Title of Invention: Cylindrical Battery and Cylindrical Battery Manufacturing Method
technical field
[One]
Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0004258 dated January 13, 2020, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[3]
The present invention relates to a cylindrical cell and a method for manufacturing a cylindrical cell.
background
[4]
Recently, an increase in the price of an energy source due to the depletion of fossil fuels, an interest in environmental pollution is amplified, and the demand for an eco-friendly alternative energy source is becoming an indispensable factor for future life. Accordingly, research on various power generation technologies such as nuclear power, solar power, wind power, and tidal power continues, and interest in power storage devices for using the generated energy more efficiently.
[5]
Moreover, as the technology development and demand for mobile devices and battery vehicles increase, the demand for batteries as an energy source is rapidly increasing, and accordingly, a lot of research on batteries capable of meeting various needs is being conducted. In particular, in terms of materials, there is a high demand for lithium secondary batteries such as lithium ion batteries and lithium ion polymer batteries having advantages such as high energy density, discharge voltage, and output stability.
[6]
Secondary batteries are classified according to the structure of an electrode assembly in which a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode are stacked. Representatively, a jelly-roll type (wound type) electrode assembly in which a long sheet-type positive electrode and negative electrode are wound with a separator interposed therebetween, a plurality of positive and negative electrodes cut in units of a predetermined size with a separator interposed therein and stack-type (stacked) electrode assemblies stacked sequentially. Recently, in order to solve the problems of the jelly-roll-type electrode assembly and the stack-type electrode assembly, the jelly-roll type and the stacked type are mixed. As an electrode assembly having a structure, a stack/folding electrode assembly having a structure in which unit cells in which anode and cathode of a predetermined unit are stacked with a separator interposed therebetween are sequentially wound on a separator film has been developed.
[7]
According to the purpose of use, these electrode assemblies are accommodated in a pouch case, a cylindrical can, and a prismatic case to manufacture a battery.
[8]
Among them, the cylindrical battery has advantages of being easy to manufacture and having a high energy density per weight, and thus is used as an energy source for various devices ranging from portable computers to battery vehicles.
[9]
1 is a schematic diagram showing a conventional cylindrical battery.
[10]
Referring to FIG. 1 , the cylindrical battery 100 accommodates the jelly-roll type electrode assembly 120 in the cylindrical case 130 , and after injecting the electrolyte into the cylindrical case 130 , it is placed at the open top of the cylindrical case 130 . It is manufactured by combining the top cap 140 .
[11]
The jelly-roll type electrode assembly 120 has a structure in which a positive electrode 121, a separator 122, and a negative electrode 123 are sequentially stacked and wound in a round shape, and the center of the electrode assembly 120, which is its winding core, has a cylindrical center. A pin 150 is inserted. The center pin 150 functions as a passage for fixing and supporting the electrode assembly 120 and for discharging gas generated by an internal reaction during charging, discharging, and operation. However, the center pin 150 may not be used depending on the specifications of the cylindrical battery 100 .
[12]
During the charging/discharging process of the cylindrical battery 100 , the electrode of the electrode assembly 120 repeats expansion and contraction. Accordingly, structural deformation in which the electrode assembly 120 is twisted occurs. In particular, the deformation is more severe in the center of the electrode assembly 120 where stress is concentrated.
[13]
In addition, in the cylindrical battery 100 , high thermal energy is generated inside the cylindrical battery 100 during the charging and discharging process. However, the conventional cylindrical battery 100 does not have a system capable of rapidly discharging the thermal energy. In particular, in recent years, the demand for a cylindrical battery capable of high capacity and high output is increasing. Accordingly, when an electrode loaded with a high active material is used, there is a problem that runaway may occur.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[14]
An object of the present invention is to provide a cylindrical battery and a cylindrical battery manufacturing method capable of preventing deformation and runaway of an electrode assembly.
[15]
However, the problems to be solved by the embodiments of the present invention are not limited to the above-described problems and may be variously expanded within the scope of the technical idea included in the present invention.
means of solving the problem
[16]
A cylindrical battery according to an embodiment of the present invention includes electrode assemblies and top cap assemblies positioned above the electrode assemblies, and the top cap assemblies may be electrically separated from each other by an insulating member.
