Secondary battery

Abstract

The present disclosure provides a secondary battery including: a case in which an electrode assembly is accommodated; the cover plate seals the opening of the shell; and an exhaust port provided in one or more of the housing and the cover plate, the exhaust port including: a notch induced to break according to an internal pressure of the housing; and a plurality of bending guides for inducing rolling deformation of each fractured region. The present disclosure can appropriately secure and maintain a discharge port area after the discharge port is broken by rolling up the discharge port.

Description

Technical Field

[0001] The present disclosure relates to a secondary battery capable of charging and discharging. Background Art

[0002] A secondary battery is an energy storage device capable of charging and discharging. Secondary batteries are widely used in various devices powered by electricity. For example, secondary batteries are used as energy storage devices in various devices from small devices such as mobile phones, laptops, and tablets to large devices such as vehicles and aircraft. In particular, in recent years, there has been active exploration of using secondary batteries as a power source for vehicles.

[0003] According to the different electrode materials, secondary batteries can be classified into lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, etc. Various types of secondary batteries can be appropriately selected according to the design capacity, use environment, etc. Compared with other types of secondary batteries, lithium-ion batteries can achieve relatively high voltages and capacities. Therefore, lithium-ion batteries are widely used in fields that require high-density energy storage devices such as vehicle battery packs.

[0004] The main components of secondary batteries such as lithium-ion batteries include a positive electrode material, a negative electrode material, a separator, an electrolyte, etc. A separator made of an insulating material is provided between the positive electrode material and the negative electrode material, and charging or discharging can be performed through the movement of ions in the electrolyte.

[0005] On the other hand, if excessive heat or electrolyte decomposition occurs due to damage to the insulation structure caused by overcharging, foreign object insertion, or external impact, the internal pressure of the secondary battery may rise, resulting in the secondary battery catching fire or exploding. Therefore, some types of secondary batteries include a vent for discharging excessive internal pressure, etc. For example, Patent Publication No. 10-2023-0048765 discloses a secondary battery including such a vent (safety vent).

[0006] The above description is provided to help understand the technical background of the present disclosure and should not be construed as narrowing, limiting, or restricting the technical idea of the present disclosure. In addition, the content described or recited in the above description does not necessarily mean prior art and may also include content that is not prior art. Summary of the Invention

[0007] (I) Technical Problem to be Solved

[0008] According to one aspect of the present disclosure, a secondary battery can be provided that improves the function of discharging internal pressure through a vent, etc.

[0009] However, the technical problems to be solved by the embodiments of the present disclosure are not necessarily limited to the above technical problems. Those of ordinary skill in the art to which the present disclosure pertains can clearly understand other technical problems not mentioned from other descriptions in the detailed description and other parts of the specification.

[0010] The secondary battery of the present disclosure can be widely applied to electric vehicles, battery charging stations, and other green technology fields such as solar power generation and wind power generation that utilize batteries. In addition, the secondary battery of the present disclosure can be used in eco-friendly electric vehicles (Electric Vehicle), hybrid vehicles, etc. that prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0011] (II) Technical Solution

[0012] The secondary battery according to the present disclosure may include: a case that internally accommodates an electrode assembly; a cover plate that closes an opening of the case; and an exhaust port provided in one or more of the case and the cover plate, and the exhaust port may include: a notch that is induced to break according to an internal pressure of the case; and one or more bending guide portions that induce a roll-up deformation of each region where the break occurs.

[0013] According to one embodiment, the notch may include: a first notch that extends along a first direction on an outer side surface of the exhaust port, and a pair of first notches are spaced apart in a second direction; and a second notch that extends between the pair of first notches.

[0014] According to one embodiment, the second notch may be provided to equally divide the first notch into left and right parts along the first direction, and the second notch may extend along a second direction orthogonal to the first direction.

[0015] According to one embodiment, the second notch may extend obliquely at a predetermined angle with the first notch between the pair of first notches.

[0016] According to one embodiment, the first notch may have a first depth starting from the outer side surface, the second notch may have a second depth starting from the outer side surface, and the second depth may be greater than the first depth by a predetermined degree.

[0017] According to one embodiment, the notch may be in an H shape on a plane.

[0018] According to one embodiment, the bending guide portion may induce each region to roll toward the outer side surface of the exhaust port and deform.

[0019] According to one embodiment, the bending guide portion may be formed by being recessed and bent toward the inside of the housing and extending in a second direction, and a plurality of the bending guide portions may be spaced apart from each other at a predetermined interval in a first direction orthogonal to the second direction.

[0020] According to one embodiment, one end of the bending guide portion in the second direction may be spaced apart from the notch by a predetermined interval, and an opposite side end portion opposite to the one end may be spaced apart from the notch by a predetermined interval.

[0021] According to one embodiment, the bending guide portion may include a first bending guide portion disposed in a first region divided by the second notch, the first bending guide portion being formed to extend in the second direction, a plurality of the first bending guide portions being spaced apart from each other at a predetermined interval in the first direction, and the first bending guide portion inducing the first region to be rolled and deformed toward one side.

[0022] According to one embodiment, the distance between a pair of first bending guide portions closer to the second notch among the first bending guide portions may be larger than the distance between another pair of first bending guide portions farther from the second notch by a predetermined degree.

[0023] According to one embodiment, the bending guide portion may include a second bending guide portion disposed in a second region corresponding to the first region, the second bending guide portion being formed to extend in the second direction, a plurality of the second bending guide portions being spaced apart from each other at a predetermined interval in the first direction, and the second bending guide portion inducing the second region to be rolled and deformed toward the opposite side opposite to the one side.

