Exhaust device and battery pack comprising same

Abstract

The invention provides an exhaust device and a battery pack including the same. An exhaust device includes: a cover located on one side of a wall in which an exhaust hole is formed to cover the exhaust hole through which gas can move; a connecting pin configured to pass through the wall and having one side connected to the cover; and a hook located on the other side of the wall and connected to the other side of the connecting pin such that the cover and the connecting pin are supported by the wall. The exhaust device of the present invention elastically deforms in response to an increase in the pressure inside the battery pack and allows gas to be released to the outside of the battery pack, and elastically recovers in response to a decrease in the pressure inside the battery pack caused by the gas release and prevents outside air from entering the battery pack.

Description

Technical Field

[0001] The invention relates to an exhaust device and a battery pack comprising the exhaust device. Background Art

[0002] A plurality of battery cells are accommodated in a case of the battery pack. During charge and discharge of the plurality of battery cells or due to an impact applied from the outside, gas containing flammable substances may be released from inside the battery cells to a space inside the case.

[0003] When the space inside the housing is filled with gas containing flammable substances, the battery pack may be deformed or damaged, or explode. Therefore, a venting device capable of releasing the gas inside the battery pack to the outside and reducing the pressure inside the battery pack is required.

[0004] The above information disclosed in this Background section is provided for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute related (or prior) art. Summary of the invention

[0005] The present invention relates to a vent device and a battery pack including the vent device, which allows gas to be released to the outside of the battery pack in response to an increase in pressure inside the battery pack and prevents external air from entering the battery pack in response to a decrease in pressure inside the battery pack caused by the gas release.

[0006] These and other aspects and features of the present disclosure will be described in or will be apparent from the following description of some embodiments of the present disclosure.

[0007] According to one aspect of the present invention, there is provided an exhaust device, comprising: a cover located on one side of a wall in which an exhaust hole is formed to cover the exhaust hole, through which gas can move; a connecting pin configured to pass through the wall and having one side connected to the cover; and a hook located on the other side of the wall and connected to the other side of the connecting pin, so that the cover and the connecting pin are supported by the wall.

[0008] The cover may include: a central portion coupled to the connection pin; and a peripheral portion configured to radially expand from the central portion and closely contact with one side surface of the wall to block the gas from moving through the exhaust hole.

[0009] When the other side pressure of the other side of the wall is higher than the one side pressure of the one side of the wall and the pressure difference between the other side pressure and the one side pressure is greater than the critical pressure of cover deformation, the cover can be elastically deformed so that the peripheral part is spaced apart from the one side surface of the wall.

[0010] When the pressure on the other side of the wall is higher than the pressure on the one side of the wall and the pressure difference between the pressure on the other side and the pressure on the one side is greater than the critical pressure for hook deformation, the hook can be elastically deformed so that the connecting pin moves to the one side of the wall and the peripheral portion of the cover is spaced apart from the surface of the one side of the wall.

[0011] When the pressure on the other side of the wall is higher than the pressure on one side of the wall and the pressure difference between the pressure on the other side and the pressure on the one side is greater than the critical pressure for deformation of the connecting pin, the connecting pin can be elastically deformed so that the length of the connecting pin is extended and the peripheral portion of the cover is spaced apart from the surface of one side of the wall.

[0012] The connecting pin may include: a cover connecting portion connected to the cover; a hook connecting portion connected to the hook; and an intermediate deformation portion located between the cover connecting portion and the hook connecting portion and having one side connected to the cover connecting portion and the other side connected to the hook connecting portion.

[0013] The intermediate deformation portion may include a plurality of leads bent to be elastically deformable in a non-bent direction.

[0014] The intermediate deformation portion may include a coil spring.

[0015] According to another aspect of the present disclosure, a battery pack is provided, comprising: a shell configured to define an internal space and having an exhaust hole formed therein, through which gas can move; at least one battery cell accommodated in the internal space; and an exhaust device comprising a cover positioned to cover the exhaust hole from the outside of the shell, a connecting pin configured to pass through the shell and connected to one side of the cover, and a hook located on the inside of the shell and connected to the other side of the connecting pin so that the cover and the connecting pin are supported by the shell.

[0016] The cover may include: a central portion coupled to the connection pin; and a peripheral portion configured to radially expand from the central portion and closely contact with an outer surface of the housing to block gas from moving through the exhaust hole.

[0017] When the internal pressure inside the shell is higher than the external pressure outside the shell and the pressure difference between the internal pressure and the external pressure is greater than the cover deformation critical pressure, the cover can be elastically deformed so that the outer peripheral part is spaced apart from the outer surface of the shell.

[0018] The separation distance between the outer surface and the outer peripheral portion may increase as the pressure difference between the internal pressure and the external pressure increases.

[0019] When the internal pressure inside the shell is higher than the external pressure outside the shell and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of hook deformation, the hook can be elastically deformed so that the connecting pin moves to the outside of the shell and the peripheral part of the cover is spaced apart from the outer surface of the shell.

[0020] When the internal pressure is higher than the external pressure and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of cover deformation, the cover can be elastically deformed so that the peripheral part is spaced apart from the outer surface of the shell, and the critical pressure of hook deformation can be higher than the critical pressure of cover deformation.

[0021] The hook may include a plurality of elastic spokes, each of the elastic spokes having one side coupled to the connecting pin and another side in contact with the inner surface of the housing.

[0022] A plurality of spoke guide grooves may be formed in an inner surface of the housing, the plurality of spoke guide grooves being recessed to prevent a distal end of each of the plurality of elastic spokes from being disengaged and extending radially about the connecting pin.

[0023] When the internal pressure inside the shell is higher than the external pressure outside the shell and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of deformation of the connecting pin, the connecting pin can be elastically deformed so that the length of the connecting pin is extended and the peripheral part of the cover is spaced apart from the outer surface of the shell.