[17]
The top cap assembly includes a first top cap assembly and a second top cap assembly, wherein the first top cap assembly includes a first top cap, a first current blocking member and a first gas reservoir, and the second top The cap assembly may include a second top cap, a second current blocking member, and a second gas storage unit.
[18]
The insulating member may include an upper insulating member and a lower insulating member.
[19]
The upper insulating member may have a “Π” cross-sectional shape.
[20]
The upper insulating member may be coupled to a structure surrounding a middle portion of the lower insulating member.
[21]
The lower insulating member may be positioned between the first current blocking member and the second current blocking member and may electrically insulate the first current blocking member and the second current blocking member.
[22]
The upper insulating member may be attached to the first current blocking member and the second current blocking member.
[23]
Even if any one of the first current blocking member and the second current blocking member is operated, the upper insulating member may move upward and protrude to the outside.
[24]
When the first current blocking member or the second current blocking member operates, the gas generated from the electrode assembly may be collected in the first gas storage unit and the second gas storage unit.
[25]
When the upper insulating member moves upward to a first height L1 or higher by the pressure of the gas collected in the first gas storage unit and the second gas storage unit, the first gas storage unit and the second gas storage unit The gas collected in the unit may be discharged to the outside.
[26]
The insulating member may include a first insulating member, a second insulating member, and a lower insulating member.
[27]
The first insulating member and the second insulating member may be separated from each other.
[28]
The first insulating member may be attached to the first current blocking member, and when the first current blocking member operates, the first insulating member may move upward and protrude.
[29]
The second insulating member may be attached to the second current blocking member, and when the second current blocking member operates, the second insulating member may move upward and protrude.
[30]
The electrode assembly may include a first electrode assembly and a second electrode assembly, and the first electrode assembly may be located in a central portion of the second electrode assembly.
[31]
A first positive electrode tab of the first electrode assembly may be electrically connected to the first top cap assembly, and a second positive electrode tab of the second electrode assembly may be electrically connected to the second top cap assembly.
[32]
A method of manufacturing a cylindrical battery according to an embodiment of the present invention includes manufacturing a first electrode assembly by winding a first positive electrode, a first separator, and a first negative electrode; manufacturing a second electrode assembly by winding a second positive electrode, a second separator, and a second negative electrode; inserting the first electrode assembly into a central portion of the second electrode assembly; electrically connecting a first positive electrode tab of the first electrode assembly to a first top cap assembly; and electrically connecting a second positive electrode tab of the second electrode assembly to a second top cap assembly.
[33]
A method for manufacturing a cylindrical battery according to another embodiment of the present invention includes manufacturing a first electrode assembly by winding a first positive electrode, a first separator, and a first negative electrode; manufacturing a second electrode assembly by winding a second positive electrode, a second separator, and a second negative electrode stack using the first electrode assembly as a core; inserting the first electrode assembly into a central portion of the second electrode assembly; electrically connecting a first positive electrode tab of the first electrode assembly to a first top cap assembly; and electrically connecting a second positive electrode tab of the second electrode assembly to a second top cap assembly.
Effects of the Invention
[34]
As described above, in the cylindrical battery according to the embodiment of the present invention, damage and deformation of the cylindrical battery can be prevented by using electrically separated top cap assemblies.
Brief description of the drawing
[35]
1 is a schematic diagram showing a conventional cylindrical battery.
[36]
2 is a schematic diagram of a cylindrical battery according to an embodiment of the present invention.
[37]
3 is a schematic cross-sectional view of the top cap assembly of 2 cut along A-A'.
[38]
4 is a schematic view showing that the upper insulating member of FIG. 3 is drawn upward.
[39]
FIG. 5 is a schematic view showing the insulating member of FIG. 2 .
[40]
6 is a schematic cross-sectional view showing a top cap assembly according to another embodiment of the present invention.
[41]
7 is a schematic cross-sectional view showing a top cap assembly according to another embodiment of the present invention.
[42]
FIG. 8 is a schematic diagram illustrating manufacturing the electrode assembly of FIG. 2 according to an embodiment of the present invention.
