KR102630997B1 - Secondary Battery - Google Patents

Abstract

The present invention has an electrode active material applied to one or both sides, a first side, a second side opposite the first side, a third side perpendicular to the first side and the second side, and a fourth side opposite the third side. A secondary battery including an electrode plate having sides is provided.
For example, it includes one or more connecting parts formed at the connecting part of the first side and the third side or the fourth side, or the connecting part between the second side and the third side or the fourth side, and the connecting part starts from the first side and A slope that continues to the 3rd or 4th side, or starts from the 2nd side and continues to the 3rd or 4th side, but is formed by depression in the inner direction of the pole plate, and forms an obtuse angle with respect to the 3rd or 4th side. A secondary battery including two or more parts is disclosed.

Description

Secondary battery

The present invention relates to secondary batteries.

In general, secondary batteries are batteries that can be charged and discharged, unlike primary batteries that cannot be recharged. Low-capacity batteries in which one battery cell is packaged in a pack are used in small, portable electronic devices such as mobile phones and camcorders. Large-capacity batteries with dozens of cells connected are used as a power source for driving motors such as electric bicycles, electric scooters, hybrid cars, and electric cars.

Secondary batteries are manufactured in various shapes. Representative shapes include square, cylindrical, and pouch shapes. They are constructed by housing an electrode assembly and an electrolyte together in a case, and installing a cap plate on the case. Additionally, an electrode tab, a positive electrode terminal, etc. are connected to the electrode assembly, and these are exposed or protruded to the outside through the cap plate.

The electrode assembly of a secondary battery is formed by a positive electrode plate, a negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate. The electrode assembly may be formed by winding a laminate of a positive electrode plate, a negative electrode plate, and a separator, or may be formed by stacking a plurality of positive electrode plates, a negative electrode plate, and a separator. A method of forming an electrode assembly by stacking a plurality of electrode plates alternately stacks positive and negative electrode plates with a separator as a boundary.

In order to produce laminated electrode plates, electrode sheets must be separated by cutting. In many cases, the electrode sheets are separated by methods such as punching while transporting the electrode sheets along the transfer line.

The present invention provides a secondary battery including an electrode sheet having cutting parts at the top and bottom to manufacture a plurality of electrode plates, and an electrode plate manufactured by cutting the electrode sheet.

The secondary battery according to the present invention has an electrode active material applied to one or both sides, a first side, a second side opposite the first side, a third side perpendicular to the first side and the second side, and the second side. It includes a pole plate having a fourth side opposite to the third side, a connection portion between the first side and the third side or the fourth side, or a connection portion between the second side and the third side or the fourth side. It includes one or more connection parts formed in, wherein the connection part starts from the first side and continues to the third side or the fourth side, or starts from the second side and continues to the third side or the fourth side. It is formed by being depressed in the inner direction of the electrode plate, and includes two or more inclined portions forming an obtuse angle with respect to the third side or the fourth side.

Here, the inclined portion includes a first inclined portion that starts from at least one of the first side and the second side and extends in the inner direction of the electrode plate to be inclined. And it may include a second inclined portion that starts from the end of the first inclined portion and extends in the inner direction of the electrode plate and is formed to be inclined.

Additionally, the first angle formed by the first inclined portion with respect to the third side or the fourth side may be greater than the second angle formed by the second inclined portion.

In addition, the inclined portion includes a first inclined portion that starts from at least one of the first side and the second side and extends toward the inside of the electrode plate to be inclined. and a second inclined portion starting from the end of the first inclined portion and extending in an inner direction of the electrode plate, forming an acute angle with respect to the third side or the fourth side, and an end of the second inclined portion. It may further include a third inclined portion that starts from and extends in an outward direction of the electrode plate and is formed to be inclined.

Additionally, the angle formed by the third inclined portion with respect to the third side or the fourth side may be 45° or more.

In addition, the connection portion includes a first connection portion formed on the first side and a second connection portion formed on the second side, and the second side of the electrode plate includes a parallel portion parallel to the first side and the It may include a curved portion starting from the end of the parallel portion and extending in the inner direction of the pole plate, and the inclined portion of the second connection portion formed on the second side may be formed by starting from the end of the curved portion and extending in the inner direction of the pole plate. .In addition, the inclined portion of the second connection portion formed on the second side of the electrode plate may include an inclined portion formed to be inclined starting from the second side and extending in the inner direction of the electrode plate.

In addition, the inclined portion of the first connection portion formed on the first side of the electrode plate includes: a first inclined portion that starts from the first side and extends in the inner direction of the electrode plate and is formed to be inclined; and a second inclined portion starting from the end of the first inclined portion and extending in an inner direction of the electrode plate, forming an acute angle with respect to the third side or the fourth side, and an end of the second inclined portion. It may further include a third inclined portion that starts from and extends in an outward direction of the electrode plate and is formed to be inclined.

Additionally, the inclined portion may further include at least one inclined portion forming a reservation based on the third side or the fourth side.

In addition, the inclined portion includes a first inclined portion that starts from at least one of the first side and the second side and extends toward the inside of the electrode plate to be inclined. a second inclined portion starting from the end of the first inclined portion and extending toward the inside of the electrode plate to be inclined; And it may include a third inclined portion that starts from at least one of the first side and the second side and extends in the inner direction of the electrode plate, and is inclined in a direction facing the first inclined portion and the second inclined portion.

The electrode sheet of the present invention is provided with cutting parts at the top and bottom, so that an obtuse-angled connection is formed in the electrode plate produced by cutting the electrode sheet, thereby reducing the precision required for equipment, and after the electrode sheet is laminated, it passes through rollers for laminating. This reduces the shock transmitted from the roller and prevents the active material coated on the top of the electrode plate from falling off.

