Battery systems and vehicles containing them

Abstract

A battery system and a vehicle including the same are disclosed, which include a battery module having a venting section formed on one surface, a pack case in which the battery module is installed, and a biasing section provided on one surface of the battery module, positioned at a point that does not overlap with the venting section, and supported by a portion of which protruding toward the pack case, thereby pressurizing one surface of the battery module relative to the pack case.

Description

Technical Field

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

Background Art

[0002] Recently, technologies for carbon reduction have been actively developed to solve environmental problems such as abnormal temperatures. In order to reduce carbon, energy must be produced in an environmentally friendly way instead of producing energy with fossil fuels, and the produced energy must be stored in the form of electrical energy, and the stored electrical energy must be used in vehicles, various industrial sites, and homes.

[0003] In order to utilize electrical energy for carbon reduction, it is essential to use a battery that can store and draw out electrical energy. Therefore, ensuring the performance of the battery is essential in order to sufficiently store electrical energy and use it without inconvenience.

[0004] Batteries mainly utilize the redox reaction of metal ions, and in order to increase the capacity, charge-discharge performance, and efficiency of the battery, metal ions are used at high density, and many studies have been made on substances constituting the electrolyte and solid electrolytes. However, generally, there is a problem that the stability decreases as the performance of the battery develops.

[0005] In the case of batteries used in vehicles, industries, homes, etc., they are manufactured in a physical unit called a pack. The battery pack houses a large number of battery cells inside a battery case and seals them, preventing the transfer of fire to the outside even in case of an accident such as thermal runaway of the battery, and protecting the internal battery cells from deterioration due to the influence of the external environment or damage for physical reasons.

[0006] A battery pack contains numerous battery cells in a form intermediate between modules and assemblies (CMAs, Cell module assemblies). In the case of battery modules or assemblies, numerous battery cells are assembled into a single module or assembly, and these modules are fastened together inside the pack case, completing the battery pack. During battery maintenance, maintenance is made easier by performing maintenance on these module or assembly units.

[0007] The numerous unit battery cells that make up a module or assembly consist of a positive electrode, a negative electrode, and an electrolyte. Since battery cells generate heat during charging and discharging, effective heat dissipation is necessary. Furthermore, from the perspective of battery modules, assemblies, and battery packs, efficient heat dissipation design is essential to prevent safety accidents.

[0008] On the other hand, batteries can deteriorate due to manufacturing errors, excessive charging and discharging, and aging. If battery deterioration continues, it can eventually lead to a fire. Therefore, it is necessary to take precautions to prevent fires from occurring due to batteries. To this end, it is important to continuously sense the battery's condition and to recognize and respond to any problems in advance, so that damage can be minimized in the event of an unexpected problem.

[0009] In particular, if a flame occurs in a specific cell of a specific module among the many battery modules inside a battery pack, it is necessary to prevent the flame from spreading to other adjacent battery cells, and also to prevent the flame from spreading to other adjacent modules. Therefore, from the perspective of the battery module, gas venting from the problematic battery cell must be smooth, while at the same time, the vented gas or flame must be prevented or delayed as much as possible from affecting other cells or modules.

[0010] The matters described above as background technology are intended to enhance understanding of the background of the present invention and should not be interpreted as constituting prior art already known to those with ordinary skill in this field. [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] This invention was proposed to solve these problems and aims to provide a battery system and a vehicle including it that can improve battery safety by preventing flame propagation to adjacent cells or modules in the event of a fire in a specific battery cell or battery module, while still allowing for smooth gas venting.

[0012] The technical problems that this invention aims to solve are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those with ordinary skill in the art to which this invention pertains from the description below. [Means for solving the problem]

[0013] To achieve the above objective, the battery system according to the present invention includes a battery module having a venting portion formed on one surface, a pack case in which the battery module is installed, and a biasing portion provided on one surface of the battery module, positioned at a location that does not overlap with the venting portion, and supported by a portion that protrudes toward the pack case, thereby pressurizing one surface of the battery module with respect to the pack case.

[0014] In the battery system according to the present invention, multiple venting sections are provided spaced apart on one surface of the battery module, and the biasing section may be positioned between the multiple venting sections in a grid shape.

