Battery system and vehicle including the same

Abstract

Disclosed are a battery system and a vehicle including the same, the battery system including: a battery module; a pack case in which the battery modules are mounted; and an elastic part that is installed between the pack case and the battery module, presses the battery module against the pack case, and an end portion of the elastic part is supported by the pack case or the battery module through a cap made of a refractory material.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a battery system having improved safety in an abnormal battery situation and a vehicle including the same. BACKGROUND

[0002] Recently, technologies for reducing carbon have been actively developed to address environmental problems such as abnormal atmospheric temperatures. In order to reduce carbon, energy needs to be generated through an eco-friendly method rather than fossil fuels, the generated energy needs to be stored in the form of electric energy, and the stored electric energy needs to be used for vehicles, various types of industrial sites, and homes.

[0003] In order to utilize electric energy while reducing carbon, a battery capable of storing and releasing electric energy must be used. Therefore, it is necessary to secure the performance of the battery to sufficiently store electric energy and use electric energy without any inconvenience.

[0004] A battery mainly uses a redox reaction of metal ions. The battery uses high-density metal ions to improve the capacity, charging and discharging performance, and efficiency of the battery. Many studies have also been conducted on materials constituting an electrolyte and a solid electrolyte, etc. However, there is a general problem that as the performance of the battery develops, the stability of the battery decreases.

[0005] A battery used in a vehicle, industry, or home is manufactured in a physical unit called a battery pack. The battery pack is configured so that a plurality of battery cells are embedded in a battery case and are sealed. The battery pack is used to prevent a fire from spreading to the outside even in the case of an accident such as thermal runaway occurring in the battery, and to protect the battery cells therein so that the battery cells are not deteriorated due to being affected by the outside environment, or the battery cells are not physically damaged.

[0006] In the battery pack, a plurality of battery cells are embedded in the form of an intermediate module. A battery module is configured by assembling a plurality of battery cells into one module. A plurality of modules are fastened into a battery pack case so that the battery pack is completely manufactured. When the battery is maintained, the unit of the module can be maintained, thereby facilitating maintenance.

[0007] A plurality of unit battery cells constituting the battery module include a positive electrode, a negative electrode, and an electrolyte. Since the battery cell generates heat when charged and discharged, it is necessary to effectively dissipate heat from the battery cell. In addition, the battery module, or the battery pack, needs to be designed to effectively dissipate heat to prevent a safety accident.

[0008] Meanwhile, when a battery suffers from a manufacturing error, when a battery is overcharged or discharged, or when a battery ages, the battery can deteriorate. Furthermore, when a battery continues to deteriorate, a fire can eventually occur. Thus, there is a need to prepare in advance to prevent a fire from occurring in a battery. To this end, it is important to always sense the state of a battery and to identify and address a problem in advance when a problem occurs. In the case of an unexpected problem, damage must be minimized.

[0009] In particular, when a flame is generated in a specific cell of a specific module among a plurality of battery modules in a battery pack, there is a need to prevent the flame from spreading to another adjacent battery cell, and there is also a need to prevent the flame from spreading to another adjacent module. Thus, in view of a battery module, gas in a battery cell having a problem needs to be smoothly discharged, and the influence of the discharged gas and flame on another cell or another module can be maximally prevented or delayed.

[0010] The above explained as background art is only to help understanding the background art of the present disclosure, and does not mean that the present disclosure falls within the scope of the related art known to those skilled in the art. SUMMARY

[0011] TECHNICAL PROBLEM

[0012] The present disclosure aims to solve the above problems, and an object of the present disclosure is to provide a battery system and a vehicle including the same, in which, in the case where a fire occurs in a specific battery cell or a battery module, the fire is prevented from spreading to an adjacent battery cell or an adjacent module, and gas is smoothly discharged, so that battery safety can be improved.

[0013] The technical problems to be solved by the present disclosure are not limited to the above-mentioned technical problems, and other technical problems not mentioned above can be clearly understood by those skilled in the art of the present disclosure according to the following description.

[0014] TECHNICAL SOLUTION

[0015] To achieve the above object, the present disclosure provides a battery system including a battery module, a battery pack case in which the battery module is installed, and an elastic portion installed between the battery pack case and the battery module and configured to press the battery module based on the battery pack case, the elastic portion having an end portion supported on the battery pack case or the battery module by means of a cap made of a fire-resistant material.

[0016] In the case of the battery system according to the present disclosure, an exhaust portion can be formed on an outer surface of the battery module facing the battery pack case, and the elastic portion can be disposed at a position avoiding the exhaust portion.

