O-ring for preventing leakage of electrolyte

Abstract

An O-ring according to an embodiment of the present invention comprises: a first part seated on a bead portion in which a battery housing is recessed inward; and a second part provided above the first part and configured to cover the upper surface of the battery housing.

Description

Electrolyte leakage prevention O-ring

[0001] The present invention relates to an O-ring for preventing electrolyte leakage.

[0002] This application claims priority to Korean Patent Application No. 10-2023-0096275, filed on July 24, 2023, and all contents disclosed in the specification and drawings of the said application are incorporated by reference into this application.

[0003] This application claims priority to Korean Patent Application No. 10-2024-0092210, filed on July 12, 2024, and all contents disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0004]

[0005] Secondary batteries, which boast high electrical properties such as high energy density and high applicability across a wide range of product categories, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) powered by electrical power sources. These batteries not only offer the primary advantage of dramatically reducing fossil fuel use but also produce no byproducts from energy use, attracting attention as a new energy source for environmental friendliness and energy efficiency.

[0006] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, i.e., unit battery cells, is approximately 2.5 V to 4.5 V. Therefore, when a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Furthermore, depending on the charge / discharge capacity required for the battery pack, a number of battery cells are connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage and / or charge / discharge capacity.

[0007] Meanwhile, when manufacturing cylindrical secondary batteries, the electrode assembly is inserted into the battery housing and then an electrolyte injection process is performed for activation. During this process, an O-ring is installed to prevent electrolyte leakage outside the battery housing. However, conventional O-rings have the problem of electrolyte leakage due to reduced leakage performance caused by contact with the battery housing.

[0008]

[0009] Accordingly, the present invention aims to solve the above problem by providing an O-ring that can prevent electrolyte from leaking outside of a battery housing when electrolyte is injected into a cylindrical battery cell.

[0010] More specifically, the present invention aims to increase sealing properties by expanding the contact area between the battery housing and the O-ring.

[0011] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0012]

[0013] An O-ring according to one embodiment of the present invention for solving the above-described problem comprises: a first part that is seated on a beaded portion into which a battery housing is inserted; and a second part that is provided above the first part and is configured to cover an upper surface of the battery housing.

[0014] In one aspect of the present invention, the first part may be configured in a cylindrical shape.

[0015] In another aspect of the present invention, the O-ring may have elasticity.

[0016] Preferably, the O-ring may include at least one of NBR, VMQ, FKM and FPM.

[0017] In another aspect of the present invention, the O-ring may include a liquid hole extending vertically through the center.

[0018] In one aspect of the present invention, the O-ring may have a groove into which a hopper capable of pressurizing the O-ring can be fitted.

[0019] In another aspect of the present invention, the outer surface of the first part may be configured to be spaced apart from the inner surface of the battery housing by a predetermined distance.

[0020] Preferably, the outer surface of the first part may be configured to be spaced apart from the inner surface of the battery housing by 0.2 to 0.8 mm.

[0021] In another aspect of the present invention, the lower surface of the second part may be configured to be spaced apart from the upper surface of the battery housing by a predetermined distance.

[0022] In one aspect of the present invention, the O-ring may include a pressure surface provided on the inside or outside of the O-ring and configured to be pressed downward by the hopper.

[0023] Preferably, when the pressurized surface is pressed downward, the first part may be configured to increase in width in the radial direction while being compressed in the vertical direction.

[0024] In another aspect of the present invention, when the pressurized surface is pressed downward, the second part may be configured to move downward and come into contact with the upper surface of the battery housing.

[0025] In another aspect of the present invention, when pressure is applied from the outside of the battery housing toward the beading portion of the battery housing, the O-ring can be configured to block the outside and the inside of the battery housing.

[0026] In another aspect of the present invention, the thickness of the first part can alternately increase and decrease along the circumferential direction.

[0027]

[0028] According to the present invention, when injecting electrolyte into a cylindrical battery cell, it is possible to prevent the electrolyte from leaking outside the battery housing.

[0029] Additionally, according to the present invention, the contact area between the battery housing and the O-ring can be expanded.

[0030] Accordingly, according to the present invention, the sealing performance of a battery cell can be improved when an electrolyte is injected.

[0031] However, the effects that can be obtained through the present invention are not limited to the effects described above, and other technical effects not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0032]

[0033] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0034] FIG. 1 is a drawing for explaining a battery cell according to one embodiment of the present invention.

[0035] Figure 2 is a cross-sectional perspective view of Figure 1.

[0036] Figure 3 is a cross-sectional view of the battery cell of Figure 1.