[43]
FIG. 9 is a schematic diagram illustrating the manufacturing of the electrode assembly of FIG. 2 according to another embodiment of the present invention.
Modes for carrying out the invention
[44]
Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.
[45]
Also, people In the entire set, when a part "includes" a certain element, it means that other elements may be further included, rather than excluding other elements, unless otherwise stated.
[46]
Also, throughout the specification, “upward” means the opposite direction in which gravity acts.
[47]
2 is a schematic diagram of a cylindrical battery according to an embodiment of the present invention. 3 is a schematic cross-sectional view of the top cap assembly of 2 cut along A-A'. 4 is a schematic view showing that the upper insulating member of FIG. 3 is drawn upward. FIG. 5 is a schematic view showing the insulating member of FIG. 2 .
[48]
2 to 5 , the cylindrical battery 200 may have a structure in which a jelly-roll type electrode assembly 220 is inserted into a battery case (not shown). A positive electrode tab 230 may be formed on an upper portion of the electrode assembly 220 to be electrically connected to the top cap assembly 210 . A negative electrode tab 240 may be formed at a lower portion of the electrode assembly 220 to be electrically connected to the battery case. The positive electrode tab 230 may include a first positive electrode tab 231 and a second positive electrode tab 232 . The negative electrode tab 240 may include a first negative electrode tab 241 and a second negative electrode tab 242 .
[49]
The top cap assembly 210 may include a first top cap assembly 211 and a second top cap assembly 212 . The first top cap assembly 211 and the second top cap assembly 212 may be electrically separated by the insulating member 250 . The first top cap assembly 211 and the second top cap assembly 212 may have a structure that is symmetrical with respect to the insulating member 250 .
[50]
The first positive electrode tab 231 may be electrically connected to the second top cap assembly 212 . The second positive electrode tab 232 may be electrically connected to the first top cap assembly 211 .
[51]
The insulating member 250 may pass through the center of the top cap assembly 210 and may be formed to extend in the length and width directions of the top cap assembly 210 . The insulating member 250 may include an upper insulating member 250 - 1 and a lower insulating member 250 - 2 .
[52]
The first top cap assembly 211 includes a first upper cap 211-1, a first current blocking member (CURRENT INTERRUPTIVE DEVICE: 211-2), a first gas storage unit 211-3, and a gasket 211-4. ) may be included. The first upper cap 211-1 may form a positive electrode terminal in a form exposed to the outside. The first current blocking member 211 - 2 may be formed under the upper insulating member 250 - 1 .
[53]
The second top cap assembly 212 includes a second upper cap 212-1, a second current blocking member 212-2, a second gas storage unit 212-3, and a second gasket 212-4. may include The second upper cap 212-1 may form a positive electrode terminal in a form exposed to the outside of the cylindrical battery 200 . The second current blocking member 212 - 2 may be formed under the upper insulating member 250 - 1 .
[54]
The upper insulating member 250 - 1 may have a structure attached to the first current blocking member 211 - 2 and the second current blocking member 212 - 2 . Accordingly, even when either one of the first current blocking member 211-2 and the second current blocking member 212-2 operates, the upper insulating member 250-1 moves upward and may protrude to the outside.
[55]
For example, when the first current blocking member 211-2 operates, the upper insulating member 250-1 moves upward and the second current blocking member 212-2 attached to the upper insulating member 250-1 is operated. ) can also move upwards. In addition, when the second current blocking member 212-2 operates, the upper insulating member 250-1 moves upward, and the first current blocking member 211-2 attached to the upper insulating member 250-1 also moves upward. You can move upwards together.
[56]
When the upper insulating member 250 - 1 moves upward and protrudes to the outside, the operator can visually check the degree of protrusion of the upper insulating member 250 - 1 . In addition, the degree of generation of the internal gas may be determined through the degree of protrusion of the upper insulating member 250 - 1 .
[57]
The upper insulating member 250-1 may have a “Π” shape in cross section cut along A-A'. The upper insulating member 250 - 1 may be formed at an intermediate portion in the longitudinal direction Y of the lower insulating member 250 - 2 . The upper insulating member 250-1 may be coupled to a structure surrounding the middle portion of the lower insulating member 250-2.