[0017] In the case of the battery system according to the disclosure, the elastic part can include a first cap, a second cap, and an elastic body, and the elastic body can be located between the first cap and the second cap.

[0018] In the case of the battery system according to the disclosure, the first cap of the elastic part can be closely attached to an inner surface of the battery pack case, and the second cap of the elastic part can be closely attached to an outer surface of the battery module.

[0019] In the case of the battery system according to the disclosure, the first cap or the second cap of the elastic part can be attached to the inner surface of the battery pack case or the outer surface of the battery module by an adhesive, and the adhesive can be made of a heat-resistant material.

[0020] In the case of the battery system according to the disclosure, the first cap of the elastic part can be inserted into and fixed to the second cap so that the elastic body remains compressed between the first cap and the second cap.

[0021] In the case of the battery system according to the disclosure, the first cap of the elastic part can be extracted from the second cap by gas or flame generated in the battery module, and the elastic body can be stretched by extraction of the first cap.

[0022] In the case of the battery system according to the disclosure, the first cap of the elastic part can be extracted from the second cap by an increase in the internal temperature of the battery pack case, and the elastic body can be stretched by extraction of the first cap.

[0023] In the case of the battery system according to the disclosure, the first cap of the elastic part can be caught and fixed in a state of being inserted into the second cap, and the first cap and the second cap are separated when the second cap expands due to high temperature.

[0024] In the case of the battery system according to the disclosure, the first cap of the elastic part can be bonded and fixed in a state of being inserted into the second cap, and the first cap can be separated from the second cap when the bonding force is removed by high temperature.

[0025] In the case of the battery system according to the disclosure, the elastic part can be provided as a plurality of elastic parts located between the battery pack case and the battery module, and the elastic force of the elastic part increases as the distance from the center of the battery pack case decreases.

[0026] In the case of the battery system according to the disclosure, the elastic part close to the center of the battery pack case can have a higher elastic modulus or a greater compression amount than the elastic part spaced apart from the center of the battery pack case.

[0027] In the case of the battery system according to the disclosure, the module cover can be coupled to the battery module and cover one side of the battery module, and the elastic portion is disposed between the battery pack case and the module cover.

[0028] In the case of the battery system according to the disclosure, the elastic portion can be disposed at a point between the battery pack case and the module cover and fixed to the module cover.

[0029] In the case of the battery system according to the disclosure, one end of the elastic portion can be fixed to the module cover, and the other end of the elastic portion can be spaced apart from the battery pack case.

[0030] In the case of the battery system according to the disclosure, the elastic portion can be stretched due to gas or flame or high temperature in the battery pack case, and both opposite ends of the elastic portion can be supported on the battery pack case and the module cover, respectively, when the elastic portion is stretched.

[0031] In the case of the battery system according to the disclosure, the battery pack case can include a case main body that is open at one side thereof, and a battery pack cover configured to close the case main body, and the elastic portion can be located between the battery pack cover and the battery module.

[0032] In the case of the battery system according to the disclosure, when gas or flame or high temperature occurs inside the battery pack case, the spacing between the battery pack cover and the battery module can increase due to expansion of the battery pack cover, the elastic portion can be stretched to the extent that the spacing between the battery pack cover and the battery module increases, and the elastic portion can press the battery module based on the battery pack cover.

[0033] A vehicle according to the disclosure includes the above-described battery system.

[0034] Advantageous Effects

[0035] The battery system according to the disclosure and the vehicle including the same can prevent the spread of fire to another adjacent cell or module in the case of a fire occurring in a certain battery cell or battery module, and gas can be smoothly discharged from the battery cell or battery module having a problem, thereby improving the overall safety of the battery system and an advanced system using the same.

[0036] Effects obtained by the disclosure are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a view illustrating a battery system according to an embodiment of the disclosure.

[0038] Figure 2 is a view illustrating Figure 1 a resilient portion of the battery system illustrated.

[0039] Figure 3 is a cross-sectional view illustrating a case where the resilient portion is disposed at an upper side of the battery system of the disclosure.

[0040] Figure 4 is a cross-sectional view illustrating a case where the resilient portion is disposed at a side surface of the battery system of the disclosure.

[0041] Figure 5 is a view illustrating Figure 2 a state where the resilient portion is stretched.

[0042] Figure 6 is a view illustrating Figure 3 a state where the resilient portion is stretched.

[0043] Figure 7 is a view illustrating Figure 4 a state where the resilient portion is stretched.

[0044] Figure 8 to Figure 10 is a view illustrating various embodiments of the resilient portion of the disclosure.

