Battery pack and vehicle including same

Abstract

A battery pack according to the present invention comprises: a battery unit; a pack tray which accommodates the battery unit, and includes a lower tray that supports the battery unit from below the battery unit; and a base plate configured to support the pack tray from below the pack tray, wherein the lower tray may include a plurality of ribs which protrude in a downward direction and upper surfaces of which are in direct contact with the battery unit.

Description

Battery pack and automobile including the same

[0001] The present invention relates to a battery pack and an automobile including the same.

[0002] This application is a priority application for Korean Patent Application No. 10-2025-0013832 filed on February 4, 2025, and all contents disclosed in the specification and drawings of said application are incorporated into this application by reference.

[0003]

[0004] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric sources. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0005] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. When a high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Additionally, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or battery pack. Therefore, the number of battery cells included in the battery module or pack can be varied depending on the required output voltage or charge / discharge capacity.

[0006] When configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first construct a battery module containing at least one battery cell, and then use this at least one battery module to add other components to form a battery pack or battery rack. Alternatively, recently, battery packs in the form of a "Cell-to-Pack," in which multiple battery cells are directly housed in a pack housing without modularization, are also being manufactured.

[0007] However, when multiple battery modules are contained within a battery pack in this manner, it can be vulnerable to thermal chain reactions between the modules. For example, if an event such as thermal runaway occurs within a single battery module, this runaway can propagate to other battery modules. If the propagation of thermal runaway between battery modules is not properly suppressed, an event originating in a specific module can trigger a chain reaction across multiple modules, potentially causing serious problems such as explosions or fires.

[0008] In this case, if a thermal event occurs within the battery module and high-temperature gases are released upward, there is a risk of harm to occupants of the vehicle or a chain reaction of problems affecting other vehicles. However, if high-temperature gases are released downward, heat conduction may be relatively easier due to the pack case in direct contact with the battery module. Therefore, compared to upward venting, downward venting increases the heat flux to adjacent battery modules, which may raise the risk of thermal runaway.

[0009] Therefore, there is a need to develop a battery pack case structure capable of slowing down the rate of heat transfer to adjacent battery modules, even when venting downwards occurs in the event of a thermal event in a battery cell.

[0010]

[0011] Therefore, the problem that the present invention aims to solve is to provide a battery pack capable of preventing the risk of direct damage to occupants of a vehicle or cascading damage to other vehicles by inducing downward venting when a thermal event occurs in a battery cell.

[0012] In addition, the invention provides a battery pack capable of preventing thermal runaway by preventing and / or minimizing heat transfer to adjacent battery cells when a thermal event occurs in a battery cell and reducing the heat flux to adjacent battery cells.

[0013] However, the problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below.

[0014]

[0015] To solve the above problem, the battery pack of the present invention comprises a battery unit, a pack tray for accommodating the battery unit, the pack tray having a lower tray that supports the battery unit from below the battery unit, and a base plate configured to support the pack tray from below the pack tray, wherein the lower tray may have a plurality of ribs that protrude in a downward direction and whose upper surface is in direct contact with the battery unit.

[0016] The battery unit may have a venting section configured to vent the venting gas downward when a thermal event occurs.

[0017] The above rib may face only one battery unit.

[0018] The above ribs may extend in the longitudinal direction of the battery unit, and a plurality of the above ribs may be spaced apart in the width direction of the battery unit.

[0019] The vertical length of the above rib may be 2mm or more and 10mm or less.

[0020] Heat generated in the battery unit is transferred vertically through the rib, and the heat transferred through the rib can be transferred horizontally through the base plate.

[0021] The above pack tray may be configured to be formed by a die-casting process.

[0022] The base plate may be positioned spaced apart from the lower tray and may be in contact with the lower surface of the rib.

[0023] The lower tray may further have at least one venting hole configured to be located between a plurality of adjacent ribs and to communicate with the venting portion.

[0024] A vertical venting channel is formed in the lower tray to transmit the venting gas introduced into the venting hole in a vertical direction, and the vertical venting channel may be surrounded by the lower tray, the base plate, and the ribs located on both sides of the vertical venting channel.

[0025] The lower tray may further have a recessed groove portion extending upward from the lower surface of the lower tray, and may be configured to discharge venting gas introduced through the vertical venting channel to the outside through a horizontal venting channel formed by the groove portion.

[0026] The above-mentioned groove may be positioned adjacent to the plurality of venting holes and formed to extend in the width direction of the battery unit.

[0027] The above horizontal venting channel may be surrounded by the above groove and the above base plate.