[58]
The lower insulating member 250 - 2 may be positioned between the first current blocking member 211 - 2 and the second current blocking member 212 - 2 . The first current blocking member 211 - 2 and the second current blocking member 212 - 2 may be electrically insulated from each other by the lower insulating member 250 - 2 .
[59]
When the first current blocking member 211-2 or the second current blocking member 212-2 operates, the gas generated from the electrode assembly 220 is transferred to the first gas storage unit 211-3 and the second gas storage unit (211-3). 212-3). Then, the upper insulating member 250-1 moves upward to a first height L1 or higher by the pressure of the gas collected in the first gas storage unit 211-3 and the second gas storage unit 212-3. When the gas is collected in the first gas storage unit 211-3 and the second gas storage unit 212-3, the gas may be discharged to the outside.
[60]
The first gas storage unit 211-3 may include a first indentation portion 211-3-1 and a second indentation portion 211-3-2. The first indentation portion 211-3-1 may be a space formed by being indented toward the first upper cap 211-1. The second indentation portion 211-3-2 may be a space formed by being indented toward the upper insulating member 250-1. The first gas storage unit 211-3 may be formed between the first indentation portion 211-3-1, the second indentation portion 211-3-2, and the first current blocking member 211-2. have.
[61]
When the upper insulating member 250-1 moves upward above the first height L1, the air collected in the first gas storage unit 211-3 is exposed while the second indentation part 211-3-2 is exposed to the outside. may be discharged to the outside.
[62]
The size of the path through which the gas collected in the first gas storage unit 211-3 is discharged may be determined according to the height L3 and the width L2 of the second indentation portion 211-3-2. In particular, the larger the width L2, the larger the gas discharge path may be formed.
[63]
The first contact portion 211-5 may be a contact portion between the first upper cap 211-1 and the first current blocking member 211-2. When the first current blocking member 211 - 2 moves upward, the first contact portion 211 - 5 is opened and the internal gas may be collected in the first gas storage unit 211-3 . Here, the opening of the first contact part 211-5 means that the first upper cap 211-1 and the first current blocking member 211-2 are separated. The internal gas may move through a space generated when the first upper cap 211-1 and the first current blocking member 211-2 are separated and may be collected in the first gas storage unit 211-3.
[64]
The second top cap assembly 212 may have the same structure as the first top cap assembly 211 . Accordingly, a detailed description of the second top tab assembly 212 will be omitted.
[65]
The second gas storage unit 212 - 3 may have the same structure as the first gas storage unit 211-3 . Also, the second gas storage unit 212 - 3 may collect and discharge gas in the same manner as the first gas storage unit 211-3 . Accordingly, a description of the second gas storage unit 212 - 3 will be omitted.
[66]
The first gas storage unit 211-3 and the second gas storage unit 212-3 may include extinguishing gas. The extinguishing gas may be carbon dioxide or nitrogen gas. The extinguishing gas may prevent a fire due to runaway that may occur due to an abnormal operation of the cylindrical battery 200 .
[67]
6 is a schematic cross-sectional view showing a top cap assembly according to another embodiment of the present invention.
[68]
Referring to FIG. 6 , the top cap assembly 310 may include a first top cap assembly 311 and a second top cap assembly 312 . The first top cap assembly 311 and the second top cap assembly 312 may be electrically separated from each other by the insulating member 350 . The first top cap assembly 311 and the second top cap assembly 312 may have a mutually symmetrical structure with respect to the insulating member 350 .
[69]
The insulating member 350 may pass through the center of the top cap assembly 310 and may be formed to extend in the length and width directions of the top cap assembly 310 . The insulating member 350 may include a first insulating member 350 - 1 , a second insulating member 350 - 2 , and a lower insulating member 350 - 3 .
[70]
The first top cap assembly 311 may include a first upper cap 311-1, a first current blocking member 311-2, a first gas storage unit 311-3, and a gasket 311-4. can The first upper cap 311-1 may form a positive electrode terminal in a form exposed to the outside. The first current blocking member 311 - 2 may be formed under the first insulating member 350 - 1 .