[0045] Figure 11 is a view for explaining differences between the resilient portions at various points in the battery system according to an embodiment of the disclosure.

[0046] Figure 12 is a view illustrating a battery pack and a vehicle to which the battery system of the disclosure is applied. DETAILED DESCRIPTION

[0047] In the description of the embodiments disclosed in the present specification, a detailed description of related known technologies will be omitted when it is determined that the detailed description of the related known technologies can obscure the subject matter of the embodiments disclosed in the present specification. Also, it should be understood that the accompanying drawings are provided only for easy understanding of the embodiments disclosed in the present specification by those skilled in the art, and the technical spirit disclosed in the present specification is not limited by the accompanying drawings, and includes all changes, equivalents, and substitutions included in the spirit and technical scope of the disclosure.

[0048] Terms including ordinal numbers such as "first," "second," etc. can be used to describe various constituent elements, but the constituent elements are not limited by the terms. The terms are used only to distinguish one constituent element from another constituent element. A singular expression includes a plural expression unless it is clearly described in the context as a different meaning.

[0049] In the present specification, it should be understood that the terms "comprises", "comprising", "includes", "including", "contains", "containing", "has", "having", or other variations thereof, are inclusive, and therefore specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

[0050] When one constituent element is described as being "coupled" or "connected" to another constituent element, it should be understood that the one constituent element can be directly coupled or connected to the other constituent element, and a middle constituent element can also exist between the constituent elements. When one constituent element is described as being "directly coupled to" or "directly connected to" another constituent element, it should be understood that there is no middle constituent element between the constituent elements.

[0051] Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings. The same or similar constituent elements are assigned the same reference numerals, regardless of the drawings, and repetitive description thereof will be omitted.

[0052] As Figure 1 As shown in FIG. 1, in a battery system, a plurality of battery cells are assembled to constitute a battery module 300, and a plurality of battery modules 300 are assembled to constitute a battery pack. The battery module 300 referred to in the present disclosure refers to an assembly made by assembling a plurality of battery cells, and includes various housings, including a housing in which a plurality of battery cells are stacked and embedded in a separate sealed housing, and a housing in which a plurality of battery cells are assembled in the form of an assembly by a tape, a frame, or the like to define one unit assembly.

[0053] Meanwhile, in the case of thermal runaway in some battery cells or battery modules 300 in the battery pack, gas or flames released from the corresponding battery cell or module 300 can propagate to another adjacent battery cell or module 300 disposed in the battery pack. In this case, since a fire or flames occur in the entire battery pack or the flames or gas attack between adjacent battery cells or adjacent modules 300 can very quickly cause secondary damage due to the external propagation of the fire or flames. Therefore, it is necessary to minimize the possibility of flame propagation from the battery cell or battery module 300 in which thermal runaway occurs to the adjacent battery cell or module 300, and to maximize the delay of flame propagation.

[0054] In the related art, in the case of thermal runaway of some cells or modules 300 in a battery pack, high pressure is generated due to gas or flame released from the corresponding cell or module 300, and a module cover 320 covering the module 300 is separated by the instantaneous high pressure. For this reason, there is a problem that gas or flame spreads to adjacent cells or modules 300, and gas or flame rapidly spreads in the battery pack.

[0055] According to the present disclosure, gas or flame is smoothly discharged from the problematic cell without resistance, and the module cover 320 stably covers the module 300 while pressing the module 300 without separation, so that gas or flame does not spread to adjacent cells or modules 300.

[0056] Specifically, as Figure 1 shown, the module cover 320 is coupled to the battery module 300 of the present disclosure. A plurality of battery cells are assembled to constitute the battery module 300, and the module cover 320 is coupled to the upper end or lateral end of the cell to protect the corresponding battery module 300 in the case of a fire occurring in the adjacent module 300. In the illustrated embodiment, the module cover 320 is coupled to the upper end of the module 300. However, the module cover 320 is not limited thereto, and the module cover 320 can be fixed to various points such as the lateral or lower end of the module 300, and cover the cells constituting the module 300.

[0057] Meanwhile, since the module cover 320 needs to protect the cells of the battery module 300 from gas or flame, the module cover 320 can be made of a fire-resistant material such as mica (mica material). The module cover 320 made of the above-described material prevents high-temperature external gas or flame from being introduced into the corresponding module 300.

