Battery system and vehicle including same

Abstract

Disclosed are a battery system and a vehicle including same, the battery system comprising: a battery module having venting parts formed on one surface thereof; a pack case having the battery module installed therein; and resilient parts provided on one surface of the battery module, disposed at points that do not overlap with the venting parts, and parts of which protrude toward the pack case and are supported, thereby pressing one surface of the battery module relative to the pack case.

Description

Battery system and vehicle including same

[0001] The present invention relates to a battery system with improved safety in an abnormal battery situation and a vehicle including the same.

[0002] Recently, technologies for carbon reduction are being actively developed to address environmental issues such as extreme temperatures. To achieve this, energy must be produced using environmentally friendly methods rather than relying on fossil fuels. This energy must be stored as electricity, and the stored electricity must be used in vehicles, various industrial sites, and homes.

[0003] To utilize electric energy for carbon reduction, the use of batteries capable of storing and releasing electric energy is essential. Therefore, ensuring battery performance is essential to sufficiently store electric energy and ensure hassle-free use.

[0004] Batteries primarily utilize redox reactions of metal ions. To increase battery capacity, charge / discharge performance, and efficiency, high-density metal ions are used. Extensive research is also being conducted on electrolyte components and solid electrolytes. However, as battery performance advances, stability generally declines.

[0005] Batteries used in vehicles, industrial applications, and homes are manufactured as physical units called packs. Battery packs contain multiple battery cells within a sealed case, preventing fire from spreading to the outside in the event of a battery overheating or other accident. They also protect the internal battery cells from deterioration caused by the external environment or physical damage.

[0006] A battery pack contains multiple battery cells, housed in an intermediate form called a module or assembly (CMA, Cell Module Assembly). A battery module or assembly is composed of multiple battery cells assembled into a single module or assembly. These modules are then fastened within the pack case, completing the battery pack. Maintenance is facilitated by allowing maintenance to be performed on a module or assembly basis.

[0007] The multiple unit battery cells that make up a module or assembly are comprised of anodes, cathodes, and electrolytes. Because battery cells generate heat during charging and discharging, effective heat dissipation is essential. Furthermore, from the perspective of battery modules, assemblies, and battery packs, designing for efficient heat dissipation is essential to prevent safety accidents.

[0008] Meanwhile, batteries can deteriorate due to manufacturing errors, excessive charging and discharging, and aging. If battery deterioration persists, it can ultimately lead to fire. Therefore, proactive measures are necessary to prevent battery fires. To achieve this, it's crucial to continuously monitor the battery's condition, proactively detect and respond to problems, and minimize damage in the event of an unexpected problem.

[0009] In particular, when a flame occurs in a specific cell of a specific module among multiple battery modules within a battery pack, the flame must be prevented from spreading to other adjacent battery cells, and the flame must also be prevented from spreading to other adjacent modules. Therefore, from the perspective of the battery module, the gas venting of the defective battery cell must be smooth, while preventing or delaying the venting gas or flame from affecting other cells or modules as much as possible.

[0010] The matters described as background technology above are only intended to enhance understanding of the background of the present invention, and should not be taken as an admission that they correspond to prior art already known to those of ordinary skill in the art.

[0011] The present invention has been proposed to solve these problems, and aims to provide a battery system and a vehicle including the same that can improve battery safety by preventing flame spread to adjacent cells or modules when a fire occurs in a specific battery cell or battery module while facilitating gas venting.

[0012] The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0013] In order to achieve the above object, the battery system according to the present invention comprises: a battery module having a venting portion formed on one surface; a pack case having the battery module installed therein; and an elastic member provided on one surface of the battery module, positioned at a point that does not overlap with the venting portion, and supported by protruding a portion toward the pack case to pressurize one surface of the battery module with respect to the pack case.

[0014] In the battery system according to the present invention, a plurality of venting parts are provided spaced apart from each other on one side of the battery module, and the elastic part can be positioned between the plurality of venting parts in a grid shape.

[0015] In the battery system according to the present invention, among the plurality of venting portions formed on one surface of the battery module, the outermost venting portion is provided adjacent to the edge of the battery module, and the elastic portion may be provided at a point inside the outermost venting portion.

