KR20040043039A - Jelly-roll type electrode assembly and secondary cell therewith - Google Patents

Abstract

PURPOSE: A jelly-roll type electrode assembly and a secondary battery provided with the electrode assembly are provided, to improve the structural stability and thermal stability at a winding central part. CONSTITUTION: The jelly-roll type electrode assembly comprises a first electrode plate(30) which has (i) a first electrode coating part where a first electrode active mass(32) containing a first electrode active material is formed in a first electrode current collector(31) and (ii) a first electrode uncoated part where the first electrode active mass is not formed in a first electrode current collector, and is wound with an interposed separator(50) (wherein at lest the first electrode uncoated part is wound at the winding central part); a first electrode tap which is adhered to the first electrode uncoated part and projected; and a second electrode plate(40) which has (i) a second electrode coating part where a second electrode active mass containing a second electrode active mass(42) is formed in a second electrode current collector(41) and (ii) a second electrode uncoated part where the second electrode active mass is not formed in a second electrode current collector, and is wound with an interposed separator from a certain position of the outer face of the first electrode plate. The second electrode coating part is wound from the position where at least first electrode tap is adhered to the outer face of the first electrode uncoated part wound at the winding central part.

Description

Jelly-roll type electrode assembly and secondary battery having the same {Jelly-roll type electrode assembly and secondary cell therewith}

The present invention relates to a jelly roll electrode assembly having a positive electrode, a separator, and a negative electrode wound together, and a secondary battery having the same. More particularly, the present invention relates to a jelly roll electrode assembly and a secondary battery having the same, which enhance the structural and thermal stability of the battery. It is about.

Rechargeable batteries can be recharged, miniaturized and large-capacity, and typically, nickel-hydrogen (Ni-MH) batteries, lithium (Li) batteries, lithium-ion (Li-ion) batteries, and polymer lithium (PLI) batteries are used. In addition, such a secondary battery is divided into a cylindrical battery, a square battery, and a pouch-type battery that houses an electrode jelly roll in a pouch.

These secondary batteries use a jelly roll type electrode assembly in which a separator is inserted and wound between a positive electrode and a negative electrode formed by applying an active material to a substrate, drying, roll pressing and cutting the substrate. In other words, the cylindrical battery stores the electrode assembly in a cylindrical can, injects electrolyte, and seals it. The square battery compresses the electrode assembly to flatten it and stores it in the square can.

1 is a cross-sectional view showing a wound state of the jelly roll type electrode assembly with respect to a cylindrical secondary battery among such secondary batteries.

Electrodes, such as the positive electrode and the negative electrode, are somewhat different depending on the type of battery, but generally, as shown in the figure, the positive electrode active material 3b and the negative electrode active material 4b are included on both surfaces of the current collectors 3a and 3b, respectively. It is produced by a process of applying a slurry, drying and roll pressing it, and then cutting it to a predetermined size. The positive electrode plate 3 and the negative electrode plate 4 thus prepared are interposed between the separators 5 so as not to be energized to each other, and then wound and manufactured in rolls.

The electrode assembly 2 is housed inside the can 1, a cap assembly connected to the positive electrode 3 of the electrode assembly 2 is installed on the top of the can 1, and then the electrolyte 1 is in the can 1. After injection, sealed to make a cylindrical battery.

Generally, in such a cylindrical cell, the negative electrode 4 is connected to the inner wall of the can 1 of the cell at the outermost side of the electrode assembly 2 or welded to the negative electrode current collector 4a. The negative electrode tab is connected to the bottom of the cap 1, and the positive electrode 3 is connected to the cap assembly by connecting a tab from the positive electrode current collector 3a of the core portion of the electrode assembly 2.

FIG. 2 is a partial enlarged cross-sectional view showing in more detail the winding structure of the core portion to which the positive electrode tab is bonded in the electrode assembly 2 as described above, and is an enlarged cross-sectional view of the portion A of FIG. 1.

As shown in FIG. 2, the separator 5 is wound around the innermost part of the electrode assembly 2, and thus the active material 3b is not applied to the current collector 3a of the positive electrode plate 3. The positive electrode uncoated portion 3c is wound up. At this time, the positive electrode tab 6 is joined to the inner side of the tip portion of the positive electrode current collector 3a. The positive electrode non-coating portion 3c is further wound in a state where the separator 5 is interposed on the inner side, and the negative electrode plate 4 on which the separator 5 is interposed on the inner side is wound together. In the negative electrode plate 4 at the core portion, the negative electrode non-coating portion 4c having no active material 4b coated thereon is formed on the current collector 4a, and the negative electrode coating portion immediately coated with the negative electrode active material 4b ( 4d) is wound, and the positive electrode coating 3d is also wound in the vicinity.

