective member 160 may have an uneven shape, and thus, the first protective member 160 may be easily bent to effectively dissipate heat through the unevenness.

[0061] Second protective member

[0062] The electrode assembly 100 according to the first embodiment of the present invention may include a second protective member 170 attached to a surface of the first winding start portion 111 of the first electrode 110 facing the second electrode sheet 152. The second protective member 170 may support the second electrode sheet 152 to prevent the first winding start portion 111 of the first electrode 110 from being deformed by the second electrode sheet 152, thereby preventing the second electrode sheet 152 and the first electrode 110 from contacting each other, thereby improving stability.

[0063] The second protective member 170 may be made of a material having heat dissipation properties. That is, the electrode assembly 100 may generate high heat during charging and discharging or when a short circuit occurs. Therefore, the electrode assembly 100 may explode or catch fire due to the high heat. In particular, the second protective member 170 can effectively dissipate the heat generated in the core of the electrode assembly 100, thereby significantly suppressing the temperature increase of the electrode assembly 100.

[0064] Here, the area of ​​the second protection member 170 may be greater than that of the second electrode sheet 152 to prevent the first winding start portion 111 from being deformed by the second electrode sheet 152 .

[0065] The surface of the second protective member 170 may have an uneven shape, and thus, the second protective member 170 may be easily bent to effectively dissipate heat through the unevenness. That is, the second protective member 170 may have a plurality of grooves formed in the longitudinal direction of the first electrode 110, and the grooves are formed lengthwise in the width direction of the first electrode. Therefore, the second protective member 170 may be easily bent through the grooves, and thus, the first winding start portion 111 of the first electrode 110 to which the second protective member 170 is attached may be easily wound.

[0066] The area of ​​the first protective member 160 may be greater than that of the second protective member 170. Thus, the area of ​​the first protective member 160 surrounding the outside of the electrode assembly 100 may be increased to more easily dissipate heat generated in the electrode assembly 100. The area of ​​the second protective member 170 may be smaller than that of the first protective member 160 to significantly reduce an increase in the volume of the core of the electrode assembly 100.

[0067] When viewed in the longitudinal direction of the first electrode 110, the first winding start portion 111 and the first winding end portion 112 have different lengths. Here, the length of the first winding end portion 112 may be greater than the length of the first winding start portion 111. That is, since the electrode sheet is not attached to the first winding start portion 111, the size is minimized, and since the electrode sheet is attached to the first winding end portion 112, the size is increased to the maximum extent. Therefore, the electrode sheet can be stably attached.

[0068] When viewed in the longitudinal direction of the second electrode 130, the second winding start portion 131 and the second winding end portion 132 have different lengths. Here, the length of the second winding end portion 132 may be greater than the length of the second winding start portion 131. Here, the second winding end portion 132 has a size corresponding to the size of the first winding end portion 112. Therefore, the second winding end portion 132 may effectively cover the first winding end portion 112. In particular, the area of ​​the first protective member 160 may be significantly increased, and therefore, the heat dissipation of the electrode assembly 100 may be increased.

[0069] First protection belt

[0070] In the electrode assembly 100 according to the first embodiment of the present invention, the first protective tape 180 may be attached to the first electrode sheet 151. The first protective tape 180 may remove a height difference between the first electrode sheet 151 and the first winding finisher 112 and may prevent the first electrode sheet 151 from damaging the separator 120.

[0071] In addition, the first protective tape 180 is made of a material having heat dissipation properties, and thus, heat generated in the core of the electrode assembly 100 may be quickly dissipated to the outside.

[0072] The first protective tape 180 and the first protective member 160 may have the same size, thickness, and material to prevent the first protective tape 180 and the first protective member 160 from damaging the electrode.

[0073] Second protection belt

[0074] In the electrode assembly 100 according to the first embodiment of the present invention, the second protective tape 190 may be attached to the second electrode sheet 152. The second protective tape 190 may remove a height difference between the second electrode sheet 152 and the second winding start portion 131 and may prevent the second electrode sheet 152 from damaging the separator 140.

[0075] Particularly, the second guard tape 190 is made of a material having heat dissipation properties, and thus, heat generated in the second electrode sheet 152 may be effectively dissipated.

