Cover assembly for secondary battery and secondary battery including the same

Abstract

The present disclosure relates to a cover assembly for a secondary battery, including a cover plate provided with one or more opening portions, and one or more terminal members inserted into the opening portions and exposed from one face of the cover plate, the terminal members including a terminal, a bracket, and an insulating member, and being integrally formed by insert injection molding.

Description

Technical Field

[0001] This disclosure relates to a cover assembly for a secondary battery and a secondary battery including the same. Background Technology

[0002] Unlike primary batteries, rechargeable batteries can be recharged, and their demand is gradually increasing due to their ability to be miniaturized and have large capacities. These rechargeable batteries are manufactured in the form of battery packs consisting of a single cell or dozens of cells connected together, and are widely used as power sources for motors in mobile phones, laptops, and electric vehicles.

[0003] The secondary battery includes a casing with one open side, a cover assembly covering one side of the casing, and an electrode assembly inserted inside the casing. The electrode assembly includes a positive electrode and a negative electrode, and electrical energy is generated through electrochemical reactions between these electrodes. The positive and negative electrodes are electrically connected to the casing or cover assembly, particularly the cover assembly, which is connected to the positive or negative electrode and is assembled with various structures such as exposed terminals and insulators. Various studies are underway to prevent electrical short circuits in this cover assembly while improving productivity and process efficiency. Summary of the Invention

[0004] (a) Technical problems to be solved One embodiment of this disclosure can provide a cover assembly for a secondary battery with improved assemblability and productivity, and a secondary battery including the same.

[0005] Furthermore, one embodiment of this disclosure may provide a cover assembly for a secondary battery with a simple structure and improved electrical characteristics, and a secondary battery including the same.

[0006] On the other hand, this disclosure can be widely applied to the fields of electric vehicles, battery charging stations, energy storage systems (ESS), and other green technologies that utilize batteries, such as solar power (photovoltaics) and wind power. Furthermore, this disclosure can be used for eco-friendly mobility, including electric vehicles and hybrid vehicles, to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0007] (II) Technical Solution One embodiment of this disclosure includes a cover assembly for a secondary battery and a secondary battery including the same.

[0008] In one embodiment, the secondary battery cover assembly may include: a cover plate having one or more openings; and one or more terminal components inserted into the openings and exposed from one side of the cover plate, the terminal components including terminals, supports and insulating components, and integrally formed by insert injection molding.

[0009] In one embodiment, the cross-section of the terminal component may be at least one of circular and elliptical shapes.

[0010] In one embodiment, the terminal may be cylindrical, the support may be a hollow cylinder with an internal channel, and the insulating component may be located between the terminal and the support.

[0011] In one embodiment, one side of the terminal component may be exposed from one side of the cover plate, and one side of the terminal component may be provided with the terminal and the insulating component. The other side of the terminal component may be provided with the terminal, the bracket and the insulating component. The insulating component may include one or more recesses, and the recesses are provided on one side of the terminal component.

[0012] In one embodiment, the insulating member may include a recessed portion along the edge of the insulating member, into which at least a portion of the bracket may be inserted.

[0013] In one embodiment, at least one of the outer surface of the terminal and the inner circumferential surface of the bracket may include a surface roughening portion.

[0014] In one embodiment, at least one of the outer surface of the terminal and the inner circumferential surface of the bracket may include threads.

[0015] In one embodiment, the terminal may be cylindrical with a first height, and the bracket may be a hollow cylinder with a second height less than the first height and an internal channel. The insulating component may include: an inner support portion disposed between the outer surface of the terminal and the inner surface of the bracket; an outer support portion covering at least a portion of the outer surface of the bracket; and an extension portion connecting one end of the inner support portion and the outer support portion. At least a portion of the bracket may be inserted into the space formed by the inner support portion, the outer support portion, and the extension portion.

[0016] In one embodiment, the inner support portion may have a third height, the outer support portion may have a fourth height less than the third height, the fourth height of the outer support portion may be less than the second height of the bracket, the inner surface of the bracket may be configured to be in integral contact with the inner support portion of the insulating component, the outer surface of the bracket may be in contact with the outer support portion of the insulating component, and may include at least a portion of the exposed surface.

[0017] In one embodiment, the exposed surface of the bracket may be welded to the cover plate, and the other end of the external support portion of the insulating component may be mounted on one side of the cover plate.

[0018] In one embodiment, the longitudinal sections of the inner support, the outer support, and the extension may be in the shape of a "∩", and the other end of the outer support may further include a friction surface.

[0019] In one embodiment, the device may further include: an exhaust component disposed on the cover plate; one or more current collectors connected to the terminal component on the other side of the cover plate; and an insulating sheet between the current collector and the cover plate. The cover plate may further include an exhaust port, the exhaust component being disposed on the exhaust port, one side of the terminal component being exposed from one side of the cover plate, and the other side of the terminal component being connected to the current collector.

[0020] In one embodiment, at least a portion of the terminal and the bracket may further include a functional layer.

[0021] In one embodiment, the functional layer may be formed by surface treating at least one of the terminal and the support prior to the insert injection molding, and the functional layer may contain at least one of one or more functional groups and one or more nanopores.

[0022] In one embodiment, the functional group may include at least one of hydroxyl (-OH), amino (-NH2), and epoxy (-COC-).

[0023] In one embodiment, the secondary battery may include: an electrode assembly having one or more tabs; a current collector connected to the tabs of the electrode assembly; a cover assembly including terminal components connected to the current collector; and a housing housing the electrode assembly and including an opening, the cover assembly being configured to cover the opening of the housing, the terminal components including terminals, supports, and insulating components, and being integrally molded by insert injection molding.

[0024] In one embodiment, the terminal may be cylindrical with a first height, and the bracket may be a hollow cylinder with a second height less than the first height and an internal channel. The insulating component may include: an inner support portion disposed between the outer surface of the terminal and the inner surface of the bracket; an outer support portion covering at least a portion of the outer surface of the bracket; and an extension portion connecting one end of the inner support portion and the outer support portion. At least a portion of the bracket may be inserted into the space formed by the inner support portion, the outer support portion, and the extension portion.