[0015] In the battery system according to the present invention, of the multiple venting sections formed on one surface of the battery module, the outermost venting section is provided adjacent to the frame of the battery module, and the biasing section may be provided at a point inside the outermost venting section.

[0016] In the battery system according to the present invention, the biasing portion consists 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 toward the pack case.

[0017] In the battery system according to the present invention, an insulating portion is provided in the biasing portion, the insulating portion is made of a fire-resistant material, and can be placed between the base portion and the battery module.

[0018] In the battery system according to the present invention, the insulating portion of the biasing portion is in close contact with one surface of the battery module, and the end of the support portion can be supported on the inner surface of the pack case.

[0019] In the battery system according to the present invention, the base portion of the biasing part is made of metal, and the support portion can be formed integrally with the base portion.

[0020] In the battery system according to the present invention, the base portion of the biasing portion may be provided with a bead that protrudes along the direction in which the base portion extends.

[0021] In the battery system according to the present invention, the bead may be formed on the base portion and extend to the support portion.

[0022] In the battery system according to the present invention, the bead may be formed to protrude in the direction of the pack case.

[0023] In the battery system according to the present invention, the support portion of the biasing portion can be pressurized by the pack case when the pack case is not expanded, thereby forming a pre-pressure toward the battery module.

[0024] In the case of the battery system according to the present invention, when the pack case expands, the support portion of the biasing portion is maintained in support on the pack case, and the angle bent toward the pack case can be increased.

[0025] In the case of the battery system according to the present invention, the support portion of the biasing portion can be supported by a biasing body on one surface of the battery module.

[0026] In the case of the battery system according to the present invention, the biasing body is extended when the pack case expands, and the support portion can be biased and supported toward the pack case side by the biasing body.

[0027] In the case of the battery system according to the present invention, a plurality of support portions of the biasing portion are provided, and the closer the plurality of support portions are adjacent to the central portion of the pack case, the greater the length or the bent angle can be.

[0028] In the case of the battery system according to the present invention, the base portions of the biasing portions are spaced apart from each other, and are composed of a plurality of first frames crossing the battery module in the width direction and 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 can be bent toward the pack case to form a support portion.

[0029] In the case of the battery system according to the present invention, one of either the one end or the other end of the second frame is bent to form a support portion, and a pair of adjacent second frames can be formed such that the support portions are offset from each other at one end and the other end.

[0030] In the case of the battery system according to the present invention, among the plurality of second frames, the second frame disposed on the outermost periphery can form a support portion by bending all the ends of the outermost periphery.

[0031] In the case of the battery system according to the present invention, one surface of the pack case is open, the open surface is closed through a pack lead, and the biasing portion can be provided between the pack lead and the battery module.

[0032] In the battery system according to the present invention, a module cover with a plurality of venting sections is provided on one side of the battery module, and the biasing section may be positioned between the pack case and the module cover at a point that avoids the venting sections.

[0033] In the case of a vehicle according to the present invention, the battery system is as described above. [Effects of the Invention]

[0034] The battery system and vehicle incorporating the present invention can prevent the spread of flames to other adjacent cells or modules in the event of a fire in a specific battery cell or module, and at the same time facilitate gas venting in the problematic battery cell or module, thereby improving the overall safety of the battery system and the higher-level systems that utilize it.

[0035] The effects obtained by the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those with ordinary skill in the art to which the present invention pertains from the description below. [Brief explanation of the drawing]

[0036] [Figure 1] This is a drawing showing a battery system according to one embodiment of the present invention. [Figure 2] Figure 1 is a diagram showing the biasing mechanism of the battery system. [Figure 3] This diagram shows a cross-section of the battery system shown in Figure 2, obtained by cutting along the A-A' line. [Figure 4] This is a diagram showing a cross-section of the battery system of the present invention with and without expansion of the pack case. [Figure 5] This drawing shows a case where the biasing portion of the battery system of the present invention is provided on the side of the battery module. [Figure 6]This is a diagram showing a cross-section of a battery system according to another embodiment of the present invention, depending on whether or not the pack case is expanded. [Figure 7] This is a drawing illustrating the differences in location-specific biasing units in a battery system according to one embodiment of the present invention. [Figure 8] This is a drawing showing a battery pack and a vehicle to which the battery system of the present invention is applied. [Modes for carrying out the invention]

[0037] In describing the embodiments disclosed herein, if a specific description of related published technology is deemed to obscure the gist of the embodiments disclosed herein, such detailed description will be omitted. Furthermore, the accompanying drawings are provided solely to facilitate understanding of the embodiments disclosed herein, and it should be understood that the accompanying drawings do not limit the technical ideas disclosed herein and include all modifications, equivalents, or substitutions that fall within the concept and technical scope of the present invention.