[71]
The second top cap assembly 312 may include a second upper cap 312 - 1 , a second current blocking member 312 - 2 , a gas storage unit 312 - 3 , and a second gasket 312 - 4 . can The second upper cap 312-1 may form a positive electrode terminal in a form exposed to the outside. The second current blocking member 312 - 2 may be formed under the second insulating member 350 - 2 .
[72]
The first insulating member 350 - 1 may have a structure attached to the first current blocking member 311 - 2 . Accordingly, when the first current blocking member 311 - 2 operates, the first insulating member 350 - 1 may move upward and protrude.
[73]
The second insulating member 350 - 2 may have a structure attached to the second current blocking member 312 - 2 . Accordingly, when the second current blocking member 312 - 2 operates, the second insulating member 350 - 2 may move upward and protrude.
[74]
The first insulating member 350-1 and the second insulating member 3 50-2) may be a structure separated from each other. Accordingly, the first insulating member 350-1 and the second insulating member 350-2 may operate separately.
[75]
The first current blocking member 311 - 2 and the second current blocking member 312 - 2 may be electrically separated by the lower insulating member 350 - 3 . In addition, the first current blocking member 311 - 2 and the second current blocking member 312 - 2 do not affect the mutual operation.
[76]
When the first current blocking member 311 - 2 operates, the internal gas may be collected in the first gas storage unit 311-3 . And, when the first insulating member 350-1 moves upward to a height S1 or higher by the gas pressure collected in the first gas storage unit 311-3, the gas collected in the first gas storage unit 311-3 is Gas may be vented to the outside.
[77]
The first gas storage unit 311-3 may include a first indentation portion 311-3-1 and a second indentation portion 311-3-2. The first indentation portion 311-3-1 may be a space formed by being indented toward the first upper cap 311-1. The second indentation portion 311-3-2 may be a space formed by being depressed toward the first insulating member 350-1. The first gas storage unit 311-3 may be formed between the first indentation portion 311-3-1, the second indentation portion 311-3-2, and the first current blocking member 311-2. have.
[78]
When the first insulating member 350-1 moves upward above the height S1, the second indentation part 311-3-2 is exposed to the outside, and the air collected in the first gas storage part 311-3 is released. can be discharged outside.
[79]
The size of the path through which the gas collected in the first gas storage unit 311-3 is discharged may be determined according to the height S3 and the width S2 of the second indentation part 311-3-2. In particular, the larger the width L2, the larger the gas discharge path may be formed.
[80]
The first contact portion 311 - 5 may be a contact portion between the first upper cap 311-1 and the first current blocking member 311 - 2 . When the first current blocking member 311 - 2 moves upward, the first contact portion 311 - 5 is opened, and the distribution gas may be collected in the first gas storage unit 311-3 . Here, the opening of the first contact part 511-5 means that the first upper cap 311-1 and the first current blocking member 311-2 are separated. The internal gas may move through a space generated when the first upper cap 311-1 and the first current blocking member 311-2 are separated and may be collected in the first gas storage unit 311-3.
[81]
The second top cap assembly 312 may have the same structure as the first top cap assembly 311 . Accordingly, a description of the second top tab assembly 312 will be omitted.
[82]
The second gas storage unit 312 - 3 may have the same structure as the first gas storage unit 311-3 . Also, the second gas storage unit 312 - 3 may collect and discharge gas in the same manner as the first gas storage unit 311-3 . Accordingly, a description of the second gas storage unit 312 - 3 will be omitted.
[83]
The first gas storage unit 311-3 and the second gas storage unit 312-3 may include extinguishing gas. The extinguishing gas may be carbon dioxide or nitrogen gas. The extinguishing gas may prevent a fire due to runaway that may occur due to an abnormal operation of the cylindrical battery.
[84]
When the first insulating member 350-1 and the second insulating member 350-2 move upward and protrude to the outside, the operator operates the first insulating member 350-1 and the second insulating member 350-2. The degree of protrusion can be visually confirmed. Further, the degree of generation of the internal gas may be determined through the degree of protrusion of the first insulating member 350 - 1 and the second insulating member 350 - 2 .
[85]
7 is a schematic cross-sectional view showing a top cap assembly according to another embodiment of the present invention.