[0024] When the internal pressure is higher than the external pressure and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of cover deformation, the cover can be elastically deformed so that the peripheral part is separated from the outer surface of the shell, and the critical pressure of connecting pin deformation can be lower than the critical pressure of cover deformation.

[0025] The exhaust hole may be provided as a plurality of exhaust holes, and the plurality of exhaust holes may be arranged such that the exhaust hole having a smaller inner diameter size is located closer to the connecting pin.

[0026] The elastic coefficient of the cover may be higher than the elastic coefficient of the connecting pin and lower than the elastic coefficient of the hook.

[0027] The exhaust device of the present invention elastically deforms in response to an increase in pressure inside the battery pack and allows gas to be released to the outside of the battery pack, and elastically recovers in response to a decrease in pressure inside the battery pack caused by the gas release and prevents external air from entering the battery pack. Thus, a thermal runaway phenomenon in which a fire spreads inside the battery pack due to air entering the battery pack from outside the battery pack is prevented.

[0028] In a venting device according to an embodiment of the present invention (the venting device includes an elastically deformable cover, an elastically deformable hook, and an elastically deformable connecting pin), the range in which the separation distance between the housing and the cover of the battery pack can be elastically restored can be significantly expanded. Therefore, even in the case where the pressure difference between the internal pressure and the external pressure of the battery pack increases sharply, the cover can be opened wide to allow gas to be quickly discharged from the inside of the battery pack to the outside, and when the pressure difference between the internal pressure and the external pressure of the battery pack decreases, the cover can be reliably closed to prevent thermal runaway.

[0029] However, the effects obtainable by the present disclosure are not limited to the above effects, and those skilled in the art will clearly understand other technical effects not mentioned from the following description of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings attached to this specification illustrate some embodiments of the present disclosure and, together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. However, the present disclosure should not be interpreted as being limited to the accompanying drawings:

[0031] Figure 1 is a perspective view of a battery pack according to one embodiment of the present invention;

[0032] Figure 2 is a perspective view of an exhaust device according to a first embodiment of the present invention viewed from the outside, and shows the exhaust device and Figure 1 The state of separation of the walls of the shell;

[0033] Figure 3 is a perspective view of an exhaust device according to a first embodiment of the present invention viewed from the inside, and shows the exhaust device and Figure 1 The state of separation of the walls of the shell;

[0034] Figure 4 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 When the outer peripheral portion of the cover is in close contact with the wall of the shell;

[0035] Figure 5 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The connecting pin is in a state of elastic deformation at the wall of the housing;

[0036] Figure 6 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The wall of the housing is in a state where the connecting pin and the cover are elastically deformed;

[0037] Figure 7 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The wall of the housing is in a state where the connecting pin, the cover and the hook are elastically deformed;

[0038] Figure 8 yes Figure 3 a plan view of the inner surface of a wall of the housing, shown so that the exhaust holes and spoke guide grooves are visible;

[0039] Fig. 9 is a longitudinal sectional view of an exhaust device according to a second embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The outer peripheral portion of the cover is in close contact with the wall of the housing when the cover is in close contact with the wall of the housing; and

[0040] Fig.10 is a longitudinal sectional view of an exhaust device according to a second embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The connecting pin is in a state of elastic deformation at the wall of the shell. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be interpreted as limited to the usual meaning or dictionary meaning, but should be interpreted as meanings and concepts consistent with the technical idea of ​​the present invention based on the principle that the inventor can be his / her own lexicon compiler to appropriately define the concept of the term so as to interpret his / her invention in the best way.

[0042] The embodiments described in this specification and the configurations shown in the drawings are only some of the embodiments of the present invention and do not represent all technical ideas, aspects and features of the present invention. Therefore, it should be understood that when submitting this application, there may be various equivalents and modifications that can replace or modify the embodiments described herein.

[0043] It will be understood that when an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it may be directly on, directly connected to, or coupled to the other element or layer, or there may be one or more intervening elements or layers. When an element or layer is referred to as being "directly on," "directly connected to," or "directly coupled to" another element or layer, there may be no intervening elements or layers. For example, when a first element is described as being "coupled to" or "connected to" a second element, the first element may be directly coupled or connected to the second element, or the first element may be indirectly coupled or connected to the second element via one or more intervening elements.

[0044] In the accompanying drawings, for clarity of illustration, the sizes of various elements, layers, etc. may be exaggerated. The same reference numerals represent the same elements. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. In addition, the use of "may" when describing the embodiments of the present invention relates to "one or more embodiments of the present invention". Statements such as "at least one of ..." and "any one of ...", when following a column of elements, modify the entire column of elements, rather than modifying the individual elements of the list. When phrases such as "at least one of A, B, and C", "at least one of A, B, or C", "at least one selected from the group of A, B, and C", or "at least one selected from A, B, and C" are used to specify the list of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the terms "use", "use ..." and "being used" may be considered to be synonymous with the terms "utilize", "utilize ..." and "being utilized", respectively. As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation, rather than terms of degree, and are intended to account for the inherent variations in measured or calculated values ​​that those of ordinary skill in the art would recognize.

[0045] It will be understood that although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or portions, these elements, components, regions, layers and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or portion from another element, component, region, layer or portion. Therefore, without departing from the teachings of the example embodiments, the first element, component, region, layer or portion discussed below may be referred to as a second element, component, region, layer or portion.

[0046] For ease of description, spatial relational terms (such as "under", "below", "below", "above", "on", etc.) may be used here to describe the relationship of one element or feature to another element or features as shown in the drawings. It will be understood that in addition to the orientations depicted in the drawings, the spatial relational terms are intended to cover different orientations of the device in use or operation. For example, if the device in the drawings is turned over, the elements described as being "under" or "below" other elements or features will be oriented as being "above" or "above" other elements or features. Therefore, the term "under" can cover both above and below orientations. The device can be oriented otherwise (rotated 90 degrees or in other orientations), and the spatial relational descriptors used here should be interpreted accordingly.