[0058] In addition, the module cover 320 needs to be configured to discharge gas or flame in the case of thermal runaway in the battery cell. Therefore, as Figure 1 shown, an exhaust portion 322 is formed on the module cover 320. In general, the exhaust portion 322 covers the battery module 300 to prevent external gas or flame from being introduced. In the case of thermal runaway in the cell positioned below the exhaust portion 322, only the exhaust portion 322 provided at a necessary point needs to operate to allow gas or flame generated therein to be discharged. For this reason, as shown, only a portion of the exhaust portion 322 has a cut shape, so that the exhaust portion 322 is outwardly opened only as needed. In addition, the exhaust portion 322 having various shapes can be applied as long as the exhaust portion 322 satisfies the condition that the exhaust portion 322 is appropriately used to perform a covering operation in general and is opened by high pressure only as needed.

[0059] In the event of thermal runaway in a battery cell located below the vent 322, the vent 322 separates from the module cover 320, forming a vent hole. Gases and flames generated in the cell are discharged to the outside of the module 300 through the formed vent hole. Furthermore, since it is necessary to prevent the flame from propagating to adjacent battery cells while it is being discharged through the vent hole, the module cover 320 needs to properly vent the flame at the point where high voltage is applied and properly cover the battery cells at adjacent points to prevent flame propagation. In other words, even if a high-temperature, high-pressure environment is established within the module cover 320, the module cover 320 still needs to properly press against the module 300.

[0060] In related technologies, to achieve the aforementioned function, a foam rope made of a material such as foamed silicone resin is applied to press the module cover 320 against the battery pack cover 140. However, a problem exists that the foam rope deforms thermally under high temperatures due to thermal runaway, which reduces the pressure. Furthermore, due to the reduced pressure from the foam rope, the module cover 320 separates, and gas or flame propagates to adjacent cells or modules 300. This increases the risk of structural collapse in the battery pack and fails to adequately guarantee the stability of the battery pack.

[0061] Therefore, in this disclosure, the pressing operation is performed by a fire-resistant material instead of foam rope. Furthermore, a cap made of fire-resistant insulating material is also used to support the component performing the pressing operation on the module cover 320 or the battery pack housing 100. Thus, even in the event of a flame, the module cover 320 is consistently pressed down without changing its elasticity, thereby preventing flame propagation and performing the pressing operation without reducing the venting effect in related technologies. Moreover, even if a metal material is used to perform the pressing operation to ensure fire resistance, the risk of a short circuit between the module 300 and the battery pack housing 100 is also reduced because the cap used to support the metal material is made of insulating material.

[0062] Specifically, this disclosure proposes a battery system including an elastic portion 500 supported between a battery pack housing 100 and a battery module 300, and the end of the elastic portion 500 is supported by a cap made of a refractory material.

[0063] The battery module 300 includes a module cover 320, and an exhaust portion 322, including an exhaust port, is disposed on the outer surface of the battery module 300 facing the battery pack housing 100. In the event of thermal runaway in the battery cell, gas or flames can be discharged to the outside through the exhaust port. Figure 1 As shown, the elastic portion 500 is positioned to avoid the exhaust portion 322. This arrangement allows for the smooth release of gas or flame to the outside in the event of thermal runaway within the battery cell, and effectively prevents the flame from spreading to adjacent battery cells or modules 300.

[0064] As Figure 5 illustrated, the elastic part 500 includes first and second caps 520 and 560 at both opposite ends and an elastic body 540. The elastic body 540 is located between the first and second caps 520 and 560. The first and second caps 520 and 560, which are both opposite ends of the elastic part 500, can be made of a fire-resistant material because the first and second caps 520 and 560 need to prevent the spread of gas or flame to adjacent cells or modules 300 in the event of thermal runaway in the battery cell or battery module 300. In addition, the caps at the end portions can be made of mica or the like, i.e., a fire-resistant material, because the caps need to be lightweight and ensure insulation.

[0065] The elastic body 540 of the elastic part 500 that performs the pressing operation can be considered a spring or the like made of a metal material because the elastic body 540 needs to be strong even against high-temperature, high-pressure gas or flame. However, since in the case of using the elastic body 540 made of a metal material, insulation between the battery pack case 100 and the battery module 300 must be ensured, the caps covering both opposite end portions of the elastic part 500 need to have insulation as well as fire resistance. Through such a selection of the cap material, the elastic part 500 of the present disclosure transmits the necessary pressure to the module 300 and ensures insulation in the event of thermal runaway. Of course, the battery system of the present disclosure is not limited to the above-described materials or shapes.