[0024] (III) Advantageous Effects

[0025] According to one embodiment of the present disclosure, it is possible to ensure and maintain an appropriate area of the discharge port after the exhaust port is broken by rolling up the exhaust port. In some cases, this may help to quickly and stably control heat, pressure, by-products, etc. inside the secondary battery.

[0026] In addition, according to one embodiment of the present disclosure, it is possible to appropriately cope with changes in the internal pressure of the housing through the bending guide portion. That is, in the embodiment of the present disclosure, the bending guide portion may receive an internal pressure within an allowable value before the exhaust port is broken and induce appropriate elastic deformation. The bending guide portion can prevent unnecessary fatigue loads from accumulating in the notch, and at the same time can serve to limit the elastic deformation direction of the exhaust port to a predetermined direction.

[0027] However, the technical effects obtainable through the embodiments of the present disclosure are not necessarily limited to the above effects. Those of ordinary skill in the art to which the present disclosure pertains can clearly understand other technical effects not mentioned from other descriptions in the detailed description and other parts of the specification. Brief Description of the Drawings

[0028] Figure 1a is a schematic perspective view of the exterior of a secondary battery according to one embodiment.

[0029] Figure 1b is Figure 1a a schematic exploded perspective view of the secondary battery shown.

[0030] Figure 1c is Figure 1a a schematic internal cross-sectional view of the secondary battery shown taken along 1c - 1c'.

[0031] Figure 2a is a schematic perspective view of an exhaust port according to one embodiment.

[0032] Figure 2b is Figure 2a a schematic cross-sectional view of the exhaust port shown taken along C1 - C1'.

[0033] Figure 2c is Figure 2a a schematic operating view of the exhaust port shown.

[0034] Figure 3a is a schematic perspective view of an exhaust port according to another embodiment.

[0035] Figure 3b is Figure 3a a schematic cross-sectional view of the exhaust port shown taken along C2 - C2'.

[0036] Figure 4a is a schematic perspective view of an exhaust port according to yet another embodiment.

[0037] Figure 4b is Figure 4a a schematic cross-sectional view of the exhaust port shown taken along C3 - C3'.

[0038] Figure 5 is a schematic perspective view of an exhaust port according to yet another embodiment.

[0039] Description of the Reference Numerals:

[0040] 100: Secondary battery

[0041] 110: Case

[0042] 120: Electrode assembly

[0043] 130: Cover plate

[0044] 200: Exhaust port

[0045] 210: Outer side surface

[0046] 220: Inner side surface

[0047] 230: First notch

[0048] 240: Second notch

[0049] 250: First bending guide portion

[0050] 260: Second bending guide portion Detailed implementation manners

[0051] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. For convenience, in the following description, detailed descriptions of configurations that obscure the technical gist of the present disclosure or known configurations will be omitted.

[0052] The following embodiments are provided to more completely describe the present disclosure to ordinary technicians in the technical field to which the present disclosure pertains. The following embodiments are provided to assist in understanding the present disclosure, and the technical idea of the present disclosure is not limited to the specific embodiments described below. The present disclosure should be understood to broadly include various equivalents, alternatives, transformants, etc. that implement the technical idea described in the following embodiments.

[0053] The terms used in the following embodiments are provided to more completely describe specific embodiments from the above viewpoints. Therefore, the terms used in the following embodiments should not be construed as aiming to narrow, limit, or restrict the technical idea of the present disclosure.

[0054] In the following description, unless clearly excluded in the context, singular expressions can be interpreted to include plural. Additionally, in the following description, the expression "including" means that the described structures, components, operations, features, steps, numbers, etc. exist, and does not mean excluding the addition of one or more other structures, components, operations, features, steps, numbers, etc.

[0055] In the following description, terms such as "first", "second", etc. can be used to distinguish a specific component from other components. However, the purpose of using the said terms is to distinguish a specific component from other components for the sake of clear description, and the technical idea of each component should not be construed as being limited by the said terms.

[0056] The secondary battery described in this specification may include a battery capable of charging and discharging. For example, the secondary battery may include a lead-acid battery, a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-ion battery, etc. In this specification, it is assumed that the secondary battery is a lithium-ion battery. Generally, a lithium-ion battery may have advantages such as light weight, high energy density, and low self-discharge rate. However, it should be understood that the technical concepts described in this specification may also be applicable to other suitable types of batteries other than lithium-ion batteries.

[0057] The secondary battery described in this specification may include a single physical unit cell or a cluster unit formed by combining multiple said unit cells. For example, according to the classification criteria commonly used in the current vehicle field, the secondary battery may include a battery cell, a battery module, a battery pack, etc. In this specification, it is assumed that the secondary battery is a single unit cell, i.e., a battery cell. Generally, a battery cell is the basic component unit of a battery pack including a positive electrode material, a negative electrode material, a separator, an electrolyte, etc. However, it should be understood that the technical concepts described in this specification may be applicable to other suitable types of cluster units such as battery modules and battery packs as needed.

[0058] The secondary battery described in this specification may include various packaging types. For example, according to the classification criteria commonly used in the relevant field currently, the secondary battery may be packaged into a cylindrical shape, a prismatic shape, a pouch shape, a coin shape, etc. In this specification, it is assumed that the secondary battery is packaged into a prismatic shape. The prismatic packaging, such as a prismatic battery, generally has advantages in terms of durability, safety, installation convenience, etc. However, it should be understood that the technical concepts described in this specification may be applicable to other suitable packaging types such as cylindrical, pouch, coin shapes, etc. as needed.

