Electrolyte Leak Prevention O-ring

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

1 / 26 Electrolyte Leak Prevention O-ring - Technical Field

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

[0002] This request is based on and claims priority from the Request of Korean Patent Number 10-2023-0096275, filed on July 24, 2023, with the Korean Intellectual Property Office, the description of which is incorporated herein in its entirety by reference.

[0003] This request is based on and claims priority from the Request of Korean Patent Number 10-2024-0092210, filed on July 12, 2024, with the Korean Intellectual Property Office, the description of which is incorporated herein in its entirety by reference. BACKGROUND OF THE TECHNIQUE

[0004] Secondary batteries that have high applicability according to product groups and electrical characteristics, such as high energy density, are commonly applied not only in portable devices, but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric energy sources. Such secondary batteries are attracting attention as a new energy source to improve sustainability and energy efficiency, because they have not only a primary advantage of drastically reducing the use of fossil fuels, but also of no byproducts generated by energy use.

[0005] Widely used secondary batteries today include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and the like. The operating voltage of a single secondary battery cell, namely a single battery cell, is approximately 2.5 V to 4.5 V. Therefore, if a higher output voltage is required, a plurality of battery cells can be connected in series. Petition 870250080820, dated 09 / 09 / 2025, page 7 / 53 2 / 26 to form a battery pack. Furthermore, depending on the required charging and discharging capacity of the battery pack, a plurality of battery cells can be connected in parallel to form a battery pack. Thus, the number of battery cells included in the battery pack can be variously defined according to the required output voltage and / or the demanded charging and discharging capacity.

[0006] Meanwhile, when manufacturing a cylindrical secondary battery, the electrode assembly is inserted into the battery housing, and then an electrolyte injection process is performed for activation. At this point, an O-ring is installed to prevent electrolyte from leaking out of the battery housing when the electrolyte is injected, and in the case of the conventional O-ring, there was the problem that the phenomenon of electrolyte leakage occurred due to a deterioration in leakage performance caused by contact with the battery housing. DESCRIPTION TECHNICAL PROBLEM

[0007] The present description is designed to solve the problems of the relevant art and, therefore, the present description is directed to providing an O-ring capable of preventing electrolyte from leaking to the outside of the battery housing when electrolyte is injected into a cylindrical battery cell.

[0008] More specifically, the present description is aimed at improving the sealing properties by expanding the contact area between the battery housing and the O-ring.

[0009] However, the technical problems to be solved by the present description are not limited to the problems described above, and other problems not mentioned here can be clearly understood by persons skilled in the art from the description following the present description. Petition 870250080820, dated 09 / 09 / 2025, page 8 / 53 3 / 26 TECHNICAL SOLUTION

[0010] An O-ring, according to an embodiment of the present description for solving the problem described above, includes a first part seated in a portion of a groove into which a battery housing is recessed; and a second part provided above the first part and configured to cover an upper end surface of the battery housing.

[0011] In one aspect of the present description, the first part can be configured in a cylindrical form.

[0012] In another aspect of the present description, the O-ring may have elasticity.

[0013] Preferably, the O-ring may include at least one NBR component, VMQ, FKM and FPM.

[0014] In yet another aspect of the present description, the O-ring may include an injection hole drilled in an upward and downward direction in the center.

[0015] In one aspect of the present description, the O-ring may have a groove into which a funnel capable of pressing the O-ring may be fitted.

[0016] In another aspect of the present description, the outer surface of the first part can be configured to be spaced from the inner surface of the battery housing by a predetermined distance.

[0017] Preferably, the outer surface of the first part can be configured to be spaced from the inner surface of the battery housing by 0.2 to 0.8 mm.

[0018] In yet another aspect of the present description, the lower surface of the second part can be configured to be spaced from the upper end surface of the battery housing by a predetermined distance. Petition 870250080820, dated 09 / 09 / 2025, page 9 / 53 4 / 26

[0019] In one aspect of the present description, the O-ring may include a pressing surface provided on the inside or outside of the O-ring and configured to be pressed down by the funnel.

[0020] Preferably, when the pressing surface is pressed down, the first part can be configured to increase in width in a radial direction as it is compressed in an up and down direction.

[0021] In another aspect of the present description, when the pressing surface is pressed down, the second part can be configured to move down and contact the upper end surface of the battery housing.

[0022] In yet another aspect of the present description, when pressure is applied from the outside of the battery housing towards the crimp portion of the battery housing, the O-ring can be configured to lock the outside and inside of the battery housing.

[0023] In yet another aspect of the present description, the thickness of the first part can repeatedly increase and decrease in an alternating manner along the circumferential direction. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0024] According to the present description, it is possible to prevent the electrolyte from leaking out of the battery housing when the electrolyte is injected into a cylindrical battery cell.

