Title of Invention: Secondary battery, method for manufacturing the secondary battery, and battery pack comprising the secondary battery
technical field
[One]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0102027 dated August 20, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[2]
The present invention relates to a secondary battery, a method for manufacturing the secondary battery, and a battery pack including the secondary battery, a secondary battery having a large capacity while maintaining a curved shape at the time of manufacture, a manufacturing method of the secondary battery, and the secondary battery It is about a battery pack containing
background
[3]
Secondary batteries capable of repetitive charging and discharging generally have a regular shape such as a rectangular parallelepiped or a cylinder, but as the shapes of electronic devices become diversified and the need to maximize the utility of the internal space of electronic devices increases, electronic devices The shape of the secondary battery mounted therein is also required to be atypical unlike the prior art.
[4]
As an example of a secondary battery having an atypical shape, a secondary battery having a curved surface may be mentioned. According to the prior art, after manufacturing a secondary battery, one or both surfaces of the secondary battery are pressed through a jig having a curved surface, thereby manufacturing a secondary battery having a curved surface.
[5]
However, according to the prior art, even when a secondary battery having a curved surface is manufactured, there is a problem in that the curved surface cannot be maintained and the curved surface is stretched due to stress or restoring force existing inside the secondary battery. In particular, as the radius of curvature of the curved surface decreased, the length of the secondary battery increased, and the thickness of the secondary battery increased, the tendency of the curved surface formed in the secondary battery to be stretched again increased. This acted as an obstacle in manufacturing a secondary battery having a shape with a higher degree of freedom.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[6]
Accordingly, an object of the present invention is to solve a problem in which a curved surface formed in a secondary battery is stretched by stress or restoring force inside the secondary battery.
[7]
In addition, another problem to be solved by the present invention is to manufacture a secondary battery having a shape having a higher degree of freedom than in the related art.
means of solving the problem
[8]
According to a first aspect of the present invention for achieving the above object, the electrode assembly having a structure in which a plurality of electrodes and a plurality of separators are alternately disposed; including, wherein the electrode includes: a body portion forming a body of the electrode; and an electrode tab protruding from the body in one direction. Including, wherein the electrode has a sheet structure, the upper and lower surfaces of the body portion of the electrode are respectively formed as flat surfaces, and a planar area and a curved area are formed together on the circumferential surface of the body of the plurality of electrodes, respectively, and the The plurality of electrodes are stacked so that the planar region and the curved region formed on the circumferential surface of the body of the plurality of electrodes are adjacent to regions having shapes corresponding to each other, thereby forming a thickness t of the electrode assembly. A secondary battery in which a curved surface is formed on some of the side surfaces of the electrode assembly is provided.
[9]
The electrode assembly may include: a first basic unit including a first electrode and a separator; a second basic unit including a second electrode and a separator; and a third electrode, and a third basic unit provided between the first basic unit and the second basic unit, wherein the first basic unit includes a plurality of the electrodes formed on the plurality of first electrodes. Tabs are bonded to each other to form a first electrode tab bundle, and to the second basic unit, a plurality of electrode tabs formed on a plurality of second electrodes are bonded to each other to form a second electrode tab bundle; An area of ​​an electrode tab formed on the electrode is larger than an area of ​​an electrode tab formed on the first electrode and an area of ​​an electrode tab formed on the second electrode, and one surface of the electrode tab formed on the third electrode is the first electrode tab bundle. The other surface may be bonded to the bundle of the second electrode tabs while being bonded to the .
[10]
An area A1 in which the electrode tab formed on the third electrode is bonded to the first electrode tab bundle and an area A2 in which the second electrode tab bundle is bonded include the electrode tab formed on the third electrode in the third electrode tab bundle. They may be spaced apart from each other in a direction intersecting with a direction in which they protrude from the body of the electrode.
[11]
Each of the electrode tabs formed on the electrode may be formed on the planar region formed on a circumferential surface of the body portion of the electrode.
[12]
Each of the electrode tabs formed on the electrode may be formed in the curved area formed on the circumferential surface of the body portion of the electrode.
[13]
The first basic unit further includes a fourth electrode having a polarity different from that of the first electrode, and the second basic unit further includes a fifth electrode having a polarity different from that of the second electrode; The third basic unit further includes a sixth electrode having a polarity different from that of the third electrode, and to the first basic unit, a plurality of electrode tabs formed on a plurality of the fourth electrodes are bonded to each other to form a fourth electrode tab A bundle is formed, and in the second basic unit, a plurality of the electrode tabs formed on the plurality of fifth electrodes are joined to each other to form a fifth electrode tab bundle, and the area of ​​the electrode tabs formed on the sixth electrode is, An area of ​​an electrode tab formed on the fourth electrode and an area of ​​an electrode tab formed on the fifth electrode are larger than an area of ​​the electrode tab formed on the sixth electrode, and one surface of the electrode tab formed on the sixth electrode is bonded to the bundle of the fourth electrode tabs, and the other surface is the fifth electrode An area A4 bonded to the tab bundle and an electrode tab formed on the sixth electrode bonded to the fourth electrode tab bundle and an area A5 bonded to the fifth electrode tab bundle are formed on the sixth electrode The electrode tabs may be spaced apart from each other in a direction intersecting a direction in which they protrude from the body portion of the sixth electrode.