[86]
Referring to FIG. 7 , the top cap assembly 410 may include a first top cap assembly 411 and a second top cap assembly 412 . The first top cap assembly 411 and the second top cap assembly 412 may be electrically separated from each other by the insulating member 450 .
[87]
The insulating member 450 may pass through the center of the top cap assembly 410 and may be formed to extend in the length and width directions of the top cap assembly 410 . The insulating member 450 may include an upper insulating member 450-1 and a lower insulating member 450-2.
[88]
The first top cap assembly 411 may include a first top cap 411-1, a first current blocking member 411-2, a first gas storage unit 411-3, and a gasket 411-4. can The first upper cap 411-1 may form a positive electrode terminal in a form exposed to the outside. The first current blocking member 411 - 2 may be formed under the upper insulating member 450-1.
[89]
The second top cap assembly 412 may include a second upper cap 412-1, a second current blocking member 412-2, a gas storage unit 412-3, and a second gasket 412-4. can The second upper cap 412-1 may form a positive electrode terminal in a form exposed to the outside. The second current blocking member 412 - 2 may be formed under the upper insulating member 450-1.
[90]
The upper insulating member 450-1 may have a structure attached to the first current blocking member 411-2 and the second current blocking member 412-2. Accordingly, even when either one of the first current blocking member 411 - 2 and the second current blocking member 412 - 2 operates, the upper insulating member 450-1 may move upward and protrude. For example, when the first current blocking member 411-2 operates, the upper insulating member 450-1 moves upward and the second current blocking member 412-2 attached to the upper insulating member 450-1 is operated. ) can also move upwards. In addition, when the second current blocking member 412-2 operates, the upper insulating member 450-1 moves upward, and the first current blocking member 411-2 attached to the upper insulating member 450-1 also moves upward. You can move upwards together.
[91]
When the upper insulating member 450-1 moves upward and protrudes to the outside, the operator can visually check the degree of protrusion of the upper insulating member 450-1. In addition, the degree of generation of the internal gas may be determined through the degree of protrusion of the upper insulating member 450-1.
[92]
When the first current blocking member 411 - 2 or the second current blocking member 412 - 2 operates, the internal gas is collected in the first gas storage unit 411-3 and the second gas storage unit 412 - 3 . can be However, according to the present embodiment, unlike the above-described embodiments, the upper insulating member 450-1 is caused by the gas pressure collected in the first gas storage unit 411-3 and the second gas storage unit 412-3. ) moves upward above the second height M1 , the gas collected in the first gas storage unit 411-3 and the second gas storage unit 412-3 is not discharged to the outside. However, when the current blocking members 411-2 and 412-2 exceed the second height M1 due to excessive gas generation due to external heating, etc., the upper insulating member 450-1 and the current blocking member ( 411-2 and 412-2) may be discharged to the outside together, and the internal gas may be discharged to the outside.
[93]
The first gas storage unit 411-3 may be a space formed by being recessed toward the first upper cap 411-1. The first gas storage unit 411-3 may be formed between the first upper cap 411-1, the upper insulating member 450-1, and the first current blocking member 411-2.
[94]
The first contact portion 411 - 5 may be a contact portion between the first upper cap 411-1 and the first current blocking member 411 - 2 . When the first current blocking member 411 - 2 moves upward, the first contact part 411 - 5 is opened, and the internal gas may be collected in the first gas storage part 411-3 . Here, the opening of the first contact part 411-5 means that the first upper cap 411-1 and the first current blocking member 411-2 are separated. The internal gas may move through a space generated when the first upper cap 411-1 and the first current blocking member 411-2 are separated and may be collected in the first gas storage unit 411-3.
[95]
The second top cap assembly 412 may have the same structure as the first top cap assembly 411 . Accordingly, a description of the structure of the second top tab assembly 412 will be omitted.
[96]
The second gas storage unit 412 - 3 may have the same structure as the first gas storage unit 411-3 . Also, the second gas storage unit 412 - 3 may collect and discharge gas in the same manner as the first gas storage unit 411-3 . Accordingly, a description of the second gas storage unit 412 - 3 will be omitted.