[0059] The secondary battery described in this specification may be used in various devices that require electrical energy. For example, the secondary battery may be applicable to the vehicle field where electrical energy is used as the main power source or auxiliary power source. As another example, the secondary battery may be applicable to the aircraft field such as personal aircraft, drones, unmanned aerial vehicles, etc., the electronic device field such as mobile phones, laptops, tablets, etc., and the power tool field such as electric drills, electric grinders, electric hammers, etc. However, it should be understood that the secondary battery described in this specification may be widely applied to various devices that operate based on electrical energy other than the above.

[0060] Figure 1a is a schematic external three-dimensional view of a secondary battery according to an embodiment. Figure 1b is Figure 1a a schematic exploded three-dimensional view of the secondary battery shown. Figure 1c is Figure 1aSchematic internal cross-sectional view of the secondary battery taken along 1c-1c'.

[0061] For ease of explanation, in this embodiment, one battery cell encapsulated in a prismatic shape is shown.

[0062] Refer to Figures 1a to 1c , the secondary battery 100 according to this embodiment may include a housing 110.

[0063] The housing 110 may provide an internal space capable of accommodating the electrode assembly 120 and the like. In this embodiment, the housing 110 is shown to be generally in the shape of a rectangular parallelepiped.

[0064] The housing 110 may include an opening 111 connected to the internal space. In this embodiment, the opening 111 is shown to be provided at the upper end of the housing 110. However, the position of the opening 111 may be changed as needed and is not necessarily limited to the illustrated example. The opening 111 may serve as a passage for inserting the electrode assembly 120 and the like. Additionally, the opening 111 may serve as a connection space for the electrical connection between the electrode assembly 120 and the electrode terminal. The opening 111 may be closed by a cover plate 130.

[0065] The material of the housing 110 may be appropriately selected considering thermal conductivity and electrical conductivity, rigidity corresponding to the swelling of the electrode assembly 120, processability, manufacturing cost, etc. For example, the housing 110 may be made of a metal material including aluminum, aluminum alloy, etc.

[0066] On the other hand, the secondary battery 100 according to this embodiment may include an electrode assembly 120.

[0067] The electrode assembly 120 may be disposed in the internal space of the housing 110. As needed, the electrode assembly 120 may be accommodated in an insulating bag 124 and disposed inside the housing 110.

[0068] The electrode assembly 120 may include a positive electrode material 121. The positive electrode material 121 may include a positive electrode current collector and a positive electrode active material. In some embodiments, the positive electrode current collector may include aluminum, aluminum alloy, etc., and the positive electrode active material may include lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, lithium iron phosphate, etc. The positive electrode active material may be coated on the surface of the positive electrode current collector. A part of the positive electrode current collector not coated with the positive electrode active material may be used as a positive electrode terminal 121a. In some embodiments, a plurality of positive electrode terminals 121a may be provided, and some or all of the plurality of positive electrode terminals 121a may be connected to each other.

[0069] The electrode assembly 120 may include a negative electrode material 122. The negative electrode material 122 may include a negative electrode current collector and a negative electrode active material. In some embodiments, the negative electrode current collector may include copper, copper alloy, nickel, nickel alloy, etc., and the negative electrode active material may include carbon, silicon, etc. The negative electrode active material may be coated on the surface of the negative electrode current collector. A part of the area of the negative electrode current collector without the coated negative electrode active material may be used as the negative electrode terminal 122a. In some embodiments, a plurality of negative electrode terminals 122a may be provided, and some or all of the plurality of negative electrode terminals 122a may be connected to each other.

[0070] The electrode assembly 120 may include a separator 123. The separator 123 may be disposed between the positive electrode material 121 and the negative electrode material 122. The separator 123 may serve to limit physical contact between the positive electrode material 121 and the negative electrode material 122 and provide a channel for ion movement. In some embodiments, the separator 123 may be made of a polymer material including polyethylene, polypropylene, etc. Additionally, the separator 123 may include a dry separator and a wet separator. In some embodiments, the separator 123 may include a coating, which includes a ceramic coating, etc.

[0071] The electrode assembly 120 may be formed by arranging the above components in a winding, stacking, or other manner. For example, the electrode assembly 120 may be formed in a structure where the positive electrode material 121, the negative electrode material 122, and the separator 123 are wound around a longitudinal axis or a transverse axis. Alternatively, the electrode assembly 120 may be formed in a structure where the above winding structure is compressed in a direction substantially perpendicular to the winding axis. The winding structure may be referred to as a "jelly roll" or the like in the art.

[0072] As another example, the electrode assembly 120 may be formed in a structure where the positive electrode material 121, the negative electrode material 122, and the separator 123 are stacked. In some cases, in the stacking structure, the separator 123 may be formed in a structure where a plurality of unit separators 123 that are continuous in the length direction are sequentially folded and stacked in the stacking order of the positive electrode material 121 and the negative electrode material 122. The stacking structure may be referred to as "stack and folding", "z-folding", etc. in the art. However, in this embodiment, the arrangement of each component of the electrode assembly 120 is not particularly limited. The electrode assembly 120 may have various arrangements other than the above examples.

[0073] In some embodiments, the electrode assembly 120 may be formed by combining multiple unit cells. For example, the electrode assembly 120 may include unit cells wound in a jelly roll manner, and two or more of the unit cells may be combined to form the electrode assembly 120. In this embodiment, the electrode assembly 120 is formed by combining two unit cells. As another example, the electrode assembly 120 may include unit cells wound in a stacked and folded manner, and two or more of the unit cells may be combined to form the electrode assembly 120.