1 is a plan view of an electrode sheet according to an embodiment of the present invention.
Figure 2 is an enlarged view of part A of Figure 1.
Figure 3 is a plan view of an electrode plate formed by cutting an electrode sheet according to an embodiment of the present invention.
Figure 4 is an enlarged view of part B of Figure 3.
Figure 5 is an enlarged view of portion B' of Figure 3.
Figure 6 shows that an active material is coated on an electrode plate according to an embodiment of the present invention and then injected between rollers.
Figure 7 illustrates coating an active material on an electrode plate and passing it through a roller according to an embodiment of the present invention.
Figure 8 is a plan view of an electrode sheet according to another embodiment of the present invention.
Figure 9 is an enlarged view of part C of Figure 8.
Figure 10 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention.
Figure 11 is an enlarged view of part D of Figure 10.
Figure 12 is an enlarged view of portion D' of Figure 10.
Figure 13 is a plan view of an electrode sheet according to another embodiment of the present invention.
Figure 14 is an enlarged view of part E of Figure 13.
Figure 15 is an enlarged view of part F of Figure 13.
Figure 16 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention.
Figure 17 is an enlarged view of part G of Figure 16.
Figure 18 is an enlarged view of part G' of Figure 16.
Figure 19 is an enlarged view of portion H of Figure 16.
Figure 20 is an enlarged view of portion H' of Figure 16.
Figure 21 is a plan view of an electrode sheet according to another embodiment of the present invention.
Figure 22 is an enlarged view of part G of Figure 21.
Figure 23 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention.
Figure 24 is an enlarged view of part H of Figure 23.
Figure 25 is an enlarged view of portion H' of Figure 23.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following examples may be modified into various other forms, and the scope of the present invention is as follows. It is not limited to examples. Rather, these embodiments are provided to make the disclosure more faithful and complete, and to fully convey the spirit of the invention to those skilled in the art.

In addition, in the drawings below, the thickness and size of each layer are exaggerated for convenience and clarity of explanation, and the same symbols refer to the same elements in the drawings. As used herein, the term “and/or” includes any one and all combinations of one or more of the listed items. In addition, the meaning of "connected" in this specification refers not only to the case where member A and member B are directly connected, but also to the case where member C is interposed between member A and member B to indirectly connect member A and member B. do.

Terms used herein are used to describe specific embodiments and are not intended to limit the invention. As used herein, the singular forms include the plural forms unless the context clearly indicates otherwise. Additionally, when used herein, “comprise, include,” and/or “comprising, including” refer to mentioned features, numbers, steps, operations, members, elements, and/or groups thereof. It specifies the presence and does not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and/or groups.

Although the terms first, second, etc. are used herein to describe various members, parts, regions, layers and/or parts, these members, parts, regions, layers and/or parts are limited by these terms. It is obvious that this cannot be done. These terms are used only to distinguish one member, component, region, layer or section from another region, layer or section. Accordingly, a first member, component, region, layer or portion described below may refer to a second member, component, region, layer or portion without departing from the teachings of the present invention.

Space-related terms such as “beneath,” “below,” “lower,” “above,” and “upper” are used to refer to an element or feature shown in a drawing. It can be used to facilitate understanding of other elements or features. These space-related terms are for easy understanding of the present invention according to various process states or usage states of the present invention, and are not intended to limit the present invention. For example, if an element or feature in a drawing is turned over, an element or feature described as “bottom” or “below” becomes “top” or “above.” Therefore, “below” is a concept encompassing “top” or “below.”

1 is a plan view of an electrode sheet according to an embodiment of the present invention. Figure 2 is an enlarged view of part A of Figure 1. Figure 3 is a plan view of an electrode plate formed by cutting an electrode sheet according to an embodiment of the present invention. Figure 4 is an enlarged view of part B of Figure 3. Figure 5 is an enlarged view of portion B' of Figure 3.

Referring to FIG. 1, the electrode sheet 100 according to an embodiment of the present invention may include an electrode plate 110, an electrode tab 120, and a cutting portion 130.

The electrode plate 110 is separated by being cut by the cutting portion 130, and the cut and separated electrode plate 110 may be a positive electrode plate or a negative electrode plate. An electrode assembly is formed by stacking a separator between the positive and negative electrode plates. That is, a separator is stacked on the positive electrode plate, a negative electrode plate is stacked on the separator, a positive electrode plate is stacked again on the upper surface of the separator over the negative electrode plate, and the separator and the negative electrode plate are sequentially stacked again to form an electrode assembly.

A coated portion coated with an active material is formed on one or both sides of the electrode plate 110, and an uncoated portion not coated with the active material is formed on the upper side thereof. The uncoated portion becomes a path for current flow between the electrode of the secondary battery and the outside.

When the electrode plate 110 is a positive electrode plate, the electrode sheet 100 may be made of a metal material such as aluminum, and an active material containing lithium-based oxide as a main component may be applied. When the electrode plate 110 is a negative electrode plate, the material of the electrode sheet 100 may be a metal material such as copper, and an active material containing carbon as a main component may be applied.

The separator serves to prevent short circuits between the positive and negative plates and to enable the movement of ions. Additionally, the separator may be made of polyethylene, polypropylene, or a composite film of polyethylene and polypropylene.

The electrode tab 120 may extend upward from the upper end of the electrode sheet 100 at regular intervals and be formed in the shape of a bar. Among the electrode plates 110, the electrode tab 120 of the positive electrode plate is stacked with the electrode tab 120 of the other positive electrode plate to form the positive electrode tab of the electrode assembly, and the electrode tab 120 of the negative electrode plate among the electrode plates 110 is stacked with the electrode tab 120 of the other positive electrode plate. It is laminated with the electrode tab 120 of the negative electrode plate to form the negative electrode tab of the electrode assembly.