[0037] Figure 4 is a drawing for explaining a conventional O-ring.

[0038] Figure 5 is a drawing for explaining the state of a conventional O-ring before it is compressed.

[0039] Figure 6 is a drawing for explaining the state of a conventional O-ring after it has been compressed.

[0040] Figure 7 is a drawing for explaining an O-ring according to one embodiment of the present invention.

[0041] Figure 8 is a drawing for explaining the state of the O-ring of Figure 7 before it is compressed.

[0042] Figure 9 is an enlarged view of a portion of Figure 8.

[0043] Fig. 10 is a drawing for explaining the state after the O-ring of Fig. 7 is compressed.

[0044] Fig. 11 is a drawing for explaining an O-ring according to another embodiment of the present invention.

[0045] Fig. 12 is a drawing for explaining an O-ring according to another embodiment of the present invention.

[0046] Fig. 13 is a drawing for explaining an O-ring according to another embodiment of the present invention.

[0047]

[0048] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be interpreted as limited to their typical or dictionary meanings, and should be interpreted with meanings and concepts that conform to the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term to best explain his or her own invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

[0049] Additionally, to facilitate understanding of the invention, the attached drawings are not drawn to scale and some components may have exaggerated dimensions. Furthermore, identical components may be assigned the same reference numbers in different embodiments.

[0050] The statement that two compared objects are identical means "substantially identical." Therefore, "substantially identical" may include deviations considered low in the art, such as deviations of less than 5%. Furthermore, uniformity of a parameter over a given region may also mean uniformity on average.

[0051] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0052] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0053] Any configuration being placed "on (or below)" a component or "on (or below)" a component may mean not only that any configuration is placed in contact with the upper surface (or lower surface) of said component, but also that other configurations may intervene between said component and any configuration placed on (or below) said component.

[0054] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0055] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C to D", this means C or more and D or less, unless otherwise stated.

[0056]

[0057] FIG. 1 is a drawing for explaining a battery cell (1) according to one embodiment of the present invention, and FIG. 2 is a longitudinal cross-sectional perspective view of FIG. 1. FIG. 3 is a longitudinal cross-sectional view of the battery cell (1) of FIG. 1.

[0058] Referring to FIG. 1, a battery cell (1) according to one embodiment of the present invention includes an electrode assembly (10), a battery housing (20), and a current collector (30). The battery cell (1) may further include a housing cover (40) and / or a terminal (50) and / or a second current collector (60). The present invention is not limited by the shape of the battery, and is applicable to batteries of other shapes, such as square batteries.

[0059] The electrode assembly (10) includes a first non-coated portion (11) and a second non-coated portion (12). More specifically, the electrode assembly (10) has a structure in which the first electrode and the second electrode and the separator interposed therebetween are wound around a winding axis, with a separator interposed therebetween, to define a core and an outer circumferential surface. That is, the electrode assembly (10) applied to the present invention may be a jelly-roll type electrode assembly (10). The electrode assembly (10) may be wound around a winding center hole (H1). In this case, an additional separator may be provided on the outer circumferential surface of the electrode assembly (10) for insulation from the battery housing (20). The electrode assembly (10) may have a winding structure well known in the art without limitation. Meanwhile, in the present invention, the positive electrode active material coated on the positive electrode plate and the negative electrode active material coated on the negative electrode plate may be used without limitation as long as they are active materials known in the art.

[0060]

[0061] Referring to Fig. 1, the battery housing (20) is a roughly cylindrical receiver with an opening formed on one side, and is made of a conductive metal material. The side surface of the battery housing (20) and the lower surface located opposite the opening are typically formed as one piece. That is, the battery housing (20) typically has an open upper portion in the height direction and a closed lower portion. The lower surface of the battery housing (20) may have a roughly flat shape. The lower surface of the battery housing (20) may constitute an outer surface (20a) of the closed portion. In this case, the outer surface (20a) of the closed portion may function as a second electrode terminal.

[0062] The above battery housing (20) accommodates an electrode assembly (10) through an opening formed on one side in the height direction. The battery housing (20) can also accommodate an electrolyte through the opening. The upper surface (25) of the battery housing (20) constituting the opening can be bent horizontally through a crimping process after the electrolyte is subsequently injected.

[0063] The battery housing (20) may have a beading portion (21) formed at an end adjacent to an opening provided at the top of the battery housing (20). The battery housing (20) may further have a crimping portion (22) formed on the beading portion (21). The beading portion (21) has a shape in which the outer peripheral surface of the battery housing (20) is recessed to a predetermined depth. More specifically, the beading portion (21) may have a shape in which it is recessed inward in a region between the opening formed at one side of the battery housing (20) and the receiving portion that receives the electrode assembly (10).