The secondary battery having the electrode assembly of the above structure should have a certain safety, for this purpose, the safety of the battery is evaluated before final production. Among these safety evaluations, the thermal safety evaluation is a high temperature preservation test for evaluating leakage or leakage of gas or stool by leaving it at a high temperature of 70 to 80 ° C. for evaluation of leakage, rupture, and ignition alternately between high and normal temperatures and low temperatures. A thermal shock test, and a thermal exposure test for evaluating rupture and ignition by leaving it for several ten minutes at a high temperature of 100 ° C. or higher are performed.

However, when the electrode assembly of the secondary battery as shown in FIGS. 1 and 2 is subjected to the thermal safety test as described above, the wound jelly roll structure collapses at a high temperature and there is a risk of short circuit. That is, when the jelly roll type electrode assembly is left at high temperature, the separator contracts, and the electrode active material and the separator are pressed together while being in a semi-melt state. Accordingly, as the jelly roll structure of the electrode assembly collapses, a short circuit between the positive electrode plate and the negative electrode plate may occur. In particular, the collapse phenomenon in the vicinity of the core, as seen in FIG. 2, becomes more problematic due to the positive electrode tab.

As can be seen in FIG. 2, the core part of the jelly roll type electrode assembly has a positive electrode tab 6 bonded to the innermost part of the positive electrode non-coating portion 3c, and the positive electrode non-coating portion 3c to which the positive electrode tab 6 is bonded. The anode uncoated portion 3c is continuously wound together with the separator 5 at the outer periphery, and after the cathode uncoated portion 3c is wound one or two or three or more times, the cathode uncoated portion 4c and the cathode coating portion are wound. 4d is wound up with the separator 5. Therefore, in this structure, since the positive electrode tab 6 is surrounded by the positive electrode non-coating portion 3c except for the separator 5 in the situation where the active materials and the separators of the electrode plates are stuck together at a high temperature, stable support is not achieved. Accordingly, the jelly roll structure is more easily collapsed at the portion where the positive electrode tab 6 is bonded, and a short circuit between the electrode plates is more easily caused by the protruding positive electrode tab 6.

The present invention has been made to solve the above problems, to provide a thermal stability and structural safety at the core portion, to provide a jelly roll electrode assembly and a secondary battery having the same that can improve the reliability of battery safety. Its purpose is to.

1 is a cross-sectional view showing the structure of a jelly roll electrode assembly of a conventional secondary battery.

FIG. 2 is a partially enlarged sectional view of the core part of FIG. 1. FIG.

3 is a cross-sectional view of a cylindrical battery having a jelly roll type electrode assembly according to a preferred embodiment of the present invention.

4 is a partially exploded perspective view showing an electrode plate of the jelly roll electrode assembly according to FIG. 3.

5 is a longitudinal sectional view of the cylindrical battery according to FIG. 3;

6 and 7 are partially enlarged cross-sectional views illustrating different embodiments in which the second electrode coating unit supports the first electrode tab according to the preferred embodiment of the present invention.

8 and 9 are partially enlarged cross-sectional views illustrating different embodiments in which the first electrode coating supports the first electrode tabs according to another exemplary embodiment of the present invention.

※ Explanation of code about main part of drawing ※

20: electrode assembly 30: first electrode plate

31: first electrode current collector 32: first electrode mixture

33: first electrode uncoated portion 34: first electrode coating portion

35: first electrode tab 40: second electrode plate

41: second electrode current collector 42: second electrode mixture

43: second electrode non-coating portion 44: second electrode coating portion

45: second electrode tab

In order to achieve the above object, the present invention provides a first electrode coating portion in which a first electrode mixture including a first electrode active material is formed in a first electrode current collector, and the first electrode mixture is provided in the first electrode current collector. A first electrode plate having no first electrode uncoated portion, and having a separator interposed on an inner surface thereof, the first electrode plate having at least a first electrode uncoated portion wound at the core portion, and a first electrode uncoated portion wound at the core portion. And a second electrode coating part having a second electrode mixture including a second electrode active material formed on the first electrode tab and the second electrode current collector protruding from each other, and a second electrode mixture not formed on the second electrode current collector. It has a two-electrode non-coated portion, the separator is interposed on the inner side is wound from a predetermined position of the outer side of the first electrode plate, the second electrode coated portion outside the first electrode uncoated portion wound in the core portion Including at least a first electrode tab a second electrode plate to be wound from the bonding position of providing the electrode assembly of a jelly roll, characterized in that formed.

