Battery cell, battery pack and vehicle

Abstract

Containing a battery cell: an electrode arrangement comprising a first electrode, a second electrode and a separator arranged between them; a battery housing configured to receive the electrode assembly through an opening formed on one side thereof; and a housing cover configured to cover the opening and featuring a vent section configured to rupture when the internal pressure of the battery housing rises to a predetermined level or higher, wherein the venting section has an upper notched section provided on the upper surface of the housing cover and a lower notched section provided on the lower surface of the housing cover, and wherein the upper notched section and the lower notched section are provided in an offset state.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a battery cell, a battery pack and a vehicle.

[0002] The present application claims priority over the Korean patent application with application number 10-2022-0157708, which was filed in the Republic of Korea on November 22, 2022, the disclosures of which are incorporated herein by reference. STATE OF THE ART

[0003] Secondary batteries, which are easy to use depending on the product group and exhibit electrical properties such as high energy density, are generally used in electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by an electric drive source, as well as in portable devices. These secondary batteries are attracting attention as a new energy source for improving environmental friendliness and energy efficiency, as they have the primary advantage of being able to dramatically reduce the use of fossil fuels, and no byproducts are generated due to energy consumption.

[0004] Commonly used secondary batteries currently include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and similar types. The operating voltage of a standard secondary battery cell is approximately 2.5 V to 4.5 V. Therefore, if a higher output voltage is required, a battery pack can be configured by connecting multiple cells in series. Additionally, a battery pack can be configured by connecting multiple cells in parallel, depending on the required charge / discharge capacity. Thus, the number of cells in a battery pack can be adjusted in various ways, depending on the required output voltage or charge / discharge capacity.

[0005] The battery cell can comprise a battery can and a cap that covers one side of the can. In this case, the cap can have a vent designed to prevent an increase in internal pressure caused by gases generated within the battery can. In a conventional battery cell, a high degree of deformation is accepted when creating notches to ensure a certain level of venting pressure, thereby increasing the risk of damage to the molding tools. Therefore, it is desirable to reduce damage to the molding tools during notch formation and to improve tool life. Additionally, there is a problem of decreased productivity due to the high degree of deformation during the notch formation process. RevelationTechnical Task

[0006] The present disclosure was developed to solve the problems of the prior art, and therefore the present disclosure is intended to efficiently ensure the venting pressure even with a low degree of deformation when forming a notch in a venting section of a battery cell.

[0007] Furthermore, the present disclosure is intended to reduce damage to forming tools when forming a notch in the venting section of the battery cell, thereby increasing and improving the service life of the battery cell.

[0008] According to another aspect, the present disclosure is intended to increase productivity by reducing the degree of deformation.

[0009] However, the technical problems that the present disclosure seeks to solve are not limited to the problems mentioned above, and other problems not mentioned above will be clearly understood by those skilled in the art from the description of the invention described below. Technical solution

[0010] According to one aspect of the present disclosure, a battery cell is provided comprising: an electrode assembly having a first electrode, a second electrode and a separator arranged between them; a battery case configured to receive the electrode assembly through an opening formed on one side thereof; and a case cover configured to cover the opening and having a vent section configured to rupture when the internal pressure of the battery case rises to a predetermined level or higher, wherein the vent section includes an upper notched section provided on the upper surface of the case cover and a lower notched section provided on the lower surface of the case cover, and wherein the upper notched section and the lower notched section are provided in an offset state.

[0011] Preferably, the venting section can be configured to form a circular closed ring.

[0012] In one aspect of the present disclosure, the centerline of the upper notched section and the centerline of the lower notched section can be spaced apart from each other in the radial direction by a predetermined distance.

[0013] Preferably, the upper notched section can be positioned further inwards in the radial direction than the lower notched section.

[0014] In another aspect of the present disclosure, the upper notched section and the lower notched section can be configured such that their widths decrease towards the inside of the housing cover, starting from its surface.

[0015] In another aspect of the present disclosure, the upper notched section may have an axisymmetric structure to exhibit an inclination relative to the centerline of the upper notched section, and the lower notched section may have an axisymmetric structure to exhibit an inclination relative to the centerline of the lower notched section.

[0016] In one aspect of the present disclosure, a first straight line SL, which is a fictitious straight line passing through the shortest distance between the upper notched section and the lower notched section, and a second straight line, which is a fictitious straight line perpendicular to the first straight line, can be defined in the longitudinal cross-section passing through the center of the housing cover.

[0017] In this case, the angle formed between the second straight line and the surface of the case cover can be greater than 0 degrees and less than 90 degrees.

[0018] In one aspect of the present disclosure, assuming that the width of the entrance of the upper notched section is W1 and that the width of the entrance of the lower notched section is W2, the distance between the centerline of the upper notched section and the centerline of the lower notched section can satisfy the following equation 1 0 <D2<W1+W22

[0019] In another aspect of the present disclosure, the upper notched section and the lower notched section can be configured to be point-symmetric to each other in the longitudinal cross-section passing through the center of the housing cover.