[0064] The above beading portion (21) can provide a support surface on which at least a portion of the edge circumference of the current collector (30) to be described later can be secured and coupled. That is, at least a portion of the edge circumference of the current collector (30) of the present invention and / or the edge circumference of the housing cover (40) can be secured on the upper surface of the beading portion (21). In order to stably support at least a portion of the edge circumference of the current collector (30), the upper surface of the beading portion (21) can have a shape that extends along a direction substantially parallel to the lower surface of the battery housing (20), that is, along a direction substantially perpendicular to the side wall of the battery housing (20).

[0065]

[0066] Referring to FIGS. 1 to 3, a current collector (30) according to one embodiment of the present invention is accommodated inside a battery housing (20), is electrically connected to an electrode assembly (10), and is also electrically connected to a battery housing (20). That is, the current collector (30) electrically connects the electrode assembly (10) and the battery housing (20). The current collector (30) includes a support portion (31) positioned on one surface of the electrode assembly (10), a tab coupling portion (32) extending from the support portion (31) and coupled to a first non-conductive portion (11), and a housing coupling portion (33) extending from the support portion (31) and coupled to an inner surface of the battery housing (20). The current collector (30) may include a current collector hole (H2) in the center for injecting an electrolyte.

[0067] The housing coupling portion (33) may include a contact portion (33a) coupled to the inner surface of the battery housing (20) and a connection portion (33b) connecting the support portion (31) and the contact portion (33a). In one aspect of the present invention, the first tab coupling portion (32) may have a width greater than the connection portion (33b). In another aspect of the present invention, the contact portion (33a) may have a width greater than the connection portion (33b).

[0068] The above contact portion (33a) is coupled to the inner surface of the battery housing (20). Preferably, the contact portion (33a) may be coupled to the beading portion (21) of the battery housing (20). In this case, for stable contact and coupling, both the beading portion (21) and the contact portion (33a) may have a shape extending in a direction approximately parallel to the lower surface of the battery housing (20), i.e., in a direction approximately perpendicular to the side wall of the battery housing (20).

[0069]

[0070] Fig. 4 is a drawing for explaining a conventional O-ring (100). Fig. 5 is a drawing for explaining a state of a conventional O-ring (100) before compression, and Fig. 6 is a drawing for explaining a state of a conventional O-ring (100) after compression.

[0071] Typically, the battery housing (20) of a cylindrical battery cell undergoes an electrolyte injection process for activation after insertion of the electrode assembly (10). At this time, an O-ring (100) is installed to prevent electrolyte from leaking out of the battery housing (20) during electrolyte injection. However, in the case of a conventional O-ring (100), electrolyte leakage occurs due to a decrease in sealing performance, such as electrolyte leakage caused by contact with the battery housing (20).

[0072] For example, a conventional O-ring (100) is placed on the contact portion (33a) of the housing coupling portion (33) seated on the beading portion (21). At this time, when the O-ring (100) is compressed in the height direction of the battery cell, i.e., in the winding axis direction of the electrode assembly (10), the shape of the O-ring (100) is deformed due to elasticity. For example, when the O-ring (100) is pressed downward while seated on the beading portion (21) as shown in FIG. 5, the shape of the O-ring (100) is deformed as it is compressed in the vertical direction as shown in FIG. 6. As a result, as shown in FIG. 6, the area in which the O-ring (100) comes into contact with the current collector (30) and / or the battery housing (20) is reduced. That is, since the O-ring (100) comes into direct contact with the current collector (30) and / or the battery housing (20) after compression, it cannot completely seal the battery housing (20). Accordingly, the possibility of the electrolyte leaking to the outside when the electrolyte is injected becomes very high.

[0073] More specifically, referring to FIGS. 4 to 6, in the conventional O-ring (100), the first part (110) has a shape with extended legs rather than a cylindrical shape. At this time, when the O-ring (100) is pressed in the vertical direction, the leg portion of the first part (110) is lifted upward, and the first part (110) comes into linear contact with the current collector (30) and / or the battery housing (20). Accordingly, the battery housing (20) cannot be completely sealed, and the possibility of the electrolyte leaking to the outside when the electrolyte is injected becomes very high. That is, the structure of the conventional O-ring (100) is such that when a force is applied downward by the hopper (H), the bottom surface contacts the upper surface of the beading portion (21) of the battery housing (20), and then the side surface of the O-ring (100) is lifted to seal the side surface of the battery housing (20). According to this structure, the sealing effect is not sufficient because the O-ring (100) and the battery housing (20) maintain sealing through line contact.