[0025] In one embodiment, the inner support portion may have a third height, the outer support portion may have a fourth height less than the third height, the fourth height of the outer support portion may be less than the second height of the bracket, the inner surface of the bracket may be configured to be in integral contact with the inner support portion of the insulating component, the outer surface of the bracket may be in contact with the outer support portion of the insulating component, and may include at least a portion of an exposed surface, the exposed surface of the bracket may be welded to the cover plate, and the other end of the outer support portion of the insulating component may be disposed on one side of the cover plate.

[0026] (III) Beneficial Effects According to one embodiment of this disclosure, a cover assembly for a secondary battery and a secondary battery including the cover assembly can be provided, which improves assemblability and productivity.

[0027] Furthermore, according to one embodiment of this disclosure, a cover assembly for a secondary battery with a simple structure and improved electrical characteristics, and a secondary battery including the same, can be provided. Attached Figure Description

[0028] Figure 1 This is a perspective view of a cover assembly according to an embodiment of the present disclosure.

[0029] Figure 2 yes Figure 1 An exploded 3D diagram.

[0030] Figure 3 It is shown Figure 1 The diagram of the upper surface.

[0031] Figure 4 It is shown Figure 1 A diagram of the terminal components.

[0032] Figure 5 It is along Figure 3 The cross-sectional view taken from line AA.

[0033] Figure 6 It is shown Figure 5 A diagram of the insulating components.

[0034] Figure 7 This is a diagram schematically illustrating the process of manufacturing a cover assembly according to an embodiment of the present disclosure.

[0035] Figure 8 This is a perspective view of a cover assembly according to another embodiment of the present disclosure.

[0036] Figure 9 This is a diagram illustrating an insulating component according to yet another embodiment of the present disclosure.

[0037] Figure 10 This is a schematic diagram illustrating a terminal component according to another embodiment of the present disclosure.

[0038] Figure 11 It is along Figure 10 A cross-sectional view taken from the BB line.

[0039] Figure 12 This is a diagram illustrating a secondary battery according to other embodiments of the present disclosure.

[0040] Figure 13 yes Figure 12 An exploded 3D diagram.

[0041] Explanation of reference numerals in the attached figures: 100: Cover assembly for secondary batteries; 110: Cover plate 120: Terminal component; 130: Exhaust component 140: Current collector; 150: Insulating sheet Detailed Implementation

[0042] The structural or functional descriptions of embodiments disclosed in this specification or application are merely illustrative for the purpose of illustrating embodiments based on the technical concept of this disclosure. Embodiments based on the technical concept of this disclosure may be implemented in various forms other than those disclosed in this specification or application, and should not be construed as limiting the technical concept of this disclosure to the embodiments described in this specification or application.

[0043] Figure 1 This is a perspective view of a cover assembly according to an embodiment of the present disclosure. Figure 2 yes Figure 1 An exploded 3D diagram. Figure 3 It is shown Figure 1 The diagram of the upper surface. Figure 4 It is shown Figure 1 A diagram of the terminal components. Figure 5 It is along Figure 3 The cross-sectional view taken from line AA. Figure 6 It is shown Figure 5 A diagram of the insulating components.

[0044] Reference Figures 1 to 4 According to one embodiment of the present disclosure, a cover assembly 100 for a secondary battery may include: a cover plate 110 having one or more openings 111; and one or more terminal components 120 inserted into the openings 111 and exposed from one side of the cover plate 110. The terminal component 120 includes a terminal 121, a bracket 123, and an insulating component 125, and may be integrally molded by insert injection molding.

[0045] The secondary battery may include a housing having one or more openings, a cover assembly 100 covering the opening of the housing, and an electrode assembly and an electrolyte housed within the housing.

[0046] The electrode assembly may include a positive electrode, a negative electrode, and a separator disposed between the positive and negative electrodes. The electrode assembly may be housed within the casing along with an ion-conducting electrolyte. The positive and negative electrodes may be electrically connected to the terminal component 120 of the cover assembly 100 via a current collector or the like. The terminal component 120 is exposed to the outside within the secondary battery and functions as the positive and negative terminals.

[0047] Furthermore, when using solid electrolytes or polymeric gel electrolytes, the diaphragm can be omitted from the electrode assembly. The electrode assembly consists of a positive electrode and a negative electrode, and the solid electrolyte or polymeric gel electrolyte can be disposed between the positive and negative electrodes.

[0048] Typically, secondary battery cover assemblies form the positive and negative terminals by separately using plate-shaped external terminals, rivet-shaped internal terminals, and one or more washers, and assembling them together. Specifically, a method is used where the rivet-shaped internal terminal is connected to a current collector connected to the positive or negative terminal, and then inserted into the external terminal inside the housing, where external force is applied to deform and fix it. In this configuration, the external terminal is located on the outer surface of the cover, and the internal terminal is located on the inner surface. Connecting the internal and external terminals in this manner has resulted in numerous problems and low productivity due to the increased number of individual components. Furthermore, managing the operator's skill level is necessary, and sealing defects caused by assembly tolerances frequently occur, causing further problems.

[0049] On the other hand, the secondary battery cover assembly 100 according to embodiments of the present disclosure, by adopting a new structure, reduces the number of components constituting the cover assembly 100 and simplifies the assembly method, thereby improving productivity and process efficiency. Furthermore, the secondary battery cover assembly 100 according to embodiments of the present disclosure blocks and / or reduces leakage paths between the components constituting the cover assembly 100, thereby improving sealing performance, which in turn improves the electrochemical characteristics of the secondary battery.

[0050] The cover plate 110 can be provided in a form corresponding to the opening face of the housing. If the housing is cylindrical, the cover plate 110 can be circular. If the housing is prismatic, the cover plate 110 can be quadrilateral. If the housing has more than one opening face, the cover plate 110 can be provided according to the number of opening faces of the housing. For example, if the housing has two opening faces, two cover plates 110 can be provided. Although the case of a prismatic housing with one opening face is shown in this disclosure, it is not limited to this.

[0051] The cover plate 110 is provided with one or more openings 111, through which at least a portion of the terminal component 120 is exposed to the outside. Specifically, openings 111 may be provided on one side and the other side of the cover plate 110, and the terminal component 120 may be disposed in the openings 111 respectively, thereby functioning as a positive terminal and a negative terminal.

[0052] The secondary battery cover assembly 100 may further include: an exhaust component 130 disposed on the cover plate 110; one or more current collectors 140 connected to the terminal component 120 on the other side of the cover plate 110; and an insulating sheet 150 disposed between the current collector 140 and the cover plate 110.