[97]
The first gas storage unit 411-3 and the second gas storage unit 412-3 may include extinguishing gas. The extinguishing gas may be carbon dioxide or nitrogen gas. The extinguishing gas may prevent a fire due to runaway that may occur due to an abnormal operation of the cylindrical battery.
[98]
FIG. 8 is a schematic diagram illustrating manufacturing the electrode assembly of FIG. 2 according to an embodiment of the present invention. FIG. 9 is a schematic diagram illustrating the manufacturing of the electrode assembly of FIG. 2 according to another embodiment of the present invention.
[99]
2, 8 and 9 , the electrode assembly 220 may include a first electrode assembly 221 and a second electrode assembly 222 . The first electrode assembly 221 may be located in the center of the second electrode assembly 222 .
[100]
The first electrode assembly 221 may have a structure in which the first positive electrode 221-1, the first separator 221-2, and the first negative electrode 221-3 are sequentially wound. A first positive electrode tab 231 may be formed on an upper portion of the first electrode assembly 221 to be electrically connected to the first top cap assembly 211 . A first negative electrode tab 241 may be formed under the first electrode assembly 221 to be electrically connected to the battery case.
[101]
The second electrode assembly 222 may have a structure in which the second positive electrode 222-1, the second separator 222-2, and the second negative electrode 222-3 are sequentially wound. On the upper portion of the second electrode assembly 222, a second positive electrode tab (232 may be formed to be electrically connected to the second top cap assembly 212 . A second negative electrode tab 242 may be formed under the second electrode assembly 222 to be electrically connected to the battery case.
[102]
In the first electrode assembly 221 , the first negative electrode 221-3 may include an anode active material. In the second electrode assembly 222 , the second negative electrode 222 - 3 may include an anode active material. The silicon (Si) content of the first cathode 221-3 may be 25% to 75% compared to the silicon content of the second cathode 222-3. The loading amount of the negative active material of the first negative electrode 221-3 may be 40% to 70% compared to the loading amount of the negative electrode active material of the second negative electrode 222-3.
[103]
With this structure, the structure of the electrode assembly 220 is prevented from being deformed due to volume expansion and heat generation of the first negative electrode 221-3 and the second negative electrode 222-3 during the charging and discharging process of the cylindrical battery 200 . can be prevented
[104]
The electrode assembly 220 may be manufactured by various methods. As an example, the first electrode assembly 221 and the second electrode assembly 222 may be wound and manufactured, respectively, and the first electrode assembly 221 may be manufactured by inserting the first electrode assembly 221 into the central portion 260 of the second electrode assembly 222 . have. The first electrode assembly 221 may be manufactured by winding a stack of the first positive electrode 221-1, the first separator 221-2, and the first negative electrode 221-3. The second electrode assembly 222 may be manufactured by winding a stack of the second positive electrode 222-1, the second separator 222-2, and the second negative electrode 222-3. In this case, the second electrode assembly 222 may wind the second electrode assembly 222 by using a core (not shown) equal to the diameter d2 of the central portion 260 . Also, the diameter d2 of the central portion 260 may be the same as the diameter d1 of the first electrode assembly 221 .
[105]
The electrode assembly 220 is also prepared by first manufacturing the first electrode assembly 221 , and then using the first electrode assembly 221 as a winding core to form a second positive electrode 222-1 and a second separator 222-2. And the second electrode assembly 222 may be manufactured by winding the stack of the second negative electrode 222 - 3 .
[106]
In the cylindrical battery according to the embodiments of the present invention, since electrically separated electrode assemblies and top cap assemblies are included in a single structure, deformation of the electrode assemblies generated during charging and discharging can be minimized. In particular, it is possible to prevent stress from being concentrated in the central portions of the electrode assemblies.
[107]
In addition, since each electrode assembly is managed by electrically separated top cap assemblies, a system capable of rapidly dissipating thermal energy generated therein may be provided.
[108]
Those of ordinary skill in the art to which the present invention pertains will be able to make various applications and modifications within the scope of the present invention based on the above content.