[0038] Terms including ordinal numbers, such as "first," "second," etc., can be used to describe a variety of components, but the components are not limited by such terms. These terms are used solely for the purpose of distinguishing one component from others. A singular expression includes plural expressions unless the context clearly indicates otherwise.

[0039] In this specification, terms such as “includes” or “having” are intended to specify the existence of features, figures, stages, operations, components, parts, or combinations thereof described in the specification, and should not be understood to preemptively exclude the existence or possibility of adding one or more other features, figures, stages, operations, components, parts, or combinations thereof. The suffixes “module” and “part” used for components in the following description are added or used interchangeably solely for the sake of ease of specification preparation and do not have any distinct meaning or role in themselves.

[0040] When it is mentioned that one component is "connected" to or "linked" to another component, it should be understood that it may be directly connected to or linked to the other component, but that other components may also exist in between. Conversely, when it is mentioned that one component is "directly connected" to or "directly linked" to another component, it must be understood that there are no other components in between.

[0041] The embodiments disclosed herein will now be described in detail with reference to the attached drawings. Regardless of the reference numerals in the drawings, identical or similar components will be given the same reference numerals, and redundant descriptions will be omitted. A battery consists of multiple battery cells that make up a battery module 300, and multiple battery modules 300 make up a battery pack BP. Batteries are subjected to stress due to design or manufacturing defects, excessive charging or discharging, misuse or abuse, etc. If such stress persists, the battery cells deteriorate. When a battery cell deteriorates and is kept above a certain temperature, the flammable electrolyte inside the battery cell vaporizes and is ejected, increasing the pressure inside the cell and causing a fire to occur inside the battery cell. This immediately leads to a fire in an adjacent battery cell, and the fire between cells spreads to the battery modules 300, causing a thermal runaway phenomenon. When a battery cell or battery module 300 experiences such a thermal runaway, it is important to prevent or delay the propagation of gas and flame to adjacent cells or modules 300, while simultaneously ensuring smooth gas discharge in the desired direction.

[0042] The present invention aims to improve the performance and safety of a battery pack BP by preventing one side of the battery module 300 from lifting due to high temperature or high pressure during thermal runaway caused by a fire in a battery cell or battery module 300, and by preventing the propagation of gas or flames to adjacent cells or modules 300 while allowing smooth gas venting inside the cell or module 300 where thermal runaway has occurred.

[0043] Specifically, the battery module 300 of the present invention includes a module cover 320 as shown in Figure 1. The module cover 320 is attached to one side of the battery cell to protect the battery module 300 and the battery cell from gases and flames in the adjacent battery cell and the battery module 300, and one side of the module cover 320 includes a venting section 340 for smoothly venting gases and flames generated when the battery cell inside the battery module 300 experiences thermal runaway.

[0044] Furthermore, the module cover 320 may be molded from a heat-resistant and insulating material such as mica to prevent gases and flames generated by thermal runaway in adjacent battery cells or the battery module 300 from spreading to those cells or modules 300. In Figure 1, the module cover 320 is located at the top of the battery cell to protect it. The module cover 320 is not necessarily limited to the illustrated embodiment in order to perform its role of protecting the cell and module 300, and can 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.

[0045] On the other hand, the battery module 300 has a venting section 340 that can discharge gases and flames generated during thermal runaway in the battery cells and the battery module 300. Referring to Figure 1, the venting section 340 is formed in the module cover 320 of the battery module 300, and if the venting section 340 is removed, a venting hole is formed. The venting hole is formed on the outer surface of the battery module 300 and plays the role of discharging gases and flames caused by thermal runaway generated inside the module 300, and there may be multiple venting holes to ensure smooth discharge of gases and flames. In addition, the venting hole must be able to vent smoothly during thermal runaway in the cell or module 300 in question, but the module cover 320 must protect the cells inside during thermal runaway in adjacent cells or modules 300, so the venting section 340 has a shape that is partially cut out in the module cover 320. In other words, in the case of a venting hole, under normal conditions it is sealed by the venting section 340 to protect the cells inside the module 300, and only when high temperature or high pressure conditions are the partially cut venting section 340 fully cut and opened to the venting hole for the discharge of gas or flames. Furthermore, if the module cover 320 adequately protects the internal cells and module 300 under normal conditions and is opened only when necessary, then various types of venting sections 340, such as adhesive or fitting, can be applied to the module cover 320, not just partial cuts.