[0020] In another aspect of the present disclosure, in the longitudinal cross-section passing through the center of the housing cover, the shortest distance between the upper notched section and the lower notched section can be configured to be greater than the shortest distance between the upper notched section and the lower notched section in the case where the upper notched section and the lower notched section are provided at the same position in the radial direction.

[0021] In another aspect of the present disclosure, in the longitudinal cross-section passing through the center of the housing cover, the shortest distance between the upper notched section and the lower notched section may be smaller than the thickness of the housing cover.

[0022] In another aspect of the present disclosure, an area where the upper notched section is formed and an area where the lower notched section is formed can be configured to overlap each other at least partially in a direction perpendicular to the housing cover.

[0023] In another aspect of the present disclosure, the shortest distance between the upper notched section and the lower notched section can be greater than 10% of the thickness of the housing cover.

[0024] Fener provides a battery pack comprising at least one battery cell according to the embodiments described above.

[0025] In addition, the present disclosure provides a vehicle that has at least one battery pack according to the embodiment described above. Beneficial effects

[0026] According to the present disclosure, it is possible to ensure a predetermined level of venting pressure in the battery cell even with a low degree of deformation.

[0027] According to another aspect of the present disclosure, low deformation during notching makes it possible to reduce damage to forming tools, thereby increasing the service life of the battery cell.

[0028] According to another aspect of the present disclosure, it is possible to increase productivity by reducing the degree of deformation.

[0029] However, the effects obtainable from the present disclosure are not limited to the effects mentioned above, and further effects not expressly mentioned above will be clearly recognizable to the person skilled in the art from the following description of the invention. DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings illustrate a preferred embodiment of the present disclosure and, together with the detailed description of the invention, serve to provide a further understanding of the technical concept of the present disclosure, and thus the present disclosure is not to be construed as being limited to the drawings. Fig. Figure 1 is a diagram illustrating a battery cell according to one embodiment of the present disclosure. Fig. Figure 2 is a longitudinal and perspective view in Fig. 1. Fig. 3 is a longitudinal section view of the battery cell in Fig. 1. Fig. Figure 4 is a diagram illustrating a housing cover according to an embodiment of the present disclosure. Fig. Figure 5 is a drawing illustrating a housing cover according to a comparative example in the present disclosure. Fig. Figure 6 is a diagram illustrating a housing cover according to an embodiment of the present disclosure. Fig. Figure 7 is a diagram illustrating a housing cover according to another embodiment of the present disclosure. Fig. Figure 8 is a diagram illustrating a venting section according to an embodiment of the present disclosure. Fig. Figure 9 is a diagram illustrating the interruption process of the venting section according to a comparative example in the present disclosure. Fig. Figure 10 is a diagram illustrating the interruption process of the venting section according to an embodiment of the present disclosure. Fig. Figure 11 is a diagram illustrating a battery pack with a battery cell according to an embodiment of the present disclosure. Fig. 12 is a diagram showing a vehicle with the battery pack in Fig. 11 illustrated. EXECUTION FORMS

[0031] Preferred embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. Prior to the description, it should be understood that the terms used in the description and the accompanying claims should not be interpreted as being limited to general and dictionary-like meanings, but rather should be interpreted based on the meanings and concepts that correspond to the technical aspects of the present disclosure, on the basis of the principle that the inventor is permitted to define terms appropriately for the best possible explanation.Therefore, the configurations proposed in the embodiments and drawings of this description only indicate the most preferred embodiment of the present disclosure and do not represent all the technical ideas of the present disclosure, so it is understood that various equivalents and modifications could be made to it at the time of filing the application.

[0032] In addition, the accompanying drawings are not drawn to scale for better understanding of the present disclosure, and the dimensions of some elements may be exaggerated or understated. Furthermore, the same reference numerals may denote the same components in different embodiments.

[0033] Therefore, "essentially the same" can encompass a case that exhibits a deviation considered minor in engineering, for example, a deviation of less than 5%. Additionally, a parameter that is uniform within a specific range can indicate that it is uniform from an average perspective.

[0034] Although "first," "second," etc., are used to describe different components, these components are not limited to these terms. These terms are only used to distinguish one component from another, and unless otherwise specified, a first component can also be a second component.

[0035] Throughout the entire description, unless otherwise specified, an element can refer to a single element or multiple elements.

[0036] A configuration in which a component is located “in the upper section or lower section” or “on the top or bottom” of a target component can indicate that the component may be located in contact with the upper surface or lower surface of the target component and that another component may be located between the target component and the component located on the top or bottom of the target component.