[0066] The battery pack case 100 can include a case main body 120 and a battery pack cover 140 to achieve assemblability. The case main body 120 can have a shape with an opening at its upper or lower side, or in some cases, a shape with an opening at its side. The battery pack cover 140 serves to close the open side of the case main body 120. As Figure 1 illustrated, the case main body 120 has an internal space defined by a bottom surface and a side wall, and has a shape with an opening at its upper side. The battery module 300 is installed in the case main body 120 through the open upper side. In addition, the open upper side of the case main body 120 is closed by the battery pack cover 140. Since a high-temperature high-pressure environment is established in the battery pack case 100 in the event of thermal runaway of the battery module 300, in the event that gas or flame is generated in the battery cell or battery module 300 through thermal runaway, the battery pack cover 140 can easily be thermally deformed by swelling. This swelling results in a gap between the swollen portion and the module cover 320, and the pressing force for pressing the corresponding module cover 320 is reduced, which can cause the module cover 320 to separate.

[0067] The present disclosure is provided to minimize the risk of heat propagation and smoothly vent gas by preventing the module cover 320 of the battery module 300 from separating even in the event that the case main body 120 or the battery pack cover 140 swells.

[0068] The elastic portion 500 is installed between the battery pack case 100 and the battery module 300, and the first cap 520 of the elastic portion 500 is inserted and fixed into the second cap 560 such that the elastic body 540 is maintained compressed between the first cap 520 and the second cap 560. In the case where thermal runaway occurs in the battery cell or the battery module 300, the battery module 300 or the module cover 320 is separated by high-pressure gas and high-temperature flame, which easily causes the gas or flame to spread to the adjacent cell or module 300. As Figure 3 indicated, in order to prevent the battery module 300 or the module cover 320 from being separated even in the case of thermal runaway, the first cap 520 of the elastic portion 500 can be closely attached to the lower end of the battery pack cover 140, and the second cap 560 can be closely attached to the upper end of the module cover 320. When the first cap 520 of the elastic portion 500 is closely attached to the lower end of the battery pack cover 140 and the second cap 560 is closely attached to the upper end of the module cover 320, the first cap 520 and the second cap 560 can be attached and fixed by an adhesive. In this case, the adhesive can be made of a material having heat resistance, which can withstand a high-temperature high-pressure environment caused by thermal runaway.

[0069] Meanwhile, as Figure 4 indicated, the first cap 520 and the second cap 560 of the elastic portion 500 can also be provided at the side of the present battery system. In this case, the first cap 520 can be closely attached to the side surface of the case body 120, and the second cap 560 can be closely attached to the side surface of the battery module 300. When the first cap 520 is closely attached to the side surface of the case body 120 and the second cap 560 is closely attached to the side surface of the battery module 300, the first cap 520 and the second cap 560 can be attached and fixed by an adhesive. Even in this case, the adhesive needs to be made of a material having heat resistance.

[0070] The elastic portion 500 can be closely attached to the case body 120 or the battery pack cover 140 and closely attached to the battery module 300 or the module cover 320. In this case, since the elastic portion 500 is instantaneously exposed to high pressure or high temperature in the case where thermal runaway occurs in the battery cell or the battery module 300, it is important to fix the first cap 520 and the second cap 560 by using an adhesive having heat resistance. The adhesive having heat resistance needs to be used to fix the elastic portion 500 without deforming the adhesive even in the case of high pressure or high temperature, and the elastic portion 500 can also be fixed without deformation since the first cap 520 and the second cap 560 are made of a fire-resistant material. Thus, the case body 120 or the battery pack cover 140 and the battery module 300 or the module cover 320 can be stably supported even in the case of thermal runaway, which can minimize or temporarily delay the spread of gas or flame to the adjacent cell or module 300.

[0071] Meanwhile, in a case where the elastic portion 500 is stretched before the elastic portion 500 is assembled, the battery pack cover 140 and the case main body 120 are easily assembled by mistake. Therefore, generally, the first cap 520 and the second cap 560 can be assembled to each other while the elastic portion 500 is assembled and after the elastic portion 500 is assembled, and the elastic body 540 can be maintained compressed between the first cap 520 and the second cap 560. Therefore, as Figure 2 illustrated, the first cap 520 of the elastic portion 500 is inserted and fixed into the second cap 560, and the elastic body 540 is maintained compressed between the first cap 520 and the second cap 560.

[0072] However, in a case of thermal runaway, as Figure 5 illustrated, the first cap 520 and the second cap 560 of the elastic portion 500 are separated, and the elastic body 540 is stretched. Therefore, a configuration in which the first cap 520 and the second cap 560 can be separated in a high-temperature environment is required. With reference to Figure 8 , the first cap 520 and the elastic body 540 of the elastic portion 500 can be inserted into the second cap 560 in an interference-fit manner. In this case, the first cap 520 of the elastic portion 500 and the second cap 560 are generally maintained in fit. When the temperature in the battery pack case 100 is increased due to gas or flame generated in the battery cell or the battery module 300, the first cap 520 is extracted from the second cap 560, and the elastic body 540 is stretched and works by the extraction of the first cap 520.