[0074] The electrode assembly 120 may be accommodated in the internal space of the housing 110 together with the electrolyte. In some embodiments, the electrolyte may be formed of an organic solvent containing a lithium salt. For example, the lithium salt may include liquid or gel-like lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), etc., and the organic solvent may include cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC), and linear carbonates such as diethyl carbonate (DEC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC).

[0075] In some other embodiments, the electrolyte may be omitted or replaced. For example, when an inorganic solid electrolyte is used, the liquid or gel-like electrolyte may be omitted.

[0076] On the other hand, the secondary battery 100 according to this embodiment may include a cover plate 130.

[0077] The cover plate 130 may close the opening 111. In this embodiment, the cover plate 130 is shown in a quadrilateral plate shape corresponding to the opening 111. The cover plate 130 may be coupled to the housing 110 to seal the internal space of the housing 110 in which the electrode assembly 120 is disposed. In some embodiments, the cover plate 130 may be joined to the housing 110 by welding such as ultrasonic welding, laser welding, etc.

[0078] A positive terminal 131 and a negative terminal 132 may be provided on the cover plate 130. The positive terminal 131 may be electrically connected to the positive electrode joint 121a of the electrode assembly 120, and the negative terminal 132 may be electrically connected to the negative electrode joint 122a of the electrode assembly 120.

[0079] The cover plate 130 may include an electrolyte injection port 134. The electrolyte injection port 134 may be used to inject electrolyte into the internal space of the housing 110. In the present embodiment, the electrolyte injection port 134 is disposed adjacent to the exhaust port 133 in the central region of the cover plate 130. However, the position of the electrolyte injection port 134 may vary in various ways and is not necessarily limited to the illustrated example. The electrolyte injection port 134 may be appropriately sealed after processes such as electrolyte injection and formation. In some embodiments, the electrolyte injection port 134 may be sealed by pressing in a spherical sealing member made of a polymer resin.

[0080] The cover plate 130 may include an exhaust port 133. In the present embodiment, the exhaust port 133 is disposed between the positive terminal 131 and the negative terminal 132. However, the position of the exhaust port 133 may vary as needed and is not necessarily limited to the illustrated example. In some other embodiments, the exhaust port 133 may be disposed in the housing 110 or added to the housing 110.

[0081] The exhaust port 133 may be opened according to the internal pressure of the housing 110. The exhaust port 133 may function to discharge the internal pressure to the outside of the housing 110, thereby helping to stabilize the internal components of the housing 110. In the present embodiment, the exhaust port 133 may more appropriately respond to or discharge the internal pressure through components to be described later.

[0082] Figure 2a is a schematic perspective view of an exhaust port according to an embodiment. Figure 2b is Figure 2a a schematic cross-sectional view taken along C1-C1' of the illustrated exhaust port.

[0083] For convenience, new reference numerals are given to the exhaust ports according to the respective embodiments and described.

[0084] Refer to Figure 2a and Figure 2b , the exhaust port 200 according to the present embodiment may be disposed in one or more of the cover plate 130 and the housing 110. In the present embodiment, the case where the exhaust port 200 is disposed in the cover plate 130 is shown, and the following will be described centering on this. As a reference, the Figure 5 etc. show the case where the exhaust port 200 is disposed in the housing 110.

[0085] The exhaust port 200 according to the present embodiment may include an outer side surface 210 and an inner side surface 220. The outer side surface 210 refers to the surface facing the outside of the housing 110, and the inner side surface 220 refers to the surface facing the inside of the housing 110.

[0086] The exhaust port 200 according to the present embodiment can be formed to extend in a first direction E1 and a second direction E2. In the present embodiment, the first direction E1 is shown as a direction corresponding to the length direction E1 of the cover plate 130, and the second direction E2 is shown as a direction corresponding to the width direction E2 of the cover plate 130. The length of the cover plate 130 along the length direction E1 shown as a reference is greater than the length along the width direction E2. For convenience, hereinafter, the first direction E1 will be described as the length direction E1 and the second direction E2 as the width direction E2.

[0087] On the other hand, the exhaust port 200 according to the present embodiment can include notches 230, 240.

[0088] The notches 230, 240 can induce the exhaust port 200 to be fractured according to the internal pressure of the housing 110. That is, the notches 230, 240 can define the fracture positions of the exhaust port 200. The exhaust port 200 can be designed to fracture at positions corresponding to the notches 230, 240 to discharge the internal pressure.

[0089] The notches 230, 240 can be formed by recessing a predetermined degree in the thickness direction from the outer side surface 210 of the exhaust port 200 toward the inner side surface 220. The notches 230, 240 can be generally in the shape of grooves formed on the outer side surface 210 of the exhaust port 200. In addition, the notches 230, 240 can have a predetermined cross-sectional shape and extend along the length direction. In the present embodiment, the notches 230, 240 are shown as having a substantially "V" - shaped cross-sectional shape. The thickness of the portion where the notches 230, 240 are formed can be smaller than the thickness of the portion where the notches 230, 240 are not formed.

[0090] The notches 230, 240 can be formed by forming predetermined lines, patterns, etc. on the outer side surface 210 of the exhaust port 200 and extending. In some embodiments, the notches 230, 240 can be formed to extend along the length direction E1 or the width direction E2 of the exhaust port 200. Or, in some other embodiments, the notches 230, 240 can extend obliquely at a predetermined angle with respect to the length direction E1 or the width direction E2 of the exhaust port 200.

[0091] In this embodiment, the notches 230 and 240 may extend a predetermined length along the length direction E1 and the width direction E2 of the exhaust port 200, respectively. Specifically, the notches 230 and 240 may include a first notch 230 extending along the length direction E1. A pair of first notches 230 may be provided, and the pair of first notches 230 may be spaced apart by a predetermined distance in the width direction E2. In order to ensure sufficient opening space during fracture, the pair of first notches 230 may be sufficiently spaced apart in the width direction E2. In this embodiment, each first notch 230 is adjacent to the outer boundary line (edge) of the exhaust port 200 to ensure the spacing in the width direction E2.