[0047] The terms used herein are for the purpose of describing embodiments of the present invention and are not intended to limit the present invention. As used herein, the singular forms "one" and "an" are intended to also include plural forms, unless the context clearly indicates otherwise. It will also be understood that the terms "comprise" and / or "comprising", when used in this specification, specify the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or combinations thereof.

[0048] In addition, any numerical range disclosed and / or quoted herein is intended to include all sub-ranges of the same numerical precision contained in the quoted range. For example, the range of "1.0 to 10.0" is intended to include all sub-ranges between the minimum value 1.0 and the maximum value 10.0 (including these two values), that is, the minimum value is equal to or greater than 1.0, and the maximum value is equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit listed here is intended to include all lower numerical limits contained therein, and any minimum numerical limit listed in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification (including claims) to clearly record any sub-ranges contained in the range clearly recorded here.

[0049] Referring to two compared elements, features, etc. as "the same" may mean that they are "substantially the same." Thus, the phrase "substantially the same" may include situations with deviations that are considered low in the art, such as 5% or less. In addition, when a parameter is referred to as being uniform in a given area, this may mean that it is uniform with respect to an average value.

[0050] Throughout the specification, unless otherwise specified, each element may be in the singular or in the plural.

[0051] When any element is referred to as being disposed (or positioned or placed) "on (or below)" or "on (or below)" a component, this may mean that the arbitrary element is disposed in contact with the upper (or lower) surface of the component, and may also mean that another component may be interposed between the component and any element disposed (or positioned or placed) on (or below) the component.

[0052] Furthermore, it will be understood that when an element is referred to as being "coupled," "linked," or "connected" to another element, the elements may be directly "coupled," "linked," or "connected" to each other, or there may be intervening elements therebetween through which the element may be "coupled," "linked," or "connected" to another element. Furthermore, when a component is referred to as being "electrically coupled" to another component, the component may be directly connected to the other component, or there may be intervening components therebetween such that the component and the other component are indirectly connected to each other.

[0053] Throughout the specification, unless otherwise specified, when "A and / or B" is stated, it means A, B, or A and B. That is, "and / or" includes any or all combinations of the listed multiple items. Unless otherwise specified, when "C to D" is stated, it means C or greater and D or less.

[0054] A battery pack according to one or more embodiments includes at least one battery module and a pack case having an accommodation space in which the at least one battery module is accommodated.

[0055] The battery module may include a plurality of battery cells and a module housing. The battery cells may be housed in a module housing in a stacked form (or stacked arrangement or configuration). Each battery cell may have a positive electrode terminal and a negative electrode terminal, and may be round, prismatic, or pouch-shaped depending on the shape of the battery. In this specification, a battery cell may also be referred to as a secondary battery, a battery, or a cell.

[0056] In a battery pack, a single cell stack may constitute a module instead of a battery module stack. The single cell stack may be accommodated in an accommodation space of a pack case or may be accommodated in an accommodation space partitioned by a frame, a partition wall, or the like.

[0057] The battery cell may generate a large amount of heat during charging / discharging. The generated heat may accumulate in the battery cell, thereby accelerating the degradation of the battery cell. Therefore, the battery pack may further include a cooling member to remove the generated heat, thereby suppressing the degradation of the battery cell. The cooling member may be provided at the bottom of the accommodation space provided with the battery cell, but is not limited thereto, and may be provided at the top or side depending on the battery pack.

[0058] The battery cell can be configured so that the exhaust gas generated inside the battery cell under abnormal operating conditions (also known as thermal runaway or thermal events) is discharged to the outside of the battery cell. The battery pack or battery module can include an exhaust port for exhausting the exhaust gas to prevent or reduce damage to the battery pack or module by the exhaust gas.

[0059] The battery pack may include a battery and a battery management system (BMS) for managing the battery. The battery management system may include a detection device, a balancing device, and a control device. The battery module may include a plurality of cells connected in series and / or in parallel to each other. The battery modules may be connected in series and / or in parallel to each other.

[0060] The detection device may detect the state of the battery (e.g., voltage, current, temperature, etc.) to output state information indicating the state of the battery. The detection device may detect the voltage of each cell constituting the battery or the voltage of each battery module. The detection device may detect the current flowing through the battery module or each battery module constituting the battery pack. The detection device may also detect the temperature of the cell and / or module and / or the ambient temperature at at least one point of the battery.

[0061] The balancing device can perform balancing operations on the battery module and / or the monomers constituting the battery module. The control device can receive status information (such as voltage, current, temperature, etc.) of the battery module from the detection device. The control device can monitor and calculate the status of the battery module (such as voltage, current, temperature, state of charge (SOC), life (health state (SOH)), etc.) based on the status information received from the detection device. In addition, based on the monitored status information, the control device can perform control functions (such as temperature control, balance control, charge / discharge control, etc.) and protection functions (such as over-discharge, over-charge, over-current protection, short circuit, fire extinguishing function, etc.). In addition, the control device can perform wired or wireless communication functions with external devices of the battery pack (such as higher-level controllers or vehicles, chargers, power conversion systems, etc.).

[0062] The control device can control the charging / discharging operation and the protection operation of the battery. To this end, the control device can include a charging / discharging control unit, a balancing control unit and / or a protection unit.

[0063] A battery management system is a system that monitors the battery status and performs diagnostic and control, communication, and protection functions, and can calculate the charge / discharge status, calculate the battery life or state of health (SOH), cut off the battery power when necessary (e.g., relay control), control thermal management (e.g., cooling, heating, etc.), perform high-voltage interlock functions, and / or can detect and / or calculate insulation and short circuit conditions.

[0064] A relay may be a mechanical contactor that opens and closes by the magnetic force of a coil or a semiconductor switch such as a metal oxide semiconductor field effect transistor (MOSFET).

[0065] The relay control has the function of cutting off the power supply to the battery in the event of a problem in the vehicle and battery system (or when a problem occurs in the vehicle and battery system), and may include one or more relays and a pre-charge relay at the positive terminal and the negative terminal, respectively.