[0053] The cover plate 110 may further include a vent portion 112, and the venting component 130 is disposed in the vent portion 112. The vent portion 112 may be located at the center of the cover plate 110. The venting component 130 may be made of metal and may include a portion with relatively low strength that can be destroyed by external force. When the pressure inside the housing exceeds a predetermined value, the venting component 130 is destroyed, resulting in an intentional leak, thus preventing the secondary battery from progressing to fire or explosion.

[0054] The current collector 140 may be made of a material capable of electrical connection. The current collector 140 functions as a channel to transmit the current generated in the electrode assembly to the outside. The current collector 140 may include a first current connection portion 141 connected to the terminal component 120 and a second current connection portion 142 connected to the positive or negative electrode of the electrode assembly.

[0055] In this disclosure, the first current connection portion 141 and the second current connection portion 142 can be connected vertically. Specifically, the longitudinal section of the current collector 140 can be in the shape of a "U". In the current collector 140, the connection configuration of the first and second current connection portions 141 and 142 can be configured in various ways and is not limited to this.

[0056] The insulating sheet 150 can be disposed on the other side of the cover plate 110. The insulating sheet 150 can be made of an insulating material and can be provided in a form corresponding to the cover plate 110. When the cover plate 110 is quadrilateral, the insulating sheet 150 can also be quadrilateral. By insulating the cover plate 110, the insulating sheet 150 can prevent electrical short circuits between the cover plate 110 and electrode assemblies disposed inside the housing.

[0057] The insulating sheet 150 may include a first hole 151 and a second hole 152. The first hole 151 is located at a position corresponding to the opening 111 of the cover plate 110, and the second hole 152 may be located at a position corresponding to the vent 112 of the cover plate 110.

[0058] One side of the terminal component 120 can be exposed from one side of the cover plate 110, and the other side of the terminal component 120 can be connected to the current collector 140. Specifically, the terminal component 120 can be inserted into the opening 111 on one side of the cover plate 110, and can be electrically connected to the current collector 140 through the first hole 151 of the insulating sheet 150. Specifically, the terminal component 120 does not require additional connecting parts and can be directly connected to the current collector 140.

[0059] The first hole 151 may have an area smaller than the maximum cross-sectional area of ​​the terminal component 120. Furthermore, the first hole 151 may have an area smaller than the opening 111. Specifically, when the terminal component 120 is inserted through the opening 111, only the terminals 121 and insulating components 125 of the terminal component 120 can pass through the first hole 151. More specifically, only the terminals 121 and insulating components 125 are inserted into the terminal component 120, and the support 123 may be configured to be disposed on one side of the insulating sheet 150.

[0060] Furthermore, the exhaust component 130 provided in the exhaust port 112 is exposed through the second hole 152, thereby enabling it to respond sensitively to the internal pressure of the housing.

[0061] The cross-section of the terminal component 120 can be either circular or elliptical. The fact that the terminal component 120 has a cross-section that is either circular or elliptical facilitates the assembly of the secondary battery cover assembly 100.

[0062] Reference Figure 4 The terminal 121 is cylindrical, the bracket 123 is a hollow cylinder with an internal channel, and the insulating component 125 may be located between the terminal 121 and the bracket 123.

[0063] The terminal 121 is disposed on the cover plate 110 and can function as either a positive or negative terminal. The bracket 123 can enhance the rigidity of the terminal 121 and fix the terminal 121 to the cover plate 110.

[0064] The terminal 121 can be electrically connected to the current collector 140, and the bracket 123 can be fixed to the cover plate 110. The terminal 121 and the bracket 123 are made of a conductive material such as metal, but an insulating component 125 is placed between the terminal 121 and the bracket 123 to prevent current from flowing between them. Specifically, the terminal 121 is electrically connected to the electrode assembly via the current collector 140, and the bracket 123 can be connected to the cover plate 110.

[0065] An insulating component 125 is provided between the terminal 121 and the bracket 123, and an insulating sheet 150 is provided between the bracket 123 and the current collector 140, thereby cutting off the electrical connection between the terminal 121 and the cover plate 110, and also cutting off the electrical connection between the bracket 123 and the current collector 140. In the secondary battery cover assembly 100 according to an embodiment of the present disclosure, the terminal component 120 is securely fixed to the cover plate 110 of the cover assembly 100 by the bracket 123, and can remain insulated relative to the cover plate 110.

[0066] At least one of the outer surface 121a of the terminal 121 and the inner peripheral surface 123a of the support 123 may include a surface roughening portion. By including a surface roughening portion on at least one of the outer surface 121a of the terminal 121 and the inner peripheral surface 123a of the support 123, the surface area of ​​the terminal 121 and the support 123 can be increased, thereby increasing the contact area with the insulating member 125. Furthermore, the terminal 121 and the support 123 are made of metal, and the insulating member 125 can be made of polymer resin or the like. By providing a surface roughening portion on at least one of the outer surface 121a of the terminal 121 and the inner peripheral surface 123a of the support 123 to provide frictional force with the insulating member 125, the bonding force of the terminal member 120 can be increased.

[0067] At least one of the outer surface 121a of the terminal 121 and the inner peripheral surface 123a of the bracket 123 may include threads. Specifically, the surfaces of the terminal 121 and the inner peripheral surface 123a of the bracket 123 that are opposite to each other may be provided with threads.

[0068] The terminal component 120 can be formed by insert injection molding. Specifically, after placing the terminal 121 and the support 123 in an insert injection mold, the terminal 121, the support 123, and the insulating component 125 can be integrally molded by adding a substance such as a polymer resin. At this time, the bonding force between the outer surface 121a of the terminal 121 and the insulating component 125, and between the inner peripheral surface 123a of the support 123 and the insulating component 125, can be improved, thereby exhibiting high airtightness.

[0069] The insulating component 125 may contain a crystalline resin among polymer resins. Because the insulating component 125 is made of a crystalline resin, the strength of the terminal component 120 can be improved, and the bonding force between the terminal 121 and the support 123 can be further improved.

[0070] The crystalline resin may include one or more selected from polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), polyether etherketone (PEEK), polyamide (PA), polyethylene terephthalate (PET), polyoxymethylene (POM), polypropylene (PP), polyethylene (PE), polyimide (PI), and maleic anhydride grafted polypropylene (PP-g-MA).