[14]
According to a second aspect of the present invention for achieving the above object, a preparation step of preparing a plurality of electrodes including a plurality of separators, a body portion and an electrode tab protruding in one direction from the body portion, and having a sheet structure; and disposing the electrode and the separator to have a structure in which the electrode and the separator are alternately disposed. and, in the disposing step, by arranging the electrode such that regions having a shape corresponding to each other and a planar region formed on a circumferential surface of the body portion of the electrode having a sheet structure are disposed adjacent to each other, the electrode and the There is provided a method of manufacturing a secondary battery in which a curved surface is formed on some of the side surfaces of the electrode assembly forming the thickness t of the electrode assembly formed by alternately disposing separators.
[15]
Each of the electrode tabs formed on the electrode provided in the preparation step may be formed in the planar region formed on the circumferential surface of the body portion of the electrode.
[16]
Each of the electrode tabs formed on the electrode provided in the preparation step may be formed on the curved region formed on the circumferential surface of the body portion of the electrode.
[17]
The preparing may include preparing a first basic unit including a first electrode and a separator, a second basic unit including a second electrode and a separator, and a third basic unit including a third electrode; wherein the disposing step comprises: disposing the third basic unit between the first basic unit and the second basic unit; may include
[18]
forming a first electrode tab bundle by bonding a plurality of electrode tabs of the first electrodes to the first basic unit to form a first electrode tab bundle; forming a second electrode tab bundle by bonding a plurality of electrode tabs of the second electrodes to the second basic unit to form a second electrode tab bundle; and a third electrode tab bonding step of bonding one surface of the electrode tab of the third electrode to the first electrode tab bundle and bonding the other surface to the second electrode tab bundle; and an area of ​​the electrode tab formed on the third electrode may be larger than an area of ​​the electrode tab formed on the first electrode and an area of ​​the electrode tab formed on the second electrode.
[19]
After the third electrode tab bonding step, the region A1 in which the electrode tab formed on the third electrode is bonded to the first electrode tab bundle and the region A2 in which the second electrode tab bundle is bonded to the second electrode tab bundle The electrode tabs formed on the third electrode may be spaced apart from each other in a direction intersecting a direction in which they protrude from the body of the third electrode.
[20]
The first basic unit further includes a fourth electrode having a polarity different from that of the first electrode, the second basic unit further includes a fifth electrode having a polarity different from that of the second electrode, and the third The basic unit further includes a sixth electrode having a polarity different from that of the third electrode, and a fourth electrode tab is formed by bonding a plurality of electrode tabs of the fourth electrode to the first basic unit to form a fourth electrode tab bundle. electrode tab bundle forming step; a fifth electrode tab bundle forming step of forming a fifth electrode tab bundle by bonding the plurality of fifth electrode electrode tabs to the second basic unit; and a sixth electrode tab bonding step of bonding one surface of the electrode tab of the sixth electrode to the fourth electrode tab bundle and bonding the other surface to the fifth electrode tab bundle; may further include.
[21]
According to a third aspect of the present invention for achieving the above object, there is provided a battery pack including the secondary battery.
Effects of the Invention
[22]
According to the present invention, it is possible to solve the problem that the curved surface formed in the secondary battery is stretched by the internal stress or restoring force of the secondary battery.
[23]
In addition, according to the present invention, it is possible to manufacture a secondary battery having a shape with a higher degree of freedom than in the related art.
Brief description of the drawing
[24]
1 is a perspective view illustrating the structure of a first electrode and a fourth electrode constituting a first basic unit according to a first embodiment of the present invention.
[25]
2 is a perspective view illustrating the structures of a second electrode and a fifth electrode constituting the second basic unit according to the first embodiment of the present invention.
[26]
3 is a perspective view illustrating structures of a third electrode and a sixth electrode constituting the third basic unit according to the first embodiment of the present invention.
[27]
4 is a perspective view illustrating an electrode assembly of a secondary battery according to a first embodiment of the present invention.
[28]
5 is a cross-sectional view illustrating a state in which first to third electrode tabs are joined in the secondary battery according to the present invention.
[29]
6 is a cross-sectional view illustrating a state in which fourth to sixth electrode tabs are joined in the secondary battery according to the present invention.