[0028] The battery pack may further include a cooling module located on the upper side of the battery unit.

[0029] The present invention can provide an automobile characterized by including at least one battery pack according to the present invention.

[0030]

[0031] According to one aspect of the present invention, a battery pack can be provided that induces downward venting when a thermal event occurs in a battery unit, thereby preventing the risk of direct damage to occupants of a vehicle or chain damage to other vehicles.

[0032] In addition, a battery pack can be provided that prevents and / or minimizes heat transfer to adjacent battery units when a thermal event occurs in a battery unit, and reduces the heat flux to adjacent battery units to prevent thermal runaway.

[0033] In addition, since ribs are directly implemented in the pack tray and the rib structure can be implemented simultaneously with the production of the pack tray, additional parts equipped with ribs can be omitted, thereby providing a battery pack that can reduce material costs.

[0034] In addition to the above, the present invention may have various other effects, which are described in each embodiment, or effects that can be easily inferred by those skilled in the art, etc., will be omitted.

[0035]

[0036] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0037] FIG. 1 is a perspective view of a battery pack according to one embodiment of the present invention, excluding the upper tray.

[0038] FIG. 2 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0039] FIG. 3 is a top view of a pack tray of a battery pack according to one embodiment of the present invention.

[0040] FIG. 4 is a cross-sectional view of the battery pack of FIG. 1 according to one embodiment of the present invention, cut along line A-A'.

[0041] Figure 5 is an enlarged view of part C of Figure 4.

[0042] FIG. 6 shows the heat conduction path of a battery pack according to one embodiment of the present invention.

[0043] FIG. 7 is a view of the pack tray of a battery pack according to one embodiment of the present invention, seen from the bottom.

[0044] FIG. 8 is a perspective view showing a pack tray of a battery pack according to one embodiment of the present invention.

[0045] FIG. 9 shows a venting path of a battery pack according to one embodiment of the present invention and is a cross-sectional view of the battery pack of FIG. 1 cut along line B-B'.

[0046] FIG. 10 is a diagram showing a venting path on the lower surface of a pack tray of a battery pack according to one embodiment of the present invention.

[0047] Figure 11 is a graph showing the time when a battery unit adjacent to a battery unit that experienced a thermal event in a battery pack of a comparative example ignites.

[0048] Figure 12 is a graph showing the heat flux over time in different parts of a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack of a comparative example.

[0049] FIG. 13 is a graph showing the time when a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack according to one embodiment of the present invention ignites.

[0050] FIG. 14 is a graph showing the heat flux over time in different parts of a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack according to one embodiment of the present invention.

[0051] FIG. 15 is a drawing for explaining an automobile according to an embodiment of the present invention.

[0052]

[0053] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0054] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0055] In addition, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar configurations are omitted, and the focus is on the differences.

[0056] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0057] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0058] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0059] In the following, the statement that any configuration is placed on the "upper (or lower) side" of a component or on the "upper (or lower) side" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of the component, but also that another configuration may be interposed between the component and any configuration placed on (or below) the component.

[0060] Furthermore, where it is stated that one component is "connected," "combined," or "joined" to another component, it should be understood that while the components may be directly connected or joined to each other, another component may be "interposed" between each component, or that each component may be "connected," "combined," or "joined" through another component.

[0061] Singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "composed of" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be omitted or additional components or steps may be included.

[0062] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less unless specifically stated otherwise.

[0063] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in the present invention, these terms are used merely for convenience of explanation and may vary depending on the position of the object or the position of the observer, as is obvious to those skilled in the art of the present invention.

[0064] For example, in an embodiment of the present invention, the X-axis direction shown in the drawing may mean the width direction or the left-right direction, the Y-axis direction may mean the length direction or the front-back direction perpendicular to the X-axis direction on the horizontal plane (XY plane), and the Z-axis direction may mean the up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0065] FIG. 1 is a perspective view of a battery pack according to an embodiment of the present invention, excluding the upper tray. FIG. 2 is an exploded perspective view of a battery pack according to an embodiment of the present invention.

[0066] Referring to FIGS. 1 and 2, the battery pack (10) may include a battery unit (100), a pack tray (200), and a base plate (300). In addition to the components described above, the battery pack (10) may additionally include a control module (400) and a cooling module (500).

[0067] The battery unit (100) may be equipped with multiple battery cells.