[109]
Explanation of symbols
[110]
210, 310, 410: top cap assembly
[111]
211-1, 311-1, 411-1: first top cap
[112]
212-1, 312-1, 412-1: second top cap
[113]
211-2, 311-2, 411-2: first current blocking member
[114]
212-2, 312-2, 412-2: second current blocking member
[115]
250, 350, 450: insulation member
Claims
[Claim 1]
A cylindrical battery comprising: electrode assemblies; and top cap assemblies positioned above the electrode assemblies, wherein the top cap assemblies are electrically separated from each other by an insulating member.
[Claim 2]
The first top cap assembly of claim 1 , wherein the top cap assembly includes a first top cap assembly and a second top cap assembly, and the first top cap assembly includes a first top cap, a first current blocking member, and a first gas storage unit. wherein the second top cap assembly includes a second upper cap, a second current blocking member, and a second gas storage unit.
[Claim 3]
The cylindrical battery according to claim 2, wherein the insulating member includes an upper insulating member and a lower insulating member.
[Claim 4]
The cylindrical battery of claim 3 , wherein the upper insulating member has a “Π” cross-sectional shape.
[Claim 5]
The cylindrical battery of claim 4, wherein the upper insulating member is coupled to a structure surrounding a middle portion of the lower insulating member.
[Claim 6]
The cylindrical battery of claim 3 , wherein the lower insulating member is positioned between the first current blocking member and the second current blocking member and electrically insulates the first current blocking member and the second current blocking member.
[Claim 7]
The cylindrical battery according to claim 3, wherein the upper insulating member is attached to the first current blocking member and the second current blocking member.
[Claim 8]
The cylindrical battery of claim 7 , wherein the upper insulating member moves upward and protrudes outward even when any one of the first current blocking member and the second current blocking member operates.
[Claim 9]
The cylindrical battery of claim 7 , wherein when the first current blocking member or the second current blocking member operates, the gas generated from the electrode assembly is collected in the first gas storage unit and the second gas storage unit.
[Claim 10]
The method of claim 9, wherein when the upper insulating member moves upward to a height L1 or higher by the pressure of the gas collected in the first gas storage unit and the second gas storage unit, the first gas storage unit and the A cylindrical battery in which the gas collected in the second gas storage unit is discharged to the outside.
[Claim 11]
The cylindrical battery of claim 3 , wherein the insulating member includes a first insulating member, a second insulating member, and a lower insulating member.
[Claim 12]
The cylindrical battery of claim 11 , wherein the first insulating member and the second insulating member are separated from each other.
[Claim 13]
The cylindrical battery of claim 12 , wherein the first insulating member is attached to the first current blocking member, and when the first current blocking member is operated, the first insulating member moves upward and protrudes.
[Claim 14]
The cylindrical battery of claim 12 , wherein the second insulating member is attached to the second current blocking member, and when the second current blocking member operates, the second insulating member moves upward and protrudes.
[Claim 15]
The cylindrical battery of claim 2 , wherein the electrode assembly includes a first electrode assembly and a second electrode assembly, and the first electrode assembly is located in a central portion of the second electrode assembly.
[Claim 16]
The method of claim 15 , wherein a first positive electrode tab of the first electrode assembly is electrically connected to the first top cap assembly, and a second positive electrode tab of the second electrode assembly is electrically connected to the second top cap assembly. cylindrical battery.
[Claim 17]
manufacturing a first electrode assembly by winding a first positive electrode, a first separator, and a first negative electrode; manufacturing a second electrode assembly by winding a second positive electrode, a second separator, and a second negative electrode; inserting the first electrode assembly into a central portion of the second electrode assembly; electrically connecting a first positive electrode tab of the first electrode assembly to a first top cap assembly; and electrically connecting a second positive tab of the second electrode assembly to a second top cap assembly; Cylindrical battery manufacturing method comprising a.
[Claim 18]
manufacturing a first electrode assembly by winding a first positive electrode, a first separator, and a first negative electrode; manufacturing a second electrode assembly by winding a second positive electrode, a second separator, and a second negative electrode stack using the first electrode assembly as a core; inserting the first electrode assembly into a central portion of the second electrode assembly; electrically connecting a first positive electrode tab of the first electrode assembly to a first top cap assembly; and electrically connecting a second positive tab of the second electrode assembly to a second top cap assembly; Cylindrical battery manufacturing method comprising a.