According to another feature of the invention, the second electrode coating portion wound in the core portion may be wound from a position covering at least the first electrode tab of the outer surface of the first electrode uncoated portion.

According to another feature of the present invention, the second electrode coating portion wound in the core portion may be wound from at least an intermediate position of the first electrode tab of the outer surface of the first electrode uncoated portion.

In order to achieve the above object, the present invention provides a jelly roll-type electrode assembly wound through a separator so that the first electrode plate and the second electrode plate are insulated from each other, wherein the first electrode plate is disposed on the first electrode current collector. A first electrode coating portion having a first electrode mixture including a first electrode active material formed thereon, and a first electrode non-coating portion in which the first electrode mixture is not formed on the first electrode current collector; Wherein the first electrode non-coating portion, to which the first electrode tab is bonded, is wound, and the first electrode coating portion is wound from a position where at least the first electrode tab of the outer surface of the first electrode non-coating portion, which is wound at the core portion, is bonded. It provides a jelly roll type electrode assembly.

According to another aspect of the present invention, the first electrode coating portion wound in the core portion may be wound from a position covering at least the first electrode tab of the outer surface of the first electrode uncoated portion.

According to another feature of the present invention, the first electrode coating portion wound in the core portion may be wound from at least an intermediate position of the first electrode tab of the outer surface of the first electrode uncoated portion.

In order to achieve the above-described object, the present invention also provides a first electrode plate and a second electrode plate, each having an electrode coating portion formed with an electrode mixture including an electrode active material on an electrode current collector, and an uncoated electrode uncoated portion, and insulated from each other. Wound around the separator so that at least a first electrode non-coating portion is wound around the core portion, and the first electrode coating portion or the second electrode coating portion is at least made of an outer surface of the first electrode non-coating portion portion wound around the core portion. The electrode assembly of the jelly roll type wound from the position where the one electrode tab is bonded and the electrode assembly is accommodated and sealed, and provided with a first and second electrode terminal portions insulated from each other and electrically connected to the first and second electrode plates, respectively. It provides a secondary battery comprising a battery case.

According to another feature of the invention, the first electrode coating portion or the second electrode coating portion wound at the core portion of the electrode assembly to be wound from a position covering at least the first electrode tab of the outer surface of the first electrode uncoated portion. Can be.

According to another feature of the invention, the first electrode coating portion or the second electrode coating portion wound at the core portion of the electrode assembly to be wound from at least an intermediate position of the first electrode tab of the outer surface of the first electrode uncoated portion. can do.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. In the present specification, as a preferred embodiment of the present invention, a cylindrical battery having the electrode jelly roll of the present invention will be described. However, this is not limited to a cylindrical battery, but a battery which can be provided with the same electrode jelly roll as this embodiment. Any form may be applicable.

3 is a cross-sectional view of a cylindrical battery having a jelly roll electrode assembly according to an embodiment of the present invention, Figure 4 is a partially exploded perspective view showing the electrode plate of the jelly roll electrode assembly according to Figure 3, Figure 5 is a view 3 is a longitudinal cross-sectional view of the cylindrical battery.

First, as shown in FIG. 3, a jelly roll-type electrode wound with a separator 50 interposed therebetween so that the first electrode plate 30 and the second electrode plate 40 are insulated from each other in the cylindrical can 10. The assembly 20 is housed. The cylindrical can 10 is made of a metal and can itself serve as a terminal of the first electrode plate or the second electrode plate, and according to a preferred embodiment of the present invention, the cylindrical can 10 is made of aluminum or an aluminum alloy. The second electrode plate may be electrically connected to form a second electrode terminal.

As shown in FIG. 4, the jelly roll electrode assembly 20 is formed by sequentially stacking the first separator 51, the first electrode plate 30, the second separator 52, and the second electrode plate 40. Then, it was wound up in the direction of the arrow to form a roll. According to a preferred embodiment of the present invention, the first electrode plate 30 may be provided as a positive electrode plate, the second electrode plate 40 may be provided as a negative electrode plate, but is not necessarily limited thereto. The polarity may be reversed. Hereinafter, the first electrode plate 30 is a positive electrode plate, and the second electrode plate 40 will be described with reference to the case provided with a negative electrode plate.