[0037] Additionally, the expression “a component” is “connected”, “coupled” or “attached” to another component should be understood to mean that the components may be directly connected or attached to each other, and that another component may be “arranged” between the components, or that the components may be “connected”, “coupled” or “attached” by other components.

[0038] Throughout the description, unless otherwise specified, “A and / or B” may refer to A or B or A and B, and unless otherwise specified, “C to D” may refer to “equal to or greater than C and equal to or less than D”.

[0039] For the sake of simplicity, the longitudinal direction of a winding axis of an electrode arrangement 10 wound in a jellyroll shape is referred to in this description as the "axial direction (Y)". Additionally, the direction surrounding the winding axis is referred to as the "circumferential direction (X)". Furthermore, the direction approaching or moving away from the winding axis is referred to as the "radial direction". Within this, the direction approaching the winding axis is referred to as the "centripetal direction", and the direction moving away from the winding axis is referred to as the "centrifugal direction".

[0040] Fig. Figure 1 is a diagram illustrating a battery cell 1 according to an embodiment of the present disclosure, and Fig. Figure 2 is a longitudinal and perspective view in Fig. 1. Fig. Figure 3 is a longitudinal section view of battery cell 1 in Fig. 1.

[0041] With reference to Fig. According to one embodiment of the present disclosure, the battery cell 1 comprises an electrode arrangement 10, a battery housing 20, and a housing cover 30. The battery cell 1 may further comprise a collector 40. The present disclosure is not limited to a particular type of battery and can be applied to other types of batteries, such as a prismatic battery.

[0042] With reference to Fig. 2 and Fig. 3. The electrode arrangement 10 has a first electrode tab 11 and a second electrode tab 12. In particular, the electrode arrangement 10 has a first electrode, a second electrode, and a separator arranged between them. The electrode arrangement 10 has a structure in which a first electrode and a second electrode are wound around a winding axis, while a separator is arranged between them, defining a core and an outer circumferential surface. That is to say, the electrode arrangement 10 applied to the present disclosure can be a jellyroll-type electrode arrangement 10. In this case, an additional separator can be provided on the outer circumferential surface of the electrode arrangement 10 to insulate it from the battery housing 20. The electrode arrangement 10 can have a winding structure as conventionally known, without restrictions.

[0043] In the present disclosure, any active material that is conventionally known can be used without restriction as the active material of the positive electrode, which is applied to the positive electrode plate, and as the active material of the negative electrode, which is applied to the negative electrode plate.

[0044] With reference to Fig. 1 and Fig. 2. The battery housing 20 is an essentially cylindrical container with an opening formed on one side and is made of a conductive metal material. Generally, the side surface of the battery housing 20 and the bottom surface opposite the opening are integral. That is, the battery housing 20 is generally configured such that its top is open in the vertical direction and its bottom is closed. The bottom surface of the battery housing 20 can be configured in an essentially flat shape. The battery housing 20 accommodates the electrode assembly 10 through the opening formed on one side in the vertical direction. The battery housing 20 can also accommodate an electrolyte through the opening.

[0045] The battery housing 20 can have a beaded section 21 formed at one end adjacent to the opening provided on the top of the battery housing 20. The battery housing 20 can further have a crimped section 22 formed on the beaded section 21. The beaded section 21 can be configured such that the outer circumferential surface of the battery housing 20 is press-fitted to a predetermined depth. In particular, the beaded section 21 can be configured such that it is press-fitted inwards in the area between the opening formed on one side of the battery housing 20 and a receiving section that receives the electrode assembly 10.

[0046] The corrugated section 21 is formed above the electrode arrangement 10. The inner diameter of the battery housing 20 in the area where the corrugated section 21 is formed is smaller than the diameter of the electrode arrangement 10.

[0047] The corrugated section 21 provides a support surface on which the housing cover 40 sits. Additionally, the corrugated section 21 can provide a support surface on which at least one section of the edge of the collector 40 sits and is coupled. That is, at least one section of the edge of the collector 40 of this disclosure and / or the edge of the housing cover 30 can sit on the upper surface of the corrugated section 21. To stably support at least one section of the edge of the collector 40 and / or the edge of the housing cover 30, the upper surface of the corrugated section 21 can be configured to extend in a direction approximately parallel to the bottom surface of the battery housing 20, that is, in a direction approximately perpendicular to the side wall of the battery housing 20.

[0048] The corrugated section 21 can prevent the electrode assembly 10, which may have a size approximately equal to the inner diameter of the battery housing 20, from protruding through the opening formed on the top of the battery housing 20, and can serve as a support section on which the housing cover 30 sits. The upper corrugated section 21 can also function as a support section for attaching the collector 40, a seal G1, and the like, as well as the housing cover 30.