[0066] In pre-charge control, when the battery load is connected, there is a risk of inrush current occurring in the high voltage capacitor on the input side of the inverter. Therefore, in order to prevent inrush current when starting the vehicle, the pre-charge relay may be operated before the main relay is connected, and a pre-charge resistor may be connected.

[0067] The high voltage interlock is a circuit that uses a small signal to detect whether all high voltage parts of the entire vehicle system are connected, and can have the function of forcibly disconnecting the relay if (or when) a disconnection occurs in even one position on the entire circuit.

[0068] Figure 1 is a perspective view of a battery pack according to one embodiment of the present invention, Figure 2 is a perspective view of an exhaust device according to a first embodiment of the present invention viewed from the outside and shows a configuration in which the exhaust device is connected to Figure 1 The state of separation of the walls of the shell, Figure 3 is a perspective view of an exhaust device according to a first embodiment of the present invention viewed from the inside and showing a configuration in which the exhaust device is connected to the exhaust device. Figure 1 The state of separation of the walls of the shell, Figure 4 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 When the outer peripheral portion of the cover is in close contact with the wall of the housing, Figure 5 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The connecting pin is in the state of elastic deformation at the wall of the shell. Figure 6 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The wall of the housing is in a state where the connecting pin and the cover are elastically deformed. Figure 7 is a longitudinal sectional view of an exhaust device according to a first embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The wall of the housing is in a state where the connecting pin, cover and hook are elastically deformed. Figure 8 yes Figure 3 A plan view of the inner surface of a wall of the housing (which is shown so that the exhaust holes and spoke guide grooves are visible).

[0069] Reference Figures 1 to 8, a battery pack 1 according to one embodiment of the present invention includes a housing 10, a plurality of battery modules 2, and an exhaust device 100. The housing 10 may include a plurality of walls 12 configured to define an internal space. Figure 1 The housing 10 shown has a substantially cuboid shape and includes six walls, each wall having a rectangular shape in plan view. Figure 1 The shape of the housing 10 shown in FIG. 1 is merely illustrative, and the housing may also be provided in a different shape.

[0070] The plurality of battery modules 2 are accommodated in the inner space of the housing 10. Each battery module 2 includes a plurality of battery cells 5 capable of charge and discharge. The exhaust device 100 is an exhaust device according to the first embodiment of the present invention and is installed at one of the plurality of walls 12 of the housing 10.

[0071] A connection pin through hole 20 and a plurality of exhaust holes (25 and 30) are formed in one of the plurality of walls 12 to pass through the wall 12. The connection pin 140 of the exhaust device 100 may pass through the wall 12 through the connection pin through hole 20. Therefore, the exhaust device 100 may be installed at the wall 12 of the housing 10.

[0072] The plurality of exhaust holes (25 and 30) may be formed around the connection pin through hole 20. The plurality of exhaust holes (25 and 30) may include a plurality of first exhaust holes 25 and a plurality of second exhaust holes 30 having an inner diameter VD2 smaller than an inner diameter VD1 of the first exhaust holes 25.

[0073] The size of the inner diameter VD1 of the first exhaust hole 25 may be, for example, 2 mm, and the size of the inner diameter VD2 of the second exhaust hole 30 may be, for example, 1 mm. The second exhaust hole 30 may be located closer to the connecting pin through hole 20 than the first exhaust hole 25. In other words, the second exhaust hole 30 may be located closer to the connecting pin 140 passing through the connecting pin through hole 20 than the first exhaust hole 25.

[0074] The plurality of first exhaust holes 25 may be arranged at equal angular intervals while being spaced apart by the same distance from the connecting pin through hole 20. The plurality of second exhaust holes 30 may be arranged at equal angular intervals while being spaced apart by the same distance from the connecting pin through hole 20. Therefore, the sum of the cross-sectional areas of the plurality of exhaust holes (25 and 30) may be further increased in a circular region within a predetermined radius from the axis PX passing through the center of the connecting pin through hole 20 and parallel to the normal of the wall 12. Therefore, the release of gas from the inside of the housing 10 to the outside may be further promoted.

[0075] In addition, since gas and particles can be discharged to the outside of the case 10 through the first exhaust hole 25 even when the second exhaust hole 30 is blocked due to particles having a relatively large size, serious accidents such as explosion of the battery pack 1 caused by blockage of gas release can be prevented.

[0076] in addition, Figure 2 , Figure 3 and Figure 8 The shapes, arrangements and numbers of the plurality of vent holes (25 and 30) shown in the figure are merely illustrative, and the present invention is not limited thereto. For example, vent holes of three or more different inner diameter sizes may be formed as a plurality of vent holes in the wall, and the plurality of vent holes may be arranged such that the vent holes with smaller inner diameter sizes are positioned closer to the connecting pin.

[0077] The exhaust device 100 includes a cover 101, a hook 120, and a connecting pin 140. The cover 101 is positioned to cover the plurality of exhaust holes (25 and 30) from the outside of the housing 10. Specifically, the cover 101 is located on one side of the wall 12, and by covering the plurality of exhaust holes (25 and 30) with the cover 101, the plurality of exhaust holes (25 and 30) are covered so as not to be visible from the outside of the housing 10.

[0078] The connecting pin 140 passes through the wall 12 of the housing 10 through the connecting pin through hole 20. The connecting pin 140 extends in the thickness direction of the wall 12. One side of the connecting pin 140 is connected to the cover 101, and the other side of the connecting pin 140 is connected to the hook 120. The hook 120 is connected to the other side of the connecting pin 140 and is located in the housing 10 so that the cover 101 and the connecting pin 140 are supported by the wall 12 of the housing 10.