[0092] In addition, the notches 230 and 240 may include a second notch 240 extending along the width direction E2. The second notch 240 may be formed to extend along the width direction E2 between the pair of first notches 230. One end of the second notch 240 may form a contact point with the first notch 230 on one side, and the other end may form a contact point with the first notch 230 on the other side. In this embodiment, the second notch 240 is arranged to be substantially orthogonal to the first notch 230 to form a contact point.

[0093] In some embodiments, the length of the second notch 240 may be different from the length of the first notch 230. In this embodiment, the length of the second notch 240 may be shorter than the length of the first notch 230 by a predetermined degree. In addition, the second notch 240 may be provided at the center of the first notch 230 in the length direction. That is, the second notch 240 may be arranged to bisect the first notch 230 extending along the length direction E1 into left and right parts. In this embodiment, the first notch 230 and the second notch 240 as described above are substantially in an "H" shape on the plane.

[0094] The second notch 240 may divide the first region A1 and the second region A2. The first region A1 refers to the region on one side of the second notch 240 along the length direction E1 of the exhaust port 200, and the second region A2 refers to the region on the opposite side of the said one side region. Based on the illustration, the exhaust port 200 may be divided into the first region A1 and the second region A2. The first region A1 is the region on the right side of the second notch 240, and the second region A2 is the region on the left side corresponding to the right side region of the second notch 240.

[0095] As needed, the first notch 230 and the second notch 240 may have different depths. Specifically, the first notch 230 may have a first depth D1 starting from the outer side surface 210, and the second notch 240 may have a second depth D2 that is a predetermined degree greater than the first depth D1. In some embodiments, the depth difference between the first notch 230 and the second notch 240 as described above may be achieved by the pressing force of the stamping machine applied when forming the first notch 230 and the second notch 240. In the above case, the second notch 240 may break before the first notch 230. That is, according to some operation examples, as the internal pressure of the housing 110 increases, the breakage of the second notch 240 portion may be induced first, and then the breakage of the first notch 230 portion may be induced.

[0096] On the other hand, the exhaust port 200 according to the present embodiment may include bending guide portions 250, 260.

[0097] When the notches 230, 240 break, the bending guide portions 250, 260 may serve to induce appropriate deformation of the respective regions A1, A2. In addition, the bending guide portions 250, 260 may serve to absorb temporary changes in the internal pressure of the housing 110 before the notches 230, 240 break to reduce unnecessary stress applied to the notches 230, 240.

[0098] The bending guide portions 250, 260 may be recessed and bent toward the inside of the housing 110. That is, the bending guide portions 250, 260 may be formed by being recessed and bent toward the inside of the housing 110 through the outer side surface 210 of the exhaust port 200. When the outer side surface 210 is recessed and bent, the corresponding inner side surface 220 may protrude toward the inside of the housing 110.

[0099] The bending guide portions 250, 260 may have a predetermined cross-sectional shape and be formed to extend in the width direction E2 of the exhaust port 200. In the present embodiment, the bending guide portions 250, 260 are shown as having a partial arc-shaped cross-sectional shape. However, the cross-sectional shape of the bending guide portions 250, 260 may vary as needed and is not necessarily limited to the illustrated example, as long as the functional elements of the bending guide portions 250, 260 described later can be satisfied. In some alternative embodiments, the bending guide portions 250, 260 may be achieved by materials, thicknesses, etc. rather than structures, shapes, etc.

[0100] The bending guide portions 250 and 260 can be formed to extend in the width direction E2 between a pair of first notches 230. Additionally, the bending guide portions 250 and 260 can be formed to extend in the width direction E2 to occupy most of the spacing G1 between the pair of first notches 230. For example, the bending guide portions 250 and 260 can be formed to extend in the width direction E2 to occupy more than 80% of the spacing Gl between the pair of first notches 230. In this embodiment, the bending guide portions 250 and 260 intersect the pair of first notches 230 in the width direction E2 and are formed to extend in the width direction E2 to completely occupy the spacing G1 between the pair of first notches 230.

[0101] A plurality of bending guide portions 250 and 260 can be provided, and the plurality of bending guide portions 250 and 260 can be spaced apart at a predetermined interval in the direction in which the first notch 230 extends. That is, the plurality of bending guide portions 250 and 260 can be spaced apart along the length direction E1. However, the plurality of bending guide portions 250 and 260 can be appropriately omitted in the region where the second notch 240 is formed. That is, the plurality of bending guide portions 250 and 260 can be spaced apart from the second notch 240 at a predetermined interval to be provided in the remaining region of the exhaust port 200 where the second notch 240 is not formed.

[0102] Additionally, the bending guide portions 250 and 260 can include a first bending guide portion 250 and a second bending guide portion 260. The first bending guide portion 250 can be provided in the first region A1, and the second bending guide portion 260 can be provided in the second region A2. The first bending guide portion 250 and the second bending guide portion 260 can be formed to be the same or similar to each other, except for the setting positions.

[0103] A plurality of first bending guide portions 250 can be provided within the first region A1. The plurality of first bending guide portions 250 can be spaced apart along the length direction E1 of the exhaust port 200 within the first region A1. In this embodiment, two first bending guide portions 250 are shown. Similarly, a plurality of second bending guide portions 260 can be provided within the second region A2. The plurality of second bending guide portions 260 can be spaced apart along the length direction E1 of the exhaust port 200 within the second region A2. In this embodiment, two second bending guide portions 260 are shown. However, the number of the first bending guide portion 250 and the second bending guide portion 260 does not necessarily have to be the same, and according to needs, the number of the first bending guide portion 250 and the second bending guide portion 260 can be different.