[30]
7 is a perspective view illustrating the structures of the first electrode and the fourth electrode constituting the first basic unit according to the second embodiment of the present invention.
[31]
8 is a perspective view illustrating structures of a second electrode and a fifth electrode constituting a second basic unit according to a second embodiment of the present invention.
[32]
9 is a perspective view illustrating structures of a third electrode and a sixth electrode constituting a third basic unit according to a second embodiment of the present invention.
[33]
10 is a perspective view illustrating an electrode assembly of a secondary battery according to a second embodiment of the present invention.
[34]
11 is a perspective view showing the structures of the first electrode and the fourth electrode constituting the first basic unit according to the third embodiment of the present invention.
[35]
12 is a perspective view illustrating structures of a second electrode and a fifth electrode constituting a second basic unit according to a third embodiment of the present invention.
[36]
13 is a perspective view illustrating structures of a third electrode and a sixth electrode constituting a third basic unit according to a third embodiment of the present invention.
[37]
14 is a perspective view illustrating an electrode assembly of a secondary battery according to a third embodiment of the present invention.
Modes for carrying out the invention
[38]
Hereinafter, the structure of the secondary battery according to the present invention will be described with reference to the drawings.
[39]
[40]
secondary battery
[41]
1 is a perspective view showing the structures of a first electrode and a fourth electrode constituting a first basic unit according to a first embodiment of the present invention, and FIG. 2 is a second basic unit according to a first embodiment of the present invention. It is a perspective view showing the structure of the second electrode and the fifth electrode constituting the . 3 is a perspective view showing the structures of the third electrode and the sixth electrode constituting the third basic unit according to the first embodiment of the present invention, and FIG. 4 is an electrode of a secondary battery according to the first embodiment of the present invention. It is a perspective view showing the assembly.
[42]
The secondary battery according to the present invention may include an electrode assembly 10 . The electrode assembly 10 may have a structure in which a plurality of electrodes and a plurality of separators (not shown) are alternately disposed. 4 , the electrode assembly 10 may form a predetermined thickness t in a direction in which a plurality of electrodes and a plurality of separators are alternately disposed.
[43]
At this time, as shown in Figures 1 to 3, the electrodes (110, 120, 210, 220, 310, 320) are body parts (110a, 120a, 210a, 220a, 310a, 320a) forming the body of the electrode and It may include electrode tabs 110b, 120b, 210b, 220b, 310b, and 320b protruding from the body in one direction. The electrode according to the present invention may include a first electrode 110 , a second electrode 210 , a third electrode 310 , a fourth electrode 120 , a fifth electrode 220 , and a sixth electrode 320 . can In addition, the first electrode 110 includes a first body portion 110a and a first electrode tab 110b, and the second electrode 210 includes a second body portion 210a, a second electrode tab 210b, and a third The electrode 310 includes a third body portion 310a and a third electrode tab 310b, and the fourth electrode 120 includes a fourth body portion 120a, a fourth electrode tab 120b, and a fifth electrode 220. A fifth body portion 220a and a fifth electrode tab 220b, and the sixth electrode tab 330 may include a sixth body portion 330a and a sixth electrode tab 330b, respectively.
[44]
The electrode according to the present invention may have a sheet structure. The 'sheet structure' may refer to a structure in which the thickness of the side surface is significantly smaller than the size of the upper surface and the lower surface.
[45]
1 to 4, according to the present invention, the body parts 110a, 120a, 210a, 220a, 310a, 320a of the electrodes 110, 120, 210, 220, 310, 320 of the electrode assembly 10. ), the upper and lower surfaces may be formed as flat surfaces, respectively. In this case, the flat surface may be understood as a concept opposite to the curved surface.
[46]
In addition, as shown in FIGS. 1 to 3 , according to the present invention, the circumferential surface of the body parts 110a, 120a, 210a, 220a, 310a, and 320a of the electrodes 110, 120, 210, 220, 310, 320 has A planar region, which is a region each having a flat surface, and a curved region, which is a region having a curved surface, may be formed together. 1 to 3, a concavely indented curved area is formed on the left circumferential surface of the circumferential surface of the body of the electrode, a convexly protruding curved area is formed on the right circumferential surface, and a planar area is formed on the upper and lower circumferential surfaces, respectively. The formed case is shown.
[47]
On the other hand, in the electrode assembly 10 according to the present invention, the flat area and the curved area formed on the circumferential surfaces of the body parts 110a, 120a, 210a, 220a, 310a, 320a are adjacent to each other and have a shape corresponding to each other. The electrodes 110 , 120 , 210 , 220 , 310 , and 320 may have a stacked structure. That is, referring to FIGS. 1 to 4 , in the electrode assembly 10 , the plurality of electrodes are arranged adjacent to each other among the curved regions of the circumferential surface of the electrode, and the concave curved regions of the peripheral surface of the electrode are disposed adjacent to each other. Among the curved areas, convexly protruding curved areas may be disposed adjacent to each other.