Referring to FIG. 2, the cutting part 130 is formed by cutting the length of the electrode sheet 100 on the upper side 100a and the lower side 100b of the electrode sheet 100 in order to separate the electrode plate 110. A pair is formed to be symmetrical based on direction. Cutting portions 130 formed to correspond to each other on the upper side 100a and lower side 100b are formed at regular intervals along the longitudinal direction of the electrode sheet 100.

The cutting portion 130 may include a pair of first inclined portions 131 and second inclined portions 132. The pair of first inclined portions 131 and second inclined portions 132 may be formed to be symmetrical with respect to the direction CL in which the electrode sheet 100 is cut. The first inclined portion 131 extends from the upper side 100a and the lower side 100b of the electrode sheet 100 to the inside of the electrode sheet 100 and is inclined in a direction facing each other. In addition, the second inclined portion 132 extends from the end of the first inclined portion 131 to the inside of the electrode sheet 100 and is inclined in a direction facing each other. That is, the first angle θ11 of the first inclined portion 131 may be an obtuse angle greater than 90° based on the direction CL in which the electrode sheet 100 is cut, and the electrode sheet 100 The second angle θ12 of the second inclined portion 132 based on the cutting direction CL may also be an obtuse angle greater than 90°. Accordingly, one notch consisting of the first inclined portion 131 and the second inclined portion 132 may be formed in the cutting portion 130. Additionally, the first angle θ11 may be larger than the second angle θ12.

The portion cut by a cutting machine to separate the electrode plate 110 may be the second inclined portion 132. That is, it can be cut within the width W1 formed by the second inclined portion 132.

Referring to FIGS. 3, 4, and 5, the electrode plate 110 can be separated by cutting the second inclined portion 132 of the cutting portion 130 along the line indicated by ①. The separated electrode plate 110 is formed in a square shape with an upper side (first side), a lower side (second side), a right side (third side), and a left side (fourth side). And a first connection portion 150 is formed at a connection portion where the lower side and the right side meet, and a second connection portion 160 is formed at a connection portion where the upper side, the lower side, and the left side meet. If the second inclined portion 132 of the cutting portion 130 is cut along the line shown as ① to separate the electrode plate 110, the first connecting portion 150 is located on the upper side (or lower side). It starts and continues to the right side, and is formed by being depressed by the inner reflection of the pole plate, and includes two inclined portions (the first inclined portion 131 and the second inclined portion 132) that form an obtuse angle with respect to the right side. do. And, depending on the shape of the cutting portion 130 of the electrode sheet 100 before cutting, the first inclined portion 131 starts from the upper side or the lower side and extends in the inner direction of the electrode plate 110 to be inclined. The second inclined portion 132 starts from the end of the first inclined portion 131 and is formed to be inclined toward the inside of the electrode plate 110. The first connection portion 150 of the separated electrode plate 110 is formed as a part of the first inclined portion 131 and the second inclined portion 132, and its angle may be a second angle θ12. If the first inclined portion 131 of the cutting portion 130 is cut along the line shown in ② to separate the electrode plate 110, the first connecting portion 150 is located on the upper side (or lower side). It starts and continues to the right side, is formed by being depressed by the inner reflection of the electrode plate, and includes two inclined parts (first inclined parts 131) forming an obtuse angle with respect to the right side. In addition, even if the first inclined portion 131 is cut along the line shown as ② due to an error in the cutting machine, the first connecting portion 150 of the separated electrode plate 110 is the first inclined portion 131. It is made up of parts, and its angle may be the first angle (θ11). That is, the angle at the rightmost end of the first corner portion 150 may be an obtuse angle. Therefore, when the electrode plates 110 pass through the rollers 20 for laminating after being stacked, the impact transmitted from the rollers 20 can be reduced.

Meanwhile, the second connection portion 160 of the separated electrode plate 110 includes not only the first inclined portion 131 and the second inclined portion 132, but also another connecting portion paired with the second inclined portion 132. Further including a portion of the second inclined portion 132, the third angle θ13 of the second connection portion 160 may be an acute angle. However, even if the third angle θ13 of the second connection part 160 is an acute angle, as will be described later, when the electrode plate 110 passes through the roller 20 for laminating after being stacked, the second connection part 160 ) Since the pressure received by the roller 20 is small, the probability that the active material 11 falls off from the electrode plate 110 is small.

Figure 6 shows that an active material is coated on an electrode plate according to an embodiment of the present invention and then injected between rollers. Figure 7 illustrates coating an active material on an electrode plate and passing it through a roller according to an embodiment of the present invention.

Referring to FIGS. 6 and 7 , an insulating layer 12 may be further laminated on the top and bottom of the electrode plate 110 coated with the active material 11 on the top or bottom. The insulating layer 12 may be an insulating tape or a separator.

The electrode plate 110 is placed between a pair of rollers 20 for laminating. Therefore, when the electrode plate 110 is inserted between the rollers 20, the insulating layer 12 is compressed.

In addition, the active material 11 may be formed and exposed on the electrode plate 110 without a separate insulating layer 12 and placed between the rollers 20 to compress the active material 11.