[0068] Multiple battery cells may be electrically connected to one another. Multiple battery cells may be stacked along a single direction. For example, multiple battery cells may be arranged side by side in the left-right direction (X-axis direction) while standing upright in the vertical direction (Z-axis direction). More specifically, multiple battery cells may comprise an electrode assembly, a cell case housing the electrode assembly, and electrode leads configured to protrude toward the front and / or rear side of the cell case. The battery cells may have various structures, and additionally, multiple battery cells may be stacked in various ways. The number of multiple battery cells and the stacking method may be designed in various ways depending on the size of the battery accommodation space of the electric vehicle to which they are applied.

[0069] The battery unit (100) may further include a case. The case may be configured to accommodate a battery cell. Specifically, an internal space may be formed in the case, and the case may be configured to accommodate a battery cell within the internal space. The case may surround a plurality of battery cells and thereby protect the battery cells from external vibrations or shocks. Such a case may be made of a metal material having rigidity and heat resistance to physically or chemically protect the accommodated battery cells.

[0070] For example, the case may have a rectangular shape. The case may include an upper case, a lower case (e.g., 101 with reference to FIG. 5), a left case, a right side case, a front case, and a rear case. Here, at least some parts may be formed integrally. However, the structure and shape of the case are not limited by the embodiments and can be designed in various ways.

[0071] The battery unit (100) according to the present invention may be a cell stack in which multiple battery cells are electrically connected to form a single unit as illustrated, or it may be a battery module in which one or more such cell stacks are housed in a module case. That is, the case may be omitted to reduce the weight and volume of the battery unit (100). The battery pack (10) of the present invention may be manufactured by a cell-to-pack process. For example, the battery unit (100) may be defined as a battery module, a cell stack, a cell array, a cell assembly, etc. However, for convenience of explanation, the following description will focus on the case in which a case is provided and the battery cells are housed in the case.

[0072] A pack tray (200) can accommodate a battery unit (100). A pack tray (200) can accommodate a plurality of battery units (100). A plurality of battery units (100) can be spaced apart at regular intervals inside the pack tray (200). Referring to FIGS. 1 and 2, a plurality of battery units (100) can be spaced apart and aligned in the length direction (Y-axis direction) and the width direction (X-axis direction).

[0073] The pack tray (200) may be equipped with a lower tray (210), a side tray (220), and an upper tray (230).

[0074] The lower tray (210) can support the battery unit (100) at the bottom of the battery unit (100). The lower tray (210) can be configured to accommodate a plurality of battery units (100). The lower tray (210) may include an upper surface (210a) facing the plurality of battery units (100) and a lower surface (210b) facing the opposite direction of the upper surface (210a) and facing the base plate (300). The lower tray (210) may be formed in the shape of a square plate, but is not limited thereto. The lower tray (210) may form the bottom portion of the pack tray (200).

[0075] The side tray (220) may be configured to extend upward from the edge of the lower tray (210). The side tray (220) defines the height of the pack tray (200) and may form a pre-set space between it and the lower tray (210). A plurality of battery units (100) may be seated in the space between the side tray (220) and the lower tray (210). The side tray (220) and the lower tray (210) may be formed integrally. At least one venting device (600) configured to discharge venting gas, etc., to the outside of the battery pack (10) may be attached or coupled to the side tray (220).

[0076] The upper tray (230) can be coupled to the side tray (220). The upper tray (230) may be formed in the shape of a square plate, but is not limited thereto.

[0077] A pack tray (200) surrounds a plurality of battery units (100), thereby protecting the battery units (100) from external vibrations or shocks. This pack tray (200) may be made of a metal material having rigidity and heat resistance to physically or chemically protect the contained battery units (100). For example, the pack tray (200) may include aluminum. For example, the pack tray (200) may have a rectangular shape. However, the structure and shape of the pack tray (200) are not limited by the embodiments and can be designed in various ways.

[0078] Additionally, the battery pack (10) according to the present embodiment may include, for example, a control module (400) configured to control the charging and discharging of pouch-type battery cells. This control module (400) may include, for example, a Battery Management System (BMS) and a battery cutoff module, and may be housed inside the pack tray (200) together with the battery unit (100).

[0079] A base plate (300) may be located at the bottom of a pack tray (200). The base plate (300) may be configured to support the pack tray (200) at the bottom of the pack tray (200). The base plate (300) may be located at the bottom of a lower tray (210). The base plate (300) may be combined with the pack tray (200). For example, the base plate (300) and the pack tray (200) may be joined and / or fixed to each other by welding, adhesive, etc. Meanwhile, the lower surface of the base plate (300) may be directly joined and / or fixed to the vehicle body. Also, according to another embodiment, the base plate (300) may be formed integrally with the pack tray (200).