[0046] On the other hand, superior battery performance means that the battery has a high energy density. A battery pack BP is composed of multiple battery modules 300, and since such modules 300 are formed by combining multiple battery cells, stacking the battery cells densely is a way to increase the energy density of the battery itself. Therefore, in order to achieve excellent battery performance, the battery module 300 must have as many battery cells as possible stacked at a high density.

[0047] The venting section 340 is for the discharge of gases and flames generated when battery cells experience thermal runaway. It is formed on the outer surface of the battery module 300 or module cover 320 and is located in a position corresponding to where battery cells are located inside the module 300. In addition, to ensure excellent battery performance, the battery module 300 is stacked with the maximum number of battery cells at a high density, and as a result, battery cells are arranged inside the battery module 300 all the way to the outermost part. Therefore, in the case of module 300 or module cover 320, a venting section 340a is also provided on the outermost part of module 300 or module cover 320, as shown in Figure 1, to facilitate the venting of gases or flames generated when battery cells located in the outermost part experience thermal runaway.

[0048] In the present invention, a biasing portion 500 is provided on one side of the battery module 300 and positioned at a location not overlapping with the venting portion 340 to pressurize the module 300 and prevent the module 300 from floating up. The biasing portion 500 is made of a heat-resistant metal material and can pressurize the battery module 300 without any change in physical properties even in high-temperature environments due to thermal runaway. Furthermore, by including a fire-resistant insulating portion 560 in the configuration that performs the pressurization, an electrical short circuit between the battery module 300 and the pack case 100 can also be prevented.

[0049] Specifically, the present invention presents a battery system in which a biasing portion 500 is located between a pack case 100 and a battery module 300, the biasing portion 500 is positioned on one side of the battery module 300 in a space that does not overlap with the venting portion 340, and a portion of the biasing portion 500 is supported protruding toward the pack case 100.

[0050] In this invention, the battery module 300 includes a module cover 320, and a plurality of venting sections 340 are formed on the outer surface of the module 300 or module cover 320, spaced apart from each other. The venting sections 340 include venting holes, through which gas and flames are discharged to the outside in the event of thermal runaway of the battery cells. The biasing section 500 is positioned in a grid shape as shown in Figure 1 on one surface of the module 300 at points that avoid the venting sections 340. Through the biasing section 500 arranged in such a grid shape, the discharge of gas and flames from the venting sections 340 becomes smoother, preventing the battery module 300 or module cover 320 from lifting due to high temperature or high pressure, and effectively preventing the propagation of gas and flames to adjacent cells or modules 300.

[0051] To improve battery performance, battery cells are stacked at a high density inside the battery module 300. The venting section 340 located on one side of the module 300 is for facilitating the discharge of gases and flames when the cells inside the module 300 experience thermal runaway, and must be formed in a location corresponding to where the cells are arranged on one side of the module 300. Therefore, a venting section 340a is also formed on the outermost part of the module 300 to discharge gases and flames generated when the densely stacked battery cells experience thermal runaway.

[0052] Since the outermost venting section 340a is formed adjacent to the frame of the battery module 300, the biasing section 500 is provided inside the module 300 or module cover 320 with respect to the outermost venting section 340a, and is arranged in a grid-like configuration between the multiple venting sections 340 located on the inside. Because the biasing section 500 is positioned at a location that avoids the venting sections 340 through its grid-like arrangement, venting of gases and flames generated during thermal runaway is possible smoothly, and at the same time, the battery module 300 can be effectively pressurized. Furthermore, since the biasing section 500 is provided inside the outermost venting section 340a, the battery cells inside the module 300 can be stacked with density, which can contribute to improving overall battery performance.