When the electrode plate 110 is inserted between the rollers 20, the active material 11 may be pressed by the roller 20 and fall off. When the angle at the rightmost end of the first connection portion 150 of the electrode plate 110 located at the front end inputted into the roller 20 is an acute angle, the force applied to the electrode plate 110 becomes greater, so the active material The probability that (11) falls off from the electrode plate 110 increases. When the angle of the first connection part 150 of the electrode plate 110 according to the present invention is the second angle θ12, the angle of the first connection part 150 of the electrode plate 110 may be an obtuse angle. Therefore, when the electrode plate 110 is inserted between the rollers 20, the pressure applied to the electrode plate 110 decreases, thereby reducing the probability that the active material 11 will fall off.

Meanwhile, the second connection part 160 of the electrode plate 110 is the last part to escape from between the rollers 20 when it is inserted between the rollers 20, and therefore, compared to the first connection part 150, The pressure received by the roller 20 is small. Therefore, even if the angle of the second connection portion 160 corresponds to an acute angle, the probability that the active material 11 falls off from the electrode plate 110 is small.

Figure 8 is a plan view of an electrode sheet according to another embodiment of the present invention. Figure 9 is an enlarged view of part C of Figure 8. Figure 10 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention. Figure 11 is an enlarged view of part D of Figure 10. Figure 12 is an enlarged view of portion D' of Figure 10.

Referring to FIG. 8, the electrode sheet 200 according to another embodiment of the present invention may include an electrode plate 110, an electrode tab 120, and a cutting portion 230. Parts having the same structure and operation as those of the previous embodiment are indicated by the same reference numerals, and the following description will focus on the differences.

Referring to FIG. 9, the cutting part 230 is formed by cutting the length of the electrode sheet 200 on the upper side 100a and the lower side 100b of the electrode sheet 200 in order to separate the electrode plate 110. A pair is formed to be symmetrical based on direction. Cutting portions 230 formed to correspond to each other on the upper side 100a and the lower side 100b are formed at regular intervals along the longitudinal direction of the electrode sheet 200.

The cutting portion 230 may include a pair of first inclined portions 231, second inclined portions 232, and third inclined portions 233. The pair of first inclined portions 231, second inclined portions 232, and third inclined portions 233 may be formed to be symmetrical with respect to the direction (CL) in which the electrode sheet 200 is cut. . The first inclined portion 231 extends from the upper side 100a and the lower side 100b of the electrode sheet 200 to the inside of the electrode sheet 200 and is inclined in a direction facing each other. And the second inclined portion 232 extends from the end of the first inclined portion 231 to the inside of the electrode sheet 200 and is inclined in a direction facing each other. Additionally, the third inclined portion 233 extends from the end of the second inclined portion 232 to the outside of the electrode sheet 200 and is inclined in a direction facing each other. Accordingly, two notches consisting of the first inclined portion 231, the second inclined portion 232, and the third inclined portion 233 may be formed. Here, the first angle θ21 of the first inclined portion 231 may be an obtuse angle greater than 90° based on the direction CL in which the electrode sheet 200 is cut, and the electrode sheet 200 The second angle θ22 of the second inclined portion 232 based on the cutting direction CL may also be an obtuse angle greater than 90°. In addition, the third angle θ23 of the third inclined portion 233 based on the direction CL in which the electrode sheet 200 is cut may be an acute angle greater than 45°. Additionally, the first angle θ21 may be larger than the second angle θ22. Therefore, two notches consisting of a first inclined portion 231, a second inclined portion 232, and a third inclined portion 233 are formed in the cutting portion 230, so that the first connecting portion of the electrode plate 110 ( The probability that the angle at the rightmost end of 250) is an obtuse angle increases.

The portions cut by a cutting machine to separate the electrode plate 110 may be the second inclined portion 232 and the third inclined portion 233. That is, it can be cut within the width W2 formed by the second inclined portion 232 and the third inclined portion 233.

Referring to FIGS. 10, 11, and 12, the electrode plate 110 formed by cutting the electrode sheet 200 has an upper side (first side), a lower side (second side), a right side (third side), and a left side. It is formed in a square shape with a side (fourth side), and a first connection part 250 is formed at the connection part where the upper side, the lower side, and the right side meet, and a second connection part 250 is formed at the connection part where the upper side, the lower side, and the left side meet. A connection portion 260 is formed. Meanwhile, the electrode plate 110 can be separated by cutting the second inclined portion 231 of the cutting portion 230 along the line indicated by ③. If the second inclined portion 232 of the cutting portion 230 is cut along the line shown in ③ to separate the electrode plate 110, the first connecting portion 250 is located on the upper side (or lower side). It starts and continues to the right side, and is formed by being depressed by the inner reflection of the pole plate, and includes two inclined portions (the first inclined portion 231 and the second inclined portion 232) that form an obtuse angle with respect to the right side. do. And, depending on the shape of the cutting portion 230 of the electrode sheet 200 before cutting, the first inclined portion 231 starts from the upper or lower side and extends in the inner direction of the electrode plate 110 to be inclined. The second inclined portion 232 starts from the end of the first inclined portion 231 and is formed to be inclined toward the inside of the electrode plate 110. At this time, the first connection portion 250 of the separated electrode plate 110 is formed as a part of the first inclined portion 231 and the second inclined portion 232, and its angle may be a second angle θ22. In addition, even if the first inclined portion 231 is cut along the line shown as ④ due to an error in the cutting machine, the first connection portion 250 of the separated electrode plate 110 is a part of the first inclined portion 231. This angle may be the first angle (θ21). That is, when the first inclined portion 231 of the cutting portion 230 is cut along the line indicated by ④ to separate the electrode plate 110, the first connecting portion 250 is located on the upper side (or lower side). It starts from and continues to the right side, is formed by being depressed in the inner reflection of the pole plate, and includes one inclined portion (first inclined portion 231) forming an obtuse angle with respect to the right side. At this time, the angle at the rightmost end of the first connection portion 250 may be an obtuse angle. Therefore, when the electrode plates 110 pass through the rollers 20 for laminating after being stacked, the impact transmitted from the rollers 20 can be reduced.