[0074] Accordingly, the inventors of the present invention have developed an O-ring (100) structure for improving sealing performance by increasing the contact area between the battery housing (20) and the O-ring (100) compared to a conventional O-ring (100). In other words, the present invention relates to an O-ring (100) structure capable of preventing electrolyte leakage during electrolyte injection into a cylindrical battery cell. This will be described in detail with reference to FIGS. 7 to 10 below.

[0075]

[0076] Fig. 7 is a drawing for explaining an O-ring (100) according to one embodiment of the present invention. Fig. 8 is a drawing for explaining a state of the O-ring (100) of Fig. 7 before it is compressed, and Fig. 9 is an enlarged view of a portion of Fig. 8. Fig. 10 is a drawing for explaining a state of the O-ring (100) of Fig. 7 after it is compressed.

[0077] Referring to Fig. 7, the O-ring (100) includes a first part (110) and a second part (120). The O-ring (100) may further include a pressure surface (130). More specifically, the O-ring (100) may include a first part (110) that is seated on a beading portion (21) into which a battery housing (20) is inserted; and a second part (120) that is provided above the first part (110) and is configured to cover the upper surface (25) of the battery housing (20). The first part (110) and the second part (120) may be formed integrally. The O-ring (100) may be applied to a state before a crimping process is performed after the beading portion (21) is formed on the battery cell. That is, the O-ring (100) can be used in a state where the upper portion is not closed by the housing cover after the beading portion (21) is formed on the battery cell. That is, the O-ring (100) can be applied in a state where the upper portion of the battery cell is open.

[0078] The first part (110) may be configured, for example, in an approximately cylindrical shape. That is, since the first part (110) is mounted on the beading portion (21) of the cylindrical battery cell, it is preferable that it have a shape approximately similar to that of the battery housing (20). Accordingly, it is preferable that the first part (110) have an approximately cylindrical shape.

[0079] According to this structure, surface contact between the O-ring (100) and the battery housing (20) is enabled, thereby increasing the contact area. That is, according to the above-described structure of the present invention, when the O-ring (100) is compressed in the total height direction, most of the area where the battery housing (20) and the O-ring (100) come into contact in the form of surface contact, so that leakage of the electrolyte to the outside of the battery housing (20) can be effectively prevented when the electrolyte is injected.

[0080]

[0081] Meanwhile, the second part (120) is provided on the upper part of the first part (110) and must be able to cover the upper surface (25) of the battery housing (20), and thus may be configured in a roughly cylindrical shape as well. More specifically, the second part (120) may have a shape that extends further in the horizontal direction from the first part (110). Accordingly, the second part (120) may be configured in a cylindrical shape with a larger radius than the first part (110). However, the shape of the second part (120) is not limited to a cylindrical shape, and if it has a shape that protrudes outward in the radial direction more than the first part (110) and can cover the upper surface (25) of the battery housing (20), it will be said to be included in the scope of the present invention.

[0082] Preferably, the outer surface of the first part (110) may be configured in a cylindrical shape having an approximately constant radius. At this time, the distance from the center of the first part (110) to the outer surface of the first part (110) is preferably smaller than or equal to the inner diameter of the battery housing (20). If the distance from the center of the first part (110) to the outer surface of the first part (110) is larger than the inner diameter of the battery housing (20), the first part (110) cannot be smoothly inserted into the inside of the battery housing (20).

[0083]

[0084] In one aspect of the present invention, the O-ring (100) may be configured to have elasticity. That is, the O-ring (100) may be configured to have its shape deformed by external pressure. For example, the O-ring (100) may include at least one of NBR, VMQ, FKM, and FPM.

[0085] According to this configuration, when the O-ring (100) is inserted into the battery housing (20) and compressed in one direction, the shape of the O-ring (100) can be deformed to seal the battery housing (20). For example, when the O-ring (100) is compressed in the vertical direction, the horizontal thickness of the O-ring (100) can increase. Accordingly, the horizontal gap existing between the O-ring (100) and the battery housing (20) can be filled by the deformation of the O-ring (100). According to the elastic characteristic of the O-ring (100), the sealing performance can be improved, so that leakage of the electrolyte can be effectively prevented. In addition, the internal pressure of the battery housing (20) can be maintained or smoothly controlled.

[0086]

[0087] In another aspect of the present invention, the O-ring (100) may include a liquid injection hole (H3) extending vertically through the center thereof. Through the liquid injection hole (H3), the electrolyte may be injected into the battery housing (20).