[0079] The cover 101 may include a central portion 102 and a peripheral portion 105. The central portion 102 is coupled to the connecting pin 140. The peripheral portion 105 may radially expand from the central portion 102 about the axis PX. An end 108 of the peripheral portion 105 may be in close contact with the outer surface 13 of the wall 12 of the housing 10 to prevent gas from moving through the plurality of exhaust holes (25 and 30).

[0080] The central portion 102 and the peripheral portion 105 may be connected without a clear boundary. The end 108 of the peripheral portion 105 may extend along a circular trajectory around the axis PX. The cover 101 may be a plate-like member having a circular shape in a plan view, and wherein the central portion 102 protrudes more toward the outside of the housing 10 than the peripheral portion 105.

[0081] The cover 101 is elastically deformable. When the pressure PI inside the housing 10 in which the plurality of battery cells 5 are disposed (hereinafter referred to as “internal pressure”) is higher than the pressure PO outside the housing 10 (hereinafter referred to as “external pressure”) and the pressure difference between the internal pressure PI and the external pressure PO is higher than the cover deformation critical pressure PCC, as Figure 6 As shown, the cover 101 can be elastically deformed so that the end 108 of the peripheral portion 105 is spaced apart from the outer surface 13 of the wall 12 of the housing 10 .

[0082] When the pressure difference between the internal pressure PI and the external pressure PO decreases and becomes lower than or equal to the cover deformation critical pressure PCC, the cover 101 may be restored to the state due to the elastic restoring force. Figure 5 Shown in its original shape.

[0083] The external pressure PO is the pressure on one side of the wall 12 and thus may be referred to as “one side pressure”. The internal pressure PI is the pressure on the other side of the wall 12 and thus may be referred to as “other side pressure”. The cover 101 may be formed of a metal material such as spring steel.

[0084] The connection pin 140 may include a cover coupling portion 141, a hook coupling portion 145, and a middle deformation portion 150. The cover coupling portion 141, the hook coupling portion 145, and the middle deformation portion 150 may be disposed along the axis PX.

[0085] The cover coupling portion 141 may be coupled to the central portion 102 of the cover 101. The hook coupling portion 145 may be coupled to the elastic spoke 121 of the hook 120. The middle deformation portion 150 may be located between the cover coupling portion 141 and the hook coupling portion 145. One side of the middle deformation portion 150 may be coupled to the cover coupling portion 141, and the other side of the middle deformation portion 150 may be coupled to the hook coupling portion 145.

[0086] The middle deformation portion 150 may include a plurality of bent leads 152. The plurality of leads 152 may be elastically deformed in a non-bending direction when subjected to a force in the direction in which both ends in the longitudinal direction are stretched, and may be restored to its original bent shape when the force is removed. One side end of the plurality of leads 152 may be joined to the cover coupling portion 141, and the other side end of the plurality of leads 152 may be joined to the hook coupling portion 145 by a method such as welding.

[0087] The connecting pin 140 is elastically deformable. When the internal pressure PI is higher than the external pressure PO and the pressure difference between the internal pressure PI and the external pressure PO is higher than the connecting pin deformation critical pressure PCP, as shown in FIG. Figure 5As shown, the length of the connection pin 140 may be extended, and the end 108 of the peripheral portion 105 may be spaced apart from the outer surface 13 of the wall 12 of the housing 10. Specifically, the plurality of lead wires 152 may be elastically deformed from a bent shape to an unbent shape.

[0088] When the pressure difference between the internal pressure PI and the external pressure PO decreases and becomes lower than or equal to the connecting pin deformation critical pressure PCP, the connecting pin 140 may be restored to Figure 4 That is, the plurality of leads 152 may be restored to their original shape as shown. The connection pin 140 may be formed of a metal material such as spring steel.

[0089] The hook 120 may include a plurality of elastic spokes 121. The plurality of elastic spokes 121 may extend radially about the axis PX and may be disposed at equal angular intervals about the axis PX.

[0090] One side end 123 of the elastic spoke 121 relatively close to the axis PX is connected to the hook connecting portion 145 of the connecting pin 140, and the other side end 125 of the elastic spoke 121 contacts the inner surface 14 of the wall 12 of the shell 10, and the other side end 125 is positioned farther away from the axis PX than the one side end 123.

[0091] When the internal pressure PI is higher than the external pressure PO and the pressure difference between the internal pressure PI and the external pressure PO is higher than the hook deformation critical pressure PCH, as Figure 7 As shown, the hook 120 can be elastically deformed so that the connecting pin 140 moves to the outside of the housing 10 (ie, the one side of the wall 12 ) and the end 108 of the peripheral portion 105 of the cover 101 is spaced apart from the outer surface 13 of the housing 10 .

[0092] Specifically, Figure 7 As shown, the plurality of elastic spokes 121 are opened relative to the connecting pin 140 , so that the angle between the axis PX and the elastic spokes 121 increases, and thus the connecting pin 140 moves to the outside of the housing 10 .

[0093] When the pressure difference between the internal pressure PI and the external pressure PO decreases and becomes lower than or equal to the hook deformation critical pressure PCH, the hook 120 may elastically recover to Figure 6 That is, the plurality of elastic spokes 121 may be closed relative to the connecting pin 140 so that the angle between the axis PX and the elastic spokes 121 is reduced, and thus the connecting pin 140 may move toward the inside of the housing 10 and move to its original position. The hook 120 may be formed of a metal material such as spring steel.

[0094] A plurality of spoke guide grooves 35 may be formed in the inner surface 14 of the wall 12 of the housing 10, which are recessed to prevent the tip of the other side end 125 of each of the plurality of elastic spokes 121 from being disengaged. The plurality of spoke guide grooves 35 may extend radially about the connecting pin 140.

[0095] The spoke guide grooves 35 may extend radially about the axis PX and may be disposed at equal angular intervals about the axis PX. The number of elastic spokes 121 and the number of spoke guide grooves 35 may be the same so that the elastic spokes 121 correspond to the spoke guide grooves 35 one by one.