Meanwhile, when the electrode plate 110 is separated by cutting the third inclined portion 233 of the cutting portion 230 along the line indicated by ⑤, the first connecting portion 250 is connected to the third inclined portion 233. ), the angle may be the third angle (θ23). That is, when the third inclined portion 233 of the cutting portion 230 is cut along the line shown as ⑤ to separate the electrode plate 110, the first connecting portion 250 is located on the upper side (or lower side). It starts from and continues to the right side, but is formed by being depressed by the inner reflection of the pole plate, and the inclined portion (the first inclined portion 231, the second inclined portion 232, and the third inclined portion) forming an obtuse angle with respect to the right side. (233)) and includes three. Also at this time, depending on the shape of the cutting portion 230 of the electrode sheet 200 before cutting, the first inclined portion 231 starts from the upper or lower side and extends in the inner direction of the electrode plate 110 to be inclined, The second inclined portion 232 is formed to be inclined toward the inside of the electrode plate 110 starting from the end of the first inclined portion 231, and the third inclined portion 233 is formed at the end of the second inclined portion 232. It starts and extends in the outer direction of the electrode plate 110. At this time, the angle at the rightmost end of the first connection portion 250 may be an acute angle. Even if the first connection part 250 further includes a part of the third inclined part 233 and the angle at its rightmost end is an acute angle, the size of the angle may be 45° or more. However, since the first connection portion 250 further includes a third inclined portion 233 and its size is greater than 45° even if the angle is an acute angle, the pressure applied to the electrode assembly by the roller 20 Since is not large, the probability of the active material 11 falling off is not high.

In addition, the second connection portion 260 of the separated electrode plate 110 includes not only the first inclined portion 231, the second inclined portion 232, and the third inclined portion 233, but also the third inclined portion ( 233) and a portion of the other third inclined portion 233, the fourth angle θ24 of the second connection portion 260 may be an acute angle. However, even if the angle of the second connection part 260 is an acute angle, as described above, when the electrode plate 110 passes through the roller 20 for laminating after being stacked, the second connection part 260 is connected to the roller ( Since the pressure received by 20) is small, the probability that the active material 11 falls off from the electrode plate 110 is small.

Accordingly, the cutting portion 230 further includes the third inclined portion 233 to form two notches, so that when the cutting portion 230 is cut, the first connecting portion 250 of the electrode plate 110 The probability that the angle at the rightmost end of is an obtuse angle may be higher than when a single notch is formed.

Figure 13 is a plan view of an electrode sheet according to another embodiment of the present invention. Figure 14 is an enlarged view of part E of Figure 13. Figure 15 is an enlarged view of part F of Figure 13. Figure 16 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention. Figure 17 is an enlarged view of part G of Figure 16. Figure 18 is an enlarged view of part G' of Figure 16. Figure 19 is an enlarged view of portion H of Figure 16. Figure 20 is an enlarged view of portion H' of Figure 16.

Referring to FIG. 13, the electrode sheet 300 according to another embodiment of the present invention may include an electrode plate 110, an electrode tab 120, a first cutting part 230, and a second cutting part 340. You can. Parts having the same structure and operation as those of the previous embodiment are indicated by the same reference numerals, and the following description will focus on the differences.

Referring to FIGS. 13, 14, and 15, the second cutting part 340 is formed on the lower side 300b of the electrode sheet 300 in order to separate the electrode plate 110. 230) and is formed at a symmetrical position based on the longitudinal direction of the electrode sheet 300. Second cutting parts 340 formed on the lower side 300b to correspond to the first cutting parts 230 are formed at regular intervals along the longitudinal direction of the electrode sheet 200.

The lower part 300b consists of a parallel part 301b parallel to the upper side 100a and a curved part 302b extending from the parallel part 301b to the inside of the electrode sheet 300. Accordingly, the probability that the angle at the rightmost end of the third connection portion 370 of the electrode plate 110 is an obtuse angle increases.

The second cutting part 340 may include a pair of inclined parts 341. The pair of inclined portions 341 may be formed to be symmetrical with respect to the direction CL in which the electrode sheet 300 is cut. The inclined portion 341 extends from the curved portion 302b of the lower side 300b of the electrode sheet 300 to the inside of the electrode sheet 300 and is inclined in a direction facing each other. That is, based on the direction CL in which the electrode sheet 300 is cut, the fifth angle θ35 of the inclined portion 341 may be an obtuse angle greater than 90°. Accordingly, one notch consisting of the inclined portion 341 may be formed in the second cutting portion 340.

The parts cut by the cutting machine to separate the electrode plate 110 are the second inclined portion 232 and third inclined portion 233 of the first cutting portion 230 and the second cutting portion 340. It may be the inclined portion 341 of . That is, within the width W3 formed by the second inclined portion 232 and third inclined portion 233 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340. Can be cut.