[0016] In the battery system according to the present invention, the elastic portion is composed of a base portion and a support portion, and the support portion can be supported by the pack case by bending a part of the base portion in the direction of the pack case.

[0017]

[0018] *In the battery system according to the present invention, an insulating part is provided in the elastic part, and the insulating part is formed of a fire-resistant material and can be placed between the base part and the battery module.

[0019] In the battery system according to the present invention, the insulating part of the elastic part can be in close contact with one surface of the battery module, and the end of the supporting part can be supported on the inner surface of the pack case.

[0020] In the battery system according to the present invention, the base of the elastic portion may be made of a metal material, and the support portion may be formed integrally with the base portion.

[0021] In the battery system according to the present invention, a bead protruding along the direction in which the base portion extends may be provided on the base portion of the elastic portion.

[0022] In the battery system according to the present invention, the bead may be formed on the base portion and extended to the support portion.

[0023] In the battery system according to the present invention, the beads may be formed to protrude in the direction of the pack case.

[0024] In the battery system according to the present invention, the support portion of the elastic member may be pressurized by the pack case when the pack case is not expanded, thereby forming a pre-pressure toward the battery module.

[0025] In the battery system according to the present invention, when the pack case expands, the support portion of the elastic member can maintain support for the pack case and the angle of bending toward the pack case can increase.

[0026] In the battery system according to the present invention, the support portion of the elastic portion may be supported by an elastic body on one side of the battery module.

[0027] In the battery system according to the present invention, the elastic body is stretched when the pack case expands, and the support part can be elastically supported toward the pack case by the elastic body.

[0028] In the battery system according to the present invention, a plurality of support members of the elastic member are provided, and the length or bending angle of the plurality of support members may increase as they get closer to the central part of the pack case.

[0029] In the battery system according to the present invention, the base portion of the elastic portion is composed of a plurality of first frames spaced apart from each other and extending across the battery module in the width direction, a plurality of second frames extending in a direction intersecting the first frames and connecting the first frames, and a part of the second frames may be bent toward the pack case to form a support portion.

[0030] In the battery system according to the present invention, the second frame may have one or the other end bent to form a support portion, and the support portions of a pair of adjacent second frames may be formed to be misaligned at each end and the other end.

[0031] In the battery system according to the present invention, the outermost second frames among the plurality of second frames can have their outermost ends all bent to form a support.

[0032] In the battery system according to the present invention, the pack case may have one side open, the open side may be closed by a pack lid, and an elastic member may be provided between the pack lid and the battery module.

[0033] In the battery system according to the present invention, a module cover having a plurality of venting portions formed on one side of a battery module is provided, and an elastic portion can be placed at a point between the pack case and the module cover, avoiding the venting portions.

[0034] The vehicle according to the present invention includes a battery system as described above.

[0035] According to the battery system of the present invention and the vehicle including the same, when a fire occurs in a specific battery cell or battery module, the flame spread to other adjacent cells or modules is prevented, and at the same time, in the case of a problematic battery cell or battery module, gas venting is facilitated, thereby improving the safety of the battery system and the upper system utilizing the same as a whole.

[0036] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0037] Figure 1 is a drawing showing a battery system according to one embodiment of the present invention.

[0038] Fig. 2 is a drawing showing an elastic part of the battery system illustrated in Fig. 1.

[0039] FIG. 3 is a cross-sectional view taken along line A-A' of the battery system illustrated in FIG. 2.

[0040] Fig. 4 is a cross-sectional view of the battery system of the present invention depending on whether the pack case is expanded.

[0041] FIG. 5 is a drawing showing a case where the elastic part of the battery system of the present invention is provided on the side of the battery module.

[0042] FIG. 6 is a cross-sectional view of a battery system according to another embodiment of the present invention depending on whether the pack case is expanded.

[0043] FIG. 7 is a drawing for explaining the difference in elasticity at each point in a battery system according to one embodiment of the present invention.

[0044] Figure 8 is a drawing showing a battery pack and a vehicle to which the battery system of the present invention is applied.

[0045] In describing the embodiments disclosed in this specification, detailed descriptions of related known technologies will be omitted if it is determined that such detailed descriptions may obscure the gist of the embodiments disclosed in this specification. In addition, the attached drawings are provided solely to facilitate understanding of the embodiments disclosed in this specification, and the technical concepts disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, and substitutes included within the spirit and technical scope of the present invention.