[0049] The crimp section 22 is formed on the upper surface of the bead section 21. The crimp section 22 is configured to extend and be bent in such a way as to surround the edge of the housing cover 30, which is positioned above the bead section 21. This configuration of the crimp section 22 allows the housing cover 30 to be attached to the bead section 21.

[0050] With reference to Fig. 1 to Fig. 3. The housing cover 30 can have a vent section 31 designed to prevent an increase in internal pressure due to gases generated in the battery housing 20. The vent section 31 can be configured to rupture when the internal pressure of the battery housing 20 rises to a predetermined level or higher. For example, the vent section 31 can be formed in a section of the housing cover 30 and can be a more vulnerable area in the structure than the surrounding area, making it more susceptible to rupture when internal pressure is applied. For example, the vent section 31 can be a region with a lesser thickness than the surrounding area.

[0051] Specifically, a thermal event – ​​for any reason – can occur in battery cell 1, generating vent gas, causing the pressure in the battery casing 20 to rise due to the vent gas. When vent gas is generated, the vent section 31 can rupture, as it is a structurally less robust area than the surrounding area and therefore more likely to rupture when the internal pressure of battery cell 1 increases.

[0052] With reference to Fig. 1 to Fig. 3. The housing cover 30 covers the opening formed on one side of the battery housing 20. The housing cover 30 can be secured by the crimp section 22 formed on the top of the battery housing 20. In this case, a gasket G1 can be arranged between the battery housing 20 and the housing cover 30, and between the collector 40 and the housing cover 30, to improve the fastening force and the airtightness of the battery housing 20. In this case, a contact section 33a and / or a second contact section can be arranged between the beaded section 21 of the battery housing 20 and the gasket G1. The contact section 33a and / or the second contact section arranged between the beaded section 21 and the gasket G1, as described above, can be secured by bending the crimp section 22, which extends upward from the beaded section 21.

[0053] In the present disclosure, the housing cover 30 is not a component that needs to function as a current path. Therefore, the seal G1 is not necessarily required, as long as the airtightness of the opening of the battery housing 20 can be ensured by firmly fastening the battery housing 20 and the housing cover 30 by welding or fastening using other parts.

[0054] Fig. Figure 4 is a diagram illustrating a housing cover 30 according to an embodiment of the present disclosure. Fig. Figure 5 is a drawing illustrating a housing cover 30 according to a comparative example in the present disclosure, and Fig. Figure 6 is a diagram illustrating a housing cover 30 according to an embodiment of the present disclosure.

[0055] With reference to Fig. 4 and Fig. 6. The vent section 31 can have an upper notched section N1, provided on the upper surface of the housing cover 30, and a lower notched section N2, provided on the lower surface of the housing cover 30. Here, the upper notched section N1 and the lower notched section N2 can be provided in an offset state.

[0056] According to this structure, since the upper notched section N1 and the lower notched section N2 are provided in the offset state, a shear stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2.

[0057] If the upper notched section N1 and the lower notched section N2 are provided on the same line in the conventional housing cover 30, which is in Fig. As shown in Figure 5, a tensile stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2. In the case where the area between the upper notched section N1 and the lower notched section N2 is subjected to the same magnitude of compression as shown in Figure 5, the tensile stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2. Fig. 5 or Fig. As shown in Figure 6, it is more likely to break under shear stress compared to tensile stress. Therefore, according to the present disclosure, the vent section 31 can break even if a lower venting pressure is applied to it. Alternatively, since the upper notched section N1 and the lower notched section N2 are in the offset state, it may be possible to ensure the same venting pressure with a lower degree of deformation. As a result, damage to mold tools can be reduced by decreasing the degree of deformation, which is expected to increase the service life of the housing cover 30.

[0058] With reference to Fig. 1 to Fig. 4. The vent section 31 can be configured to form an essentially circular closed ring. Accordingly, if venting gas is expelled from the interior of the battery cell 1, exerting an upward internal pressure on the housing cover 30, the vent section 31 can rupture, and the inner portion of the circular closed ring of the housing cover 30 can break open. Thus, venting can be easily carried out.

[0059] Fig. Figure 7 is a diagram illustrating a housing cover 30 according to another embodiment of the present disclosure.

[0060] In one aspect of the present disclosure, the centerline of the upper notched section N1 and the centerline of the lower notched section N2 can be configured to be spaced apart from each other in the radial direction by a predetermined distance. Here, the centerline can specify a line extending in the vertical direction of the battery cell 1 and passing through the lateral center of the notched section N1 or N2.

[0061] For example, with reference to Fig. 6 the upper notched section N1 is provided further inwards in the radial direction than the lower notched section N2. As another embodiment of the present disclosure, with reference to Fig. 7 the upper notched section N1 is provided further outwards in the radial direction than the lower notched section N2.