[0053] The biasing section 500 consists of a base section 520 and a support section 540, where a part of the base section 520 is bent toward the pack case 100 and supported by the pack case 100. The biasing section 500 is made of a metal material that can withstand high temperature or high pressure environments caused by thermal runaway in the battery cell or battery module 300, and the support section 540 is formed by bending a part of the base section 520 and can be molded integrally with the base section 520. The biasing section 500 can be formed by manufacturing the metal base section 520 in a grid pattern using a press punching method, then cutting a part of the base section 520 to form the support section 540, and finally bending the cut portion. Since the base section 520 and the support section 540 are integrally formed in the biasing section 500, the support section 540 can effectively transmit the pressurizing force received from the pack case 100 to the base section 520, thereby allowing the battery module 300 to be sufficiently pressurized.

[0054] Furthermore, the biasing section 500 includes an insulating section 560. The base section 520 and support section 540 of the biasing section 500 are made of a metallic conductor and therefore have excellent electrical conductivity. If insulation is not provided when using such a conductor, an electrical short circuit will occur inside the pack case 100, and a large current will flow through the conductor when an electrical short circuit occurs, which may cause the battery and conductor to deteriorate or catch fire, resulting in secondary damage. Therefore, the biasing section 500 must include an insulating section 560 in addition to the base section 520 and support section 540, and the insulating section 560 is located between the base section 520 and the battery module 300 and plays a role in preventing an electrical short circuit between the module 300 and the pack case 100. In addition, since the insulating section 560 must perform its insulating function even in high-temperature environments due to thermal runaway of the battery cells and battery module 300, it can be made of a fire-resistant material such as mica. Of course, the battery system of the present invention is not limited to the materials and shapes presented above.

[0055] On the other hand, the base portion 520 of the biasing portion 500 is provided with a bead 580 that protrudes along the direction in which the base portion 520 extends, as shown in Figure 2. In the case of the biasing portion 500, it includes a base portion 520 made of metal, and the metal base portion 520 may undergo physical deformation such as twisting or bending in the high temperature or high pressure environment that occurs when the battery cell or battery module 300 experiences thermal runaway. If the base portion 520 is physically deformed by gas or flames caused by thermal runaway, the battery module 300 will not be able to be sufficiently pressurized, causing the module 300 to lift up, which facilitates the propagation of gas or flames to adjacent cells or modules 300.

[0056] Therefore, to prevent deformation of the base portion 520, a bead 580 can be formed so that the central portion of the base portion 520 protrudes, as shown in Figures 2 and 3. The bead 580 can be integrally molded to protrude from the base portion 520 during the lattice-shaped molding process of the biasing portion 500, and can be molded from the same material as the base portion 520. By forming a bead 580 on the base portion 520, the biasing portion 500 can sufficiently pressurize the battery module 300 without the base portion 520 easily deforming even in high temperature and high pressure environments due to thermal runaway. Furthermore, as shown in Figure 2, the bead 580 is formed on one surface of the second frame 524 along the direction in which the base portion 520 extends, and it goes without saying that it may also be present on one surface of the first frame 522 that intersects with the second frame 524.

[0057] Furthermore, the bead 580 can be molded to protrude from the base portion 520 toward the pack case 100, as shown in Figure 3, or it can be molded to protrude in the opposite direction toward the battery module 300, or it can be molded to protrude in both directions. Since the support portion 540 of the biasing portion 500 can be molded 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 it extends to the support portion 540, the cross-section of the support portion 540 will have a shape in which the protruding bead 580 is formed, as shown in Figure 3, and it can be bent toward the pack case 100 or the battery module 300 in this shape.

[0058] In the case of the biasing unit 500, as shown in Figure 4, it is installed between the pack case 100 and the battery module 300, the insulating part 560 of the biasing unit 500 is in close contact with one surface of the battery module 300, and the end of the support part 540 of the biasing unit 500 is supported and fixed to the inner surface of the pack case 100.

[0059] In the battery system of the present invention, the pack case 100 consists of a case body 120 and pack leads 140, and the battery module 300 includes a module cover 320. Therefore, the biasing portion 500 is located between the pack leads 140 and the module cover 320 as shown in Figure 4, or formed between the case body 120 and the battery module 300 as shown in Figure 5. In this case, the insulating portion 560 of the biasing portion 500 is in close contact with one surface of the module cover 320 or the module 300, and the support portion 540 of the biasing portion 500 can be fixed by having its end supported on the inner surface of the pack leads 140 or the case body 120.