[0046] Terms that include ordinal numbers, such as "first," "second," etc., may be used to describe various components, but these components are not limited by these terms. These terms are used solely to distinguish one component from another. Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0047] In this specification, terms such as "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and should be understood as not excluding in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. The suffixes "module" and "part" used for components in the following description are given or used interchangeably only for the convenience of writing the specification, and do not in themselves have distinct meanings or roles.

[0048] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0049] Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. Regardless of the drawing reference numerals, identical or similar components are given the same reference numerals and redundant descriptions thereof will be omitted. A battery is composed of a plurality of battery cells that form a battery module (300), and a plurality of battery modules (300) that form a battery pack (BP). The battery is subjected to stress due to defects in design or manufacturing, excessive charging or discharging, misuse, etc., and if such stress continues, the battery cells deteriorate. When the battery cells deteriorate and a certain temperature is maintained above the set point, the flammable electrolyte inside the battery cells vaporizes and ejects, and the pressure inside the cells increases, causing a fire inside the battery cells. This soon leads to a fire in adjacent battery cells, and as the fire spreads between cells, it spreads to a fire between battery modules (300), resulting in a thermal runaway phenomenon. In the event of thermal runaway of such a battery cell or battery module (300), it is important to prevent or delay the spread of gas or flame to adjacent cells or modules (300) while ensuring smooth discharge of gas in a desired direction.

[0050] The present invention is to prevent one side of a battery module (300) from being lifted due to high temperature or high pressure when a thermal runaway occurs due to a fire in a battery cell or battery module (300), thereby facilitating gas venting inside a cell or module (300) where a thermal runaway has occurred, while preventing the spread of gas or flame to adjacent cells or modules (300), thereby improving the performance and safety of a battery pack (BP).

[0051] Specifically, the battery module (300) of the present invention includes a module cover (320) as shown in FIG. 1. The module cover (320) is coupled to one side of the battery cells to protect the battery module (300) and battery cells from gas or flames from adjacent battery cells or battery modules (300), and a venting portion (340) is included on one side of the module cover (320) to smoothly vent gas or flames generated when a battery cell inside the battery module (300) experiences thermal runaway.

[0052] In addition, the module cover (320) may be formed of a heat-resistant and insulating material such as mica (a mica material) to prevent gases or flames generated due to thermal runaway in adjacent battery cells or battery modules (300) from spreading to the corresponding cells or modules (300). In the case of Fig. 1, the module cover (320) is positioned on top of the battery cells to protect the cells. The module cover (320) is not necessarily limited to the illustrated embodiment in order to perform the role of protecting the cells and the module (300), and may cover the battery module (300) at various points, such as the side or bottom of the battery module (300), to protect the battery cells inside.

[0053] Meanwhile, a venting portion (340) is formed in the battery module (300) to discharge gas or flame generated in the event of thermal runaway in the battery cell or battery module (300). Referring to FIG. 1, the venting portion (340) is formed in the module cover (320) of the battery module (300), and a venting hole is formed when the venting portion (340) is removed. The venting hole is formed on the outer surface of the battery module (300) and serves to discharge gas or flame generated in the interior of the module (300), and a plurality of venting holes may be present to ensure smooth discharge of gas or flame. In addition, the venting hole must be able to vent smoothly in case of thermal runaway in the cell or module (300), but in case of thermal runaway in an adjacent cell or module (300), the module cover (320) must protect the cells inside, so the venting part (340) has a shape that is partially cut out in the module cover (320). That is, in the case of the venting hole, it is normally blocked by the venting part (340) to protect the cells inside the module (300), and only in high temperature or high pressure situations, the partially cut venting part (340) is completely cut out and opened as a venting hole for the discharge of gas or flame. In addition, if the module cover (320) satisfies the condition of protecting the cells or module (300) inside well in normal times and opening only when necessary, various types of venting parts (340), such as not only a partial cut but also an adhesive or a fitting joint, can be applied to the module cover (320).