[0096] Due to the plurality of spoke guide grooves 35 , when the plurality of elastic spokes 121 are elastically deformed in an opening or closing direction relative to the connecting pin 140 , the distal end 125 of each of the plurality of elastic spokes 121 may smoothly move radially about the axis PX.

[0097] In the absence of the multiple spoke guide grooves 35, when the multiple elastic spokes 121 are opened relative to the connecting pin 140 due to the pressure difference between the internal pressure PI and the external pressure PO, or when the multiple elastic spokes 121 elastically recover in the closing direction relative to the connecting pin 140 due to the reduction of the pressure difference between the internal pressure PI and the external pressure PO, the degree of opening or closing may be different for each of the multiple elastic spokes 121, and the connecting pin 140 may be tilted within the connecting pin through hole 20.

[0098] When the connecting pin 140 is tilted in the connecting pin through hole 20, even when the pressure difference between the internal pressure PI and the external pressure PO is not large, a portion of the end 108 of the peripheral portion 105 of the cover 101 may be spaced apart from the outer surface 13 of the shell 10, and the internal space of the shell 10 cannot be sealed.

[0099] One side end 37 of each spoke guide groove 35 close to the axis PX may be connected to the inner side surface of the connecting pin through hole 20. The other side end 38 of each spoke guide groove 35 farther from the axis PX than the one side end 37 may not be connected to the first exhaust hole 25. Figure 3 and Figure 8 The shape of the spoke guide groove 35 shown in FIG. 1 is merely illustrative and does not correspond to the shape of the spoke guide groove 35 shown in FIG. Figure 3 and Figure 8 Different from the above, one side end portion of each spoke guide groove may not be connected to the inner side surface of the connecting pin through hole 20 , and the other side end portion of each spoke guide groove may be connected to the first exhaust hole 25 .

[0100] The exhaust device 100 can be easily installed at the wall 12 by pushing the hook 120 into the connecting pin through hole 20 from the outside of the housing 10. When the hook 120 is inserted into the connecting pin through hole 20, the plurality of elastic spokes 121 are closed so that the end 125 of each of the plurality of elastic spokes 121 becomes closer to the connecting pin 140, and thus the hook 120 passes through the connecting pin through hole 20.

[0101] When the plurality of elastic spokes 121 deviate from the connection pin through hole 20, the plurality of elastic spokes 121 open so that the end 125 of each of the plurality of elastic spokes 121 becomes away from the connection pin 140, and thus the hook 120 cannot pass through the connection pin through hole 20. As a result, the exhaust device 100 can be supported so as not to be separated from the housing 10.

[0102] In the exhaust device 100 according to the first embodiment of the present invention, the connection pin deformation critical pressure PCP of the connection pin 140 may be lower than the cover deformation critical pressure PCC of the cover 101, and the hook deformation critical pressure PCH of the hook 120 may be higher than the cover deformation critical pressure PCC of the cover 101. In terms of elastic coefficient, the elastic coefficient of the cover 101 may be higher than the elastic coefficient of the connection pin 140 and lower than the elastic coefficient of the hook 120.

[0103] With such a configuration, when, for example, an accident occurs in which flammable substances and gas are released from the battery cell 5 to the inside of the housing 10 and the pressure difference between the internal pressure PI and the external pressure PO becomes higher than the connecting pin deformation critical pressure PCP, as shown in FIG. Figure 5 As shown, the length of the connecting pin 140 can be extended so that the connecting pin 140 can be elastically restored, and the cover 101 and the hook 120 can not be elastically deformed. Therefore, the end 108 of the peripheral portion 105 of the cover 101 can be spaced apart from the outer surface 13 of the housing 10 by a first distance G1, and gas and foreign matter can be discharged from the inside of the housing 10 to the outside.

[0104] When the pressure difference between the internal pressure PI and the external pressure PO becomes higher than the cap deformation critical pressure PCC and the connecting pin deformation critical pressure PCP, as shown in FIG. Figure 6 As shown, the length of the connecting pin 140 can be extended so that the connecting pin 140 can be elastically restored, and the cover 101 can also be deformed to be elastically restored, but the hook 120 may not be elastically deformed. Figure 5 Compared with the case where the cover 101 has a peripheral portion 105, the end 108 of the cover 101 can be spaced apart from the outer surface 13 of the shell 10 by a second distance G2 greater than the first distance G1, and gas and foreign matter can be discharged from the inside of the shell 10 to the outside at a higher flow rate.

[0105] When the pressure difference between the internal pressure PI and the external pressure PO becomes higher than the hook deformation critical pressure PCH and the connecting pin deformation critical pressure PCP and the cover deformation critical pressure PCC, as shown in FIG. Figure 7 As shown, the length of the connecting pin 140 can be extended so that the connecting pin 140 can be elastically restored, the cover 101 can also be deformed to be elastically restored, and the hook 120 can also be deformed to be elastically restored. Figure 6 Compared with the case where the end 108 of the peripheral portion 105 of the cover 101 can be spaced apart from the outer surface 13 of the shell 10 by a third distance G3 greater than the second distance G2, and gas and foreign matter can be discharged from the inside of the shell 10 to the outside at a higher flow rate.

[0106] The distance (hereinafter referred to as "separation distance") separating the outer surface 13 of the housing 10 from the end 108 of the peripheral portion 105 of the cover 101 may increase as the pressure difference (hereinafter referred to as "pressure difference") between the internal pressure PI and the external pressure PO increases. Specifically, when the pressure difference increases in the interval between the connecting pin deformation critical pressure PCP and the cover deformation critical pressure PCC, the separation distance may increase slightly, but when the pressure difference exceeds the cover deformation critical pressure PCC, the separation distance may increase significantly.

[0107] Furthermore, when the pressure difference increases within the interval between the cap deformation critical pressure PCC and the hook deformation critical pressure PCH, the separation distance may increase slightly, but when the pressure difference exceeds the hook deformation critical pressure PCH, the separation distance may increase significantly again.