[0062] According to the structure, which is configured such that the centerline of the upper notched section N1 and the centerline of the lower notched section N2 are radially spaced apart by a predetermined distance, shear stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2. Therefore, according to the present disclosure, the vent section 31 can rupture even when a lower venting pressure is applied to it. Alternatively, since the upper notched section N1 and the lower notched section N2 are in the offset state, it may be possible to ensure the same venting pressure with a lower degree of deformation. As a result, damage to mold tools can be reduced by decreasing the degree of deformation, thereby increasing the service life of the housing cover 30.

[0063] In another aspect of the present disclosure, the upper notched section N1 and the lower notched section N2 can be configured such that their widths decrease towards the inside of the housing cover 30 from the surface thereof.

[0064] For example, with reference to Fig. 6 or Fig. 7. The upper notched section N1 and the lower notched section N2 may be configured to have a substantially V-shaped cross-section. Alternatively, in another embodiment, the upper notched section N1 and the lower notched section N2 may be configured to have a substantially U-shaped cross-section. That is, the cross-sections of the notched sections N1 and N2 may be configured to have slopes on both sides.

[0065] According to this structure, in the case where the centerline of the upper notched section N1 and the centerline of the lower notched section N2 are spaced apart in the radial direction by a predetermined distance, a shear stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2.

[0066] If, contrary to the present disclosure, the notched sections N1 and N2 have a rectangular cross-section, even if the centerline of the upper notched section N1 and the centerline of the lower notched section N2 are spaced apart radially by a predetermined distance, the area between the upper notched section N1 and the lower notched section N2 may have a vertical structure instead of an inclined one. Consequently, in this state, the shear stress cannot be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2. Thus, the venting pressure required for interruption may necessarily increase compared to the present disclosure.

[0067] On the other hand, according to the present disclosure, since the area between the upper notched section N1 and the lower notched section N2 has an inclined structure, in the case where the centerline of the upper notched section N1 and the centerline of the lower notched section N2 are spaced apart from each other in the radial direction by a predetermined distance, the stress exerted on the area between the upper notched section N1 and the lower notched section N2 can be the shear stress.

[0068] Preferably, with reference to Fig. 6 or Fig. 7. The upper notched section N1 may have an axially symmetric structure to exhibit a slope relative to the centerline of the upper notched section N1. Conversely, the lower notched section N2 may have an axially symmetric structure to exhibit a slope relative to the centerline of the lower notched section N2.

[0069] According to this structure, since the area between the upper notched section N1 and the lower notched section N2 has an inclined structure, shear stress can be the dominant stress exerted on the area between the upper notched section N1 and the lower notched section N2 if the centerline of the upper notched section N1 and the centerline of the lower notched section N2 are spaced apart radially by a predetermined distance. Additionally, since the notched sections N1 and N2 have an axially symmetric structure relative to the centerline, it can be easily formed during the manufacturing process.

[0070] Fig. Figure 8 is a diagram illustrating a venting section 31 according to an embodiment of the present disclosure.

[0071] With reference to Fig. 8 can be defined in the longitudinal cross-section passing through the center of the housing cover 30, a first straight line SL, which is an imaginary straight line passing through the shortest distance D1 between the upper notched section N1 and the lower notched section N2, and a second straight line PL, which is an imaginary straight line perpendicular to the first straight line SL.

[0072] In this case, according to one aspect of the present disclosure, the angle formed between the second straight line PL and the surface of the housing cover 30 can be greater than 0 degrees and less than 90 degrees.

[0073] For example, if the upper notched section N1 and the lower notched section N2 are provided on the same line, as in Fig. As shown in Figure 5, the first straight line SL can be perpendicular to the housing cover 30. Accordingly, since the second straight line PL is parallel to the housing cover 30, the angle formed between the second straight line PL and the surface of the housing cover 30 can be 0 degrees. According to this structure, the stress exerted on the area between the upper notched section N1 and the lower notched section N2 becomes tensile stress, thus increasing the venting pressure required to interrupt the venting section 31. Although the thickness of the area between the upper notched section N1 and the lower notched section N2 can be reduced by increasing the size of the notched sections to decrease the venting pressure, this requires a greater degree of deformation, increasing the risk of damage to the mold tools. This can reduce the service life of the housing cover 30.Against this background, it is preferred that the angle formed between the second straight line PL and the surface of the housing cover 30 is greater than 0 degrees.

[0074] On the other hand, if the distance D2 between the centerline of the upper notched section N1 and the centerline of the lower notched section N2 is too long, the first straight line SL may be almost parallel to the surface of the housing cover 30. This can cause the angle formed between the second straight line PL and the surface of the housing cover 30 to approach 90 degrees. In this case, the distance D2 between the upper notched section N1 and the lower notched section N2 increases excessively to increase the thickness of the area between the upper notched section N1 and the lower notched section N2, thus further increasing the venting pressure required to interrupt the vent section 31. Therefore, it is preferred that the angle formed between the second straight line PL and the surface of the housing cover 30 be less than 90 degrees.