[48]
Therefore, according to the present invention, a curved surface having a shape corresponding to the curved area formed on the electrode is formed on at least a portion of the side surface of the electrode assembly forming the thickness t of the electrode assembly 10, and among the side surfaces of the electrode assembly In another portion, a plane having a shape corresponding to a plane region formed in the electrode may be formed.
[49]
Therefore, according to the present invention, a secondary battery having a curved surface can be manufactured without a separate pressing process for forming the curved surface.
[50]
In particular, in the case of a secondary battery having a curved surface according to the prior art, a flat electrode assembly or secondary battery is first manufactured, and then some of the flat surfaces of the secondary battery are pressed with a jig having a curved surface to form a curved surface in the secondary battery. Thus, the surfaces of adjacent electrodes facing each other in the electrode assembly are also formed as curved surfaces. However, in this case, since the curved surface of the electrode is artificially formed by pressing, a restoring force acting in the direction in which the curved surface is unfolded again is generated in the electrode assembly. Accordingly, in the case of a secondary battery having a curved surface manufactured according to the prior art, the curved surface is spread over time. This may be understood as an increase in the radius of curvature of the curved surface formed in the secondary battery over time.
[51]
However, in the secondary battery having a curved surface manufactured according to the present invention, since the surfaces of adjacent electrodes facing each other are formed as a flat surface, a restoring force acting in the direction in which the curved surface is unfolded again in the electrode assembly does not occur. Accordingly, in the case of manufacturing the secondary battery having a curved surface according to the present invention, the problem of the curved surface being spread does not occur even if time passes. That is, according to the present invention, even if time passes, the radius of curvature of the curved surface formed in the secondary battery may be maintained as it is.
[52]
Meanwhile, the electrode assembly 10 according to the present invention may include a plurality of basic units. That is, as shown in FIG. 4 , the electrode assembly 10 includes a first basic unit 100 , a second basic unit 200 , and a third basic unit provided between the first basic unit and the second basic unit ( 300) may be included. That is, the electrode assembly 10 may have a structure in which the first basic unit 100 , the third basic unit 300 , and the second basic unit 200 are alternately stacked from the bottom. Meanwhile, referring to FIGS. 1 to 4 , the first basic unit 100 may include a first electrode 110 , a fourth electrode 120 , and a separator, and the second basic unit 200 may include a second The electrode 210 , the fifth electrode 220 , and the separator may be included, and the third basic unit 300 may include the third electrode 310 , the sixth electrode 320 , and the separator. In this case, the first electrode 110 and the fourth electrode 120 may have different polarities, the second electrode 210 and the fifth electrode 220 may have different polarities, and the third electrode ( The 310 and the sixth electrode 320 may have different polarities.
[53]
Meanwhile, referring to FIG. 4 , in the electrode assembly 10 of a secondary battery according to the present invention, electrode tabs formed on a plurality of electrodes are respectively bonded to the first basic unit body 100 and the second basic unit body 200 to form an electrode. A tab bundle may be formed.
[54]
That is, in the first basic unit 100 , a plurality of first electrode tabs formed on a plurality of first electrodes may be bonded to each other to form a first electrode tab bundle P1 , and a plurality of first electrode tabs formed on a plurality of fourth electrodes may be formed. A fourth electrode tab bundle P4 may be formed by bonding the fourth electrode tabs to each other.
[55]
In addition, in the second basic unit 200 , a plurality of second electrode tabs formed on a plurality of second electrodes may be bonded to each other to form a second electrode tab bundle P2 , and a plurality of second electrode tabs formed on a plurality of fifth electrodes may be formed. The fifth electrode tabs may be bonded to each other to form a fifth electrode tab bundle P5 . Each of the first electrode tab bundle P1 , the second electrode tab bundle P2 , the fourth electrode tab bundle P4 , and the fifth electrode tab bundle P5 may be formed by welding.
[56]
At this time, referring to FIGS. 3 and 4 , one surface (the lower surface of the third electrode tab with reference to FIG. 4 ) of the third electrode tab 310b formed on the third electrode 310 is the first electrode tab bundle P1 . ), the other surface of the third electrode tab 310b (a top surface of the third electrode tab with reference to FIG. 4 ) may be bonded to the second electrode tab bundle P2 .
[57]
In addition, one surface (a lower surface of the sixth electrode tab with reference to FIG. 4 ) of the sixth electrode tab 320b formed on the sixth electrode 320 is bonded to the fourth electrode tab bundle P4 , and the sixth electrode tab The other surface of the 320b (refer to FIG. 4 , the upper surface of the sixth electrode tab) may be bonded to the fifth electrode tab bundle P5.