[0054] Meanwhile, superior battery performance means a high energy density. A battery pack (BP) is composed of multiple battery modules (300), and these modules (300) are formed by combining multiple battery cells. Therefore, densely stacking the battery cells is a way to increase the energy density of the battery itself. Therefore, to achieve superior battery performance, the battery module (300) must have as many battery cells as possible stacked at a high density.

[0055] The venting portion (340) is formed on the outer surface of the battery module (300) or the module cover (320) to discharge gas or flame generated when the battery cell thermally runs away, and is positioned at a location corresponding to where the battery cells are located inside the module (300). In addition, in order to secure excellent battery performance, as many battery cells as possible are stacked at a high density in the battery module (300), and as a result, the battery cells are arranged all the way to the outermost part inside the battery module (300). Therefore, in the case of the module (300) or the module cover (320), in order to facilitate venting of gas or flame generated when the battery cells arranged at the outermost part thermally run away, a venting portion (340a) is also provided at the outermost part of the module (300) or the module cover (320), as shown in FIG. 1.

[0056] In the case of the present invention, an elastic member (500) is provided on one side of the battery module (300) and is positioned at a point that does not overlap with the venting member (340) to pressurize the module (300) and thereby prevent the module (300) from being lifted. In addition, the elastic member (500) is made of a heat-resistant metal material and can pressurize the battery module (300) without changing its physical properties even in a high-temperature environment due to thermal runaway. In addition, the configuration that performs the pressing includes an insulator (560) that is equipped with fire resistance, so that an electrical short between the battery module (300) and the pack case (100) can be prevented.

[0057] Specifically, the present invention provides a battery system including an elastic member (500) positioned between a pack case (100) and a battery module (300), wherein the elastic member (500) is positioned in a space that does not overlap with a venting member (340) on one side of the battery module (300), and a part of the elastic member (500) protrudes toward the pack case (100) and is supported.

[0058] In the present invention, the battery module (300) includes a module cover (320), and a plurality of venting portions (340) are formed spaced apart from each other on the outer surface of the module (300) or the module cover (320). The venting portions (340) include venting holes through which gas or flame is discharged to the outside when a battery cell experiences thermal runaway. The elastic portions (500) are positioned in a grid shape at a point avoiding the venting portions (340) on one surface of the module (300), as shown in FIG. 1. Through the elastic portions (500) arranged in a grid shape, gas or flame is smoothly discharged from the venting portions (340), and the phenomenon of the battery module (300) or the module cover (320) being lifted due to high temperature or high pressure is prevented, thereby effectively preventing the spread of gas or flame to adjacent cells or modules (300).

[0059] To improve battery performance, battery cells are stacked at a high density inside a battery module (300). The venting portion (340) located on one side of the module (300) is intended to facilitate the discharge of gas or flames in the event of thermal runaway of the cells located inside the module (300), and must be formed at a location corresponding to the location of the cells on one side of the module (300). Accordingly, a venting portion (340a) is also formed on the outermost part of the module (300) to discharge gas or flames generated in the event of thermal runaway of the battery cells stacked at a high density.

[0060] Since the outermost venting portion (340a) is formed adjacent to the edge of the battery module (300), the elastic portion (500) is provided on the inside of the module (300) or the module cover (320) based on the outermost venting portion (340a) and is arranged in a grid shape between a plurality of venting portions (340) located on the inside. Since the elastic portion (500) is arranged at a point that avoids the venting portion (340) through the grid-shaped arrangement, the venting of gas or flame generated during thermal runaway is smoothly possible, and at the same time, the battery module (300) can be effectively pressurized. In addition, since the elastic portion (500) is provided on the inside of the outermost venting portion (340a), the battery cells existing inside the module (300) can be densely stacked, which can also help improve the overall battery performance.

[0061] The elastic part (500) is composed of a base part (520) and a support part (540), and the support part (540) is supported by the pack case (100) by bending a part of the base part (520) toward the pack case (100). The elastic part (500) is made of a metal material that can withstand a high temperature or high pressure environment due to thermal runaway generated in a battery cell or battery module (300), and the support part (540) is formed by bending a part of the base part (520) and can be formed integrally with the base part (520). The elastic part (500) can be formed by forming a base part (520) of a metal material into a grid shape through a press punching method, cutting a part of the base part (520) to form the support part (540), and then bending the cut part. Since the elastic part (500) is formed integrally with the base part (520) and the support part (540), the support part (540) can effectively transmit the pressure received from the pack case (100) to the base part (520), thereby sufficiently pressurizing the battery module (300).