[0075] Furthermore, it is preferred that the angle formed between the second straight line PL and the surface of the housing cover 30 lies in the range of 30 to 60 degrees. If the angle falls within this range, the thickness of the area between the upper notched section N1 and the lower notched section N2 can remain at a suitable level, while simultaneously exerting shear stress on the area between the upper notched section N1 and the lower notched section N2. Thus, according to the present embodiment, it may be possible to ensure the same venting pressure even with a low degree of deformation. As a result, damage to mold tools can be reduced by decreasing the degree of deformation, thereby increasing the service life of the housing cover 30.

[0076] In another aspect of the present revelation, with reference to Fig. 8, it is preferred that the distance D2 between the center line of the upper notched section N1 and the center line of the lower notched section N2 satisfies the following equation. 0 <D2<W1+W22

[0077] Here, W1 refers to the width of the entrance of the upper notched section N1, and W2 refers to the width of the entrance of the lower notched section N2. That is, it is preferred that the distance D2 between the centerline of the upper notched section N1 and the centerline of the lower notched section N2 is less than the average of the width W1 of the entrance of the upper notched section N1 and the width W2 of the entrance of the lower notched section N2, and greater than 0.

[0078] If the distance D2 between the centerline of the upper notched section N1 and the centerline of the lower notched section N2 is greater than the average of the width W1 of the inlet of the upper notched section N1 and the width W2 of the inlet of the lower notched section N2, the distance D2 between the upper notched section N1 and the lower notched section N2 can increase excessively, thereby increasing the thickness of the area between the upper notched section N1 and the lower notched section N2, thus further increasing the venting pressure required to interrupt the vent section 31. Conversely, if the distance D2 between the centerline of the upper notched section N1 and the centerline of the lower notched section N2 is 0, the upper notched section N1 and the lower notched section N2 can be positioned on the same line.Thus, the dominant force exerted on the vent section 31 can be the tensile stress. As a result, the venting pressure required to interrupt the vent section 31 can be further increased. Therefore, it may be possible to ensure the same venting pressure even with a low degree of deformation only if Equation 1 above is satisfied. As a result, damage to mold tools can be reduced by decreasing the degree of deformation, which is expected to increase the service life of the housing cover 30.

[0079] In another aspect of the present disclosure, the upper notched section N1 and the lower notched section N2 can be configured to be point-symmetric to each other in the longitudinal cross-section passing through the center of the housing cover 30.

[0080] With reference to Fig. 8. The upper notched section N1 and the lower notched section N2 can be configured to be point-symmetric to each other in the longitudinal cross-section passing through the center of the housing cover 30, based on the intersection of the first straight line SL and the second straight line PL. That is, the shape of the upper notched section N1 and the shape of the lower notched section N2 can be configured to be substantially the same. According to this structure, since the notched sections N1 and N2 have inclined shapes, a shear stress can be exerted on the area between the upper notched section N1 and the lower notched section N2.

[0081] In another aspect of the present disclosure, in the longitudinal cross-section passing through the center of the housing cover 30, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 can be configured to be larger than the shortest distance D1 between the upper notched section N1 and the lower notched section N2 in the case where the upper notched section N1 and the lower notched section N2 are provided at the same position in the radial direction.

[0082] In the case where the upper notched section N1 and the lower notched section N2 are on the same line as in Fig. Since 5 are provided, a tensile stress can be exerted on the area between the upper notched section N1 and the lower notched section N2, thus increasing the venting pressure required to interrupt the venting section 31. Therefore, in order to reduce the venting pressure, the thickness of the area between the upper notched section N1 and the lower notched section N2 must be reduced by increasing the dimensions of the notched sections. That is, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 must be reduced in the longitudinal cross-section passing through the center of the housing cover 30. However, in this case, the degree of deformation may increase, thereby increasing the risk of damage to the forming tools. This may reduce the service life of the housing cover 30.

[0083] On the other hand, according to the structure in which the upper notched section N1 and the lower notched section N2 are provided in the offset state, as in Fig. As shown in Figure 8, a shear stress is predominantly applied to the area between the upper notched section N1 and the lower notched section N2. For the same magnitude of pressure, the vent section is more likely to fracture under shear stress compared to tensile stress, thus making it possible to maintain the same venting pressure with a lower degree of deformation. That is, even if the shortest distance D1 between the upper notched section N1 and the lower notched section N2 in the longitudinal cross-section passing through the center of the housing cover 30 is increased more than in the case shown in Figure 8, the venting pressure can be maintained with a lower degree of deformation. Fig. 5. It may be possible to ensure the same venting pressure. Consequently, damage to mold tools can be reduced by decreasing the degree of deformation, which is expected to increase the service life of the housing cover 30.