[0025] Furthermore, according to the present description, it is possible to expand the contact area between the battery housing and the O-ring.

[0026] Consequently, according to the present description, it is possible to improve the sealing performance of the battery cell when the electrolyte is injected.

[0027] However, the effects to be obtained by the present description are not limited to the effects described above, and other technical effects not mentioned herein may be clearly understood. Petition 870250080820, dated 09 / 09 / 2025, page 10 / 53 5 / 26 by persons skilled in the art of the following description of the present description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings illustrate a preferred embodiment of the present description and, together with the description above, serve to provide a better understanding of the technical characteristics of the present description and, therefore, the present description is not to be interpreted as being limited to the drawing.

[0029] Figure 1 is a view to describe a battery cell according to an embodiment of the present description.

[0030] Figure 2 is a cross-sectional perspective view of Figure 1.

[0031] Figure 3 is a cross-sectional view of the battery cell from Figure 1.

[0032] Figure 4 is a view to describe a conventional O-ring.

[0033] Figure 5 is a view to describe the state of a conventional O-ring before it is compressed.

[0034] Figure 6 is a view to describe the state of a conventional O-ring after being compressed.

[0035] Figure 7 is a view to describe an O-ring according to an embodiment of the present description.

[0036] Figure 8 is a view to describe a state of the O-ring of Figure 7 before being compressed.

[0037] Figure 9 is an enlarged view of a portion of Figure 8.

[0038] Figure 10 is a view to describe a state of the O-ring of Figure 7 after being compressed.

[0039] Figure 11 is a view to describe an O-ring according to another embodiment of the present description.

[0040] Figure 12 is a view to describe an O-ring according to yet another embodiment of the present description. Petition 870250080820, dated 09 / 09 / 2025, page 11 / 53 6 / 26

[0041] Figure 13 is a view to describe an O-ring according to yet another embodiment of the present description. BEST WAY TO IMPLEMENT THE INVENTION

[0042] Hereafter, preferred embodiments of the present description will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the accompanying claims should not be interpreted as limited to general and dictionary meanings, but interpreted based on the meanings and concepts that correspond to the technical aspects of the present description, based on the principle that the inventor is permitted to define the terms appropriately for the best explanation. Therefore, the description proposed here is only a preferred example for illustrative purposes only, not intending to limit the scope of the description; thus, it should be understood that other equivalents and modifications may be made to this without departing from the scope of the description.

[0043] In addition, to aid understanding of the present description, the attached drawings have not been drawn to scale, but the dimensions of some components may be exaggerated. Furthermore, the same reference numbers may be assigned to the same component in different embodiments.

[0044] A statement that two comparison objects are identical means 'substantially identical'. Therefore, 'substantially identical' may include deviations considered to be small in the technique, for example, deviations within 5%. Furthermore, the uniformity of a certain parameter in a predetermined region may mean that it is uniform in terms of a mean.

[0045] Although the terms first, second, and similar are used to describe various components, these components are not limited by these terms, of course. These terms are used only Petition 870250080820, dated 09 / 09 / 2025, page 12 / 53 7 / 26 to distinguish one component from another component and, unless otherwise indicated, it is obvious that the first component can be the second component.

[0046] As used herein, unless otherwise indicated, each component may be singular or plural.

[0047] Placing any component on top of (or below) a component or on the top (or bottom) of a component may mean not only that any component is arranged in contact with the top surface (or bottom surface) of the component, but also that other components may be interposed between the component and any component arranged above (or below) the component.

[0048] Furthermore, when it is described that a component is linked, coupled or connected to another component, the components may be directly linked or connected to each other, but it should be understood that yet another component may be interposed between each component, or each component may be linked, coupled or connected through yet another component.

[0049] As used herein, when referring to A and / or B, it means A, B, or A and B, unless expressly stated otherwise, and when referring to C to D, it means C or more and D or less, unless expressly stated otherwise.

[0050] Figure 1 is a view to describe a battery cell according to an embodiment of the present description, and Figure 2 is a cross-sectional perspective view of Figure 1. Figure 3 is a cross-sectional view of battery cell 1 of Figure 1.

[0051] Referring to Figure 1, a battery cell 1, according to one embodiment of the present description, includes an electrode assembly 10, a battery housing 20 and a current collector 30. The battery cell 1 may, in addition, also include a housing cover. Petition 870250080820, dated 09 / 09 / 2025, page 13 / 53 8 / 26 and / or a terminal 50 and / or a second current collector 60. The present description is not limited by the shape of the battery and may be applied to batteries of other shapes, such as prismatic batteries.