[58]
Meanwhile, as shown in FIGS. 1 to 3 , the area of ​​the third electrode tab 310b formed on the third electrode 310 is the area of ​​the first electrode tab 110b formed on the first electrode 110 and The area of ​​the second electrode tab 210b formed on the second electrode 210 may be larger than that of the second electrode tab 210b. Similarly, the area of ​​the sixth electrode tab 320b formed on the sixth electrode 320 is the area of ​​the fourth electrode tab 120b formed on the fourth electrode 120 and the area of ​​the fourth electrode tab 120b formed on the fifth electrode 220 . It may be larger than the area of ​​the 5 electrode tab 220b.
[59]
5 is a cross-sectional view illustrating a state in which first to third electrode tabs are bonded in a secondary battery according to the present invention, and FIG. 6 is a state in which fourth to sixth electrode tabs are bonded in a secondary battery according to the present invention. It is one cross section.
[60]
As described above, the area of ​​the third electrode tab may be larger than that of the first electrode tab and the area of ​​the second electrode tab. Accordingly, as shown in FIG. 5 , a region A1 in which the third electrode tab 310b formed on the third electrode is bonded to the first electrode tab bundle P1 and the second electrode tab bundle P2 are bonded to each other. The areas A2 may be spaced apart from each other. That is, as shown in FIG. 5 , the regions A1 and A2 are in a direction (D) crossing the direction in which the third electrode tab 310b formed on the third electrode 310 protrudes from the third body 310a. ) may be spaced apart from each other.
[61]
According to the present invention, in the process of manufacturing the electrode assembly of the secondary battery, the third electrode tab 310b may be bonded to the first electrode tab bundle P1 and also to the second electrode tab bundle P2 . In this case, when the region A1 bonded to the first electrode tab bundle P1 and the region A2 bonded to the second electrode tab bundle P2 overlap each other in the third electrode tab 310b, the third In the electrode tab 310b, a portion belonging to the A1 region and at the same time belonging to the A2 region is present. In this case, since both the process of bonding the first electrode tab bundle P1 and the bonding of the second electrode tab bundle P2 are performed in the region belonging to the A1 region and the A2 region, the third electrode tab 310b durability may be greatly reduced. In particular, when the bonding between the third electrode tab 310b and the first electrode tab bundle P1 and the bonding between the third electrode tab 310b and the second electrode tab bundle P2 are made by welding, the A1 region A problem in that the third electrode tab is damaged or cut may occur in a region where the region A2 and the region A2 overlap (ie, a region where welding is performed twice in the third electrode tab).
[62]
Therefore, in order to solve the above problem, according to the present invention, the area A1 and the area A2 may be spaced apart from each other. Meanwhile, for the same reason as the above for the A1 region and A2 region, as shown in FIG. 6 , the sixth electrode tab 320b formed on the sixth electrode 320 is bonded to the fourth electrode tab bundle P4. The region A5 joined to the region A4 and the fifth electrode tab bundle P5 is also similar to the direction in which the sixth electrode tab 320b formed on the sixth electrode 320 protrudes from the sixth body portion 320a. They may be spaced apart from each other in an intersecting direction.
[63]
1 to 3 again, the electrode tabs 110b, 120b, 210b, 220b, 310b, and 320b formed on the electrodes 110, 120, 210, 220, 310, and 320 according to the present invention are the body of the electrode, respectively. It may protrude from the curved area formed on the peripheral surface of the part. For example, according to the first embodiment of the present invention, as shown in FIGS. 1 to 3 , the electrode tabs formed on the electrodes are in the concave recessed curved area among the curved areas formed on the circumferential surface of the body of the electrode, respectively. can be formed. Accordingly, according to the first embodiment of the present invention, in the electrode assembly of the secondary battery, the electrode tab or the electrode tab bundle is a concavely indented curved surface among the side surfaces of the electrode assembly forming the thickness (t, see FIG. 4 ) of the electrode assembly. may be formed in the region.
[64]
7 is a perspective view illustrating structures of a first electrode and a fourth electrode constituting a first basic unit according to a second embodiment of the present invention, and FIG. 8 is a second basic unit according to a second embodiment of the present invention. It is a perspective view showing the structure of the second electrode and the fifth electrode constituting the . 9 is a perspective view illustrating the structure of a third electrode and a sixth electrode constituting a first basic unit according to a third embodiment of the present invention, and FIG. 10 is an electrode of a secondary battery according to a second embodiment of the present invention. It is a perspective view showing the assembly.