[0088] According to the structure described above, when the O-ring (100) is inserted into the battery housing (20) and compressed in the vertical direction, the inner surfaces of the O-ring (100) and the battery housing (20) are in surface contact, thereby improving the sealing performance. Accordingly, electrolyte leakage can be prevented when electrolyte is injected. In addition, since the sealing performance between the O-ring (100) and the battery housing (20) is secured, the internal pressure of the battery housing (20) can be stably controlled.

[0089]

[0090] In one aspect of the present invention, the O-ring (100) may have a groove (G) into which a hopper (H) capable of pressurizing the O-ring (100) may be fitted. That is, the O-ring (100) and the hopper (H) may be configured to be detachable.

[0091] Referring again to FIG. 7, a hopper (H) capable of pressurizing the O-ring (100) may be inserted into the interior of the O-ring (100). The hopper (H) may be configured to pressurize at least a portion of the O-ring (100). For example, referring to FIG. 7, the hopper (H) may be inserted into a groove (G) provided in the interior of the O-ring (100), and the hopper (H) may be configured to pressurize the pressurizing surface (130) of the O-ring (100). Accordingly, the O-ring (100) may be pressed in the winding axis direction of the electrode assembly (10). More specifically, the O-ring (100) may be pressed downward.

[0092] According to the structure as described above, the replacement of the O-ring (100) becomes easy. That is, the O-ring (100) may frequently be damaged on the surface that comes into contact with the battery housing (20) due to repeated compression. At this time, according to the structure of the present invention as described above, since the groove (G) is provided in at least a portion of the O-ring (100) to make the hopper (H) detachable, the replacement of only the O-ring (100) can be facilitated. Furthermore, when the groove (G) is provided inside the O-ring (100) to mount the hopper (H) inside the O-ring (100), since most of the internal space of the O-ring (100) is occupied by the hopper (H), the cost of materials required for manufacturing the O-ring (100) can be reduced.

[0093]

[0094] In another aspect of the present invention, the outer surface of the first part (110) may be configured to be spaced apart from the inner surface of the battery housing (20) by a predetermined distance.

[0095] For example, referring to FIG. 8, the outer surface of the first part (110) may be spaced apart from the inner surface of the battery housing (20) by a predetermined distance. More specifically, the outer surface of the first part (110) and the inner surface of the battery housing (20) may be spaced apart from each other by a predetermined distance in the radial direction. For example, when the outer diameter of the battery housing (20) is about 46 mm and the inner diameter is about 45 mm, the outer surface of the first part (110) may be configured to be spaced apart from the inner surface of the battery housing (20) by about 0.2 to 0.8 mm. If the distance (D1) between the outer surface of the first part (110) and the inner surface of the battery housing (20) is less than about 0.2 mm, the process of inserting the O-ring (100) into the battery housing (20) may not be smooth. In another aspect, if the distance (D1) between the outer surface of the first part (110) and the inner surface of the battery housing (20) is greater than about 0.8 mm, surface contact for sealing may not be achieved when the O-ring (100) is compressed. Therefore, it is preferable that the outer surface of the first part (110) be configured to be spaced apart from the inner surface of the battery housing (20) by about 0.2 to 0.8 mm, and more preferably by about 0.5 to 0.7 mm. For example, as an example, the outer surface of the first part (110) may be configured to be spaced apart from the inner surface of the battery housing (20) by about 0.6 mm. Meanwhile, the present invention is not limited to the above absolute values, and it will be said that a relative value converted in relation to the size of the battery housing (20) is included in the scope of the present invention.

[0096] According to the structure as described above, the O-ring (100) can be smoothly inserted into the battery housing (20). In addition, when the O-ring (100) is compressed in one direction after being inserted, the shape of the O-ring (100) is deformed so that it comes into contact with the inner surface of the battery housing (20), thereby effectively sealing the battery housing (20).

[0097]

[0098] In another aspect of the present invention, the lower surface of the second part (120) may be configured to be spaced apart from the upper surface (25) of the battery housing (20) by a predetermined distance.