[0108] In addition, when the pressure difference between the internal pressure PI and the external pressure PO becomes lower than or equal to the connecting pin deformation critical pressure PCP due to the gas released from the inside to the outside of the housing 10, the hook 120, the cover 101 and the connecting pin 140 are elastically restored, and as shown in FIG. Figure 4 As shown, the end 108 of the peripheral portion 105 of the cover 101 is again in close contact with the outer surface 13 of the housing 10. Therefore, the air outside the housing 10 cannot enter the housing 10 through the plurality of exhaust holes (25 and 30).

[0109] Fig. 9 is a longitudinal sectional view of an exhaust device according to a second embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 When the outer peripheral portion of the cover is in close contact with the wall of the housing, Fig.10 is a longitudinal sectional view of an exhaust device according to a second embodiment of the present invention and shows that when the exhaust device is installed in Figure 1 The connecting pin is in a state of elastic deformation at the wall of the shell.

[0110] Reference Fig. 9 and Fig.10 , the exhaust device 200 according to the second embodiment of the present invention includes a cover 101, a hook 120 and a connecting pin 240. Here, the cover 101 and the hook 120 are the same as those in the above reference Figures 1 to 8 The cover 101 and the hook 120 included in the exhaust device 100 according to the first embodiment of the present invention are described to be the same and are denoted by the same reference numerals. Therefore, repeated description thereof will be omitted.

[0111] The connection pin 240 may include a cover coupling portion 241, a hook coupling portion 245, and a middle deformation portion 250. The cover coupling portion 241, the hook coupling portion 245, and the middle deformation portion 250 may be disposed along the axis PX.

[0112] The cover coupling portion 241 may be coupled to the central portion 102 of the cover 101. The hook coupling portion 245 may be coupled to the elastic spoke 121 of the hook 120. The middle deformation portion 250 may be located between the cover coupling portion 241 and the hook coupling portion 245. One side of the middle deformation portion 250 may be coupled to the cover coupling portion 241, and the other side of the middle deformation portion 250 may be coupled to the hook coupling portion 245.

[0113] The middle deformation part 250 may include a coil spring 252. The coil spring 252 may extend along the axis PX when subjected to a force in a direction in which both ends of the axis PX are pulled, and may elastically return to its original contracted shape when the force is removed. One end of the coil spring 252 may be coupled to the cover coupling part 241, and the other end of the coil spring 252 may be coupled to the hook coupling part 245 by a method such as welding.

[0114] The connecting pin 240 is elastically deformable. When the internal pressure PI is higher than the external pressure PO and the pressure difference between the internal pressure PI and the external pressure PO is higher than the connecting pin deformation critical pressure PCP, as shown in FIG. Fig.10 As shown, the length of the connecting pin 240 may extend and the end 108 of the peripheral portion 105 may be spaced apart from the outer surface 13 of the wall 12 of the housing 10. Specifically, the coil spring 252 may be elastically deformed in a direction in which the length of the coil spring 252 increases along the axis PX.

[0115] When the pressure difference between the internal pressure PI and the external pressure PO decreases and becomes lower than or equal to the connecting pin deformation critical pressure PCP, the connecting pin 240 may be restored to Fig. 9 That is, the coil spring 252 can be restored in a direction in which the length of the coil spring 252 decreases along the axis PX. The connecting pin 240 can be formed of a metal material such as spring steel.

[0116] The above-mentioned exhaust devices 100 and 200 elastically deform in response to an increase in the pressure inside the battery pack 1 (that is, the internal pressure of the housing 10) and allow the gas to be released to the outside of the battery pack 1, and elastically recover in response to a decrease in the pressure inside the battery pack 1 caused by the gas release and prevent the outside air from entering the battery pack 1. Therefore, a thermal runaway phenomenon in which a fire inside the battery pack 1 spreads due to the air entering the battery pack 1 from the outside of the battery pack 1 is prevented.

[0117] In the exhaust devices 100 and 200, the range in which elastic recovery can be performed can be significantly expanded for the separation distance between the housing 10 and the cover 101 of the battery pack 1. Therefore, even in the case where the pressure difference between the internal pressure and the external pressure of the battery pack 1 increases sharply, the cover 101 can be opened wide to allow gas to be quickly discharged from the inside of the battery pack 1 to the outside, and when the pressure difference between the internal pressure and the external pressure of the battery pack 1 decreases, the cover 101 can be reliably closed to prevent the thermal runaway phenomenon.

[0118] In addition, it has been described above that in the exhaust devices 100 and 200 according to the first and second embodiments of the present invention, the connecting pin deformation critical pressure PCP is lower than the cover deformation critical pressure PCC, and the hook deformation critical pressure PCH is higher than the cover deformation critical pressure PCC, but such a relationship is only illustrative. For example, the elastic coefficients of the cover, the hook, and the connecting pin may be set so that the cover deformation critical pressure is higher than the hook deformation critical pressure, and the hook deformation critical pressure is higher than the connecting pin deformation critical pressure.

[0119] The exhaust device of the present invention elastically deforms in response to an increase in pressure inside the battery pack and allows gas to be released to the outside of the battery pack, and elastically recovers in response to a decrease in pressure inside the battery pack caused by the gas release and prevents external air from entering the battery pack. Therefore, a thermal runaway phenomenon in which a fire inside the battery pack spreads due to air entering the battery pack from outside the battery pack is prevented.

[0120] In the exhaust device according to an embodiment of the present invention (the exhaust device includes an elastically deformable cover, an elastically deformable hook, and an elastically deformable connecting pin), the range in which elastic recovery can be achieved for the separation distance between the housing and the cover of the battery pack can be significantly expanded. Therefore, even in the case where the pressure difference between the internal pressure and the external pressure of the battery pack increases sharply, the cover can be opened wide to allow gas to be quickly discharged from the inside of the battery pack to the outside, and when the pressure difference between the internal pressure and the external pressure of the battery pack decreases, the cover can be reliably closed to prevent thermal runaway.