16 to 20, the electrode plate 110 formed by cutting the electrode sheet 300 has an upper side (first side), a lower side (second side), a right side (third side), and a left side (second side). It is formed in a square shape with 4 sides, and has a first connection part 250 at the connection part where the upper side and the right side meet, a second connection part 260 at the connection part where the upper side and the left side meet, and a second connection part 260 at the connection part where the upper side and the right side meet. A third connection part 370 is formed in the connection part, and a fourth connection part 380 is formed in the connection part where the lower side and the left side meet. The electrode plate 110 can be separated by cutting the second inclined portion 232 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340 along the line indicated by ⑥. If the second inclined portion 232 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340 are cut along the line indicated by ⑥ to separate the electrode plate 110, , the first connection portion 250 starts from the upper side and continues to the right side, and is formed by being recessed in the inner reflection of the electrode plate, and an inclined portion (the first inclined portion 231 and the second inclined portion 231) forming an obtuse angle with respect to the right side. It includes two inclined portions 232, and the third connection portion 370 starts from the lower side and continues to the right side, but extends toward the inner side of the electrode plate and forms an obtuse angle with respect to the right side. ) will be included. And, depending on the shape of the first cutting part 230 and the second cutting part 340 of the electrode sheet 300 before cutting, the first inclined part 231 starts from the upper side and moves toward the inside of the electrode plate 110. It is formed to be extended and inclined, and the second inclined portion 232 starts from the end of the first inclined portion 231 and is formed to be inclined toward the inside of the electrode plate 110, and the inclined portion 341 is formed at the end of the curved portion of the lower side. It starts and is formed slanted toward the inner side of the electrode plate. Accordingly, the first connection portion 250 of the separated electrode plate 110 may be formed of a portion of the first inclined portion 231 and the second inclined portion 232 and may have the second angle θ22, and the third connecting portion may have the second angle θ22. 370 may be composed of an inclined portion 341 and may be a fifth angle θ35. Additionally, the first inclined portion 231 may be cut along the line indicated by ⑦ due to errors in the cutting machine. If the first inclined portion 231 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340 are cut along the line indicated by ⑦ to separate the electrode plate 110, , the first connection part 250 starts from the upper side and continues to the right side, and is formed by being depressed in the inner reflection of the electrode plate, and has an inclined portion (first inclined portion 231) forming an obtuse angle with respect to the right side. The third connection portion 370 starts from the lower side and continues to the right side, and includes an inclined portion 341 that extends toward the inner side of the electrode plate and forms an obtuse angle with respect to the right side. Even in this case, the first connection portion 250 of the individually mounted electrode plate 110 may be formed as a part of the first inclined portion 231 and have a first angle θ21, and the third connection portion 370 may be formed as a part of the first inclined portion 231. It may be made up of a portion of the curved portion 302b of the lower portion 300b and have a rounded shape. That is, the angle at the rightmost end of the first connection part 250 and the third connection part 370 may be an obtuse angle. Therefore, when the electrode plates 110 pass through the rollers 20 for laminating after being stacked, the impact transmitted from the rollers 20 can be reduced.

When the third inclined portion 233 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340 are cut along the line indicated by ⑧ to separate the electrode plate 110, The first connection part 250 starts from the upper side and continues to the right side, and is formed by being recessed in the inner reflection of the electrode plate, and an inclined part (first inclined part 231, second inclined part 231) forming an obtuse angle with respect to the right side. It includes three parts (232) and a third inclined part (233), and the third connection part (370) starts from the lower side and continues to the right side, but extends toward the inner side of the electrode plate and extends to the right side. It includes an inclined portion 341 forming an obtuse angle. And, depending on the shape of the first cutting part 230 and the second cutting part 340 of the electrode sheet 300 before cutting, the first inclined part 231 starts from the upper side and moves toward the inside of the electrode plate 110. It is formed to be extended and inclined, and the second inclined portion 232 is formed to be inclined starting from the end of the first inclined portion 231 toward the inside of the electrode plate 110, and the third inclined portion 233 is the second inclined portion. Starting from the end of 232, it is formed to be inclined in the outer direction of the electrode plate 110, and the inclined portion 341 is formed to be inclined in the inner direction of the electrode plate, starting from the end of the curved portion of the lower side. If the electrode plate 110 is separated by cutting the third inclined portion 233 of the first cutting portion 230 and the inclined portion 341 of the second cutting portion 340 along the line indicated by ⑧, The first connection portion 250 may further include a portion of the third inclined portion 233 and its angle may be a third angle θ23. That is, the angle at the rightmost end of the first connection portion 250 may be an acute angle. Even if the first connection part 250 further includes a part of the third inclined part 233 and the angle is an acute angle, the size of the angle may be 45° or more. However, since the first connection portion 250 further includes a third inclined portion 233 and its size is greater than 45° even if the angle is an acute angle, the pressure applied to the electrode assembly by the roller 20 Since is not large, the probability of the active material 11 falling off is not high.

Meanwhile, the second connection portion 260 of the separated electrode plate 110 includes not only the first inclined portion 231, the second inclined portion 232, and the third inclined portion 233, but also the third inclined portion ( 233) and a portion of the other third inclined portion 233, the fourth angle θ24 of the second connection portion 260 may be an acute angle. In addition, the fourth connection portion 380 of the separated electrode plate 110 further includes not only the inclined portion 341 but also a portion of another inclined portion 341 paired with the inclined portion 341, The sixth angle θ36 of the fourth connection portion 380 may be an acute angle. However, even if the angle of the second connection part 260 and the fourth connection part 380 is an acute angle, as described above, when the electrode plate 110 passes through the roller 20 for laminating after being stacked, the second connection part Since the pressure applied to 260 and the fourth connection portion 380 by the roller 20 is small, the probability that the active material 11 falls off from the electrode plate 110 is small.

Therefore, the first cutting part 230 and the second cutting part 340 can be formed in different shapes, and the second cutting part 340 is formed by extending from the curved part of the lower part 300b. , the probability that the second connection portion 360 of the electrode plate 110 forms an obtuse angle may be higher.

Meanwhile, the first cutting part 230 and the second cutting part 340 may be formed differently from each other, not only in the above shape but also in shapes of other embodiments.