[0084] In another aspect of the present disclosure, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 in the longitudinal cross-section passing through the center of the housing cover 30 can be configured to be smaller than the thickness of the housing cover 30.

[0085] For example, with reference to Fig. 8. The shortest distance D1 between the upper notched section N1 and the lower notched section N2 may be less than the thickness of the housing cover 30. Furthermore, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 may be less than the maximum width of the notched sections N1 and N2.

[0086] If the shortest distance D1 between the upper notched section N1 and the lower notched section N2 is configured to be too large, the thickness of the area between the upper notched section N1 and the lower notched section N2 may increase, thus further increasing the venting pressure required to interrupt the vent section 31. Therefore, as described above, it is preferred that the shortest distance D1 between the upper notched section N1 and the lower notched section N2 be configured to be at or below a certain level.

[0087] In another aspect of the present disclosure, the area in which the upper notched section N1 is formed and the area in which the lower notched section N2 is formed can be configured to overlap each other at least partially in a direction perpendicular to the housing cover 30. For example, with reference to Fig. 6 and Fig. 7. The area in which the upper notched section N1 is formed and the area in which the lower notched section N2 is formed may be configured to overlap each other at least partially in the direction substantially perpendicular to the housing cover 30, that is, in the direction upwards and downwards in the drawing. According to this structure, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 may be configured within a predetermined range. If the area in which the upper notched section N1 is formed and the area in which the lower notched section N2 is formed do not overlap each other in the direction substantially perpendicular to the housing cover 30, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 may increase excessively.In this case, the thickness of the area between the upper notched section N1 and the lower notched section N2 can increase, further increasing the venting pressure required to interrupt the venting section 31. Therefore, as described above, it is preferred that the area in which the upper notched section N1 is formed and the area in which the lower notched section N2 is formed are configured to at least partially overlap each other along a direction substantially perpendicular to the housing cover 30.

[0088] In another aspect of the present disclosure, it is preferred that the shortest distance between the upper notched section N1 and the lower notched section N2 is greater than 10% of the thickness of the housing cover 30.

[0089] For example, according to one embodiment of the present disclosure, the venting pressure of a battery cell 1 of a particular design, which has a casing cover 30 made of SUS430 and having a thickness of 0.7 t, may be required to reach approximately 17 kgf / cm². To obtain the above venting pressure, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 must be approximately 0.070 mm, which is approximately 10% of the thickness of the casing cover 30. If, as described above, the shortest distance D1 between the upper notched section N1 and the lower notched section N2 is less than or equal to the above level, it is very likely that the forming tools will be damaged during deformation, thereby reducing the service life of the casing cover 30.Therefore, it is preferred that the shortest distance D1 between the upper notched section N1 and the lower notched section N2 is greater than 10% of the thickness of the housing cover 30.

[0090] Fig. Figure 9 is a diagram illustrating the interruption process of the venting section 31 according to a comparative example in the present disclosure, and Fig. Figure 10 is a diagram illustrating the interruption process of the venting section 31 according to an embodiment of the present disclosure.

[0091] With reference to Fig. 9 In the conventional housing cover 30, the upper notched section N1 and the lower notched section N2 can be arranged on the same line. In this case, the stress is exerted in one direction of arrow A on the area between the upper notched section N1 and the lower notched section N2. In this case, the tensile stress can be predominantly exerted in direction A.

[0092] On the other hand, with reference to Fig. 10 in the housing cover 30 according to an embodiment of the present disclosure, since the upper notched section N1 and the lower notched section N2 are provided in the offset state, the stress in one direction of arrow B is exerted on the area between the upper notched section N1 and the lower notched section N2. In this case, the shear stress can be dominant in direction B. For the same magnitude of pressure, the vent section is more likely to rupture when a shear stress is applied compared to when a tensile stress is applied. Therefore, according to the present disclosure, the vent section 31 can rupture even if a lower venting pressure is applied to it.Alternatively, as in the present disclosure, if the upper notched section N1 and the lower notched section N2 are in the offset state, it may be possible to ensure the same venting pressure even with a lower degree of deformation. As a result, damage to mold tools can be reduced by decreasing the degree of deformation, which is expected to increase the service life of the housing cover 30.

[0093] With reference to Fig. 1 and Fig. 2. According to one embodiment of the present disclosure, the collector 40 is received within the battery housing 20, is electrically connected to the electrode arrangement 10, and is also electrically connected to the battery housing 20. That is to say, the collector 40 electrically connects the electrode arrangement 10 and the battery housing 20.