[0052] The electrode assembly 10 includes a first uncoated portion 11 and a second uncoated portion 12. More specifically, the electrode assembly 10 has a structure in which a first electrode, a second electrode, and a separator interposed between them are wound around a geometric winding axis to define a core and an outer circumferential surface. That is, the electrode assembly 10 applied to the present description can be a jelly-roll type electrode assembly 10. The electrode assembly 10 can be wound around the central winding hole H1. In this case, an additional separator can be provided on the outer circumferential surface of the electrode assembly 10 for insulation from the battery housing 20. The electrode assembly 10 can have a winding structure well known in the art, without limitations.Meanwhile, in the present description, the active material of the positive electrode coated on the positive electrode plate and the active material of the negative electrode coated on the negative electrode plate may be used without limitation, provided that they are active materials known in the art.

[0053] Referring to Figure 1, the battery housing 20 is an approximately cylindrical receiving container with an opening formed on one side and is made of a conductive metallic material. The lateral surface of the battery housing 20 and the lower surface located on the opposite side of the opening are generally integrally formed. That is, the battery housing 20 generally has an open upper end in the vertical direction and a closed lower end. The lower surface of the battery housing 20 may have an approximately flat shape. The lower surface of the battery housing 20 may constitute an external surface 20a of the closure. In this case, Petition 870250080820, dated 09 / 09 / 2025, page 14 / 53 9 / 26 the outer surface 20a of the closure can function as a second electrode terminal.

[0054] The battery housing 20 accommodates the electrode assembly through an opening formed on one side in the vertical direction. The battery housing 20 can also accommodate an electrolyte through the opening. The upper end surface 25 of the battery housing 20, which constitutes the opening, can be bent horizontally by a crimping process after the electrolyte is subsequently injected.

[0055] The battery housing 20 may include a crimp portion formed on an end portion adjacent to an opening provided at the upper end of the battery housing 20. The battery housing 20 may further include a crimp portion 22 formed on the crimp portion 21. The crimp portion 21 has a shape in which the circumference of the outer circumferential surface of the battery housing 20 is recessed to a predetermined depth. More specifically, the crimp portion 21 may have a shape in which it is recessed inwards in a region between an opening formed on one side of the battery housing 20 and a receiving portion that accommodates the electrode assembly 10.

[0056] The crimped portion 21 may provide a support surface on which at least a portion of the edge circumference of the current collector 30 to be described later may be seated and coupled. That is, at least a portion of the edge circumference of the current collector 30 of the present description and / or the edge circumference of the housing cover 40 may be seated on the upper surface of the crimped 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 crimped portion 21 may have a shape that Petition 870250080820, dated 09 / 09 / 2025, page 15 / 53 10 / 26 extends along a direction approximately parallel to the lower surface of the battery housing 20, that is, along a direction approximately perpendicular to the side wall of the battery housing 20.

[0057] Referring to Figures 1 to 3, the current collector 30, according to one embodiment of the present description, is housed within the battery housing 20, is electrically connected to the electrode assembly 10, and is also electrically connected to the 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 located on a surface of the electrode assembly 10, a tab coupling portion 32 extending from the support portion 31 and coupled to the first uncoated 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 for injecting an electrolyte in the center.

[0058] 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 description, the tab coupling portion 32 may have a greater width than the connection portion 33b. In another aspect of the present description, the contact portion 33a may have a greater width than the connection portion 33b.

[0059] The contact portion 33a is coupled to the inner surface of the battery housing 20. Preferably, the contact portion 33a can be coupled to the crimp portion 21 of the battery housing 20. In this case, for stable contact and coupling, both the crimp portion 21 and the contact portion 33a can have a shape that extends to Petition 870250080820, dated 09 / 09 / 2025, page 16 / 53 11 / 26 along a direction approximately parallel to the lower surface of the battery housing 20, that is, along a direction approximately perpendicular to the side wall of the battery housing 20.

[0060] Figure 4 is a view to describe a conventional O-ring 100. Figure 5 is a view to describe the state of a conventional O-ring 100 before being compressed, and Figure 6 is a view to describe the state of a conventional O-ring 100 after being compressed.

[0061] In general, the battery housing 20 of the cylindrical battery cell is subjected to an electrolyte injection process for activation after the insertion of the electrode assembly 10. At this time, an O-ring 100 is installed to prevent the electrolyte from leaking to the outside of the battery housing 20 when the electrolyte is injected and, in the case of the conventional O-ring 100, the phenomenon of electrolyte leakage occurred due to a deterioration in sealing performance, such as electrolyte leakage caused by contact with the battery housing 20.