Figure 21 is a plan view of an electrode sheet according to another embodiment of the present invention. Figure 22 is an enlarged view of part G of Figure 21. Figure 23 is a plan view of an electrode plate formed by cutting an electrode sheet according to another embodiment of the present invention. Figure 24 is an enlarged view of part H of Figure 23. Figure 25 is an enlarged view of portion H' of Figure 23.

Referring to FIG. 21, the electrode sheet 400 according to another embodiment of the present invention may include an electrode plate 110, an electrode tab 120, and a cutting portion 430. Parts having the same structure and operation as those of the previous embodiment are indicated by the same reference numerals, and the following description will focus on the differences.

Referring to FIG. 22, the cutting part 430 is formed by cutting the length of the electrode sheet 400 on the upper side (100a) and the lower side (100b) of the electrode sheet 400 in order to separate the electrode plate 110. A pair is formed so that it is symmetrical based on the direction. Cutting portions 430 formed to correspond to each other on the upper side 100a and lower side 100b are formed at regular intervals along the longitudinal direction of the electrode sheet 400.

The cutting portion 430 may include a first inclined portion 431, a second inclined portion 432, and a third inclined portion 433. The first inclined portion 431 extends from the upper side 100a and the lower side 100b of the electrode sheet 400 to the inside of the electrode sheet 400 and is formed to be inclined. And the second inclined portion 432 extends from the end of the first inclined portion 431 to the inside of the electrode sheet 400 and is formed to be inclined. In addition, the third inclined portion 433 extends from the upper side 100a and the lower side 100b of the electrode sheet 400 to the inside of the electrode sheet 400, and forms the first inclined portion 431 and It is formed to be inclined in a direction facing the second inclined portion 432. That is, the first angle θ41 of the first inclined portion 431 may be an obtuse angle greater than 90° based on the direction CL in which the electrode sheet 400 is cut, and the electrode sheet 400 The second angle θ42 of the second inclined portion 432 based on the cutting direction CL may also be an obtuse angle greater than 90°. Additionally, the third angle θ43 of the third inclined portion 433 may be an acute angle based on the direction CL in which the electrode sheet 400 is cut. Additionally, the first angle θ41 may be larger than the second angle θ42. Accordingly, the cutting portion 430 may be formed with one notch consisting of the first inclined portion 431, the second inclined portion 432, and the third inclined portion 433, but the cutting portion 430 is formed to be asymmetrical with respect to the center of the cutting portion 430, so if cutting is made within the width W4 of the second inclined portion 432, the first connecting portion 450 of the electrode plate 110 The angle at the rightmost edge may be an obtuse angle. Meanwhile, the center of the cutting portion 430 refers to the center based on the width of the first inclined portion 431, the second inclined portion 432, and the third inclined portion 433.

The portion cut by a cutting machine to separate the electrode plate 110 may be the second inclined portion 432. That is, it can be cut within the width W4 formed by the second inclined portion 432.

Referring to FIGS. 23, 24, and 25, the electrode plate 110 formed by cutting the electrode sheet 400 has an upper side (first side), a lower side (second side), a right side (third side), and a left side. It is formed in a square shape with a side (fourth side), and a first connection part 450 is formed at the connection part where the upper side, lower side, and right side meet, and a first connection part 450 is formed at the connection part where the upper side, lower side, and the left side meet. 2 Connection portion 460 is formed. The electrode plate 110 can be separated by cutting the second inclined portion 432 of the cutting portion 430 along the line indicated by ⑨. If the second inclined portion 432 of the cutting portion 430 is cut along the line shown by ⑨ to separate the electrode plate 110, the first connecting portion 450 starts from the upper side and moves to the right side. It is connected, and is formed by recessing the inner side of the electrode plate, and includes two inclined portions (a first inclined portion 431 and a second inclined portion 432) forming an obtuse angle with respect to the right side. And, depending on the shape of the cutting portion 430 of the electrode sheet 400 before cutting, the first inclined portion 431 starts from the upper or lower side and extends in the inner direction of the electrode plate 110 to be inclined. The second inclined portion 432 starts from the end of the first inclined portion 431 and is formed to be inclined toward the inside of the electrode plate 110. Accordingly, the first connection portion 450 of the separated electrode plate 110 may be formed as a part of the first inclined portion 431 and the second inclined portion 432 and its angle may be the second angle θ42. Also, due to the error of the cutting machine, the first inclined portion 431 may be cut along the line shown as ⑩. If the first inclined portion 431 of the cutting portion 430 is cut along the line indicated by ⑩ to separate the electrode plate 110, the first connecting portion 450 starts from the upper side and moves to the right side. It is connected, but is formed by being depressed into the inner reflection of the electrode plate, and includes one inclined portion (first inclined portion 431) forming an obtuse angle with respect to the right side. Even in this case, it may be formed as part of the first connection portion 450 of the separated electrode plate 110 and its angle may be the first angle θ41. That is, the angle at the rightmost end of the first connection portion 45 may be an obtuse angle. Therefore, when the electrode plates 110 pass through the rollers 20 for laminating after being stacked, the impact transmitted from the rollers 20 can be reduced.