[0060] Specifically, before the pack case 100 expands, the support portion 540 of the biasing portion 500 is pressurized by the pack case 100 toward the battery module 300, maintaining a state where pre-pressure is formed. Since the biasing portion 500 is made of metal and has restorative force, when the pack case 100 pressurizes the biasing portion 500 toward the battery module 300, it can maintain a state in which the biasing force is stored. Subsequently, if thermal runaway occurs in the battery cells or battery module 300, the pack case 100 will expand due to high-pressure gas or high-temperature flames, as shown by the solid line portion of Figure 4. In the present invention, when the pack case 100 expands due to thermal runaway, the biasing force stored in the biasing portion 500, which had pre-pressure formed, will come into effect. Therefore, even during thermal runaway, the support portion 540 of the biasing portion 500 still maintains support to the pack case 100, and the support portion 540 being supported by the pack case 100 allows for continuous pressurization of the module cover 320, thus preventing the module cover 320 from lifting up at the upper end of the battery module 300. If the module cover 320 were to lift up due to flames or gases, gases or flames would be ejected between the module cover 320 and the upper end of the module 300, which would mean the ejection of gases and flames in an unintended direction. This could then lead to the propagation of flames to other adjacent modules 300 or cells. Therefore, by ensuring that the module cover 320 stably pressurizes the upper end of the module 300 and prevents it from lifting up, as in the present invention, the propagation of gases and flames to adjacent cells and modules 300 can be minimized or delayed over time.

[0061] Figure 6 is a drawing showing a biasing section 500 according to another embodiment of the present invention. In this case, the support section 540 of the biasing section 500 is supported by a biasing body 590 located on one surface of the battery module 300. The biasing body 590 is positioned between the support section 540 of the biasing section 500 and the battery module 300. Before the pack case 100 expands, the pack case 100 pressurizes the support section 540 toward the battery module 300, as shown by the dotted line in Figure 6, so that the biasing body 590 remains in a contracted state. If the pack case 100 expands due to thermal runaway in the battery cells or battery module 300, not only the support section 540 but also the biasing body 590 will expand together, as shown by the solid line in Figure 6. The support section 540 is then biased and supported by the biasing body 590, allowing it to maintain a more robust support for the pack case 100. In this case, the biasing body 590 is provided with a metal spring or the like that can withstand high temperature or high pressure conditions, and in some cases multiple units may be required. When using a metal biasing body 590, an insulating part 560 must be provided between the biasing unit 500 and the battery module 300 to ensure insulation between the pack case 100 and the battery module 300. By adding the additional biasing body 590 to the biasing unit 500 in this way, the support force of the biasing unit 500 can be increased. When multiple biasing units 500 are applied to one module 300, it is possible to create differences in the biasing force between the biasing units 500 by applying the biasing body 590 to only some of the biasing units 500.

[0062] The pack case 100 may consist of a case body 120 and a pack lead 140 for ease of assembly. The case body 120 has an open side, and the pack lead 140 performs the function of closing the open side of the case body 120. As shown in Figure 1, when the case body 120 has an open top, the bottom and side walls form an internal space, and the battery module 300 is mounted inside through the top. The pack lead 140 then protects the battery module 300 by closing the top of the case body 120.

[0063] In the case of a battery installed in a vehicle V, performance against collisions must be ensured, and secondary damage must be prevented in the event of a fire; therefore, the pack case 100 can be made of metal. Among metals, it can be made of aluminum, which is easy to mold, lightweight, and highly durable. In the case of a pack case 100 made of metal such as aluminum, thermal deformation due to expansion may occur in high temperature or high pressure environments due to thermal runaway in some battery cells or battery modules 300. The gap between the expanded pack leads 140 and the module cover 320 widens due to such thermal deformation, increasing the lifting phenomenon of the module cover 320 at the relevant point, and the amount of expansion of the pack leads 140 can vary from point to point even within a single pack case 100. Therefore, the biasing portion 500 of the present invention also needs to be formed differently at different points to support the module cover 320.