[0062] For example, the conventional O-ring 100 is disposed in the contact portion 33a of the housing coupling portion 33 which is seated in the crimp portion 21. In this case, when the O-ring 100 is compressed in the direction of the battery cell height, i.e., in the direction of the geometric winding axis of the electrode assembly 10, the shape of the O-ring 100 is deformed by elasticity. For example, when the O-ring 100 is pressed downwards while seated in the crimp portion 21, as shown in Figure 5, the O-ring 100 is compressed in an upward and downward direction, as shown in Figure 6, and its shape is deformed. As a result, as shown in Figure 6, the area where the O-ring 100 is in contact with the current collector 30 and / or the battery housing 20 is reduced. That is, as the O-ring 100 is in Petition 870250080820, dated 09 / 09 / 2025, page 17 / 53 12 / 26 a line contact state with the current collector 30 and / or the battery housing 20 after being compressed, the battery housing 20 cannot be completely sealed. Consequently, a problem of electrolyte leakage to the outside when the electrolyte is injected is highly likely to occur.

[0063] More specifically, referring to Figures 4 to 6, in the conventional O-ring 100, the first part 110 has a shape in which a leg extends, instead of a cylindrical shape. In this case, when the O-ring 100 is pressed in an up and down direction, the leg portion of the first part 110 is lifted upwards, and the current collector 30 and / or the battery housing 20 and the first part 110 come into line contact. Consequently, the battery housing 20 cannot be completely sealed, and a problem of electrolyte leakage to the outside when the electrolyte is injected is highly likely to occur. That is, in the structure of the conventional O-ring 100, as a downward force is applied by the funnel H, the lower surface contacts the upper surface of the crimp 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 O-ring 100 and the battery housing 20 maintain the seal through line contact, so the sealing effect is not sufficient.

[0064] Therefore, the inventor of the present description has derived an O-ring 100 structure to improve sealing performance by expanding the contact area between the battery housing 20 and the O-ring 100 compared with the conventional O-ring 100. That is, the present description refers to an O-ring 100 structure capable of preventing electrolyte leakage when an electrolyte is injected into a cylindrical battery cell. This will be described in detail with reference to Figures 7 to 10 below. Petition 870250080820, dated 09 / 09 / 2025, page 18 / 53 13 / 26

[0065] Figure 7 is a view to describe an O-ring 100 according to an embodiment of the present description. Figure 8 is a view to describe a state of the O-ring 100 of Figure 7 before being compressed, and Figure 9 is an enlarged view of a portion of Figure 8. Figure 10 is a view to describe a state of the O-ring 100 of Figure 7 after being compressed.

[0066] Referring to Figure 7, the O-ring 100 includes a first part 110 and a second part 120. The O-ring 100 may further include a crimping surface 130. More specifically, the O-ring 100 may include a first part 110 seated on a crimp portion 21 into which a battery housing 20 is recessed; and a second part 120 provided above the first part 110 and configured to cover an upper end surface 25 of the battery housing 20. The first part 110 and the second part 120 may be integrally formed. The O-ring 100 may be applied to a state before a crimping process is performed after the crimp portion 21 is formed in the battery cell. That is, the O-ring 100 may be used in a state where the top is not closed by the housing cover, after the crimp portion 21 is formed in the battery cell. That is, the O-ring 100 can be applied in a state where the top of the battery cell is open.

[0067] The first part 110 can be configured, for example, in an approximately cylindrical shape. That is, as the first part 110 is seated on the flange portion 21 of the cylindrical battery cell, it is preferable to have a shape approximately similar to that of the battery housing 20. Therefore, it is preferable that the first part 110 have an approximately cylindrical shape.

[0068] According to this structure, surface contact between the O-ring 100 and the battery housing 20 is possible, so the contact area can be expanded. That is, according to the structure Petition 870250080820, dated 09 / 09 / 2025, page 19 / 53 14 / 26 of the present description, as described above, when the O-ring 100 is compressed in the full lift direction, most of the area where the battery housing 20 and the O-ring 100 contact can come into contact in the form of surface contact, thereby effectively preventing electrolyte from leaking out of the battery housing 20 when electrolyte is injected.

[0069] Meanwhile, the second part 120 is provided above the first part 110 and must be able to cover the upper surface 25 of the battery housing 20, so that it can be configured in an approximately cylindrical shape in the same way. More specifically, the second part 120 may have a shape that extends further in the horizontal direction than the first part 110. Therefore, 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 any shape that projects outward in the radial direction more than the first part 110 to cover the upper surface 25 of the battery housing 20 will be said to be included within the scope of the present description.

[0070] Preferably, the outer surface of the first part 110 can be configured in a cylindrical shape having an approximately constant radius. In this case, it is preferable that the distance from the center of the first part 110 to the outer surface of the first part 110 be less 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 greater than the inner diameter of the battery housing 20, the first part 110 cannot be smoothly inserted into the inner side of the battery housing 20.