Meanwhile, due to an error in the cutting machine, the electrode plate 110 may be separated by cutting the third inclined portion 433 along the line indicated by ⑪. When the third inclined portion 433 of the cutting portion 430 is cut along the line indicated by ⑪ to separate the electrode plate 110, the first connecting portion 450 starts from the upper side and moves to the right side. The slanted portions (the first slanted portion 431, the second slanted portion 432, and the third slanted portion 433) that are connected and formed by being depressed in the inner reflection of the pole plate and form an obtuse angle with respect to the right side are 3. Includes dogs. Also at this time, depending on the shape of the cutting portion 430 of the electrode sheet 400 before cutting, the first inclined portion 431 starts from the upper or lower side and extends in the inner direction of the electrode plate 110 to be inclined, The second inclined portion 432 is formed to be inclined toward the inside of the electrode plate 110 starting from the end of the first inclined portion 431, and the third inclined portion 433 is formed at the end of the second inclined portion 432. It starts and extends in the outer direction of the electrode plate 110. When the third inclined portion 433 is cut along the line indicated by ⑪, the first connecting portion 450 further includes a portion of the third inclined portion 433 and its angle is the third angle θ43. ) can be. That is, the angle at the rightmost end of the first connection part 450 may be an acute angle. However, if the ratio of the width formed by the first inclined portion 431 and the second inclined portion 432 is increased to the width formed by the cutting portion 430, the maximum of the first connecting portion 450 of the electrode plate 110 is increased. The probability that the angle at the right end is an obtuse angle may increase.

In addition, the second connection portion 460 of the separated electrode plate 110 further includes not only the third inclined portion 433 but also a portion of the second inclined portion 432, so that the second connecting portion 460 The fourth angle θ44 may be an acute angle. However, even if the fourth angle θ44 of the second connection portion 46 is an acute angle, as described above, when the electrode plate 110 passes through the roller 20 for laminating after being stacked, the second connection portion 460 ) Since the pressure received by the roller 20 is small, the probability that the active material 11 falls off from the electrode plate 110 is small.

Accordingly, since the first inclined portion 431, the second inclined portion 432, and the third inclined portion 433 of the cutting portion 460 are formed asymmetrically, when the cutting portion 460 is cut, the first inclined portion 431, the second inclined portion 432, and the third inclined portion 433 are formed asymmetrically. The probability that the angle of the rightmost end of the first connection portion 460 of the electrode plate 110 is an obtuse angle may be higher than when it is formed symmetrically.

What has been described above is only one example for carrying out the electrode sheet according to the present invention, the electrode plate produced by cutting the electrode sheet, the electrode assembly formed by laminating the electrode plates, and the method of manufacturing the electrode plate, and the present invention is not limited to the above-described embodiments, and as claimed in the following patent claims, to the extent that anyone skilled in the art can make various changes without departing from the gist of the invention. It may be said that there is a technical spirit of the present invention.

11: active material 12: insulating layer
20: Roller 100, 200, 300, 400: Electrode sheet
100a: upper side 100b, 300b: lower side
110: electrode plate 120: electrode tab
130,230,340,430: Cutting part 150,250,450: First connection part
160,260,460: 2nd connection 370: 3rd connection
380: Fourth connection

Claims (10)

An electrode active material is applied on one or both sides, a first side, a second side opposite the first side, a third side perpendicular to the first side and the second side, and a fourth side opposite the third side. In a secondary battery including an electrode plate with sides,
It includes one or more connecting parts formed at a connecting part between the first side and the third side or the fourth side, or a connecting part between the second side and the third side or the fourth side, and the connecting part is located on the first side. It starts and continues to the third side or the fourth side, or starts from the second side and continues to the third or fourth side, and is formed by being depressed in the inner direction of the electrode plate, and the third side or the fourth side is formed. Contains two or more inclined parts forming an obtuse angle based on the four sides,
The inclined part
a first inclined portion starting from at least one of the first side and the second side and extending toward the inside of the electrode plate to be inclined; and
Starting from the end of the first inclined portion, the second inclined portion extends toward the inner side of the electrode plate and is formed to be inclined,
A secondary battery in which the first angle formed by the first inclined portion is greater than the second angle formed by the second inclined portion with respect to the third side or the fourth side. delete delete According to claim 1,
The inclined part
The secondary battery further includes a third inclined portion that forms an acute angle with respect to the third side or the fourth side and is inclined starting from an end of the second inclined portion and extending in an outer direction of the electrode plate. According to claim 4,
A secondary battery in which the angle formed by the third inclined portion with respect to the third side or the fourth side is 45° or more. According to claim 1,
The connection portion includes a first connection portion formed on the first side and a second connection portion formed on the second side,
The second side of the electrode plate includes a parallel portion parallel to the first side and a curved portion starting from an end of the parallel portion and extending in the inner direction of the electrode plate, and the inclined portion of the second connection formed on the second side is A secondary battery formed by starting from the end of the curved portion and extending in the inner direction of the electrode plate. According to claim 6,
A secondary battery wherein the inclined portion of the second connection portion formed on the second side of the electrode plate includes an inclined portion that starts from the second side and extends in an inner direction of the electrode plate. According to claim 7,
The inclined portion of the first connection formed on the first side of the electrode plate
a first inclined portion that starts from the first side and extends toward the inside of the electrode plate and is formed to be inclined; and
Starting from the end of the first inclined portion, the second inclined portion extends toward the inside of the electrode plate and is formed to be inclined,
The secondary battery further includes a third inclined portion that forms an acute angle with respect to the third side or the fourth side and is inclined starting from an end of the second inclined portion and extending in an outer direction of the electrode plate. According to claim 1,
The secondary battery further includes at least one inclined portion forming an acute angle with respect to the third or fourth side. According to clause 9,
The inclined part
a first inclined portion starting from at least one of the first side and the second side and extending toward the inside of the electrode plate to be inclined;
a second inclined portion starting from the end of the first inclined portion and extending toward the inside of the electrode plate to be inclined; and
A secondary battery including a third inclined portion that starts from at least one of the first side and the second side, extends in an inner direction of the electrode plate, and is inclined in a direction facing the first inclined portion and the second inclined portion.