[0094] With reference to Fig. Figure 11 of a battery pack 3, according to one embodiment of the present disclosure, comprises a battery arrangement in which several battery cells 1, according to an embodiment of the present disclosure described above, are electrically connected, and a pack housing 2 that accommodates them. For the sake of clarity, components such as a busbar for electrical connection, a cooling unit, and power terminals are omitted from the drawings of the present disclosure. That is to say, the battery pack 3 may also include elements of the battery pack 3 that are known at the time of filing of the present disclosure, such as a BMS, a pack housing, a relay, a current sensor, and the like.

[0095] With reference to Fig.12. A vehicle 5 according to one embodiment of the present disclosure can, for example, be an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle and may include the battery pack 3 according to one embodiment of the present disclosure. The vehicle 5 comprises a four-wheeled vehicle and a two-wheeled vehicle. The vehicle 5 operates by receiving power from the battery pack 3 according to one embodiment of the present disclosure. The vehicle 5 according to the present disclosure may further comprise various other elements that are included in the vehicle 5 in addition to the battery pack 3. For example, the vehicle 5 according to the present disclosure may further comprise a vehicle body, an engine, a control device such as an electronic control unit (ECU), and the like, in addition to the battery pack 3 according to the present disclosure.

[0096] Although this description uses terms that indicate directions such as up and down, it is obvious to experts in the field that these terms are only used to simplify the explanation and may vary depending on the position of the target object or the position of the observer.

[0097] Although the present disclosure has been described with reference to limited embodiments and drawings, the present disclosure is not limited thereto, and various modifications and variations are possible for the person skilled in the art in the field to which the present disclosure relates, within the technical intent of the present disclosure and the scope of equivalence of the claims below. [Description of reference symbols] 5 vehicles 3 battery packs 2 Pack cases 1 battery cell 10 Electrode arrangement 20 battery cases 21 Corrugated section 22 Crimp section 30 Case Covers 31 Ventilation section N1 upper notched section N2 lower notched section G1 seal QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] KR 10-2022-0157708

[0002]

Claims

[1] comprising a battery cell: an electrode arrangement comprising a first electrode, a second electrode and a separator arranged between them; a battery housing configured to receive the electrode assembly through an opening formed on one side thereof; and a housing cover configured to cover the opening and featuring a vent section configured to rupture when the internal pressure of the battery housing rises to a predetermined level or higher, wherein the venting section has an upper notched section provided on the upper surface of the housing cover and a lower notched section provided on the lower surface of the housing cover, and wherein the upper notched section and the lower notched section are provided in an offset state. [2] Battery cell according to claim 1, wherein the venting section forms a circular closed ring. [3] Battery cell according to claim 1, wherein the center line of the upper notched section and the center line of the lower notched section are spaced apart from each other in the radial direction by a predetermined distance. [4] Battery cell according to claim 1, wherein the upper notched section is provided further inwards in the radial direction than the lower notched section. [5] Battery cell according to claim 1, wherein the upper notched section and the lower notched section are configured such that their widths decrease towards the inside of the housing cover from the surface thereof. [6] Battery cell according to claim 1, wherein the upper notched section has an axisymmetric structure to have an inclination relative to the center line of the upper notched section, and wherein the lower notched section has an axisymmetric structure to have an inclination relative to the center line of the lower notched section. [7] Battery cell according to claim 1, wherein, defining a first straight line SL, which is a fictitious straight line passing through the shortest distance between the upper notched section and the lower notched section, and a second straight line, which is a fictitious straight line perpendicular to the first straight line in the longitudinal cross-section passing through the center of the housing cover, the angle formed between the second straight line and the surface of the housing cover is greater than 0 degrees and less than 90 degrees. [8] Battery cell according to claim 1, wherein, assuming that the width of the inlet of the upper notched section is W1 and that the width of the inlet of the lower notched section is W2, the distance between the center line of the upper notched section and the center line of the lower notched section satisfies the following equation 1 0 <D2<W1+W22 [9] Battery cell according to claim 1, wherein the upper notched section and the lower notched section are configured to be point-symmetric to each other in the longitudinal cross-section passing through the center of the housing cover. [10] Battery cell according to claim 1, wherein in the longitudinal cross-section passing through the center of the housing cover, the shortest distance between the upper notched section and the lower notched section is greater than the shortest distance between the upper notched section and the lower notched section in the case where the upper notched section and the lower notched section are provided at the same position in the radial direction. [11] Battery cell according to claim 1, wherein in the longitudinal cross-section passing through the center of the housing cover the shortest distance between the upper notched section and the lower notched section is less than the thickness of the housing cover. [12] Battery cell according to claim 1, wherein a region where the upper notched section is formed and a region where the lower notched section is formed overlap each other at least partially in a direction perpendicular to the housing cover. [13] Battery cell according to claim 1, wherein the shortest distance between the upper notched section and the lower notched section is greater than 10% of the thickness of the housing cover. [14] Battery pack comprising at least one battery cell according to any one of claims 1 to 13. [15] Vehicle comprising at least one battery pack according to claim 14.

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