[0099] For example, referring to FIG. 8, the lower surface of the second part (120) may be spaced apart from the upper surface (25) of the battery housing (20) by a predetermined distance. More specifically, the lower surface of the second part (120) and the upper surface (25) of the battery housing (20) may be spaced apart from each other by a predetermined distance in the radial direction. For example, when the outer diameter of the battery housing (20) is about 46 mm and the inner diameter is about 45 mm, the lower surface of the second part (120) may be configured to be spaced apart from the upper surface (25) of the battery housing (20) by about 0.2 to 0.8 mm. If the distance (D2) between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20) is less than about 0.2 mm, when contact between the upper surface (25) of the battery housing (20) and the lower surface of the second part (120) is repeated due to repeated compression of the O-ring (100), the lower surface of the second part (120) may be more likely to be damaged. In another aspect, if the distance (D2) between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20) is greater than about 0.8 mm, surface contact for sealing may not be achieved when the O-ring (100) is compressed. Therefore, it is preferable that the lower surface of the second part (120) be configured to be spaced apart from the upper surface (25) of the battery housing (20) by about 0.2 to 0.8 mm, and more preferably by about 0.5 to 0.7 mm. For example, as an example, the lower surface of the second part (120) may be configured to be spaced apart from the upper surface (25) of the battery housing (20) by about 0.6 mm. Meanwhile, the present invention is not limited to the absolute values ​​as described above, and it will be said that a relative value converted in relation to the size of the battery housing (20) is included in the scope of the present invention.

[0100] According to the structure as described above, when the O-ring (100) is compressed, the shape of the second part (120) is deformed and the O-ring (100) comes into contact with the upper surface (25) of the battery housing (20), so that the battery housing (20) can be additionally sealed.

[0101]

[0102] In another aspect of the present invention, the outer diameter of the second part (120) may match the outer diameter of the battery housing (20).

[0103] For example, referring to FIG. 9, the outer surface of the battery housing (20) and the outer surface of the second part (120) may be configured to have substantially similar diameters. With this configuration, since the outer diameters of the battery housing (20) and the O-ring (100) are similar, even if contact between the upper surface (25) of the battery housing (20) and the lower surface of the second part (120) is repeated, the end of the O-ring (100) is deformed, thereby reducing the possibility of damage to the lower surface of the second part (120).

[0104] For example, in a conventional O-ring (100), since the outer diameter of the second part (120) is larger than the outer diameter of the battery housing (20), if contact is repeated between the upper surface (25) of the battery housing (20) and the lower surface of the second part (120), there is a high possibility that the point where the second part (120) contacts the upper surface (25) of the battery housing (20) will be damaged by being dug inward, but according to the structure as described above of the present invention, since the outer diameters of the battery housing (20) and the O-ring (100) are similar, even if the point where the second part (120) contacts the upper surface (25) of the battery housing (20) is deformed upward, the phenomenon of being dug inward can be prevented.

[0105]

[0106] In one aspect of the present invention, the O-ring (100) may include a pressurizing surface (130) provided on at least a portion of the O-ring (100) and configured to be pressed downward by the hopper (H). For example, the O-ring (100) may include a pressurizing surface (130) provided on the inside or outside of the O-ring (100) and configured to be pressed downward by the hopper (H).

[0107] For example, referring to FIG. 7, the pressurizing surface (130) may be configured to pressurize the O-ring (100) downward. For example, among the surfaces forming the groove (G) provided inside the O-ring (100), the upward-facing surface may correspond to the pressurizing surface (130). That is, among the surfaces forming the groove (G) provided inside the O-ring (100), the upward-facing surface comes into contact with the lower surface of the hopper (H), so the surface that is pressed by the lower surface of the hopper (H) may correspond to the pressurizing surface (130) of the O-ring (100). Alternatively, the upper surface of the O-ring (100) illustrated in FIG. 7 may also correspond to the pressurizing surface (130). For example, the hopper (H) may be fitted into the groove (G) provided inside the O-ring (100), but may also be shaped to pressurize the upper surface of the O-ring (100). That is, in the O-ring (100) illustrated in the embodiment of Fig. 7, the upward-facing surface among the surfaces forming the groove (G) provided inside the O-ring (100) and the upper surface of the O-ring (100) may correspond to the pressurizing surface (130).

[0108] In another aspect of the present invention, when the pressurizing surface (130) is pressed downward, the first part (110) may be configured to be compressed in the vertical direction and increase in width in the radial direction. That is, when pressure is applied from the outside of the battery housing (20) toward the beading portion (21) of the battery housing (20), the first part (110) may be configured to come into contact with the inner surface of the battery housing (20).

[0109] At this time, in order to reliably prevent leakage, it is preferable that the contact pressure between the outer surface of the first part (110) and the inner surface of the battery housing (20) be greater than the electrolyte injection pressure. For example, when the electrolyte injection pressure is about 8 bar, the contact pressure between the outer surface of the first part (110) and the inner surface of the battery housing (20) must be greater than about 8 bar to maintain sealing.

[0110]

[0111] In another aspect of the present invention, when the pressurizing surface (130) is pressed downward, the second part (120) may be configured to move downward and come into contact with the upper surface (25) of the battery housing (20). That is, when pressure is applied from the outside of the battery housing (20) toward the beading portion (21) of the battery housing (20), the second part (120) may be configured to come into contact with the upper surface (25) of the battery housing (20).