[0071] The insulating component 125 can be used by equipping the polymer resin with functional groups.

[0072] Furthermore, to enhance strength, the insulating component 125 can be used by mixing fillers into the polymer resin. The fillers may include one or more of glass fiber, carbon fiber, and aramid fiber.

[0073] The terminal 121 has a circular cross-section, and its average diameter can be set to a first diameter r1. The bracket 123 has an annular cross-section, and its average inner diameter can be set to a second diameter r2. The first diameter r1 can be set to 5 mm to 50 mm. If the first diameter r1 is less than 5 mm, problems may occur due to excessive resistance when electrically connecting to external devices. If it exceeds 50 mm, an electrical short circuit may occur during the manufacturing of the cover assembly 100, or interference with the exhaust section may occur.

[0074] The second diameter r2 can be 1 mm to 10 mm larger than the first diameter r1. If the difference between the second diameter r2 and the first diameter r1 (r2-r1) is less than 1 mm, the insulation provided by the insulating component 125 will decrease, and numerous defects and problems will occur during the insert injection molding process of the terminal component 120. Furthermore, if the difference between the second diameter r2 and the first diameter r1 (r2-r1) exceeds 10 mm, phenomena such as poor injection shrinkage will occur, resulting in a decrease in the bonding force between the insulating component 125 and the terminal 121 and the support 123, and causing problems.

[0075] Reference Figure 5 and Figure 6 According to an embodiment of the present disclosure, one side of the terminal component 120 can be exposed from one side of the cover plate 110, and the other side of the terminal component 120 can correspond to the other side of the cover plate 110. In the terminal component 120, the insulating member 125 is located between the terminal 121 and the bracket 123, and can be configured to cover at least a portion of the bracket 123. Specifically, the bracket 123 is not exposed on one side of the terminal component 120, and the bracket 123 can only be exposed on the other side of the terminal component 120. More specifically, one side of the terminal component 120 is provided with the terminal 121 and the insulating member 125, and the other side of the terminal component 120 can be provided with the terminal 121, the bracket 123, and the insulating member 125.

[0076] The insulating component 125 includes one or more recessed portions 120a, which may be disposed on one side of the terminal component 120. Multiple recessed portions 120a may be provided. According to this embodiment, the terminal component 120 may be formed by insert injection molding. The recessed portions 120a of the insulating component 125 may be provided for separating the terminal component 120 from the insert injection mold during insert injection molding. Specifically, the recessed portions 120a may be provided along the circular edge of the insulating component 125, and four may be provided. By providing four recessed portions 120a, the terminal component 120 can be effectively separated from the insert injection mold, and damage to the appearance of the insulating component 125 within the terminal component 120 can be prevented.

[0077] The insulating component 125 includes a recessed placement portion 126 along its edge, into which at least a portion of the bracket 123 can be inserted. Because the bracket 123 is inserted into the placement portion 126, only the terminal 121 and the insulating component 125 are exposed on one side of the terminal component 120, allowing the terminal component 120 to be reliably used as the positive or negative terminal of a target without electrical short circuits.

[0078] The terminal 121 is cylindrical with a first height h1, and the bracket 123 may be a hollow cylinder with a second height h2 that is less than the first height h1 and has a channel formed inside.

[0079] The insulating component 125 includes: an inner support portion 125a disposed between the outer surface of the terminal 121 and the inner surface of the bracket 123; an outer support portion 125b covering at least a portion of the outer surface of the bracket 123; and an extension portion 125c connecting one end of the inner support portion 125a and the outer support portion 125b, wherein at least a portion of the bracket 123 can be inserted into the space formed by the inner support portion 125a, the outer support portion 125b, and the extension portion 125c. The space formed by the inner support portion 125a, the outer support portion 125b, and the extension portion 125c can be a placement portion 126.

[0080] The internal support portion 125a has a third height h3, and the external support portion 125b may have a fourth height h4 that is smaller than the third height h3. The fourth height h4 of the external support portion 125b may be smaller than the second height h2 of the bracket.

[0081] The inner surface of the bracket 123 is configured to be in integral contact with the inner support portion 125a of the insulating component 125, and the outer surface of the bracket 123 is in contact with the outer support portion 125b of the insulating component 125, and may include at least a partially exposed surface S. The exposed surface S of the bracket 123 is welded to the cover plate 110, and the other end of the outer support portion 125b of the insulating component 125 may be disposed on one side of the cover plate 110.

[0082] After the terminal component 120 is inserted into the opening 111 of the cover plate 110, it can be fixed to the cover plate 110 by means of laser welding or the like. Specifically, the exposed surface S of the bracket 123 of the terminal component 120 that is exposed to the outside of the insulating component 125 can be connected to the opening 111 of the cover plate 110 by means of laser welding or the like.

[0083] In the terminal component 120 of the secondary battery cover assembly 100, a leakage path for venting air or the like can be formed by a first path between the terminal 121 and the insulating component 125, a second path between the support 123 and the insulating component 125, and a third path, i.e., the portion where the cover plate 110 is welded to the support 123. In this case, the first and second paths maintain airtightness through the surface bonding force between the insulating component 125 (made of polymer resin, etc.) and the terminal 121 and support 123 (made of metal).

[0084] In the secondary battery cover assembly 100 according to an embodiment of the present disclosure, surface roughness portions such as threads may be provided on the outer surface of the terminal 121 and the inner surface of the bracket 123. The surface roughness portions provided on the outer surface of the terminal 121 and the inner surface of the bracket 123 increase the surface area of ​​the terminal 121 and the bracket 123 in contact with the insulating member 125, thereby improving airtightness.

[0085] Furthermore, the surface roughness provided on the outer surface of the terminal 121 and the inner surface of the bracket 123 may include threads. Since the threads are formed laterally, they are formed perpendicular to the leakage path, increasing the length of the first and second paths, thereby further improving the airtightness of the first and second paths.

[0086] Regarding the third path, the other end of the external support portion 125b of the insulating component 125 can effectively prevent leakage through the third path by contacting one side of the cover plate 110.

[0087] In the cover assembly 100 according to an embodiment of the present disclosure, the terminal component 120 has a circular cross-section, which facilitates assembly. Furthermore, since it is not connected by assembling rivets or applying pressure, quality variations due to assembly tolerances can be prevented. Moreover, by using an integral terminal component 120, the cover assembly 100 according to an embodiment of the present disclosure can improve productivity and process efficiency.