[0071] In one aspect of the present description, the O-ring 100 can be configured to have elasticity. That is, the O-ring 100 can be configured so that its shape is deformed by external pressure. Petition 870250080820, dated 09 / 09 / 2025, page 20 / 53 15 / 26 For example, O-ring 100 may include at least one NBR, VMQ, FKM, and FPM component.

[0072] According to this configuration, when the O-ring 100 is inserted into the battery housing 20 and then 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 an up-and-down direction, the thickness of the O-ring 100 in the horizontal direction can increase. Consequently, the gap in the horizontal direction existing between the O-ring 100 and the battery housing 20 can be filled by the deformation of the O-ring 100. In this way, according to the elastic properties of the O-ring 100, the sealing performance can be improved, thereby effectively preventing electrolyte leakage. Furthermore, the internal pressure of the battery housing 20 can be maintained or controlled smoothly.

[0073] In another aspect of the present description, the O-ring 100 may include an injection hole H3 drilled in an upward and downward direction in the center. Through the injection hole H3, the electrolyte may be injected into the battery housing 20.

[0074] According to the structure above, when the O-ring 100 is inserted into the battery housing 20 and then compressed in an upward and downward direction, the O-ring 100 and the inner surface of the battery housing 20 come into surface contact with each other, thereby improving the sealing performance. Therefore, electrolyte leakage can be avoided when the electrolyte is injected. Furthermore, as the sealing performance between the O-ring 100 and the battery housing 20 is ensured, the internal pressure of the battery housing 20 can be stably controlled.

[0075] In one aspect of the present description, the O-ring 100 may have a groove G into which a funnel H capable of pressing the O-ring 100 Petition 870250080820, dated 09 / 09 / 2025, page 21 / 53 16 / 26 can be fitted. That is, the O-ring 100 and the funnel H can be configured to be detachable.

[0076] Referring to Figure 7 again, a funnel H capable of pressing the O-ring 100 can be inserted inside the O-ring 100. The funnel H can be configured to press at least a portion of the O-ring 100. For example, referring to Figure 7, the funnel H can be inserted into the groove G provided inside the O-ring 100, and the funnel H can be configured to press the pressing surface 130 of the O-ring 100. Consequently, the O-ring 100 can be pressed in the direction of the geometric winding axis of the electrode assembly 10. More specifically, the O-ring 100 can be pressed downwards.

[0077] According to the structure above, the replacement of the O-ring 100 is facilitated. That is, the O-ring 100 may be subject to frequent surface damage in contact with the battery housing 20 due to repeated compression. In this case, according to the structure of the present description, as described above, the groove G is provided in at least a portion of the O-ring 100 to make the funnel H detachable, so that only the O-ring 100 can be easily replaced. Furthermore, when the groove G is provided within the O-ring 100 to mount the funnel H inside the O-ring 100, the funnel H can occupy most of the internal space of the O-ring 100, thereby reducing the cost of materials required for the manufacture of the O-ring 100.

[0078] In another aspect of the present description, the outer surface of the first part 110 can be configured to be spaced from the inner surface of the battery housing 20 by a predetermined distance.

[0079] For example, referring to Figure 8, the outer surface of the first part 110 can be spaced from the inner surface of the battery housing 20 by a predetermined distance. More specifically Petition 870250080820, dated 09 / 09 / 2025, page 22 / 53 17 / 26 Typically, the outer surface of the first part 110 and the inner surface of the battery housing 20 can be spaced from each other by a predetermined distance in the radial direction. For example, when the outer diameter of the battery housing 20 is approximately 46 mm and the inner diameter is approximately 45 mm, the outer surface of the first part 110 can be configured to be spaced from the inner surface of the battery housing 20 by approximately 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 approximately 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 approximately 0.8 mm, surface contact for sealing may not be made when the O-ring 100 is compressed. Therefore, the outer surface of the first part 110 is preferably configured to be spaced from the inner surface of the battery housing 20 by approximately 0.2 to 0.8 mm, and more preferably by approximately 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 from the inner surface of the battery housing 20 by approximately 0.6 mm. On the other hand, the present description is not limited to the absolute values ​​above, and it should be said that relative values, converted relative to the size of the battery housing 20, are included in the scope of the present description.

[0080] According to the structure above, the O-ring 100 can be smoothly inserted into the battery housing 20. Furthermore, when the O-ring 100 is compressed in one direction after being inserted, the shape of the O-ring 100 can be deformed to contact the inner surface of the Petition 870250080820, dated 09 / 09 / 2025, page 23 / 53 18 / 26 battery housing 20, thereby effectively sealing battery housing 20.