[0062] In addition, the elastic part (500) includes an insulating part (560). The base part (520) and the support part (540) of the elastic part (500) are formed of a conductor made of a metallic material and therefore have excellent electrical conductivity. If insulation is not provided when using such a conductor, an electrical short may occur inside the pack case (100), and when an electrical short occurs, a large current may flow in the conductor, which may cause the battery and the conductor to deteriorate or catch fire, resulting in secondary damage. Therefore, the elastic part (500) must include an insulating part (560) in addition to the base part (520) and the support part (540), and the insulating part (560) is positioned between the base part (520) and the battery module (300) to prevent an electrical short between the module (300) and the pack case (100). In addition, the insulation part (560) must perform the insulation function even in a high-temperature environment due to thermal runaway of the battery cell or battery module (300), and thus may be manufactured from a fire-resistant material such as mica (a mica material). Of course, the battery system of the present invention is not limited to the materials or shapes presented above.

[0063] Meanwhile, a bead (580) is provided on the base portion (520) of the elastic portion (500) so as to protrude along the direction in which the base portion (520) extends, as shown in FIG. 2. The elastic portion (500) includes a base portion (520) made of a metal material, and the base portion (520) made of a metal material may be physically deformed, such as twisted or folded, in a high-temperature or high-pressure environment that occurs when a battery cell or battery module (300) experiences thermal runaway. When the base portion (520) is physically deformed by gas or flame caused by thermal runaway, the battery module (300) cannot be sufficiently pressurized, causing the module (300) to lift, thereby facilitating the propagation of gas or flame to adjacent cells or modules (300).

[0064] Therefore, in order to prevent deformation of the base part (520), a bead (580) may be formed so that the central portion of the base part (520) protrudes as shown in FIGS. 2 and 3. The bead (580) can be integrally formed to protrude from the base part (520) during the lattice-shaped forming process of the elastic part (500), and can be formed of the same material as the base part (520). By forming the bead (580) on the base part (520), the elastic part (500) prevents the base part (520) from being easily deformed even in a high temperature or high pressure environment due to thermal runaway, thereby sufficiently pressurizing the battery module (300). In addition, the bead (580) may be formed on one surface of the second frame (524) along the direction in which the base part (520) extends as shown in FIG. 2, and may also be present on one surface of the first frame (522) intersecting the second frame (524).

[0065] In addition, the bead (580) can be formed to protrude from the base portion (520) toward the pack case (100) as shown in FIG. 3, and can also be formed to protrude in the opposite direction toward the battery module (300), and can also be formed to protrude on both sides. Since the support portion (540) of the elastic portion (500) can be formed integrally with the base portion (520), the bead (580) can be formed to extend not only to the base portion (520) but also to the support portion (540). When extended to the support portion (540), the cross-section of the support portion (540) is formed in a form in which a protruding bead (580) is formed as shown in FIG. 3, and can be bent in this form toward the pack case (100) or toward the battery module (300).

[0066] In the case of the elastic part (500), as shown in FIG. 4, it is installed between the pack case (100) and the battery module (300), the insulating part (560) of the elastic part (500) is in close contact with one surface of the battery module (300), and the end of the support part (540) of the elastic part (500) is supported and fixed to the inner surface of the pack case (100).

[0067] In the battery system of the present invention, the pack case (100) is composed of a case body (120) and a pack lid (140), and the battery module (300) includes a module cover (320). Accordingly, the elastic member (500) may be positioned between the pack lid (140) and the module cover (320) as shown in FIG. 4, or may be formed between the case body (120) and the battery module (300) as shown in FIG. 5. In this case, the insulating member (560) of the elastic member (500) is in close contact with one surface of the module cover (320) or the module (300), and the support member (540) of the elastic member (500) may be supported and fixed at an end thereof to the inner surface of the pack lid (140) or the case body (120).