[0064] Referring to Figure 7, in the case of the outer part B of the pack case 100, which is far from the center, the amount of expansion is relatively smaller compared to the central part A. In the case of the outer part B of the case body 120, the bottom surface and side walls are molded into a housing shape in which they are integrally formed, and in the case of the outer part B of the pack lead 140, it is connected to the case body 120 by various methods such as welding, bonding, and mechanical fastening. Therefore, even if thermal runaway occurs in some battery cells or battery modules 300, there is a limit to the amount of expansion in the outer part B of the pack case 100. On the other hand, in the case of the central part A of the pack case 100, the case body 120 has a wide surface shape for mounting the battery modules 300, and the pack lead 140 is also not directly connected to the case body 120, so it is the point where the amount of expansion is greatest when thermal runaway occurs. In other words, when thermal runaway occurs, the pack lead 140 expands more the closer it is to the central part A.

[0065] Multiple support sections 540 of the biasing section 500 are provided between the pack case 100 and the battery module 300. Considering that the amount of expansion of the pack lead 140 differs at different points, it is important to select different support sections 540 at different points to provide balanced support for the expanded pack lead 140 when the pack lead 140 expands due to thermal runaway in the battery cells or battery module 300. Therefore, it is appropriate to arrange the multiple support sections 540 so that the length or bending angle increases the closer they are to the central part A of the pack case 100. By arranging support sections 540A that are closer to the central part A of the pack case 100 with a larger length or bending angle, and support sections 540B in parts B further from the center with a smaller length or bending angle, it is possible to design the system while considering the amount of expansion of the pack lead 140, thereby enabling the biasing section 500 to stably support the pack lead 140. This design of different support sections 540 in the central part A and the part B away from the central part of the pack case 100 ensures that the biasing section 500 is supported evenly by the pack lead 140. As a result, the pressure applied to the module cover 320 is also maintained in a balanced manner, effectively preventing the module 300 from floating up even under high temperature or high pressure conditions, and minimizing or delaying the propagation of gas and flames to adjacent cells and modules 300.

[0066] The base portion 520 of the biasing portion 500 is provided in a grid shape with mutually spaced intervals, as shown in Figure 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 and 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 may be bent toward the pack case 100 to form the support portion 540. The second frame 524 of the base portion 520 has one end or the other end bent to form a support portion 542, and the support portions 542 on an adjacent pair of second frames 524 may be formed with their respective ends alternately offset from each other as shown in the figure.

[0067] In the biasing section 500, the support section 540 receives the pressurizing force from the pack case 100 and transmits it to the battery module 300 through the base section 520. Therefore, it is important that the multiple support sections 540 within the biasing section 500 are supported by the pack case 100 in a balanced manner. Accordingly, in the present invention, as shown in Figure 2, by forming the support sections 542 so that one end and the other end of the second frame 524 are alternately offset from each other, it is possible to maintain a balance between the support force from the pack case 100 and the pressurizing force applied to the module cover 320, and as a result, it becomes possible to prevent the battery module 300 from floating up under high temperature or high pressure conditions.

[0068] Specifically, in the case of the support portion 542 at one end of the second frame 524, it is supported on the left side of the pack case 100, thereby transmitting pressure to the right side of the base portion 520 and pressurizing the module cover 320. In the case of the support portion 542 at the other end of the second frame 524, it is supported on the right side of the pack case 100, thereby transmitting pressure to the left side of the base portion 520 and pressurizing the module cover 320. By arranging the support portions 542 by alternately offsetting one end and the other end of the second frame 524 in this way, the biasing portion 500 can be supported in a balanced manner on the pack case 100, and at the same time, the module cover 320 can be stably pressurized, preventing the battery module 300 from floating up even in the event of thermal runaway, and thus contributing to the improvement of the overall safety of the battery pack BP through such a battery system.