[0076] Here, the second protective tape 190 and the second protective member have the same size, thickness, and material.

[0077] Therefore, the electrode assembly 100 according to the first embodiment of the present invention may quickly dissipate heat generated at the outside and inside of the electrode assembly to the outside to prevent the electrode assembly from exploding or catching fire.

[0078] Hereinafter, in description of another embodiment of the present invention, constituent elements having the same functions as those of the above-described embodiment are given the same reference numerals in the drawings, and thus repeated description will be omitted.

[0079] [Secondary Battery According to Second Embodiment of the Invention]

[0080] like Figure 7 As shown, a secondary battery according to a second embodiment of the present invention includes an electrode assembly 100 in which a first electrode and a second electrode are wound in a jelly roll shape with a separator interposed therebetween, and a case 200 accommodating the electrode assembly 100 .

[0081] Here, the electrode assembly includes a first electrode, a separator, a second electrode, and a separator.

[0082] The first electrode includes: a first winding start portion, which is arranged at a winding start point and does not have a first electrode active material; a first winding end portion, which is arranged at a winding end point and does not have a first electrode active material; and a first coating portion, which is arranged between the first winding start portion and the first winding end portion and is coated with the first electrode active material.

[0083] The second electrode includes: a second winding starting portion, which is arranged at the winding starting point and does not have a second electrode active material; a second winding ending portion, which is arranged at the winding ending point and does not have a second electrode active material; and a second coating portion, which is arranged between the second winding starting portion and the second winding ending portion and is coated with the second electrode active material.

[0084] In addition, the electrode assembly includes an electrode sheet portion. The electrode sheet portion includes: a first electrode sheet disposed at a first winding end portion of the first electrode; and a second electrode sheet disposed at a second winding start portion of the second electrode.

[0085] Here, the electrode assembly includes: a first protective member on a surface of the second winding end portion of the second electrode facing the first electrode sheet; and a second protective member attached to a surface of the first winding start portion of the first electrode facing the second electrode sheet. Therefore, heat generated in the electrode assembly can be effectively dissipated by the first protective member and the second protective member.

[0086] Therefore, in the secondary battery according to the second embodiment of the present invention, heat generated in the electrode assembly may be effectively dissipated.

[0087] [Electrode assembly according to a third embodiment of the present invention]

[0088] like Figure 8As shown, the electrode assembly 100 according to the third embodiment of the present invention has the following structure: in the structure, the first protective member 160 is attached to one surface of the second winding end portion 132 of the second electrode 130, the auxiliary member 161 is attached to the other surface of the second winding end portion 132 of the second electrode 130 facing the first protective member 160, and the first protective member 160 and the auxiliary member 161 are connected to each other via a connecting portion 162 passing through the second winding end portion 132.

[0089] Here, the first protective member 160 , the auxiliary member 161 , and the connection portion 162 are integrally formed and made of a material having heat dissipation properties.

[0090] Therefore, the electrode assembly 100 according to the third embodiment of the present invention may disperse the heat transferred to the first protective member 160 to the auxiliary member 161 through the connection part 162 to more effectively dissipate the heat generated in the electrode assembly 100 .

[0091] A plurality of connection parts 162 may be provided. Thus, the first protective member 160 and the auxiliary member 161 may be connected to each other through the plurality of connection parts 162, and thus, heat transferred to the first protective member 160 may be dispersed to the auxiliary member 161 more quickly.

[0092] Therefore, the scope of the present invention is defined by the appended claims rather than the above description and the exemplary embodiments described herein. Various modifications made within the meaning of equivalents of the claims of the present invention and various modifications made within the claims are considered to be within the scope of the present invention.