[0073] Since the first cap 520 and the elastic body 540 of the elastic portion 500 need to be inserted into the second cap 560, the inner diameter of the second cap 560 is equal to the outer diameter of the first cap 520. Therefore, the first cap 520 and the second cap 560 are assembled to each other in an interference-fit manner.

[0074] Figure 9is a view illustrating an elastic portion 500 according to another embodiment of the disclosure. In this case, a ring or a protrusion 580 can be formed between the first cap 520 and the second cap 560 and compressed into a catch / fixed shape when the first cap 520 is inserted into the second cap 560. In the case of compression of the catch / fixed shape, the ring or the protrusion 580 softens in the case of high pressure or high temperature caused by thermal runaway, so that the first cap 520 is withdrawn from the second cap 560, and the elastic body 540 is stretched and works by withdrawal of the first cap 520. In the case of the catch / fixed shape, the ring or the protrusion 580 can be formed on the inner surface of the second cap 560 when the second cap 560 is formed, or the ring or the protrusion 580 can be attached to the inner surface of the second cap 560 or the outer surface of the first cap 520. One or more rings or protrusions 580 can exist and be disposed between the first cap 520 and the second cap 560 to improve the coupling property. The catch, fixation, and fastening are achieved by using the ring or the protrusion 580, so that the mutual mechanical connection can be achieved even without a separate adhesive.

[0075] As Figure 10 illustrated, in still another embodiment of the disclosure, the outer surface portion of the first cap 520 and the inner surface portion of the second cap 560 can be fixed by an adhesive 590. In this case, the elastic body 540 works as an adhesive component of the adhesive 590 is melted by a high-temperature gas or a flame. The adhesive 590 serves to fix both opposite ends when the first cap 520 is inserted into the second cap 560. In the case of high pressure or high temperature caused by thermal runaway, the binding force of the adhesive 590 is eliminated, so that the first cap 520 is separated from the second cap 560 and stretched. Accordingly, the adhesive 590 needs to be made of a material that maintains the binding force at room temperature and reduces the binding force in the case of high temperature.

[0076] As Figure 2 and Figure 5 illustrated, the first cap 520 and the second cap 560 are each provided in the form of a closure with one side thereof open. Specifically, the first cap 520 and the second cap 560 each have a bottom surface disposed in surface contact with the housing body 120 or the battery pack cover 140 and the battery module 300 or the module cover 320, and have a side wall connected to the bottom surface. The side opposite to the bottom surface is open, and the open sides of the first cap 520 and the second cap 560 face each other. Of course, in addition to Figure 2The first cap 520 and the second cap 560 can have various shapes other than the circular shape in the center, as long as surface contact can be achieved. Also, the first cap 520 and the second cap 560 can be made of a fireproof material because the first cap 520 and the second cap 560 need to prevent the spread of gas or flames to adjacent cells or modules 300 in the event of thermal runaway in the battery cell or the battery module 300. The first cap 520 and the second cap 560 can be made of mica or the like, i.e., a fireproof material, because the first cap 520 and the second cap 560 need to ensure insulation and be light in weight. With the shape and surface contact method of the first cap 520 and the second cap 560, the assembly stability of the battery system of the present disclosure can be improved, and the elasticity of the elastic portion 500 can be increased in the event of thermal runaway. Thus, the spread of heat to adjacent cells or modules 300 can be minimized or temporarily delayed in the event of thermal runaway.

[0077] The battery pack case 100 can include a case body 120 and a battery pack cover 140 to ensure assemblability. In the case where the battery is installed in a vehicle, collision-related performance can be ensured. Because the spread of fire to the outside needs to be prevented in the event of a fire in the battery, the battery pack case 100 can be made of a metal material. Also, among metal materials, the battery pack case can be made of aluminum because the battery pack case needs to ensure formability and be light in weight. The battery pack case 100 made of a metal material such as aluminum can be thermally deformed due to swelling in a high-pressure or high-temperature environment caused by thermal runaway in some battery cells or battery modules 300, and the amount of swelling can vary depending on the point even in a single battery pack case 100.