[0088] The following content utilizes Figures 7 to 11 Another embodiment of this disclosure is involved. In the following embodiments, for those described above... Figures 1 to 6 If the composition is repeated in the description, the description will be omitted.

[0089] Figure 7 This is a diagram schematically illustrating the process of manufacturing a cover assembly according to an embodiment of the present disclosure.

[0090] Reference Figure 7 The cover assembly 100 according to an embodiment of the present disclosure can be manufactured in the following order.

[0091] A cylindrical terminal 121 and an annular support 123 are prepared, and a surface roughening portion can be formed on at least one of the outer surface of the terminal 121 and the inner surface of the support 123. The surface roughening portion may include threads, and may be provided on both the outer surface of the terminal 121 and the inner surface of the support 123, such that the threads provided on the terminal 121 and the support 123 are opposite to each other.

[0092] Using an insert injection molding mold, an integral terminal component 120 can be formed, which connects the terminal 121 and the bracket 123 through an insulating component 125.

[0093] Furthermore, at least one of the following stages—simultaneous with, before, and after the terminal component 120—a cover plate 110 and an exhaust component 130 may be prepared, and the exhaust component 130 may be incorporated into the exhaust port portion of the cover plate 110.

[0094] The terminal component 120 can be installed in the opening of the cover plate 110 where the exhaust component 130 is located. In this case, the terminal component 120 can be fixed to the cover plate 110 by means of laser welding or the like.

[0095] An insulating sheet 150 may be provided on the lower part of the cover plate 110. The insulating sheet 150 is provided with a first hole and a second hole, etc. The lower surface of the terminal component 120 can be exposed through the first hole, and the exhaust component 130 can be exposed through the second hole.

[0096] The terminal component 120 can be connected to the current collector 140. The current collector 140 can be connected to the positive and negative terminals of the electrode assembly, respectively. When connected to the positive terminal, the terminal component 120 can be used as a positive terminal, and when connected to the negative terminal, the terminal component 120 can be used as a negative terminal.

[0097] Figure 8 This is a perspective view of a cover assembly according to another embodiment of the present disclosure.

[0098] Reference Figure 8 According to embodiments of the present disclosure, a secondary battery cover assembly 200 may include a cover plate 210, one or more terminal components 220 disposed on the cover plate 210, and a vent 230. Furthermore, one side of the terminal component 220 may be exposed from one side of the cover plate 210, and the other side of the terminal component 220 may be connected to a current collector 240.

[0099] The cross-section of the terminal component 220 can be at least one of a circle and an ellipse. Specifically, the terminal component 220 can be elliptical. When the width of the cover plate 210 is narrow, the diameter of the terminal component 220 can be reduced. In this case, since the terminal component 220 according to this embodiment is elliptical, while reducing the diameter of the terminal component 220 in the width direction of the cover plate 210, the diameter of the terminal component 220 in the length direction of the cover plate 210 can be increased, thereby increasing the surface area of ​​the terminal component 220. By increasing the surface area of ​​the terminal component 220, welding between the busbar and the terminal component 220 becomes easier, and current flow becomes smoother.

[0100] Figure 9 This is a diagram illustrating an insulating component according to yet another embodiment of the present disclosure.

[0101] Reference Figure 9 In the terminal component 220 according to an embodiment of the present disclosure, the terminal, the bracket, and the insulating component 325 can be formed by insert injection molding. The insulating component 325 may include: an inner support portion 325a disposed between the terminal and the bracket; an outer support portion 325b covering at least a portion of the outer surface of the bracket; and an extension portion 325c connecting the inner support portion 325a and the outer support portion 325b. In the insulating component 325, the longitudinal section of the inner support portion 325a, the outer support portion 325b, and the extension portion 325c may be U-shaped, and the other end of the outer support portion 325b may further include a friction surface 326.

[0102] During the manufacturing of the terminal component, the friction surface 326 can be formed by locally injecting a high-friction coefficient polymer resin into the mold during insert injection molding. Alternatively, the friction surface 326 may include a surface roughening portion formed by physical or chemical etching of the other end of the external support portion 325b after the terminal component has been manufactured by insert injection molding. The friction surface 326 can provide relatively high friction only to the other end of the external support portion 325b without altering the overall physical properties of the insulating component 325.

[0103] During the process of inserting the terminal component into the opening of the cover plate and assembling it, the other end of the external support 325b may come into contact with one side of the cover plate. According to this embodiment, the insulating component 325 may further include a friction surface 326 at the other end of the external support 325b, which can improve the airtightness between the external support 325b and the cover plate.

[0104] Figure 10This is a schematic diagram illustrating a terminal component according to another embodiment of the present disclosure. Figure 11 It is along Figure 10 A cross-sectional view taken from the BB line.

[0105] Reference Figure 10 and Figure 11 According to an embodiment of the present disclosure, the terminal component 420 may include a terminal 421, a support 423, and an insulating component 425 between the terminal 421 and the support 423. The terminal component 420 may be manufactured by insert molding of separately prepared terminals 421 and supports 423, and the insulating component 425 may be formed of a polymer resin or the like during the insert molding process.

[0106] In the terminal component 420 according to an embodiment of the present disclosure, at least a portion of the terminal 421 and the bracket 423 may further include a functional layer 421a.

[0107] The functional layer 421a may be disposed on the surface of the terminal 421 or the bracket 423, or it may be disposed on both sides of the terminal 421 and the bracket 423. Furthermore, the functional layer 421a may be disposed on a portion of the surface of the terminal 421 or the bracket 423, or it may be disposed on the entire surface of the terminal 421 or the bracket 423.

[0108] In the following description, it will be explained that the functional layer 421a is disposed on one side of the terminal 421, but is not limited thereto.

[0109] Prior to the injection molding of the insert, the functional layer 421a can be formed by surface treatment of at least one of the terminal 421 and the support. The functional layer 421a may include at least one of one or more functional groups and one or more nanopores.

[0110] The terminal 421 or the support 423 is made of metal or the like, and the insulating component 425 can be made of polymer resin or the like. Because they are made of different materials, the interfacial adhesion between them can be relatively low. Conversely, the terminal component 420 according to the embodiments of this disclosure further includes the functional layer 421a on the terminal 421 or the support 423, thereby improving the adhesion between the terminal 421, the insulating component 425, and the support 423, and further improving the airtightness of the terminal component 420.