[0081] In yet another aspect of the present description, the lower surface of the second part 120 can be configured to be spaced from the upper end surface 25 of the battery housing 20 by a predetermined distance.

[0082] For example, referring to Figure 8, the lower surface of the second part 120 can be spaced from the upper end surface 25 of the battery housing 20 by a predetermined distance. More specifically, the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 can be spaced from each other by a predetermined distance in the radial direction. For example, when the outer diameter of the battery housing 20 is approximately 46 mm and the inner diameter is approximately 45 mm, the lower surface of the second part 120 can be configured to be spaced from the upper end surface 25 of the battery housing 20 by approximately 0.2 to 0.8 mm.If the distance D2 between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 is less than approximately 0.2 mm, the possibility of damage to the lower surface of the second part 120 may increase when contact between the upper end 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. Conversely, if the distance D2 between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 is greater than approximately 0.8 mm, surface contact for sealing may not be made when the O-ring 100 is compressed. Therefore, the lower surface of the second part 120 is preferably configured to be spaced from the upper end surface 25 of the housing. Petition 870250080820, dated 09 / 09 / 2025, page 24 / 53 19 / 26 of battery 20 by approximately 0.2 to 0.8 mm, and more preferably by approximately 0.5 to 0.7 mm. For example, as an example, the lower surface of the second part 120 can be configured to be spaced from the upper end surface 25 of the battery housing 20 by approximately 0.6 mm. On the other hand, the present description is not limited to the absolute values ​​above, and it should be said that relative values, converted relative to the size of the battery housing 20, are included in the scope of the present description.

[0083] According to the structure above, when the O-ring 100 is compressed, the shape of the O-ring 100 can be deformed to allow the second part 120 to contact the upper end surface 25 of the battery housing 20, thereby further sealing the battery housing 20.

[0084] In yet another aspect of the present description, the outer diameter of the second part 120 may be the same as the outer diameter of the battery housing 20.

[0085] For example, referring to Figure 9, the outer surface of the battery housing 20 and the outer surface of the second part 120 can be configured to have substantially similar diameters. According to this configuration, the outer diameters of the battery housing 20 and the O-ring 100 are similar and, therefore, even if the contact between the upper end surface 25 of the battery housing 20 and the lower surface of the second part 120 is repeated, the possibility of damage to the lower surface of the second part 120 can be reduced by the deformation of the end of the O-ring 100.

[0086] For example, in the conventional O-ring 100, since the outer diameter of the second part 120 is larger than the outer diameter of the battery housing 20, it is highly likely that the point where the second part 120 contacts the upper end surface 25 of the battery housing 20 will be damaged by being dug inward if Petition 870250080820, dated 09 / 09 / 2025, page 25 / 53 20 / 26 the contact between the upper end surface 25 of the battery housing 20 and the lower surface of the second part 120 is repeated, but according to the structure of the present description, as described above, since the outer diameters of the battery housing 20 and the O-ring 100 are similar, the phenomenon of being hollowed inwards can be avoided even if the point where the second part 120 contacts the upper end surface 25 of the battery housing 20 is deformed upwards.

[0087] In one aspect of the present description, the O-ring 100 may include a pressing surface 130 provided in at least one portion of the O-ring 100 and configured to be pressed down by the funnel H. For example, the O-ring 100 may include a pressing surface 130 provided on the inside or outside of the O-ring 100 and configured to be pressed down by the funnel H.

[0088] For example, referring to Figure 7, the pressing surface 130 can be configured to press the O-ring 100 downwards. For example, between the surfaces forming the groove G provided within the O-ring 100, an upward-facing surface can correspond to the pressing surface 130. That is, between the surfaces forming the groove G provided within the O-ring 100, the upward-facing surface is in contact with the lower surface of the funnel H, and thus the surface pressed by the lower surface of the funnel H can correspond to the pressing surface 130 of the O-ring 100. Alternatively, the upper surface of the O-ring 100 shown in Figure 7 can also correspond to the pressing surface 130. For example, the funnel H can be fitted into the groove G provided within the O-ring 100, but the upper surface of the O-ring 100 can also be formed to press together.That is, in the O-ring 100 shown in the embodiment of Figure 7, the surface facing upwards between the surfaces that form the groove G provided within the O-ring 100 and a. Petition 870250080820, dated 09 / 09 / 2025, page 26 / 53 21 / 26 top surface of O-ring 100 can correspond to pressing surface 130.

[0089] In another aspect of the present description, when the pressing surface 130 is pressed down, the first part 110 can be configured to increase in width in a radial direction as it is compressed in an upward and downward direction. That is, when pressure is applied from the outside of the battery housing 20 towards the crimp portion 21 of the battery housing 20, the first part 110 can be configured to contact the inner surface of the battery housing 20.