[0078] Referring to Figure 11 In the case where the outer portion B is spaced apart from the center of the battery pack case 100, the side surface and the bottom surface of the case shape of the case body 120 are also integral, and the battery pack cover 140 is also coupled to the case body 120 in various ways such as welding, attachment, and mechanical fastening, so that the amount of swelling is relatively small even in the event of thermal runaway. In contrast, in the case of the central portion A of the battery pack case 100, the case body 120 has a large surface shape for installing the battery module 300, and the battery pack cover 140 is not directly coupled to the portion of the case body 120. Therefore, the amount of swelling is maximized in the event of thermal runaway. That is, in the event of thermal runaway, the battery pack cover 140 swells more as the distance from the central portion A decreases.

[0079] A plurality of elastic portions 500 can be disposed between the battery pack case 100 and the battery module 300, and the amount of expansion of the battery pack cover 140 can vary depending on the point. Accordingly, the plurality of elastic portions 500 can be disposed such that an elastic portion having an elastic body 540 with a high modulus of elasticity or a large amount of expansion can be disposed close to the central portion A of the battery pack cover 140. Because the elastic body 540 with a high modulus of elasticity or a large amount of expansion is disposed close to the central portion A of the battery pack cover 140, the elastic force of the elastic portion 500 increases as the distance from the central portion A of the battery pack cover 140 decreases. Accordingly, the elastic portions 500 in the battery pack case 100 can operate in a balanced manner such that the stability of the entire battery system can be sufficiently secured. In this case, in the case in which a plurality of elastic portions 500 exist in the battery pack case 100, in the case in which the elastic body 540 of the elastic portion 500 has a constant length, the elastic force can be adjusted by using materials having different moduli of elasticity. In the case in which the modulus of elasticity of the elastic body 540 is constant, the elastic force can be differently adjusted by changing the compression amount by changing the length of the elastic body 540.

[0080] The module cover 320 is coupled to the battery module 300 of the present disclosure. The module cover 320 covers one side surface of the battery module 300 to protect the battery module 300 and the battery cells positioned in the battery module from gas or flames. The elastic portion 500 can be disposed between the battery pack case 100 and the module cover 320 to prevent gas or flames from spreading to adjacent cells or modules 300 in the case in which thermal runaway occurs in the battery cells or the battery module 300. As shown in FIG. 6, when high-pressure gas or high-temperature flames are generated at this location, the elastic portion 500 is stretched, and the first cap 520 or the second cap 560 of the elastic portion 500 is supported by the battery pack case 100 or the module cover 320 such that the module cover 320 is pressed based on the battery pack case 100, and gas or flames are prevented from being introduced into the corresponding battery module 300. Figure 6

[0081] ​Further, as another embodiment, the elastic portion 500 is disposed between the battery pack case 100 and the module cover 320, and one end of the elastic portion 500 is sometimes fixed to the module cover 320 only. As described above, the amount of expansion caused by thermal runaway in the battery pack case 100 can vary depending on the point. Also, because the amount of expansion increases as the distance from the center portion A of the battery pack cover 140 decreases, the battery pack cover 140 expands in an arcuate shape. Thus, during expansion, the center portion A of the battery pack cover 140 expands in the form of a horizontal surface. In contrast, points other than the center portion expand in the shape of a surface that is inclined in the diagonal direction. In this case, when the elastic portion 500 is attached to the battery pack case 100 as well as the module cover 320, the surface of the elastic portion 500 attached to the surface of the battery pack case 100 that is inclined in the diagonal direction of the battery pack case 100 becomes unstable when the battery pack case 100 expands due to thermal runaway, and the battery module 300 or the module cover 320 can not be sufficiently pressed based on the battery pack case 100. Thus, in a state in which one end of the elastic portion 500 is fixed to the module cover 320 and the other end of the elastic portion 500 is spaced apart from the battery pack case 100, the elastic portion 500 can be fixed to the module cover 320 only. Thereafter, in the case where thermal runaway occurs in the battery cell or the battery module 300, the elastic portion 500 is stretched by the gas or flame in the battery pack case 100. In the case where the elastic portion 500 is stretched, such that both opposite ends of the elastic portion 500 can be supported on the battery pack case 100 and the module cover 320, and the module cover 320 is sufficiently pressed based on the battery pack case 100.