[0111] The functional layer 421a may include at least one of one or more functional groups and one or more nanopores. The functional layer 421a may be formed by surface treatment such as a surface functionalization process or a surface etching process implemented using chemical substances.

[0112] The one or more functional groups can be chemically bonded to the surface of the terminal 421 or the support 423, and can enhance interfacial adhesion through chemical bonding such as covalent bonds and hydrogen bonds formed with the insulating component 425 made of the polymer resin; physical interactions such as mechanical bonding and electrostatic attraction; and based on the surface energy affinity of the polar functional groups.

[0113] Furthermore, the one or more nanopores can be arranged on the surface of the terminal 421 or the support 423 in the form of multiple micropores. By inserting the tiny bumps and depressions generated by the nanopores into the insulating component 425 and increasing the surface area, the interfacial adhesion can be improved.

[0114] The functional group may include at least one of the following: hydroxyl (-OH), amino (-NH2), and epoxy (-COC-).

[0115] The surface treatment may include a first to a third surface treatment.

[0116] When the functional group is a hydroxyl group, the functional layer 421a can be formed by a first surface treatment.

[0117] The first surface treatment may include: after forming a chromium (Cr) film on the surface of the terminal 421 or the bracket 423, applying an adhesive to form an adhesive coating. Specifically, the functional layer 421a may include the chromium film formed by the first surface treatment and the adhesive coating.

[0118] The chromium film may comprise chromium(III) hydroxide (Cr(OH)3) or chromium oxide (Cr2O3). The chromium(III) hydroxide (Cr(OH)3) can be formed by immersing the terminal 421 or the support 423 in an aqueous solution containing chromium (Cr) and controlling the pH. The chromium oxide (Cr2O3) can be formed by applying electrochemical oxidation (anodizing) or similar methods to the terminal 421 or the support 423.

[0119] The terminal 421 or the support 423 with the chromium film can be coated with an adhesive to form an adhesive coating. The adhesive may contain a polymer having hydroxyl groups. The adhesive may contain polyvinyl alcohol (PVA), polyurethane, and polyethylene glycol (PEG), etc.

[0120] Specifically, the first surface treatment can be implemented in the following manner.

[0121] After electrolytic degreasing of the terminal 421 or the support 423, a first water wash can be performed. A chromium film is formed on the terminal 421 or the support 423 after the first water wash, and a second water wash can be performed. After the second water wash, the adhesive is applied to the terminal 421 or the support 423 to form an adhesive coating, and drying is performed after a third water wash.

[0122] The terminal 421 or the bracket 423, having undergone the first surface treatment and having the chromium film and adhesive coating applied, can be manufactured as a terminal component 420 by insert injection molding together with a polymer resin.

[0123] The terminal 421 or the support 423, which is provided with the chromium film and the adhesive coating, is placed in an insert injection molding mold. Activated polymer resin, either alone or in mixture with the activated polymer resin, is added to the insert injection molding mold, and the terminal component 420 is manufactured by insert injection molding. The polymer resin or the activated polymer resin can be inserted between the terminal 421 and the support 423 through insert injection molding, thereby becoming an insulating component 425.

[0124] The activated polymer resin can be prepared by activating the polymer resin. The polymer resin comprises polypropylene (PP), and the activated polymer resin may comprise maleic anhydride grafted polypropylene (PP-g-MA) prepared by adding maleic anhydride to polypropylene (PP).

[0125] In the terminal component 420, a chromium film and an adhesive coating are formed on the terminal 421 or the support 423 through the first surface treatment. The hydroxyl groups (-OH) contained in the adhesive coating can exhibit high bonding strength with the maleic anhydride-grafted polypropylene (PP-g-MA).

[0126] When the functional group is amino, the functional layer 421a can be formed by a second surface treatment.

[0127] The second surface treatment may include: pretreating the surface of the terminal 421 or the support 423 with a pH-controlled solution, followed by treatment with a first silane coupling agent. Specifically, the functional layer 421a may contain amino groups formed by the second surface treatment.

[0128] The pretreatment may include immersing the terminal 421 or the support 423 in a pH-controlled solution. The pH-controlled solution may include treatment with an acidic or alkaline solution.

[0129] The pretreated terminal 421 or the support 423 can be coated with a silane coupling agent. The silane coupling agent may contain an amino-based silane. The amino-based silane may include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrialkoxysilane, etc.

[0130] Specifically, the second surface treatment can be implemented in the following manner.

[0131] After electrolytic degreasing of the terminal 421 or the support 423, a first water wash can be performed. After pretreatment with the acidic or alkaline solution on the terminal 421 or the support 423 after the first water wash, a first silane coupling agent can be coated. The terminal 421 or the support 423 coated with the first silane coupling agent can be dried after a second water wash.

[0132] The first silane coupling agent can be used after dilution with ethanol and water. The first silane coupling agent can be used after being diluted with the ethanol and water to a concentration of 1 wt% to 2 wt%.

[0133] The terminal 421 or the support 423, having undergone the second surface treatment and formed a first silane coating with the first silane coupling agent, can be injection molded together with a polymer resin to be manufactured as a terminal component 420.

[0134] The terminal 421 or the support 423, with a first silane coating formed by the first silane coupling agent, is placed into an insert injection molding mold. An activated polymer resin, prepared by activating a polymer resin, is added alone or as a mixture of the activated polymer resin and the polymer resin to the insert injection molding mold. The terminal component 420 can then be manufactured by insert injection molding. The polymer resin or the activated polymer resin can be inserted between the terminal 421 and the support 423 to form an insulating component 425.

[0135] The activated polymer resin can be provided by introducing carboxyl groups (-COOH) into the polymer resin. The activated polymer resin can be provided by copolymerizing the polymer resin with a monomer having carboxyl groups, or by subjecting the polymer resin to oxidation solution treatment with strong acids or peroxides, plasma treatment, UV / ozone treatment, etc.

[0136] Furthermore, the polymer resin may further include fillers. The fillers may comprise one or more of glass fiber, carbon fiber, and aramid fiber.