[0093] [reference numerals]

[0094] 100: Electrode assembly

[0095] 110: First electrode

[0096] 120, 140: Divider

[0097] 130: Second electrode

[0098] 150: Electrode sheet

[0099] 160: First protection member

[0100] 170: Second protection member

[0101] 180: First protection zone

[0102] 190: Second protection zone

Claims

1. An electrode assembly, wherein a first electrode and a second electrode are wound into a jelly roll shape, with a separator between the first electrode and the second electrode, the electrode assembly include: A first electrode, comprising: a first winding start portion, which is disposed at a winding start point and does not have a first electrode active material; a first winding end portion, which is disposed at a winding end point and does not have the first electrode active material; and a first coating portion, which is disposed between the first winding start portion and the first winding end portion and is coated with the first electrode active material; a second electrode, comprising: a second winding start portion, which is disposed at a winding start point and does not have a second electrode active material; a second winding end portion, which is disposed at a winding end point and does not have the second electrode active material; and a second coating portion, which is disposed between the second winding start portion and the second winding end portion and is coated with the second electrode active material; an electrode sheet portion, comprising: a first electrode sheet disposed at a first winding end portion of the first electrode; and a second electrode sheet disposed at a second winding start portion of the second electrode; and a first protective member attached to a surface of a second winding end portion of the second electrode facing the first electrode sheet, wherein the first protective member is attached to the entire surface of the second winding end portion.

2. The electrode assembly according to claim 1, in, The first protection member is made of a material having heat dissipation performance.

3. The electrode assembly according to claim 1, in, The first protection member has an area larger than an area of ​​the first electrode sheet disposed in the first winding end portion. 4 . The electrode assembly according to claim 1 , further comprising a second protection member attached to a surface of the first winding start portion of the first electrode facing the second electrode sheet.

5. The electrode assembly according to claim 4, in, The second protection member is made of a material having heat dissipation performance.

6. The electrode assembly according to claim 4, in, The second protection member has an area larger than an area of ​​the second electrode sheet disposed in the second winding start portion.

7. The electrode assembly according to claim 4, in, An area of ​​the first protection member is greater than an area of ​​the second protection member.

8. The electrode assembly according to claim 1, in, When viewed along the longitudinal direction of the first electrode, the first winding start portion and the first winding end portion have different lengths from each other, Wherein, the length of the first winding end portion is greater than the length of the first winding start portion.

9. The electrode assembly according to claim 1, in, When viewed along the longitudinal direction of the second electrode, the second winding start portion and the second winding end portion have different lengths from each other, Wherein, the length of the second winding end portion is greater than the length of the second winding start portion.

10. The electrode assembly according to claim 1, in, A first protective tape is attached to the first electrode sheet, and The first protection tape is made of a material having heat dissipation performance.

11. The electrode assembly according to claim 1, wherein, a second protective tape is attached to the second electrode sheet, and the second protective tape is made of a material having heat dissipation performance.

12. The electrode assembly according to claim 1, wherein, the first electrode is a positive electrode and the second electrode is a negative electrode.

13. The electrode assembly according to claim 1, wherein, the first protective member is attached to one surface of the second winding end portion of the second electrode facing the first electrode sheet, an auxiliary member is attached to the other surface of the second winding end portion of the second electrode corresponding to the first protective member, and the first protective member and the auxiliary member are connected to each other via a connecting portion passing through the second winding end portion.

14. The electrode assembly according to claim 13, wherein, the first protective member, the auxiliary member and the connecting portion are integrally formed and made of a material having heat dissipation performance.

15. A secondary battery, comprising: an electrode assembly in which a first electrode and a second electrode are wound into a jelly roll shape with a separator between the first electrode and the second electrode; and a case configured to accommodate the electrode assembly, wherein the electrode assembly includes: a first electrode including: a first winding start portion provided at a winding start point and not having a first electrode active material; a first winding end portion provided at a winding end point and not having the first electrode active material; and a first coating portion provided between the first winding start portion and the first winding end portion and coated with the first electrode active material; a second electrode including: a second winding start portion provided at a winding start point and not having a second electrode active material; a second winding end portion provided at a winding end point and not having the second electrode active material; and a second coating portion provided between the second winding start portion and the second winding end portion and coated with the second electrode active material; an electrode sheet portion including: a first electrode sheet provided at the first winding end portion of the first electrode; and a second electrode sheet provided at the second winding start portion of the second electrode; and a first protective member attached to the surface of the second winding end portion of the second electrode facing the first electrode sheet, wherein the first protective member is attached to the entire surface of the second winding end portion.

Images