[0121] However, the effects obtainable by the present disclosure are not limited to the above effects, and other technical effects not mentioned will be clearly understood by those skilled in the art from the following description of the present disclosure.

[0122] Although the present invention has been described with reference to the embodiments and the accompanying drawings showing aspects of the present invention, the present invention is not limited thereto. Various modifications and changes can be made by those skilled in the art within the scope of the technical idea of ​​the present invention.

Claims

1. An exhaust device, comprising: a cover located on one side of the wall in which a vent hole is formed to cover the vent hole through which gas can move; a connecting pin configured to pass through the wall and having one side connected to the cover; and A hook is located at the other side of the wall and connected to the other side of the connecting pin so that the cover and the connecting pin are supported by the wall.

2. The exhaust device according to claim 1, wherein the cover comprises: a central portion coupled to the connecting pin; and The peripheral portion is configured to radially expand from the central portion and to closely contact with one side surface of the wall to block the gas from moving through the exhaust hole.

3. The exhaust device according to claim 2, wherein: When the other side pressure of the other side of the wall is higher than the one side pressure of the one side of the wall and the pressure difference between the other side pressure and the one side pressure is greater than the critical pressure of cover deformation, the cover elastically deforms so that the peripheral portion is spaced apart from the one side surface of the wall.

4. The exhaust device according to claim 2, wherein: When the pressure on the other side of the other side of the wall is higher than the pressure on the one side of the wall and the pressure difference between the pressure on the other side and the pressure on the one side is greater than the critical pressure for hook deformation, the hook elastically deforms so that the connecting pin moves to the one side of the wall and the peripheral portion of the cover is spaced apart from the one side surface of the wall.

5. The exhaust device according to claim 2, wherein: When the pressure on the other side of the other side of the wall is higher than the pressure on the one side of the wall and the pressure difference between the pressure on the other side and the pressure on the one side is greater than the critical pressure for deformation of the connecting pin, the connecting pin elastically deforms so that the length of the connecting pin is extended and the peripheral portion of the cover is spaced apart from the one side surface of the wall.

6. The exhaust device according to claim 5, wherein the connecting pin comprises: a cover coupling portion coupled to the cover; a hook coupling portion coupled to the hook; as well as A middle deformation portion is located between the cover coupling portion and the hook coupling portion and has one side coupled to the cover coupling portion and the other side coupled to the hook coupling portion. 7 . The exhaust device according to claim 6 , wherein the intermediate deformation portion includes a plurality of lead wires bent to be elastically deformable in a non-bent direction.

8. The exhaust device of claim 6, wherein the intermediate deformation portion comprises a coil spring.

9. A battery pack comprising: a housing configured to define an interior space and having a vent formed therein through which gas can move; at least one battery cell accommodated in the internal space; as well as An exhaust device includes: a cover positioned to cover the exhaust hole from the outside of the shell; a connecting pin configured to pass through the shell and have one side connected to the cover; and a hook located on the inside of the shell and connected to the other side of the connecting pin so that the cover and the connecting pin are supported by the shell.

10. The battery pack of claim 9, wherein the cover comprises: a central portion coupled to the connecting pin; and The peripheral portion is configured to radially expand from the central portion and to closely contact with the outer surface of the housing to block the gas from moving through the exhaust hole.

11. The battery pack according to claim 10, wherein: When the internal pressure on the inner side of the shell is higher than the external pressure on the outer side of the shell and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of cover deformation, the cover elastically deforms so that the peripheral part is spaced apart from the outer surface of the shell. 12 . The battery pack according to claim 11 , wherein a separation distance between the outer surface and the outer peripheral portion increases as the pressure difference between the internal pressure and the external pressure increases.

13. The battery pack according to claim 10, wherein: When the internal pressure on the inner side of the shell is higher than the external pressure on the outer side of the shell and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of hook deformation, the hook elastically deforms so that the connecting pin moves to the outer side of the shell and the peripheral portion of the cover is spaced apart from the outer surface of the shell.

14. The battery pack according to claim 13, wherein: In a case where the internal pressure is higher than the external pressure and the pressure difference between the internal pressure and the external pressure is greater than the cover deformation critical pressure, the cover is elastically deformed so that the peripheral portion is spaced apart from the outer surface of the housing; as well as The hook deformation critical pressure is higher than the cover deformation critical pressure. 15 . The battery pack according to claim 13 , wherein the hook comprises a plurality of elastic spokes, each of the elastic spokes having one side coupled to the connecting pin and another side in contact with an inner surface of the case. 16 . The battery pack according to claim 15 , wherein a plurality of spoke guide grooves are formed in the inner surface of the case, the plurality of spoke guide grooves being recessed to prevent a distal end of each of the plurality of elastic spokes from being disengaged and extending radially about the connecting pin.

17. The battery pack according to claim 10, wherein: When the internal pressure on the inner side of the shell is higher than the external pressure on the outer side of the shell and the pressure difference between the internal pressure and the external pressure is greater than the critical pressure of deformation of the connecting pin, the connecting pin elastically deforms so that the length of the connecting pin is extended and the peripheral portion of the cover is spaced apart from the outer surface of the shell.

18. The battery pack according to claim 17, wherein: In a case where the internal pressure is higher than the external pressure and the pressure difference between the internal pressure and the external pressure is greater than the cover deformation critical pressure, the cover is elastically deformed so that the peripheral portion is spaced apart from the outer surface of the housing; as well as The critical deformation pressure of the connecting pin is lower than the critical deformation pressure of the cover.

19. The battery pack according to claim 9, wherein: The exhaust hole is provided as a plurality of exhaust holes; and The plurality of exhaust holes are arranged such that an exhaust hole having a smaller inner diameter size is located closer to the connecting pin. 20 . The battery pack according to claim 9 , wherein an elastic coefficient of the cover is higher than an elastic coefficient of the connecting pin and lower than an elastic coefficient of the hook.

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