[0137] In the terminal component 420, a first silane coating is formed on the terminal 421 or the support 423 by the second surface treatment. The amino groups (-NH2) contained in the first silane coating can exhibit high binding strength by forming amide bonds (-CO-NH-) with the carboxyl groups provided in the activated polymer resin.

[0138] As an alternative, the polymer resin can be replaced with a filler incorporating carboxyl groups, and then incorporated into the insert injection mold. The filler incorporating carboxyl groups can be provided by surface treatment with a carboxyl derivative. The carboxyl groups provided by the filler incorporating carboxyl groups can function in the same or similar way as the carboxyl groups in the activated polymer resin.

[0139] When the functional group is an epoxy group, the functional layer 421a can be formed by a third surface treatment.

[0140] The third surface treatment may include: pretreating the surface of the terminal 421 or the support 423 with a pH-controlled solution, followed by treatment with a second silane coupling agent. Specifically, the functional layer 421a may contain epoxy groups formed by the third surface treatment.

[0141] The third surface treatment can be performed in the same way as the second surface treatment, but a second silane coupling agent can be used instead of the first silane coupling agent. The second silane coupling agent may comprise glycidoxypropyltrimethoxysilane (GPTMS).

[0142] Through the third surface treatment, the terminal 421 or the support 423 may be provided with a second silane coating formed by coating the second silane coupling agent. The second silane coating may provide epoxy groups.

[0143] In the terminal component 420, a second silane coating is formed on the terminal 421 or the support 423 by the third surface treatment. The epoxy groups (-COC-) contained in the second silane coating are combined with the carboxyl groups (-COO-CH2-CH(OH)-) provided in the activated polymer resin, which can exhibit high bonding strength.

[0144] Figure 12 This is a diagram illustrating a secondary battery according to other embodiments of the present disclosure. Figure 13 yes Figure 12 An exploded 3D diagram.

[0145] Reference Figure 12 and Figure 13 According to embodiments of the present disclosure, the cover assembly 100 can be assembled with the housing 1100 to form a secondary battery 1000.

[0146] The secondary battery 1000 may include: an electrode assembly 1200 having one or more tabs 1210 and 1220; a current collector 140 connected to the tabs 1210 and 1220 of the electrode assembly 1200; a cover assembly 100 including a terminal component 120 connected to the current collector 140; and a housing 1100 accommodating the electrode assembly 1200 and including an opening.

[0147] The housing 1100 has an internal accommodating space 1100a, within which the electrode assembly 1200 can be accommodated. The electrode assembly 1200 may include a negative electrode and a positive electrode, and the tabs 1210 and 1220 may include a negative electrode tab 1210 connected to the negative electrode and a positive electrode tab 1220 connected to the positive electrode.

[0148] The cover assembly 100 can be configured to cover the opening of the housing 1100. Specifically, when the housing 1100 has one opening, there can be one cover assembly 100; when the housing 1100 has two openings, there can be two cover assemblies 100.

[0149] The terminal component 120 includes terminals, a bracket, and an insulating component, and can be integrally molded by insert injection molding. The cover assembly 100 may further include: a cover plate 110, which is plate-shaped and configured to correspond to the opening surface of the housing 1100; an exhaust component 130 disposed on the cover plate 110; and a current collector 140 connected to the terminal component 120 on the lower side of the cover plate 110.

[0150] When the current collector 140 connected to the terminal component 120 is connected to the negative electrode tab 1210, the terminal component 120 functions as a negative electrode; when connected to the positive electrode tab 1220, it functions as a positive electrode.

[0151] The current collector 140, which is electrically connected to the negative electrode tab 1210, can be connected to the terminal component 120, so that the terminal component 120 functions as a negative terminal; when the current collector 140 is electrically connected to the positive electrode tab 1220, the terminal component 120 functions as a positive terminal.

[0152] The terminal 121 is cylindrical with a first height h1, and the bracket 123 may be a hollow cylinder with a second height h2 less than the first height h1 and an internal channel (see [reference]). Figure 5 ).

[0153] The insulating component 125 includes: an inner support portion 125a disposed between the outer surface of the terminal 121 and the inner surface of the bracket 123; an outer support portion 125b covering at least a portion of the outer surface of the bracket 123; and an extension portion 125c connecting one end of the inner support portion 125a and the outer support portion 125b, wherein at least a portion of the bracket 123 can be inserted into the space formed by the inner support portion 125a, the outer support portion 125b, and the extension portion 125c (see [link to documentation]). Figure 5 ).

[0154] The bracket 123 is separated from the terminal 121 by the insulating member 125, thereby maintaining electrical insulation between the bracket 123 and the terminal 121. Furthermore, by inserting the bracket 123 into the space formed by the inner support portion 125a, the outer support portion 125b, and the extension portion 125c, interference that may occur due to the bracket 123 during electrical connection of the terminal 121 can be prevented, and the terminal 121 can be stably fixed to the cover plate 110 by the bracket 123 (see [link to documentation]). Figure 5 ).

[0155] Furthermore, the inner support portion 125a has a third height h3, and the outer support portion 125b may have a fourth height h4 that is smaller than the third height h3. The fourth height h4 of the outer support portion 125b is set to be smaller than the second height h2 of the bracket 123. The inner surface of the bracket 123 is configured to be in integral contact with the inner support portion 125a of the insulating member 125, and the outer surface of the bracket 123 is in contact with the outer support portion 125b of the insulating member 125, and may include at least a partially exposed surface. The exposed surface of the bracket 123 is welded to the cover plate 110, and the other end of the outer support portion 125b of the insulating member 125 may be mounted on one side of the cover plate 110 (see [reference]). Figure 5 ).

[0156] The terminals, supports, and insulating components constituting the terminal component 120, by having the aforementioned height relationship, improve the strength of the integrally molded terminal component 120 and effectively eliminate leakage paths of the secondary battery formed through the terminal component 120. Furthermore, in the terminal component 120, the terminals and supports are respectively provided with threads, which increase the contact area with the insulating components, thereby further improving the airtightness of the secondary battery.

[0157] exist Figure 12 and Figure 13 Although the housing 1100 is shown as having an opening on one side, it can be open on two sides and is not limited to this.

[0158] As an alternative, when the housing is open on both sides, the negative electrode tab of the electrode assembly can be located on one side of the housing, and the positive electrode tab of the electrode assembly can be located on the other side of the housing. In this case, the cover assembly can be provided with a terminal component and connected to one side and the other side of the housing respectively.