[65]
According to the second embodiment of the present invention, the electrode tabs 110b, 120b, 210b, 220b, 310b, and 320b formed on the electrodes 110, 120, 210, 220, 310, 320 are respectively formed on the circumferential surface of the body of the electrode. It may be formed in the formed planar area. Therefore, according to the second embodiment of the present invention, in the electrode assembly of the secondary battery, the electrode tab or the electrode tab bundle is to be formed in a planar area among the side surfaces of the electrode assembly forming the thickness (t, see FIG. 10 ) of the electrode assembly. can
[66]
11 is a perspective view illustrating structures of a first electrode and a fourth electrode constituting a first basic unit according to a third embodiment of the present invention, and FIG. 12 is a second basic unit according to a third embodiment of the present invention. It is a perspective view showing the structure of the second electrode and the fifth electrode constituting the . 13 is a perspective view showing the structures of a third electrode and a sixth electrode constituting a third basic unit according to a third embodiment of the present invention, and FIG. 14 is an electrode of a secondary battery according to a third embodiment of the present invention. It is a perspective view showing the assembly.
[67]
According to the third embodiment of the present invention, the electrode tabs 110b, 120b, 210b, 220b, 310b, and 320b formed on the electrodes 110, 120, 210, 220, 310, 320 are the body parts 110a, 120a, 210a, 220a, 310a, and 320a) may be formed in a convexly protruding curved area among the curved areas formed on the circumferential surface. Accordingly, according to the third embodiment of the present invention, in the electrode assembly of the secondary battery, the electrode tab or the electrode tab bundle is a convexly protruding curved surface among the side surfaces of the electrode assembly forming the thickness (t, see FIG. 14 ) of the electrode assembly. may be formed in the region.
[68]
[69]
battery pack
[70]
The battery pack according to the present invention may include a secondary battery. The description of the secondary battery and the electrode assembly constituting the secondary battery will be replaced with the above description.
[71]
[72]
Secondary battery manufacturing method
[73]
The method of manufacturing a secondary battery according to the present invention may include a preparation step of preparing a plurality of electrodes including a plurality of separators, a body portion and an electrode tab protruding from the body portion in one direction, and having a sheet structure. In addition, the method may further include a disposing step of disposing the electrode and the separator to have a structure in which the electrode and the separator are alternately disposed.
[74]
At this time, according to the present invention, in the disposing step, the electrodes may be arranged so that regions having shapes corresponding to each other and flat regions formed on the circumferential surface of the body portion of the electrode having a sheet structure are adjacent to each other. Accordingly, in the disposing step, a curved surface may be formed on at least some of the side surfaces of the electrode assembly that form the thickness of the electrode assembly formed by alternately disposing the electrode and the separator.
[75]
Meanwhile, according to an example of the method for manufacturing a secondary battery according to the present invention, the electrode tabs formed on the electrodes provided in the preparation step may be respectively formed in planar regions formed on the circumferential surface of the body of the electrode.
[76]
Alternatively, according to another example of the method of manufacturing a secondary battery according to the present invention, the electrode tabs formed on the electrodes provided in the preparation step may be respectively formed in curved areas formed on the circumferential surface of the body of the electrode. For example, the electrode tab may be formed in a concavely indented curved area among curved areas formed on the circumferential surface of the body of the electrode. Alternatively, the electrode tab may be formed in a convexly protruding curved area among the curved areas formed on the circumferential surface of the electrode body.
[77]
Meanwhile, according to the present invention, in the preparation step, the first basic unit 100 (refer to FIG. 4 ) including the first electrode 110 (see FIG. 1 ) and the separator, the second electrode 210 (refer to FIG. 2 ) and the separator This may include preparing a second basic unit 200 (refer to FIG. 4 ) including a, and a third basic unit 300 (refer to FIG. 4 ) including a third electrode 310 . Also, according to the present invention, the disposing step may include disposing the third basic unit between the first basic unit and the second basic unit.
[78]
In addition, the method of manufacturing a secondary battery according to the present invention includes a first electrode tab bundle forming step of forming a first electrode tab bundle by bonding electrode tabs of a plurality of first electrodes to a first basic unit, and a second basic unit. A second electrode tab bundle forming step of forming a second electrode tab bundle by bonding electrode tabs of a plurality of second electrodes to a unit body, and bonding one surface of the third electrode tab to the first electrode tab bundle while bonding the other surface a third electrode tab bonding step of bonding to the second electrode tab bundle; may further include. In this case, the area of ​​the electrode tab formed on the third electrode may be larger than the area of ​​the electrode tab formed on the first electrode and the area of ​​the electrode tab formed on the second electrode.
[79]
Also, after the third electrode tab bonding step, an area in which the electrode tab formed on the third electrode is bonded to the first electrode tab bundle (A1, see FIG. 5 ) and an area in which the second electrode tab bundle is bonded (A2, FIG. 5 ). reference) may be spaced apart from each other in a direction crossing the direction in which the electrode tabs formed on the third electrode protrude from the body portion of the third electrode.