[0090] In this case, 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, so as to reliably prevent leaks. For example, when the electrolyte injection pressure is approximately 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 approximately 8 bar to maintain the seal.

[0091] In yet another aspect of the present description, when the pressing surface 130 is pressed down, the second part 120 can be configured to move down and contact the upper end surface 25 of the battery housing 20. That is, when pressure is applied from the outside of the battery housing 20 towards the crimp portion 21 of the battery housing 20, the second part 120 can be configured to contact the upper end surface 25 of the battery housing 20.

[0092] According to the configuration above, a primary seal is formed by the seal between the outer surface of the first part 110 and the inner surface of the battery housing 20, and a secondary seal is formed by the seal between the outer surface of the first part 110 and the inner surface of the battery housing 20, and a secondary seal Petition 870250080820, dated 09 / 09 / 2025, page 27 / 53 22 / 26 between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 are possible.

[0093] In this case, it is preferable that the contact pressure between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 be greater than the electrolyte injection pressure in order to reliably prevent leaks. For example, when the electrolyte injection pressure is approximately 8 bar, the secondary sealing effect can be achieved if the contact pressure between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20 is greater than approximately 8 bar.

[0094] That is, according to the configuration above, when pressure is applied from the outside of the battery housing 20 towards the crimp portion 21 of the battery housing 20, the O-ring 100 can be configured to lock the outside and inside of the battery housing 20. Consequently, the sealing performance of the battery housing 20 can be improved and electrolyte leakage can be effectively prevented. In addition, the internal pressure of the battery housing 20 can be maintained or controlled smoothly.

[0095] Figure 11 is a view to describe an O-ring 100 according to another embodiment of the present description.

[0096] Since the O-ring 100 according to this embodiment is similar to the O-ring 100 of the previous embodiment, redundant descriptions of configurations that are substantially the same or similar to the previous embodiment will be omitted, and the following description will focus on the differences from the previous embodiment.

[0097] Referring to Figure 11, the second part 120 of the O-ring 100 may further include an extended cover portion 121. The extended cover portion 121 may extend downwards from the second part 120 and may be configured to cover the outer surface of the surface Petition 870250080820, dated 09 / 09 / 2025, page 28 / 53 23 / 26 of the upper end 25 of the battery housing 20. The extended cover portion 121 can be configured to contact the outer surface of the battery housing 20. The end surface of the extended cover portion 121 can be configured to be parallel to the horizontal direction.

[0098] According to the configuration above, in addition to the primary seal by the seal between the outer surface of the first part 110 and the inner surface of the battery housing 20 and the secondary seal between the lower surface of the second part 120 and the upper end surface 25 of the battery housing 20, a tertiary seal between the inner surface of the extended cover portion 121 and the outer surface of the battery housing 20 is possible. That is, the sealing force can be further ensured. In this case, it is preferable that the contact pressure between the inner surface of the extended cover portion 121 and the outer surface of the battery housing 20 be greater than the electrolyte injection pressure.

[0099] Figure 12 is a view to describe an O-ring 100 according to yet another embodiment of the present description.

[0100] Since the O-ring 100 according to this embodiment is similar to the O-ring 100 of the previous embodiment, redundant descriptions of configurations that are substantially the same or similar to the previous embodiment will be omitted, and the following description will focus on the differences from the previous embodiment.

[0101] Referring to Figure 12, the O-ring 100 may include a lower surface 111. In this case, the lower surface 111 may be the lower surface 111 of the first part 110. That is, a surface located in the lower portion between the surfaces that constitute the first part 110 may correspond to the lower surface 111 of the O-ring 100. Here, referring to Figure 7 again, the lower surface 111 of the O-ring 100 Petition 870250080820, dated 09 / 09 / 2025, p. 29 / 53 24 / 26 is configured to contact the crimp portion 21 and / or the current collector 30. More specifically, the lower surface 111 of the O-ring 100 can be configured to contact the upper surface of the crimp portion 21 and / or the contact portion 33a of the housing coupling portion 33 of the current collector 30. That is, there is a structure in which the contact portion 33a of the current collector 30 is seated on the upper surface of the crimp portion 21 and, in this case, the current collector 30 has a predetermined thickness, so that when the O-ring 100 is seated on the crimp portion 21 and / or the current collector 30, a minute gap can exist between the O-ring 100 and the upper surface of the crimp portion 21. In this case, the size of the minute gap can be the same as the thickness of the current collector 30.That is, a minute gap may exist between the O-ring 100 and the crimp portion 21, and there is a possibility that electrolyte may leak through this gap. Furthermore, the O-ring 100 has elasticity, and thus, when the O-ring 100 is pressed in an up and down direction, the size of the gap can 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 correspond to the shape of the contact portion 33a of the current collector 30.