[0069] In contrast, in the case of the outermost ends 544 of multiple second frames 524, instead of configuring the support portions 542 so that they are alternately offset from one another, all the ends on the outermost edges of both ends of the second frame 524 are bent to form the support portions 544, as shown in Figure 2. In the case of the outermost ends 544 of both ends of the second frame 524, they must be more stably supported by the pack case 100 and effectively transmit the pressurizing force to the central part of the base portion 520. Therefore, unlike the support portions 542 of one end and the other end of the second frame 524, which are formed to be alternately offset, all the ends are bent and supported by the pack case 100. Therefore, the biasing section 500 bends all of the outermost ends 544 at both ends of the second frame 524 so that they are supported by the pack case 100, thereby effectively transmitting the pressurizing force obtained from the pack case 100 to the central part of the base section 520. This allows the base section 520 to sufficiently pressurize the battery module 300, and such pressurizing force prevents the battery module 300 from floating up during thermal runaway, thereby preventing or delaying the propagation of gas and flames to adjacent battery cells and battery modules 300.

[0070] On the other hand, 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 Figure 8. In addition to vehicles V, it can also be applied to battery packs BP in various fields, such as industrial ESS (Energy Storage Systems), household ESS, and small battery packs.

[0071] Although illustrated and described in relation to specific embodiments of the present invention, it will be obvious to those ordinary in the art that the present invention can be improved and modified in various ways without departing from the technical spirit of the invention provided by the following claims.

Claims

1. A battery module with vents formed on one side. A pack case in which the battery module is installed inside, and A biasing portion is provided on one surface of the battery module, positioned at a location not overlapping with the venting portion, and supported with a portion protruding toward the pack case, thereby applying pressure to one surface of the battery module with respect to the pack case. A battery system, including the battery system.

2. Multiple venting sections are provided spaced apart on one surface of the battery module, and the biasing section is positioned between the multiple venting sections in a grid shape. The battery system according to claim 1, characterized in that, of the plurality of venting portions formed on one surface of the battery module, the outermost venting portion is provided adjacent to the frame of the battery module, and the biasing portion is provided at a point inside the outermost venting portion.

3. The battery system according to claim 1 or 2, characterized in that the biasing portion is composed of a base portion and a support portion, and the support portion is supported by the pack case with a part of the base portion bent in a direction toward the pack case.

4. The biasing portion is provided with an insulating portion, the insulating portion is made of a fire-resistant material, and is positioned between the base portion and the battery module. The battery system according to claim 3, characterized in that the insulating portion of the biasing portion is in close contact with one surface of the battery module, and the end of the support portion is supported on the inner surface of the pack case.

5. The battery system according to claim 3, characterized in that the base portion of the biasing portion is made of metal, and the support portion is formed integrally with the base portion.

6. The base portion of the biasing part is provided with a bead that protrudes along the direction in which the base portion extends. The bead is formed on the base portion and extends to the support portion. The battery system according to claim 3, characterized in that the bead is formed to protrude in a direction toward the pack case.

7. The battery system according to claim 3, characterized in that the support portion of the biasing portion is pressurized by the pack case when the pack case is not expanded, and a pre-pressure is formed toward the battery module.

8. The battery system according to claim 3, characterized in that when the pack case expands, the support portion of the biasing portion maintains support on the pack case and the angle at which it is bent toward the pack case increases.

9. The support portion of the biasing portion is supported by a biasing body on one surface of the battery module. The battery system according to claim 3, characterized in that the biasing member is extended when the pack case expands, and the support portion is biased and supported toward the pack case by the biasing member.

10. The battery system according to claim 3, characterized in that a plurality of support portions are provided for the biasing portion, and the length or bent angle of the plurality of support portions increases as they are adjacent to the center of the pack case.

11. The base portion of the biasing part is spaced apart from each other and consists of a plurality of first frames that span the battery module in the width direction and a plurality of second frames that extend in a direction intersecting the first frames and connecting the first frames, with a portion of the second frames bent toward the pack case to form the support portion. The battery system according to claim 3, characterized in that the second frame has one end or the other end bent to form the support portion, and a pair of adjacent second frames have the support portions formed offset from each other at one end and the other end of each.

12. The battery system according to claim 11, characterized in that, of the multiple second frames, the second frame positioned on the outermost periphery has all of its outermost ends bent to form the support portion.

13. The battery system according to claim 1, characterized in that one side of the pack case is open, the open side is closed through the pack lead, and the biasing portion is provided between the pack lead and the battery module.

14. The battery system according to claim 1, characterized in that a module cover having a plurality of venting portions formed on one side of the battery module is provided, and the biasing portion is positioned between the pack case and the module cover at a point that avoids the venting portions.

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

Images