[0068] Specifically, before the pack case (100) expands, the support part (540) of the elastic part (500) is pressed by the pack case (100) toward the battery module (300), as shown in the dotted line of FIG. 4, to maintain a state in which a preload is formed. Since the elastic part (500) is made of a metal material and has restoring force, when the pack case (100) presses the elastic part (500) toward the battery module (300), the state in which the elastic force is stored can be maintained. Thereafter, when thermal runaway occurs in the battery cell or battery module (300), the pack case (100) expands due to high-pressure gas or high-temperature flame, as shown in the solid line of FIG. 4, and in the case of the present invention, when the pack case (100) expands due to thermal runaway, the stored elastic force in the elastic part (500) in which the preload was formed is applied. Therefore, even in the event of thermal runaway, the support portion (540) of the elastic portion (500) can still maintain support for the pack case (100), and since the support portion (540) is supported by the pack case (100), it can continuously pressurize the module cover (320), thereby preventing the module cover (320) from being lifted off the top of the battery module (300). If the module cover (320) is lifted due to flame or gas, gas or flame is ejected between the module cover (320) and the top of the module (300), which means that gas and flame are ejected in a direction that was not originally intended. This can cause flame propagation to other adjacent modules (300) or cells. Accordingly, as in the present invention, the module cover (320) stably presses the top of the module (300) to prevent it from being lifted, thereby minimizing or temporally delaying the spread of gas or flame to adjacent cells or modules (300).

[0069] Fig. 6 is a drawing showing an elastic member (500) according to another embodiment of the present invention. In this case, the support member (540) of the elastic member (500) is supported by an elastic body (590) located on one side of the battery module (300), and the elastic body (590) is placed between the support member (540) of the elastic member (500) and the battery module (300). Before the pack case (100) expands, the pack case (100) presses the support member (540) toward the battery module (300), as shown by the dotted line in Fig. 6, so that the elastic body (590) maintains a contracted state. When the pack case (100) expands due to thermal runaway in the battery cell or battery module (300), not only the support part (540) but also the elastic body (590) expands together, as shown in the solid line portion of FIG. 6, and since the support part (540) is elastically supported by the elastic body (590), it is possible to maintain more solid support for the pack case (100). In this case, the elastic body (590) may be provided as a spring made of a metal material that can withstand high temperature or high pressure, and in some cases, a plurality of such springs may be required. In the case where the metal elastic body (590) is used, an insulating part (560) must be provided between the elastic part (500) and the battery module (300) to ensure insulation between the pack case (100) and the battery module (300). By adding an additional elastic body (590) to the elastic part (500) in this way, the support force of the elastic part (500) can be secured to be greater, and when a plurality of elastic parts (500) are applied to one module (300), it is possible to create a difference in elasticity between the elastic parts (500) by applying the elastic body (590) only to some of the elastic parts (500).

[0070] The pack case (100) may be composed of a case body (120) and a pack lid (140) for assembly. The case body (120) may have an open side, and the pack lid (140) functions to close the open side of the case body (120). As shown in Fig. 1, when the case body (120) has an open top, an internal space is formed by the bottom and side walls, and the battery module (300) is mounted inside through the top side. In addition, the pack lid (140) closes the top side of the case body (120), thereby protecting the battery module (300).

[0071] In the case of a battery mounted on a vehicle (V), the performance against collision must be secured and secondary damage must be prevented in the event of a fire, so the pack case (100) can be formed of a metal material. In addition, it can be manufactured from aluminum, which is easy to form, lightweight, and durable among metals. In a high temperature or high pressure environment due to thermal runaway in some battery cells or battery modules (300), a pack case (100) made of a metal material such as aluminum may experience thermal deformation due to expansion. Due to this thermal deformation, the gap between the expanded pack lid (140) and the module cover (320) may widen, and the lifting phenomenon of the module cover (320) at that point may increase. In addition, the amount of expansion of the pack lid (140) may vary depending on the point within one pack case (100). Therefore, the elastic member (500) of the present invention also needs to be formed differently depending on the point to support the module cover (320).