[0112] According to the above configuration, primary sealing is possible by sealing between the outer surface of the first part (110) and the inner surface of the battery housing (20), and secondary sealing is possible between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20).

[0113] At this time, in order to reliably prevent leakage, it is preferable that the contact pressure between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20) be greater than the electrolyte injection pressure. For example, when the electrolyte injection pressure is about 8 bar, a secondary sealing effect can be achieved if the contact pressure between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20) is greater than about 8 bar.

[0114] That is, according to the above configuration, when pressure is applied from the outside of the battery housing (20) toward the beading portion (21) of the battery housing (20), the O-ring (100) can be configured to block the outside and inside of the battery housing (20). Accordingly, the sealing performance of the battery housing (20) can be improved, and leakage of the electrolyte can be effectively prevented. In addition, the internal pressure of the battery housing (20) can be maintained or smoothly controlled.

[0115]

[0116] FIG. 11 is a drawing for explaining an O-ring (100) according to another embodiment of the present invention.

[0117] Since the O-ring (100) according to the present embodiment is similar to the O-ring (100) of the previous embodiment, duplicate descriptions of components that are substantially the same or similar to those of the previous embodiment will be omitted, and the following description will focus on differences from the previous embodiment.

[0118] Referring to Fig. 11, the second part (120) of the O-ring (100) may further include an extension cover portion (121). The extension cover portion (121) may extend downward from the second part (120) and may be configured to cover the outer surface of the upper surface (25) of the battery housing (20). The extension cover portion (121) may be configured to contact the outer surface of the battery housing (20). An end surface of the extension cover portion (121) may be configured to be parallel to the horizontal direction.

[0119] According to the above configuration, in addition to the primary sealing by sealing between the outer surface of the first part (110) and the inner surface of the battery housing (20), and the secondary sealing between the lower surface of the second part (120) and the upper surface (25) of the battery housing (20), a tertiary sealing between the inner surface of the extended cover part (121) and the outer surface of the battery housing (20) is possible. That is, sealing force can be additionally secured. At this time, it is preferable that the contact pressure between the inner surface of the extended cover part (121) and the outer surface of the battery housing (20) is greater than the injection pressure of the electrolyte.

[0120]

[0121] Fig. 12 is a drawing for explaining an O-ring (100) according to another embodiment of the present invention.

[0122] Since the O-ring (100) according to the present embodiment is similar to the O-ring (100) of the previous embodiment, duplicate descriptions of components that are substantially the same or similar to those of the previous embodiment will be omitted, and the following description will focus on differences from the previous embodiment.

[0123] Referring to FIG. 12, the O-ring (100) may include a lower surface (111). At this time, the lower surface (111) may be the lower surface (111) of the first part (110). That is, a lower surface among the surfaces constituting the first part (110) may correspond to the lower surface (111) of the O-ring (100). Referring again to FIG. 7, the lower surface (111) of the O-ring (100) is configured to contact the beading portion (21) and / or the current collector (30). More specifically, the lower surface (111) of the O-ring (100) may be configured to contact the upper surface of the beading portion (21) and / or the contact portion (33a) of the housing coupling portion (33) of the current collector (30). That is, the structure is such that the contact portion (33a) of the current collector (30) is seated on the upper surface of the beading portion (21). At this time, since the current collector (30) has a predetermined thickness, when the O-ring (100) is seated on the beading portion (21) and / or the current collector (30), a slight gap may exist between the O-ring (100) and the upper surface of the beading portion (21). At this time, the size of the slight gap may be the same as the thickness of the current collector (30). That is, a slight gap may exist between the O-ring (100) and the beading portion (21), and there is a possibility that the electrolyte may leak through this gap. Meanwhile, since the O-ring (100) has elasticity, when the O-ring (100) is pressed in the vertical direction, the size of the gap may be reduced. However, since there is a possibility that the gap may not be completely eliminated, it is preferable that the lower surface of the O-ring (100) be provided with at least one lower groove (113) so as to be aligned with the shape of the contact portion (33a) of the current collector (30).