[0104] The first bending guide portion 250 may be provided at a predetermined interval G2 from the second notch 240 or another adjacent first bending guide portion 250. In this embodiment, each interval G2 of the first bending guide portion 250 is shown to be the same. Similarly, the second bending guide portion 260 may be provided at a predetermined interval G3 from the second notch 240 or another adjacent second bending guide portion 260. In this embodiment, each interval G3 of the second bending guide portion 260 is shown to be the same. However, as needed, each interval G2 of the first bending guide portion 250 or each interval G3 of the second bending guide portion 260 may be different. This is shown in Figure 4a etc.

[0105] Referring to Figure 2b , the bending guide portions 250, 260 as described above can function to cope with temporary changes in the internal pressure of the housing 110. Specifically, the exhaust port 200 including a plurality of bending guide portions 250, 260 can be induced to elastically deform by a predetermined degree about the width direction E2 in response to temporary changes in the internal pressure of the housing 110. As a reference, in Figure 2b , for ease of understanding, the above elastic deformation is somewhat exaggerated.

[0106] As described above, the plurality of bending guide portions 250, 260 extending along the width direction E2 can appropriately assist the elastic deformation about the width direction E2. This prevents unnecessary fatigue loads from accumulating in the notches 230, 240. In addition, the plurality of bending guide portions 250, 260 extending along the width direction E2 can function to appropriately limit the deformation of the exhaust port 200 about the length direction E1. This simplifies the external forces, deformations, etc. that need to be considered in the design of the exhaust port 200, making it easy to optimize the design of materials, specifications, etc.

[0107] Figure 2c is Figure 2a a schematic operation diagram of the exhaust port shown.

[0108] Referring to Figure 2c , the exhaust port 200 can be appropriately opened according to the internal pressure of the housing 110. That is, the exhaust port 200 can break the portions of the notches 230, 240 according to the internal pressure of the housing 110 to form a kind of discharge port OP, and the internal pressure can be discharged through the discharge port OP.

[0109] Specifically, the exhaust port 200 can be opened by the breakage of the second notch 240 portion under the action of the internal pressure of the housing 110, and then the breakage of the first notch 230 portion. However, the breaking order of the first notch 230 and the second notch 240 is not necessarily limited to this.

[0110] In the exhaust port 200 that breaks at the first notch 230 and the second notch 240, the first region A1 and the second region A2 are respectively rolled toward the side ends in the longitudinal direction E1, thereby ensuring the discharge port OP. That is, the first region A1 can be induced to deform in the form of a roll (roll) through a plurality of first bending guide portions 250 to roll toward one side (right side). In addition, the second region A2 can be induced to deform in the form of a roll through a plurality of second bending guide portions 260 to roll toward the opposite side (left side). In the present embodiment, the first region A1 and the second region A2 can be induced to deform and roll toward the outer side surface 210 of the exhaust port 200 along the directions of the first bending guide portion 250 and the second bending guide portion 260. For convenience, in this description, the form in which the respective regions A1 and A2 are rolled toward the outer side surface 210 and deformed as described above is referred to as "roll up".

[0111] In the present embodiment, the first region A1 and the second region A2 are rolled up as described above so that a sufficient discharge port OP can be ensured after breaking at the first notch 230 and the second notch 240. That is, the first region A1 rolls to the right in the figure, and the second region A2 rolls to the left in the figure to ensure a sufficient discharge port OP area between the first region A1 and the second region A2. Therefore, the internal pressure of the housing 110 can be induced to be discharged more smoothly.

[0112] In addition, the first region A1 and the second region A2 rolled up as described above can reduce the generation of sharp edge portions after breaking. In the conventional exhaust port structure, sharp edges and the like are directly exposed after breaking, which may cause secondary damage to adjacent components. In addition, the first region A1 and the second region A2 rolled up as described above can reduce problems such as the first region A1 and the second region A2 deforming again after breaking and hindering the discharge of the internal pressure.

[0113] Figure 3a It is a schematic perspective view of an exhaust port according to another embodiment. Figure 3b It is Figure 3a The schematic cross-sectional view taken along C2-C2' of the exhaust port shown.

[0114] For convenience, the following embodiments will focus on the differences from the above embodiments.

[0115] Referring to Figure 3a and Figure 3b According to the exhaust port 300 of the present embodiment, it may include notches 330 and 340.

[0116] The notches 330 and 340 may include a pair of first notches 330 extending along the longitudinal direction E1 of the exhaust port 300 and a second notch 340 extending along the width direction E2 between the pair of first notches 330. The second notch 340 may be disposed substantially orthogonally to the first notch 330 and may be disposed at the longitudinal center of the first notch 330. The notches 330 and 340 as described above are substantially similar to the above-described embodiments.

[0117] On the other hand, the exhaust port 300 according to the present embodiment may include curved guiding portions 350 and 360.

[0118] The curved guiding portions 350 and 360 may be formed by the outer side surface 310 of the exhaust port 300 being recessed and curved toward the inside of the housing 110. Additionally, the curved guiding portions 350 and 360 may be formed to extend along the width direction E2 between the pair of first notches 330.