As can be seen in FIG. 4, each of the electrode plates 30 and 40 is formed of electrode mixtures 32 and 42 including an electrode active material on the electrode current collectors 31 and 41. As follows.

When the electrode assembly is used as an electrode assembly of a lithium secondary battery, the first electrode plate 30 may be used as a positive electrode plate. In this case, the first electrode current collector 31 is provided with a strip-shaped metal sheet, and preferably an aluminum sheet. The first electrode mixture 32 formed on at least one surface of the first electrode current collector 31 may be formed of a mixture containing a binder, a plasticizer, a conductive material, and the like in the first electrode active material of the lithium oxide. The first electrode plate 30 includes a first electrode coating part 34 having the first electrode mixture 32 formed on at least one surface of the first electrode current collector 31, and the first electrode current collector 31. ) Is provided as a first electrode uncoated portion 33 in which the first electrode mixture 32 is not formed.

Meanwhile, in the second electrode plate 40 used as the negative electrode plate, a copper thin plate may be used as the second electrode current collector 41, and a second electrode mixture formed on at least one surface of the second electrode current collector 41 ( 42) may be formed of a mixture containing a binder, a plasticizer, a conductive material, and the like, in the second electrode active material of the carbon material. The second electrode plate 40 includes a second electrode coating part 44 having the second electrode mixture 42 formed on at least one surface of the second electrode current collector 41, and the second electrode current collector 41. ) Is provided as a second electrode uncoated portion 43 in which the second electrode mixture 42 is not formed.

The first and second separators 51 and 52 are provided between the inner surface of the first electrode plate 30 and the first and second electrode plates 30 and 40, respectively. While insulating each other between the 30 and the second electrode plate 40, active material ions can be exchanged between the electrode plates 30 and 40. The first and second separators 51 and 52 may have a length sufficient to completely insulate the electrode plates 30 and 40 even when the electrode assembly is contracted and expanded.

On the other hand, as shown in Figure 5, the electrode assembly formed as described above, the first electrode tab 35 and the second electrode tab 45 is drawn out. The first electrode tab 35 and the second electrode tab 45 are respectively drawn out from the first electrode plate 30 and the outer second electrode plate 40 of the core part of the electrode assembly 20. The first electrode tab 35 is drawn upwards and is electrically connected to the cap assembly 12 which seals the can 10, and the second electrode tab 45 is drawn downwards and thus the bottom of the can 10. It is electrically connected to the protrusion 18 formed in the part. Accordingly, the cap assembly 12 to which the first electrode tab 35 is connected functions as a first electrode terminal portion, and the can 10 to which the second electrode tab 45 is connected is entirely a second electrode terminal portion. Function. Reference numeral 14, which is not described in FIG. 5, is an insulating plate 14 for fixing the electrode assembly 20. The junction structure of the electrode tabs 35 and 45 is not necessarily limited thereto, and the outermost portion of the electrode assembly 20 may be disposed on the outermost portion of the electrode assembly 20 without separately drawing the second electrode tab 45. ), And then the second electrode plate 40 may be bonded to the inner wall of the can 10.

Meanwhile, as shown in FIG. 4, the first electrode tab 35 is bonded to the first electrode uncoated portion 33 and drawn out, and is welded to an inner surface of a substantially front end portion of the first electrode uncoated portion 33. And an insulating tape adhered to the outer surface thereof.

In the electrode assembly having such a structure, the winding center portion, that is, the structure of the core portion will be described in more detail as follows.

First, according to a preferred embodiment of the present invention, the second electrode coating portion in the winding portion of the wound electrode assembly may be wound from the position where at least the first electrode tab of the outer surface of the first electrode uncoated portion is bonded. In this case, as shown in FIG. 6, the second electrode coating part 44 may be wound from a position covering at least the first electrode tab 35 on the outer surface of the first electrode uncoated part 33. That is, as shown in FIG. 6, the tip 44a of the second electrode coating part 44 wound around the core part is the tip 35a and the core O in the winding direction of the first electrode tab 35. ) Is to be disposed in front of the straight line (L1) connecting the (). Of course, a second separator 52 is interposed between the second electrode coating portion 44 and the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded to form a first electrode and a second electrode. Do not short circuit.