[80]
Meanwhile, the first basic unit may further include a fourth electrode having a polarity different from that of the first electrode, and the second basic unit may further include a fifth electrode having a polarity different from that of the second electrode, and the third The basic unit may further include a sixth electrode having a polarity different from that of the third electrode.
[81]
At this time, the method of manufacturing a secondary battery according to the present invention includes a fourth electrode tab bundle forming step of bonding electrode tabs of a plurality of fourth electrodes to a first basic unit to form a fourth electrode tab bundle, the second basic unit A fifth electrode tab bundle forming step of forming a fifth electrode tab bundle by bonding electrode tabs of a plurality of fifth electrodes to a unit body, and bonding one surface of the sixth electrode electrode tab to the fourth electrode tab bundle while bonding the other surface The method may further include a sixth electrode tab bonding step of bonding the to the fifth electrode tab bundle. In this case, the area of ​​the electrode tab formed on the sixth electrode may be larger than the area of ​​the electrode tab formed on the fourth electrode and the area of ​​the electrode tab formed on the fifth electrode.
[82]
Also, after the sixth electrode tab bonding step, an area in which the electrode tab formed on the sixth electrode is bonded to the fourth electrode tab bundle (A4, see FIG. 6 ) and an area in which the fifth electrode tab bundle is bonded (A5, FIG. 6 ). reference) may be spaced apart from each other in a direction crossing the direction in which the electrode tabs formed on the sixth electrode protrude from the body portion of the sixth electrode.
[83]
[84]
Although the present invention has been described with reference to limited examples and drawings, the present invention is not limited thereto, and it is described below with the technical idea of ​​the present invention by those of ordinary skill in the art to which the present invention pertains. It goes without saying that various implementations are possible within the scope of equivalents of the claims.
[85]
[Explanation of code]
[86]
10: electrode assembly
[87]
100: first basic unit
[88]
110: first electrode
[89]
110a: first body part
[90]
110b: first electrode tab
[91]
120: fourth electrode
[92]
120a: fourth body part
[93]
120b: fourth electrode tab
[94]
200: second basic unit
[95]
210: second electrode
[96]
210a: second body part
[97]
210b: second electrode tab
[98]
220: fifth electrode
[99]
220a: fifth body part
[100]
220b: fifth electrode tab
[101]
300: third basic unit
[102]
310: third electrode
[103]
310a: third body part
[104]
310b: third electrode tab
[105]
320: sixth electrode
[106]
320a: sixth body part
[107]
320b: sixth electrode tab
[108]
P1: first electrode tab bundle
[109]
P2: second electrode tab bundle
[110]
P4: 4th electrode tab bundle
[111]
P5: 5th electrode tab bundle
[112]
A1, A2, A4, A5: junction area
[113]
t: thickness of the electrode assembly
Claims
[Claim 1]
an electrode assembly having a structure in which a plurality of electrodes and a plurality of separators are alternately disposed; including, wherein the electrode includes: a body portion forming a body of the electrode; and an electrode tab protruding from the body in one direction. Including, wherein the electrode has a sheet structure, the upper and lower surfaces of the body portion of the electrode are respectively formed as flat surfaces, and a planar area and a curved area are formed together on the circumferential surface of the body of the plurality of electrodes, respectively, and the The plurality of electrodes are stacked so that the planar region and the curved region formed on the circumferential surface of the body of the plurality of electrodes are adjacent to regions having shapes corresponding to each other, thereby forming a thickness t of the electrode assembly. A secondary battery in which a curved surface is formed on some of the side surfaces of the electrode assembly.
[Claim 2]
The method according to claim 1, The electrode assembly, A first basic unit including a first electrode and a separator; a second basic unit including a second electrode and a separator; and a third electrode, and a third basic unit provided between the first basic unit and the second basic unit, wherein the first basic unit includes a plurality of the electrodes formed on the plurality of first electrodes. Tabs are bonded to each other to form a first electrode tab bundle, and to the second basic unit, a plurality of electrode tabs formed on a plurality of second electrodes are bonded to each other to form a second electrode tab bundle; An area of ​​an electrode tab formed on the electrode is larger than an area of ​​an electrode tab formed on the first electrode and an area of ​​an electrode tab formed on the second electrode, and one surface of the electrode tab formed on the third electrode is the first electrode tab bundle. A secondary battery in which the other surface is bonded to the bundle of the second electrode tabs while being bonded to the battery.
[Claim 3]
The electrode tab of claim 2 , wherein an area (A1) in which the electrode tab formed on the third electrode is bonded to the first electrode tab bundle and an area (A2) in which the second electrode tab bundle is bonded are formed on the third electrode. A secondary battery spaced apart from each other in a direction intersecting the direction in which the third electrode protrudes from the body portion.
[Claim 4]
The secondary battery of claim 1 , wherein each of the electrode tabs formed on the electrode is formed in the planar region formed on a circumferential surface of the body of the electrode.