[0159] In the secondary battery 1000 of this disclosure, at least a portion of the terminal 121 and the support 123 constituting the terminal component 120 may further include a functional layer.

[0160] Prior to the injection molding of the insert, the functional layer can be formed by surface treatment of at least one of the terminal 121 and the support 123. The functional layer may contain at least one of one or more functional groups and one or more nanopores.

[0161] In embodiments of this disclosure, the terminal 121 and the support 123 are made of metal, and the insulating component 125 between the terminal 121 and the support 123 may be made of a polymer resin. By further including a functional layer in at least a portion of the terminal 121 and the support 123, the adhesion to the insulating component 125 made of a different material can be further improved, and the airtightness of the secondary battery 1000 can be enhanced.

[0162] Those skilled in the art to which this disclosure pertains will understand that this disclosure may be implemented in other specific forms without altering its technical concept or essential features. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not limiting. The scope of this disclosure is defined by the claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning, scope, and equivalents of the claims should be construed as being included within the scope of this disclosure.

Claims

1. A cover assembly for a secondary battery, comprising: Cover plate, having one or more openings; and One or more terminal components are inserted into the opening and exposed from one side of the cover plate. The terminal component includes terminals, brackets, and insulating components, and is integrally molded by insert injection molding.

2. The cover assembly for a secondary battery according to claim 1, wherein, The terminal component has a cross-section that is either circular or elliptical.

3. The cover assembly for a secondary battery according to claim 1, wherein, The terminal is cylindrical. The support is a hollow cylinder with internal channels. The insulating component is located between the terminal and the bracket.

4. The cover assembly for a secondary battery according to claim 1, wherein, One side of the terminal component is exposed from one side of the cover plate. The terminal component has the terminal and the insulating component on one side. The terminal component is provided with the terminal, the bracket, and the insulating component on the other side. The insulating component includes one or more recessed portions, which are disposed on one side of the terminal component.

5. The cover assembly for a secondary battery according to claim 3, wherein, The insulating component includes a recessed portion along the edge of the insulating component. At least a portion of the bracket is inserted into the placement portion.

6. The cover assembly for a secondary battery according to claim 3, wherein, At least one of the outer surface of the terminal and the inner circumferential surface of the bracket includes a surface rough portion.

7. The cover assembly for a secondary battery according to claim 3, wherein, At least one of the outer surface of the terminal and the inner circumferential surface of the bracket includes threads.

8. The cover assembly for a secondary battery according to claim 1, wherein, The terminal is cylindrical with a first height. The support is a hollow cylinder with a second height less than the first height and an internal channel. The insulating component includes: An internal support portion is disposed between the outer surface of the terminal and the inner surface of the bracket; An external support portion, covering at least a portion of the outer surface of the bracket; and An extension portion, connecting one end of the inner support portion and the outer support portion. At least a portion of the bracket is inserted into the space formed by the inner support, the outer support, and the extension.

9. The cover assembly for a secondary battery according to claim 8, wherein, The internal support portion has a third height, and the external support portion has a fourth height that is smaller than the third height. The fourth height of the external support is less than the second height of the bracket. The inner surface of the bracket is configured to be in integral contact with the inner support portion of the insulating component, the outer surface of the bracket is in contact with the outer support portion of the insulating component, and includes at least a portion of the exposed surface.

10. The cover assembly for a secondary battery according to claim 9, wherein, The exposed surface of the bracket is welded to the cover plate. The other end of the external support of the insulating component is mounted on one side of the cover plate.

11. The cover assembly for a secondary battery according to claim 10, wherein, The longitudinal sections of the internal support, the external support, and the extension are in the shape of a "∩". The other end of the external support further includes a friction surface.

12. The cover assembly for a secondary battery according to claim 1, further comprising: An exhaust component is provided on the cover plate; One or more current collectors are connected to the terminal component on the other side of the cover plate; as well as An insulating sheet is placed between the current collector and the cover plate. The cover plate further includes a vent portion, and the venting component is disposed in the vent portion. One side of the terminal component is exposed from one side of the cover plate, and the other side of the terminal component is connected to the current collector.

13. The cover assembly for a secondary battery according to claim 1, wherein, At least a portion of the terminal and the bracket further includes a functional layer.

14. The cover assembly for a secondary battery according to claim 13, wherein, The functional layer is formed by surface treating at least one of the terminals and the bracket prior to the injection molding of the insert. The functional layer contains at least one of one or more functional groups and one or more nanopores.

15. The cover assembly for a secondary battery according to claim 14, wherein, The functional group includes at least one of hydroxyl (-OH), amino (-NH2), and epoxy (-COC-).

16. A secondary battery, comprising: The electrode assembly has one or more electrode tabs; A current collector is connected to the tab portion of the electrode assembly; The cover assembly includes a terminal component connected to the current collector; as well as Housing, accommodating the electrode assembly and including an opening surface, The cover assembly is configured to cover the opening of the housing. The terminal component includes terminals, brackets, and insulating components, and is integrally molded by insert injection molding.

17. The secondary battery according to claim 16, wherein, The terminal is cylindrical with a first height. The support is a hollow cylinder with a second height less than the first height and an internal channel. The insulating component includes: An internal support portion is disposed between the outer surface of the terminal and the inner surface of the bracket; An external support portion, covering at least a portion of the outer surface of the bracket; and An extension portion, connecting one end of the inner support portion and the outer support portion. At least a portion of the bracket is inserted into the space formed by the inner support, the outer support, and the extension.

18. The secondary battery according to claim 17, wherein, The internal support portion has a third height, and the external support portion has a fourth height that is smaller than the third height. The fourth height of the external support is less than the second height of the bracket. The inner surface of the bracket is configured to be in integral contact with the inner support portion of the insulating component, and the outer surface of the bracket is in contact with the outer support portion of the insulating component, and includes at least a portion of an exposed surface. The exposed surface of the bracket is welded to the cover plate. The other end of the external support of the insulating component is mounted on one side of the cover plate.

19. The secondary battery according to claim 16, wherein, At least a portion of the terminal and the bracket further includes a functional layer.

20. The secondary battery according to claim 19, wherein, The functional layer is formed by surface treating at least one of the terminals and the bracket prior to the injection molding of the insert. The functional layer contains at least one of one or more functional groups and one or more nanopores.

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