As such, the second electrode coating part 44 is wound from a position covering the first electrode tab 35 among the outer surfaces of the first electrode non-coating part 33 so that the jelly roll electrode assembly may be used in thermal safety evaluation such as thermal exposure test. The jelly roll structure collapses at the portion where the first electrode tab is joined to prevent a short circuit from occurring. That is, as shown in FIG. 6 to the outside of the 2nd separator 52 arrange | positioned to the outer side of the position where the 1st electrode tab 35 was joined among the 1st electrode support parts 33 wound by the core part, the 2nd When the second electrode coating part 44 of the electrode plate is positioned, when the temperature of the electrode assembly rises and sticks together between the electrode mixture including the separator and the electrode active material, the first electrode tab 35 The phenomenon in which the portion of the first electrode uncoated portion 33, the portion of the second separator 52 on the outer side thereof, and the second electrode coating portion 44 on the outer side thereof, stick together again occurs. A portion of the second electrode coating portion 44 serves to hold a portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded. Therefore, even when the jelly roll structure of the electrode assembly collapses due to the high temperature, the portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded is prevented from collapsing at the center portion, thereby shorting. The defective rate according to this can be reduced. Therefore, as can be seen in FIG.

As such, the portion of the second electrode coating portion 44 at the core portion may serve to hold the portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded. As described above, in the winding portion, the second electrode coating portion 44 should be wound from at least an intermediate position of the first electrode tab 35 among the outer surfaces of the first electrode uncoated portion 33. That is, as shown in FIG. 7, the straight line 44a of the second electrode coating part 44 wound around the core part connects the middle portion of the first electrode tab 35 and the core O to each other. It is to be arranged in front of the winding direction than L2). This is because at least a portion of the first electrode uncoated portion 33 to which the second electrode coating portion 44 and the first electrode tab 35 are bonded maintains a bonding force at a high temperature, at least the first electrode tab 35. This is because it must be wound from an intermediate position of).

This effect can also be realized by another preferred embodiment of the present invention as seen in FIG.

That is, as shown in FIG. 8, at the core portion of the wound electrode assembly, from the position where the first electrode coating portion 34 is joined at least the first electrode tab 35 on the outer surface of the first electrode uncoated portion 33 is bonded. It is to be wound up. In this case, as shown in FIG. 8, the first electrode coating part 34 may be wound from a position covering at least the first electrode tab 35 of the first electrode uncoated part 33, and the winding part Winding direction of the front end (34a) of the first electrode coating portion 34 wound in the winding direction than the straight line (L1) connecting the front end (35a) and the winding (O) in the winding direction of the first electrode tab 35 Can be placed in front of it.

As described above, the first electrode coating part 34 is wound from a position covering the first electrode tab 35 among the outer surfaces of the first electrode non-coating part 33. The first electrode coating part serves to support a portion of the jelly roll type electrode assembly to which the first electrode tab is bonded. That is, as shown in FIG. 8 to the outside of the 1st separator 51 of the outer side of the position where the 1st electrode tab 35 was joined among the 1st electrode uncoated parts 33 wound by the core part, a 1st electrode coating When the part 34 is positioned, when the temperature of the electrode assembly rises to cause sticking between the electrode mixture including the separator and the electrode active material, the first electrode uncoated part to which the first electrode tab 35 is bonded is formed. The phenomenon that the part of (33), the part of the 1st separator 51 of the outer side surface, and the 1st electrode coating part 34 of the outer side surface again stick together mutually arises, and this 1st electrode coating part 34 The portion of) serves to hold the portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded. Therefore, even when the jelly roll structure of the electrode assembly collapses due to the high temperature, the portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded is prevented from collapsing at the center portion, thereby shorting. The defective rate according to this can be reduced.

As such, the portion of the first electrode coating portion 44 at the core portion may serve to hold a portion of the first electrode uncoated portion 33 to which the first electrode tab 35 is bonded. As described above, in the winding portion, the first electrode coating portion 34 should be wound from at least an intermediate position of the first electrode tab 35 of the first electrode uncoated portion 33. That is, as shown in FIG. 9, the straight line 34a of the first electrode coating part 34 wound around the core part connects the middle portion of the first electrode tab 35 and the core O to each other. It is to be arranged in front of the winding direction than L2). As in the above-described embodiment according to FIG. 7, the portion of the first electrode uncoated portion 33 to which the first electrode coating portion 34 and the first electrode tab 35 are bonded has a bonding force at a high temperature. This is because it must be wound at least from an intermediate position of the first electrode tab 35 in order to maintain it.