[0119] Here, the curved guiding portions 350 and 360 of the present embodiment may be formed to be shorter than the distance G1 between the pair of first notches 330 by a predetermined degree. One end of the curved guiding portion 350 and 360 may be separated from the first notch 330 on one side by a predetermined distance G4, and the opposite end portion of the curved guiding portion 350 and 360 may be separated from the corresponding first notch 330 on the opposite side by a predetermined distance G5. That is, both ends of the curved guiding portions 350 and 360 of the present embodiment may be spaced apart from the first notch 330.

[0120] The setting of the curved guiding portions 350 and 360 as described above takes into account the smooth fracture of the first notch 330. That is, the setting of the curved guiding portions 350 and 360 as described above can remove the contact portion between the curved guiding portions 350 and 360 and the first notch 330, thereby excluding the unexpected strengthening effect of the contact portion.

[0121] For the above reasons, the curved guiding portions 350 and 360 of the present embodiment may be formed to be larger than the curved guiding portions 250 and 260 of the above-described embodiment. That is, referring to Figure 3b , the curved guiding portions 350 and 360 of the present embodiment may have a width W1 and a depth D3 that are larger than those of the curved guiding portions 250 and 260 of the above-described embodiment by a predetermined degree. Since the curved guiding portions 350 and 360 of the present embodiment do not form a contact point with the first notch 330, their shape, size, setting, etc. can be determined with a higher degree of design freedom.

[0122] On the other hand, the bending guide portions 350 and 360 may include a first bending guide portion 350 provided in the first region A1 and a second bending guide portion 360 provided in the second region A2. A plurality of first bending guide portions 350 may be provided, and in this embodiment, three first bending guide portions 350 are shown. Similarly, a plurality of second bending guide portions 360 may be provided, and in this embodiment, three second bending guide portions 360 are shown. Additionally, in this embodiment, each spacing G2 of the first bending guide portions 350 may be the same and each spacing G3 of the second bending guide portions 360 may be the same. This is substantially similar to the above-described embodiment.

[0123] Figure 4a is a schematic perspective view of an exhaust port according to another embodiment of the present disclosure. Figure 4b is Figure 4a a schematic cross-sectional view taken along C3-C3' of the exhaust port shown.

[0124] Referring to Figure 4a and Figure 4b according to this embodiment, the exhaust port 400 may include notches 430 and 440.

[0125] The notches 430 and 440 may include a pair of first notches 430 extending along the length direction E1 of the exhaust port 400 and a second notch 440 extending between the pair of first notches 430 along the width direction E2. These notches 430 and 440 are substantially similar to the above-described embodiment.

[0126] On the other hand, the exhaust port 400 according to this embodiment may include bending guide portions 450 and 460.

[0127] The bending guide portions 450 and 460 may be formed by being recessed and bent from the outer side surface 410 of the exhaust port 400 toward the inside of the housing 110. Additionally, the bending guide portions 450 and 460 may be formed to extend along the width direction E2 between the pair of first notches 430. Additionally, both ends of the bending guide portions 450 and 460 may be spaced apart from the first notches 430 by a predetermined distance G4 and G5. This is substantially similar to the above-described embodiment.

[0128] On the other hand, the bending guide portions 450 and 460 may include a plurality of first bending guide portions 450 provided in the first region A1 and a plurality of second bending guide portions 460 provided in the second region A2. In this embodiment, four first bending guide portions 450 and four second bending guide portions 460 are shown.

[0129] Here, the bending guide portions 450 and 460 of this embodiment can form different spacings according to their positions. Specifically, taking the second notch 440 as a reference, the four first bending guide portions 450 are referred to as the 1-1 bending guide portion 450-1 to the 1-4 bending guide portion 450-4. The 1-1 bending guide portion 450-1 can be separated from the second notch 440 by a first spacing G2-1, and the 1-2 bending guide portion 450-2 can be separated from the 1-1 bending guide portion 450-1 by a second spacing G2-2. Here, the second spacing G2-2 can be smaller than the first spacing G2-1 by a predetermined degree. Similarly, the third spacing G2-3 of the 1-3 bending guide portion 450-3, the fourth spacing G2-4 of the 1-4 bending guide portion 450-4, etc. can also gradually decrease. Additionally, similar to the above situation, the four second bending guide portions 460 can also have their spacings gradually decrease as they are separated from the second notch 240.

[0130] Referring to Figure 4b , the bending guide portions 450 and 460 set with different spacings as described above can induce more complete curling of the respective regions A1 and A2. That is, since the bending guide portions 450 and 460 are set to be closer to each other at positions farther from the second notch 440, the respective regions A1 and A2 can be curled in such a way that a smaller curvature is formed at positions farther from the second notch 440 and a larger curvature is formed at positions closer to the second notch 440. Thus, the exhaust port 400 of this embodiment can induce the respective regions A1 and A2 to curl more compactly and ensure a sufficient discharge port OP area when breaking.

[0131] Figure 5 is a schematic perspective view of an exhaust port according to another embodiment of the present disclosure.

[0132] Referring to Figure 5 , the exhaust port 500 according to this embodiment can be provided in the housing 110.

[0133] In this embodiment, the exhaust port 500 is disposed adjacent to a side corner portion at the lower end of the front surface of the housing 110. However, the position of the exhaust port 500 within the housing 110 can vary in various ways according to needs and is not necessarily limited to the illustrated example.

[0134] Except for the setting position, the exhaust port 500 according to the present embodiment may be substantially similar to the above embodiment. The exhaust port 500 may include notches 530 and 540. The notches 530 and 540 may include a pair of first notches 530 and a second notch 540 extending between the pair of first notches 530. Additionally, the exhaust port 500 may include curved guiding portions 550 and 560. The curved guiding portions 550 and 560 may include a plurality of first curved guiding portions 550 provided in the first region A1 and a plurality of second curved guiding portions 560 provided in the second region A2. In the present embodiment, three first curved guiding portions 550 and three second curved guiding portions 560 are respectively shown.