[0072] Referring to Fig. 7, the expansion amount of the outer portion (B) away from the center of the pack case (100) is relatively smaller than that of the center portion (A). The outer portion (B) of the case body (120) is formed in a housing shape in which the bottom surface and the side walls are integrally formed, and the outer portion (B) of the pack lid (140) is also connected to the case body (120) in various ways such as welding, adhesion, and mechanical fastening, so even if thermal runaway occurs in some battery cells or battery modules (300), the expansion amount of the outer portion (B) of the pack case (100) is limited. On the other hand, in the case of the center portion (A) of the pack case (100), the case body (120) is formed in a wide surface shape for mounting the battery module (300), and the pack lid (140) is not directly connected to the case body (120), so when thermal runaway occurs, the expansion amount becomes the point at which it is maximum. That is, when thermal runaway occurs, the pack lead (140) expands more as it gets closer to the center (A).

[0073] When considering that a plurality of support members (540) of the elastic member (500) may be provided between the pack case (100) and the battery module (300) and that the expansion amount of the pack lid (140) is different at each point, it is important to select different support members (540) at each point to support the expanded pack lid (140) in a balanced manner when the pack lid (140) expands due to thermal runaway in the battery cell or battery module (300). Therefore, it is reasonable to arrange the plurality of support members (540) such that the length or bending angle increases as they get closer to the central portion (A) of the pack case (100). By arranging the support portion (540A) closer to the center (A) of the pack case (100) to have a larger length or bending angle and arranging the support portion (540B) at a portion (B) further from the center to have a smaller length or bending angle, a design that takes into account the amount of expansion of the pack lid (140) is possible, and accordingly, the elastic portion (500) can stably support the pack lid (140). According to the different design methods of the support portions (540) at the center (A) and the portion (B) further from the center of the pack case (100), the elastic portion (500) can be supported in a balanced manner on the pack lid (140), and thus the pressure applied to the module cover (320) is also maintained in a balanced manner, so that the module (300) can be effectively prevented from being lifted even in high temperature or high pressure situations, and the spread of gas or flame to adjacent cells or modules (300) can also be minimized or delayed.

[0074] The base portion (520) of the elastic portion (500) is provided in a grid shape spaced apart from each other as shown in FIG. 2, and is composed of a plurality of first frames (522) that cross the battery module (300) in the width direction and a plurality of second frames (524) that extend in a direction intersecting the first frames (522) to form a grid shape. The support portion (540) is formed by cutting a part of the base portion (520) and bending it toward the pack case (100), and a part of the second frame (524) can be bent toward the pack case (100) to form the support portion (540). Either one end or the other end of the second frame (524) of the base portion (520) is bent to form the support portion (542), and the support portions (542) on a pair of adjacent second frames (524) can be formed such that their respective ends are alternately misaligned as shown.

[0075] Since the elastic member (500) receives the pressing force from the pack case (100) through the support member (540) and transmits it to the battery module (300) through the base member (520), it is important that the plurality of supporting members (540) within the elastic member (500) are supported by the pack case (100) in a balanced manner. Accordingly, the present invention forms the supporting members (542) by alternately misaligning one end and the other end of the second frame (524) as shown in FIG. 2, thereby achieving a balance between the supporting force from the pack case (100) and the pressing force to the module cover (320), and as a result, the battery module (300) can be prevented from being lifted in high temperature or high pressure situations.

[0076] Specifically, in the case of the one-end support portion (542) of the second frame (524), since it is supported on the left side of the pack case (100), the pressing force is transmitted to the right side of the base portion (520), thereby pressing the module cover (320), and in the case of the other-end support portion (542) of the second frame (524), since it is supported on the right side of the pack case (100), the pressing force is transmitted to the left side of the base portion (520), thereby pressing the module cover (320). In this way, by alternately displacing one end and the other end of the second frame (524) to form a support portion (542), the elastic portion (500) can be supported evenly on the pack case (100) and at the same time, the module cover (320) can be stably pressed, thereby preventing the battery module (300) from being lifted even in the event of thermal runaway, and this battery system can also help improve the safety of the entire battery pack (BP).

[0077] In contrast, in the case of the outermost ends (544) of a plurality of second frames (524), the support portions (542) are not formed by being alternately misaligned, but rather, as shown in FIG. 2, all the outermost ends of the second frames (524) are bent to form the support portions (544). In the case of the outermost ends (544) of the second frames (524), they must be more stably supported by the pack case (100) and effectively transmit the pressing force to the center of the base portion (520). Therefore, unlike the support portions (542) of one and the other ends of the second frames (524) that are alternately misaligned, all the ends are bent to be supported by the pack case (100). Accordingly, the elastic member (500) can effectively transmit the pressing force obtained from the packing case (100) to the central part of the base part (520) by bending all the outermost ends (544) at both ends of the second frame (524) so ​​as to be supported by the pack case (100), and the battery module (300) can be sufficiently pressed by the base part (520), and the pressing force can prevent the battery module (300) from being lifted during thermal runaway, thereby preventing or delaying the spread of gas or flame to adjacent battery cells or battery modules (300).