[Claim 5]
The secondary battery of claim 1 , wherein the electrode tabs formed on the electrodes are respectively formed in the curved area formed on the circumferential surface of the body part of the electrode.
[Claim 6]
The method according to claim 2, wherein the first basic unit further comprises a fourth electrode having a polarity different from that of the first electrode, and the second basic unit further comprises a fifth electrode having a polarity different from that of the second electrode. and the third basic unit further includes a sixth electrode having a polarity different from that of the third electrode, and the plurality of electrode tabs formed on the plurality of fourth electrodes are bonded to each other to the first basic unit. A fourth electrode tab bundle is formed, and the plurality of electrode tabs formed on the plurality of fifth electrodes are bonded to each other on the second basic unit to form a fifth electrode tab bundle, and the electrode tabs formed on the sixth electrode An area of ​​is larger than an area of ​​an electrode tab formed on the fourth electrode and an area of ​​an electrode tab formed on the fifth electrode, and one surface of the electrode tab formed on the sixth electrode is bonded to the fourth electrode tab bundle while the other surface is An area A4 bonded to the fifth electrode tab bundle and an electrode tab formed on the sixth electrode bonded to the fourth electrode tab bundle and an area A5 bonded to the fifth electrode tab bundle include the first A secondary battery in which electrode tabs formed on the sixth electrode are spaced apart from each other in a direction intersecting a direction in which they protrude from the body of the sixth electrode.
[Claim 7]
A preparation step of preparing a plurality of electrodes including a plurality of separators, a body portion and an electrode tab protruding in one direction from the body portion, and having a sheet structure; and disposing the electrode and the separator to have a structure in which the electrode and the separator are alternately disposed. and, in the disposing step, by arranging the electrode such that regions having a shape corresponding to each other and a planar region formed on a circumferential surface of the body portion of the electrode having a sheet structure are disposed adjacent to each other, the electrode and the A method of manufacturing a secondary battery in which a curved surface is formed on a portion of the side surface of the electrode assembly, which forms the thickness (t) of the electrode assembly formed by alternately disposing separators.
[Claim 8]
The method according to claim 7 , wherein the electrode tabs formed on the electrodes provided in the preparation step are respectively formed in the planar region formed on the circumferential surface of the body of the electrode.
[Claim 9]
The method of claim 7 , wherein the electrode tabs formed on the electrode provided in the preparation step are respectively formed in the curved area formed on the circumferential surface of the body of the electrode.
[Claim 10]
The method of claim 7 , wherein the preparing comprises preparing a first basic unit including a first electrode and a separator, a second basic unit including a second electrode and a separator, and a third basic unit including a third electrode ; wherein the disposing step comprises: disposing the third basic unit between the first basic unit and the second basic unit; A method of manufacturing a secondary battery comprising a.
[Claim 11]
The method of claim 10 , further comprising: forming a first electrode tab bundle by bonding a plurality of electrode tabs of the first electrodes to the first basic unit to form a first electrode tab bundle; forming a second electrode tab bundle by bonding a plurality of electrode tabs of the second electrodes to the second basic unit to form a second electrode tab bundle; and a third electrode tab bonding step of bonding one surface of the electrode tab of the third electrode to the first electrode tab bundle and bonding the other surface to the second electrode tab bundle; and an area of ​​the electrode tab formed on the third electrode is larger than an area of ​​the electrode tab formed on the first electrode and an area of ​​the electrode tab formed on the second electrode.
[Claim 12]
12. The method of claim 11, wherein, after the step of bonding the third electrode tab, an area (A1) in which the electrode tab formed on the third electrode is bonded to the first electrode tab bundle and an area (A2) in which the second electrode tab bundle is bonded Silver, a method of manufacturing a secondary battery in which the electrode tabs formed on the third electrode are spaced apart from each other in a direction intersecting a direction in which they protrude from the body of the third electrode.
[Claim 13]
11 . The method of claim 10 , wherein the first basic unit further comprises a fourth electrode having a polarity different from that of the first electrode, and the second basic unit further comprises a fifth electrode having a polarity different from that of the second electrode. , wherein the third basic unit further includes a sixth electrode having a polarity different from that of the third electrode, and bonding electrode tabs of a plurality of the fourth electrodes to the first basic unit to form a fourth electrode tab bundle forming a fourth electrode tab bundle forming step; a fifth electrode tab bundle forming step of forming a fifth electrode tab bundle by bonding the plurality of fifth electrode electrode tabs to the second basic unit; and a sixth electrode tab bonding step of bonding one surface of the electrode tab of the sixth electrode to the fourth electrode tab bundle and bonding the other surface to the fifth electrode tab bundle; A method of manufacturing a secondary battery further comprising a.
[Claim 14]
A battery pack comprising the secondary battery according to claim 1.