As described above, in the jelly roll type electrode assembly in which the first electrode plate and the second electrode plate are wound through a separator, a first electrode non-coating portion in which the first electrode tab is joined at the core portion is formed of a separator. As the second electrode coating part or the first electrode coating part supports, the problem in which the first electrode tab is joined may collapse in the thermal safety evaluation, thereby causing a short circuit of the battery. This effect can also be obtained not only in the above thermal safety evaluation, but also in a test in which the temperature inside the battery increases, such as an overcharge and discharge test, and the active materials and the separator of the electrode assembly stick together, and the jelly roll structure may collapse. have.

According to the present invention having the above configuration, the following effects can be obtained.

First, the first electrode tab is bonded by supporting the second electrode coating portion or the first electrode coating portion through the separator in the portion of the first electrode uncoated portion to which the first electrode tab is bonded at the core portion of the jelly roll type electrode assembly. It is possible to prevent the problem that the broken parts cause a short circuit of the battery, and can give more confidence in the safety of the battery.

Second, structural safety at the core portion of the jelly roll type electrode assembly can be ensured to ensure battery safety under severe environments such as overcharging and discharging or high temperature or low temperature.

In the present specification, the present invention has been described with reference to limited embodiments, but various embodiments are possible within the spirit of the present invention. In addition, although not described, equivalent means will also be referred to as incorporated in the present invention. Therefore, the true scope of the present invention will be defined by the claims below.

Claims (9)

An inner surface having a first electrode coating portion in which a first electrode mixture including a first electrode active material is formed in a first electrode current collector, and a first electrode plain portion in which the first electrode mixture is not formed in the first electrode current collector; A first electrode plate wound around the separator and wound around at least the first electrode uncoated portion; A first electrode tab bonded to and protruding from the first electrode uncoated portion wound from the winding portion; And A second electrode coating portion having a second electrode mixture including a second electrode active material formed on a second electrode current collector, and a second electrode non-coating portion on which the second electrode mixture is not formed on the second electrode current collector; A separator is interposed therebetween to be wound from a predetermined position on the outer surface of the first electrode plate, and the second electrode coating portion is bonded to at least the first electrode tab on the outer surface of the first electrode uncoated portion wound on the core portion. And a second electrode plate wound from the electrode assembly of a jelly roll type. The method of claim 1, The electrode assembly of the jelly roll type, characterized in that the second electrode coating portion wound from the winding portion is wound from a position covering at least the first electrode tab of the outer surface of the first electrode uncoated portion. The method of claim 1, The electrode assembly of the jelly roll type, wherein the second electrode coating portion wound from the core portion is wound from at least an intermediate position of the first electrode tab among the outer surfaces of the first electrode uncoated portion. In the jelly roll-type electrode assembly wound through the separator so that the first electrode plate and the second electrode plate are insulated from each other, The first electrode plate may include a first electrode coating part in which a first electrode mixture including a first electrode active material is formed in a first electrode current collector, and a first electrode in which the first electrode mixture is not formed in the first electrode current collector. The first electrode non-coating portion, to which the first electrode tab is bonded, is wound on the core portion of the electrode assembly, and the first electrode coating portion is at least a first outer side surface of the first electrode non-coating portion portion wound around the core portion. A jelly roll type electrode assembly, wherein an electrode tab is wound from a bonded position. The method of claim 4, wherein And a first electrode coating portion wound from the core portion is wound from a position covering at least the first electrode tab of an outer surface of the first electrode uncoated portion. The method of claim 4, wherein The electrode assembly of the jelly roll type, characterized in that the first electrode coating portion wound from the core portion is wound from at least an intermediate position of the first electrode tab of the outer surface of the first electrode uncoated portion. The first electrode plate and the second electrode plate are wound through a separator so as to be insulated from each other by having an electrode coating part including an electrode mixture including an electrode active material and an uncoated electrode non-coating part in an electrode current collector, respectively, At least a first electrode uncoated portion is wound, and a jelly roll type in which the first electrode coated portion or the second electrode coated portion is wound from a position where at least a first electrode tab of the outer surface of the first electrode uncoated portion wound at the core portion is joined. An electrode assembly; And And a battery case accommodating and sealing the electrode assembly, the battery case including first and second electrode terminal parts electrically insulated from and electrically connected to the first and second electrode plates, respectively. The method of claim 7, wherein And a first electrode coating part or a second electrode coating part wound up from the core part of the electrode assembly is wound from a position covering at least the first electrode tab of an outer surface of the first electrode uncoated part. The method of claim 7, wherein The electrode assembly of the jelly roll type, characterized in that the first electrode coating portion or the second electrode coating portion wound in the core portion of the electrode assembly is wound from at least an intermediate position of the first electrode tab of the outer surface of the first electrode uncoated portion. .