[0078] Meanwhile, the battery system according to the present invention can be applied to battery packs (BP) of various vehicles (V) such as internal combustion engine vehicles, electric vehicles, hybrid vehicles, and fuel cell vehicles, as shown in FIG. 8, and in addition to vehicles (V), it can be applied to battery packs (BP) in various fields such as industrial ESS (Energy Storage System), household ESS, and small battery packs.

[0079] Although the present invention has been illustrated and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that the present invention may be variously improved and modified without departing from the technical spirit of the invention as defined by the following claims.

Claims

1. A battery module with a vent formed on one side; A pack case with the battery module installed inside; and A battery system comprising an elastic member provided on one side of the battery module, positioned at a point that does not overlap with the venting portion, and supported by protruding a portion toward the pack case, thereby pressing one side of the battery module with respect to the pack case.

2. In claim 1, The above venting portion is provided in multiple numbers spaced apart on one side of the battery module, and the elastic portion is positioned between the plurality of venting portions in a grid shape. A battery system characterized in that the outermost venting portion among the plurality of venting portions formed on one side of the battery module is provided adjacent to the edge of the battery module, and the elastic portion is provided at a point inside the outermost venting portion.

3. In claim 1, A battery system characterized in that the elastic portion is composed of a base portion and a support portion, and the support portion is supported by the pack case by bending a portion of the base portion in a direction toward the pack case.

4. In claim 3, An insulating portion is provided in the above elastic portion, and the insulating portion is formed of a fire-resistant material and is placed between the base portion and the battery module. A battery system characterized in that the insulating portion of the elastic portion is in close contact with one surface of the battery module, and the end of the supporting portion is supported on the inner surface of the pack case.

5. In claim 3, A battery system characterized in that the base portion of the elastic portion is made of a metal material, and the support portion is formed integrally with the base portion.

6. In claim 3, The base portion of the elastic portion is provided with a bead formed to protrude along the direction in which the base portion extends. The above bead is formed on the base portion and is provided to extend to the support portion, A battery system characterized in that the above beads are formed to protrude in a direction toward the pack case.

7. In claim 3, A battery system characterized in that the support portion of the elastic portion is pressurized by the pack case when the pack case is not expanded, thereby forming a preload toward the battery module.

8. In claim 3, A battery system characterized in that when the pack case expands, the support portion of the elastic member maintains support for the pack case and the angle of bending toward the pack case increases.

9. In claim 3, The support portion of the elastic portion is supported by an elastic body on one side of the battery module, A battery system characterized in that the elastic body is stretched when the pack case expands, and the support part is elastically supported toward the pack case by the elastic body.

10. In claim 3, A battery system characterized in that the support portion of the elastic portion is provided in multiple numbers, and the length or bending angle of the multiple support portions increases as they approach the central portion of the pack case.

11. In claim 3, The base portion of the elastic portion is formed of a plurality of first frames spaced apart from each other and extending across the battery module in the width direction, a plurality of second frames extending in a direction intersecting the first frames and connecting the first frames, and a part of the second frame is bent toward the pack case to form the support portion. A battery system characterized in that the second frame has one or both ends bent to form the support portion, and the pair of adjacent second frames have the support portions formed with the ends thereof misaligned from each other.

12. In claim 11, A battery system characterized in that the outermost second frames among a plurality of second frames are arranged such that the outermost ends are all bent to form the support portion.

13. In claim 1, A battery system characterized in that the pack case has one side open, the open side is closed through a pack lid, and the elastic part is provided between the pack lid and the battery module.

14. In claim 1, A battery system characterized in that a module cover having a plurality of venting portions formed on one side of the battery module is provided, and the elastic portion is positioned at a point avoiding the venting portion between the pack case and the module cover.

15. A vehicle characterized by including the battery system of claim 1.

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