[0124] More specifically, referring to FIG. 12, the thickness of the first part (110) may alternately increase and decrease along the circumferential direction. For example, the lower surface of the first part (110) may be provided with grooves (G) at predetermined intervals along the circumferential direction. Preferably, the grooves (G) may be configured to match the shape of the current collector (30). That is, the lower surface of the first part (110) is provided with at least one lower groove (113) dug upward. For example, in one embodiment, when the current collector (30) has four contact portions (33a), the lower surface of the O-ring (100) may also have four lower grooves (113). In this case, it is preferable that the shape of the contact portion (33a) and the shape of the lower groove (113) of the O-ring (100) match each other. For example, the contact portion (33a) of the current collector (30) may have an arc shape that extends at least partially in the circumferential direction along the beading portion (21) of the battery housing (20). Accordingly, the circumferential extension length of the contact portion (33a) may be formed longer than the width of the connecting portion (33b). As another embodiment, the contact portion (33a) may have an arc shape that extends in opposite directions along the circumferential direction on the beading portion (21) from the intersection of the connecting portion (33b) and the contact portion (33a). However, the number or shape of the contact portions (33a) of the current collector (30) or the number or shape of the lower grooves (113) of the O-ring (100) are not limited to this embodiment. That is, if the shape of the contact portion (33a) and the shape of the lower groove (113) of the O-ring (100) are matched with each other, it can be said to be included in the scope of the present invention.

[0125] According to the above configuration, the formation of a gap between the O-ring (100) and the beading portion (21) can be prevented. In other words, the O-ring (100) can more effectively seal the battery housing (20). Accordingly, the possibility of electrolyte leakage can be further reduced. In addition, an environment can be created in which the internal pressure of the battery housing (20) can be maintained at a constant level.

[0126]

[0127] FIG. 13 is a drawing for explaining an O-ring (100) according to another embodiment of the present invention.

[0128] Since the O-ring (100) according to the present embodiment is similar to the O-ring (100) of the previous embodiment, duplicate descriptions of components that are substantially the same or similar to those of the previous embodiment will be omitted, and the following description will focus on differences from the previous embodiment.

[0129] Referring to Fig. 13, the O-ring (100) does not include a groove (G) on the inside. The O-ring (100) may include a groove (G) on the outside. For example, only a liquid injection hole (H3) for injection is provided in the center of the O-ring (100) illustrated in Fig. 13, and a groove (G) for inserting a hopper (H) is not provided. Instead, a groove (G) for inserting a hopper (H) may be provided on the outer surface of the O-ring (100). In this way, the groove (G) may be provided on the outside or inside of the O-ring (100), and depending on the shape of the groove (G), the hopper (H) may also be coupled to the outside or inside of the O-ring (100). That is, the position where the groove (G) is provided is not limited, and if a hopper (H) can be mounted on the groove (G), and the hopper (H) is of a form that can compress the O-ring (100), it can be said to be included in the scope of the present invention.

[0130]

[0131] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

Claims

1. A first part in which the battery housing is mounted on the beaded portion inserted inward; and An O-ring comprising a second part provided above the first part and configured to cover the upper surface of the battery housing.

2. In paragraph 1, An O-ring characterized in that the first part is configured in a cylindrical shape.

3. In paragraph 1, An O-ring characterized in that the above O-ring has elasticity.

4. In paragraph 1, The above O-ring An O-ring characterized by comprising at least one of NBR, VMQ, FKM and FPM.

5. In paragraph 1, The above O-ring is characterized in that it includes a liquid hole extending vertically through the center.

6. In paragraph 1, The above O-ring, An O-ring characterized in that it has a groove into which a hopper capable of pressurizing the O-ring can be fitted.

7. In paragraph 1, An O-ring characterized in that the outer surface of the first part is configured to be spaced apart from the inner surface of the battery housing by a predetermined distance.

8. In paragraph 1, An O-ring characterized in that the outer surface of the first part is configured to be spaced apart from the inner surface of the battery housing by 0.2 to 0.8 mm.

9. In paragraph 1, An O-ring characterized in that the lower surface of the second part is configured to be spaced apart from the upper surface of the battery housing by a predetermined distance.

10. In paragraph 1, The above O-ring, An O-ring characterized by including a pressure surface provided on the inside or outside of the O-ring and configured to be pressurized downward by the hopper.

11. In paragraph 10, An O-ring characterized in that when the above-mentioned pressure surface is pressed downward, the first part is configured to increase in width in the radial direction while being compressed in the vertical direction.

12. In paragraph 10, An O-ring characterized in that when the pressure surface is pressed downward, the second part moves downward and is configured to come into contact with the upper surface of the battery housing.

13. In paragraph 1, An O-ring characterized in that when pressure is applied from the outside of the battery housing toward the beading portion of the battery housing, the O-ring is configured to block the outside and inside of the battery housing.

14. In paragraph 1, An O-ring characterized in that the thickness of the first part alternately increases and decreases along the circumferential direction.

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