[0135] The difference between the exhaust port 500 of the present embodiment and the above embodiment lies in the configuration of the second notch 540. That is, the second notch 540 of the present embodiment may be formed to extend obliquely between the pair of first notches 530. This is in contrast to the second notches 240, 340, and 440 in the above embodiment which extend in a manner substantially orthogonal to the first notches 230, 330, and 430. In the present embodiment, the second notch 540 may extend at a predetermined angle S1 with respect to the pair of first notches 530, and the angle S1 may be set to a predetermined acute angle. For example, the second notch 540 may be set to form an angle S1 of 30 to 60 degrees with respect to the pair of first notches 530.

[0136] The second notch 540 as described above can induce a smoother fracture at the contact point with the first notch 530. That is, since the second notch 540 forms a predetermined acute angle with the first notch 530 and contacts it, an appropriate fracture can be induced at the acute angle portion according to the internal pressure of the housing 110. On the other hand, after the fracture, the fracture along the first notch 530 and the second notch 540 centered on the contact point is induced, so that the exhaust port 500 can be opened. Then, the first region A1 and the second region A2 of the exhaust port 500 are respectively rolled up by the first curved guiding portion 550 and the second curved guiding portion 560, thus having similar functions and effects as the above embodiment.

[0137] As described above, the secondary battery according to an embodiment of the present disclosure may include an exhaust port that is opened according to the internal pressure of the housing. In the exhaust port according to an embodiment of the present disclosure, each region centered on the notch can be induced to roll up and deform after fracture. That is, based on the second notch, the first region can be induced to roll up and deform to one side, and the second region on the opposite side can be induced to roll up and deform to the opposite side. The structure, shape of the notch, the curved guiding portions provided in each region, etc. proposed in the embodiments of the present disclosure can appropriately induce the above-mentioned rolling up and deformation.

[0138] The secondary battery according to an embodiment of the present disclosure can ensure and maintain an appropriate area of the discharge port after the exhaust port breaks by rolling up the exhaust port as described above. In some cases, this may help to quickly and stably handle heat, pressure, by-products, etc. inside the secondary battery.

[0139] In addition, the secondary battery according to an embodiment of the present disclosure can appropriately respond to changes in the internal pressure of the case through the bending guide portion. That is, in the embodiment of the present disclosure, the bending guide portion can receive the internal pressure within the allowable value before the exhaust port breaks and induce appropriate elastic deformation. The bending guide portion can prevent unnecessary fatigue load from accumulating in the notch and can also serve to limit the direction of the elastic deformation of the bending to a predetermined direction.

[0140] Although the embodiments of the present disclosure have been described above, those skilled in the art can make various modifications or changes to the present disclosure by adding, changing, deleting, or adding components without departing from the technical idea of the present disclosure described in the claims, and this will also be regarded as being included within the scope of the claims of the present disclosure.

Claims

1. A secondary battery comprising: A shell body, accommodating an electrode assembly therein; A cover plate, closing the opening of the housing; as well as an exhaust port, disposed in at least one of the housing and the cover plate, The exhaust port comprises: a notch, which is induced to break according to the internal pressure of the housing; as well as One or more bending guides induce rolling deformation of each region of the fracture.

2. The secondary battery according to claim 1, wherein The gaps include: A first notch is formed on the outer side of the exhaust port and extends along a first direction, and a pair of first notches are spaced apart in a second direction; and The second notch is extended and formed between the pair of first notches.

3. The secondary battery according to claim 2, wherein: The second notch is arranged to divide the first notch into left and right equal parts along the first direction, and the second notch is formed by extending along the second direction orthogonal to the first direction.

4. The secondary battery according to claim 2, wherein The second notch is formed between the pair of first notches and obliquely extends to form a predetermined angle with the first notch.

5. The secondary battery according to claim 2, wherein The first notch has a first depth from the outer side surface, The second notch has a second depth from the outer side surface, and the second depth is greater than the first depth by a predetermined degree.

6. The secondary battery according to claim 1, wherein The notch is in an H shape on a plane.

7. The secondary battery according to claim 1, wherein The bending guide portion induces each of the regions to roll toward the outer side surface of the exhaust port and deform.

8. The secondary battery according to claim 1, wherein The curved guide portion is concavely curved toward the inside of the housing and extends along the second direction, and a plurality of the curved guide portions are spaced apart at predetermined intervals in the first direction orthogonal to the second direction.

9. The secondary battery according to claim 8, wherein One end of the bending guide portion in the second direction is spaced apart from the notch by a predetermined distance, and an opposite side end portion opposite to the one end is spaced apart from the notch by a predetermined distance.

10. The secondary battery according to claim 2, wherein The bending guide portion includes a first bending guide portion, which is arranged in a first area divided by the second notch, the first bending guide portion is extended along the second direction, a plurality of the first bending guide portions are arranged at predetermined intervals in the first direction, and the first bending guide portion induces the first area to roll up and deform to one side.

11. The secondary battery according to claim 10, wherein The first bending guide portions are formed such that a distance between a pair of first bending guide portions closer to the second notch is greater than a distance between another pair of first bending guide portions farther from the second notch by a predetermined degree.

12. The secondary battery according to claim 10, wherein The bending guide portion includes a second bending guide portion, which is arranged in a second area corresponding to the first area, and the second bending guide portion is extended along the second direction. A plurality of second bending guide portions are arranged at predetermined intervals in the first direction, and the second bending guide portion induces the second area to roll up and deform toward an opposite side opposite to the one side.

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