[0102] More specifically, referring to Figure 12, the thickness of the first part 110 can repeatedly increase and decrease in an alternating manner along the circumferential direction. For example, the lower surface of the first part 110 can be provided with a groove G at a predetermined interval along the circumferential direction. Preferably, the groove G can be configured to correspond to the shape of the current collector 30. That is, the lower surface of the first part 110 is provided with at least one recessed lower groove 113. Petition 870250080820, dated 09 / 09 / 2025, page 30 / 53 25 / 26 upwards. For example, in one embodiment, when the contact portion 33a of the current collector 30 is provided with four, the lower groove 113 provided on the lower surface of the O-ring 100 may also be provided with four. 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 correspond to each other. For example, the contact portion 33a of the current collector 30 may have an arc shape in which at least a portion thereof extends in the circumferential direction along the crimp portion 21 of the battery housing 20. Consequently, the extension length of the contact portion 33a in the circumferential direction may be longer than the width of the connection portion 33b. As another embodiment, the contact portion 33a may have an arc shape that extends in opposite directions along the circumferential direction in the frieze portion 21 from the intersection point of the connection portion 33b and the contact portion 33a.However, the number or shape of the contact portion 33a of the current collector 30 or the number or shape of the lower groove 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 correspond to each other, it can be said to be included within the scope of the present description.

[0103] According to the configuration above, the formation of a gap between the O-ring 100 and the crimp portion 21 can be avoided. That is, the O-ring 100 can seal the battery housing 20 more effectively. Consequently, the possibility of electrolyte leakage can be further reduced. In addition, it is possible to create an environment in which the internal pressure of the battery housing 20 can be kept constant.

[0104] Figure 13 is a view to describe an O-ring 100 according to yet another embodiment of the present description.

[0105] Like the O-ring 100, according to this modality it is similar Petition 870250080820, dated 09 / 09 / 2025, p. 31 / 53 26 / 26 to O-ring 100 of the previous embodiment, redundant descriptions of configurations that are substantially the same or similar to the previous embodiment will be omitted, and the following description will focus on the differences from the previous embodiment.

[0106] Referring to Figure 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 the injection hole H3 for injection is provided in the center of the O-ring 100 shown in Figure 13, and a groove G for inserting a funnel H is not provided. Instead, a groove G for inserting a funnel H may be provided on the outer surface of the O-ring 100. Thus, a groove G may be provided on the outside or inside of the O-ring 100 and, depending on the shape of the groove G, a funnel 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, provided that a funnel H can be mounted in the groove G and the funnel H is in a shape capable of compressing the O-ring 100, it will be said to be included within the scope of the present description.

[0107] The present description has been described above with respect to a limited number of embodiments and designs, but the present description is not limited to this and various modifications and variations will be possible by persons skilled in the technical field pertaining to the present description, within the technical aspect of the present description and the scope of the appended claims and their equivalents. Petition 870250080820, dated 09 / 09 / 2025, p. 32 / 53

Claims

1 / 2 CLAIMS 1. O-ring, characterized in that it comprises: a first part seated in a groove portion into which a battery housing is recessed; and a second part provided above the first part and configured to cover an upper end surface of the battery housing.

2. O-ring, according to claim 1, characterized in that the first part is configured in a cylindrical shape.

3. O-ring, according to claim 1, characterized in that it has elasticity.

4. O-ring, according to claim 1, characterized in that it comprises at least one of NBR, VMQ, FKM and FPM.

5. O-ring, according to claim 1, characterized in that it comprises an injection hole drilled in an upward and downward direction in the center.

6. O-ring, according to claim 1, characterized in that it comprises a groove in which a funnel capable of pressing the O-ring can be fitted.

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

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

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

10. O-ring, according to claim 1, characterized in that it comprises a pressing surface provided on the inside or outside of the O-ring and configured to be pressed down by the funnel.

11. O-ring, according to claim 10, characterized in that, when the pressing surface is pressed down, the first part is configured to increase in width in a radial direction as it is compressed in an upward and downward direction.

12. O-ring, according to claim 10, characterized in that, when the pressing surface is pressed down, the second part is configured to move down and contact the upper end surface of the battery housing.

13. O-ring, according to claim 1, characterized in that, when pressure is applied from the outside of the battery housing towards the crimp portion of the battery housing, the O-ring is configured to lock the outside and inside of the battery housing.

14. O-ring, according to claim 1, characterized in that the thickness of the first part repeatedly increases and decreases in an alternating manner along the circumferential direction. Petition 870250080820, dated 09 / 09 / 2025, p. 34 / 53

Images