[0082] Meanwhile, the battery pack case 100 can include a case body 120 that is open at one side thereof, and a battery pack cover 140 configured to close the open side of the case body 120. An elastic portion 500 can be disposed between the battery pack cover 140 and the battery module 300. In the case where high-pressure gas or high-temperature flame is generated by thermal runaway in the battery cell or the battery module 300, the battery pack cover 140 expands. As the battery pack cover 140 expands, the distance between the battery pack cover 140 and the battery module 300 also increases, and the elastic portion 500 disposed between the battery pack cover 140 and the battery module 300 is stretched by the distance by which the battery pack cover 140 and the battery module 300 are spaced apart from each other, such that both opposite ends can be supported on the battery pack cover 140 and the battery module 300, respectively. Thus, the elastic portion 500 can press the battery module 300 based on the battery pack cover 140, and prevent the gas or flame from spreading to the adjacent battery cell or battery module 300 and temporarily delay heat propagation.

[0083] The battery system according to the present disclosure can be applied to a battery system of various vehicles such as an internal combustion engine vehicle, an electric vehicle, a hybrid vehicle, and a fuel cell electric vehicle. In addition to the vehicle, the battery system can be applied to a battery system in various fields such as an industrial energy storage system (ESS) or a home ESS and a small-scale battery pack.

[0084] While specific embodiments of the present disclosure have been shown and described, it will be apparent to those of ordinary skill in the art that various modifications and changes can be made to the present disclosure without departing from the technical spirit of the present disclosure as defined in the appended claims.

Claims

1. A battery system, the battery system comprising: Battery module; A battery pack housing, in which the battery module is disposed; as well as An elastic portion is disposed between the battery pack housing and the battery module and is configured to press the battery module based on the battery pack housing. The end of the elastic portion is supported on the battery pack housing or the battery module by means of a cap made of refractory material.

2. The battery system according to claim 1, wherein, An exhaust portion is formed on the outer surface of the battery module facing the battery pack housing, and the elastic portion is disposed at a position avoiding the exhaust portion.

3. The battery system according to claim 1, wherein, The elastic part is composed of a first cap, a second cap, and an elastic body, and the elastic body is located between the first cap and the second cap.

4. The battery system according to claim 3, wherein, The first cap of the elastic portion is tightly attached to the inner surface of the battery pack housing, and the second cap of the elastic portion is tightly attached to the outer surface of the battery module.

5. The battery system according to claim 3, wherein, The first cap of the elastic portion or the second cap of the elastic portion is attached to the inner surface of the battery pack housing or the outer surface of the battery module by an adhesive, and the adhesive is made of a heat-resistant material.

6. The battery system according to claim 3, wherein, The first cap of the elastic portion is fixed in a state where it is inserted into the second cap, thereby maintaining the elastic body in a compressed state between the first cap and the second cap, and The first cap of the elastic part is pulled out from the second cap by the gas or flame generated in the battery module or the increase in the internal temperature of the battery pack casing, and the elastic body is stretched by the pull-out of the first cap.

7. The battery system according to claim 6, wherein, The first cap of the elastic part is locked and fixed when inserted into the second cap, and the first cap separates from the second cap when the second cap expands due to high temperature.

8. The battery system according to claim 6, wherein, The first cap of the elastic part is bonded and fixed when it is inserted into the second cap, and the first cap separates from the second cap when the adhesive force is eliminated due to high temperature.

9. The battery system according to claim 1, wherein, The elastic portion, comprising multiple elastic portions, is disposed between the battery pack housing and the battery module. The elastic force of the elastic portion increases as the elastic portion approaches the center of the battery pack housing. The elastic portion near the center of the battery pack housing has a larger elastic modulus or a larger compressibility than the elastic portion farther from the center of the battery pack housing.

10. The battery system according to claim 1, wherein, The module cover is attached to the battery module to cover one side of the battery module, and the elastic portion is disposed between the battery pack housing and the module cover. The elastic part is located between the battery pack housing and the module cover and is fixed to the module cover.

11. The battery system according to claim 10, wherein, One end of the elastic part is fixed to the module cover, and the other end of the elastic part is spaced apart from the battery pack housing.

12. The battery system according to claim 10, wherein, The elastic portion is stretched by gas, flame, or high temperature in the battery pack housing, and the two opposite ends of the elastic portion are supported on the battery pack housing and the module cover, respectively, when the elastic portion is stretched.

13. The battery system according to claim 1, wherein, The battery pack housing includes: A housing body, with an opening on one side of the housing body; and A battery pack cover, configured to close the housing body, and The elastic part is located between the battery pack cover and the battery module.

14. The battery system according to claim 13, wherein, When gas, flame, or high temperature is present in the battery pack housing, the gap between the battery pack cover and the battery module increases due to the expansion of the battery pack cover. The elastic part is stretched to the extent that the gap between the battery pack cover and the battery module increases, and the elastic part presses the battery module based on the battery pack cover.

15. A vehicle comprising the battery system according to claim 1.

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