[0080] According to an embodiment of the present invention, the base plate (300) can support the pack tray (200). Additionally, the base plate (300) can seal the lower side of the pack tray (200) to prevent heat and / or gas generated in the battery unit (100) from spreading randomly. Furthermore, the base plate (300) can control the direction of heat and / or gas movement to delay or prevent transfer to other battery units (100).

[0081] Referring to FIG. 2, the cooling module (500) may be located on the upper side of the battery unit (100). The cooling module (500) may be placed in the empty space formed between the battery unit (100) and the upper tray (230).

[0082] FIG. 3 is a top view of a pack tray of a battery pack according to an embodiment of the present invention. FIG. 4 is a cross-sectional view of the battery pack of FIG. 1 according to an embodiment of the present invention, cut along line A-A'. FIG. 5 is an enlarged view of section C of FIG. 4. FIG. 6 shows the heat conduction path of a battery pack according to an embodiment of the present invention.

[0083] Referring to FIGS. 4 and 5, the lower case (101) of the battery unit (100) may be provided with at least one venting portion (110). The venting portion (110) may be configured so that when a thermal event occurs in the battery unit (100), venting gas generated within the battery unit (100) is vented downward and discharged to the outside of the battery unit (100). The venting portion (110) may be configured, for example, in the form of a hole.

[0084] The venting section (110) may be provided in multiple numbers. The multiple venting sections (110) may be spaced apart at regular intervals in the horizontal direction. For example, the multiple venting sections (110) may be spaced apart in the width direction (X-axis direction). The number and location of the venting sections (110) may correspond to the number and location of the venting holes (240) of the pack tray (200) to be described later. However, the shape and structure of the venting section (110) are not limited by the embodiment and may be designed in various ways.

[0085] According to an embodiment of the present invention, when thermal runaway occurs in a battery unit (100), gas or flame generated inside the battery unit (100) can be discharged to the outside of the battery unit (100) through a venting section (110). Specifically, directional venting can be induced toward the lower side of the battery unit (100).

[0086] According to the embodiment of the present invention, even if a thermal event occurs within the battery unit (100), the risk of direct damage to passengers in the vehicle or sequential damage to other vehicles can be prevented.

[0087] The lower tray (210) may be provided with ribs (250) and venting holes (240). The ribs (250) and venting holes (240) may each be provided in multiple numbers and may be arranged to intersect each other.

[0088] The rib (250) can be configured to serve as a heat transfer medium and simultaneously guide the movement of venting gas, etc. The rib (250) can be located between multiple adjacent venting holes (240). The rib (250) may refer to a portion that extends from the lower tray (210) and protrudes downward between multiple adjacent venting holes (240).

[0089] Multiple ribs (250) may be spaced apart at regular intervals. Referring to FIG. 3, multiple ribs (250) may be spaced apart and aligned in the length direction (Y-axis direction) and width direction (X-axis direction).

[0090] The rib (250) may be formed at a position corresponding to the position where the battery unit (100) is seated. That is, the rib (250) may be configured so that its upper portion is covered by the battery unit (100). Referring to FIG. 3, the rib (250) may be located at the portion where the battery unit (100) is seated (for convenience of explanation, the position where the battery unit (100) is seated is indicated by a dotted line in FIG. 3).

[0091] At this time, a plurality of ribs (250) may be arranged at the bottom of a single battery unit (100). For example, when there is a first battery unit (100a) and a second battery unit (100b) arranged side by side, the plurality of ribs (250) located at the bottom of the first battery unit (100a) may be defined as the first rib unit (250a), and the plurality of ribs (250) located at the bottom of the second battery unit (100b) may be defined as the second rib unit (250b). That is, the ribs (250) may be composed of a plurality of rib units (250a, 250b) corresponding to the plurality of battery units (100). The plurality of rib units (250a, 250b) may be designed to have substantially the same structure and shape.

[0092] At this time, the rib (250) may face only one battery unit (100). For example, when there are a first battery unit (100a) and a second battery unit (100b) placed side by side, the rib (250) may face only one of the first battery unit (100a) or the second battery unit (100b). That is, the rib (250) may not be positioned to face both the first battery unit (100a) and the second battery unit (100b) between the first battery unit (100a) and the second battery unit (100b).

[0093] According to an embodiment of the present invention, when a thermal event occurs in a battery unit (100), heat and / or venting gas generated in the battery unit (100) can move along the rib (250). Additionally, it is possible to prevent heat and / or venting gas generated in the battery unit (100) from moving to another battery unit (100). In other words, since the heat of one battery unit (100) does not go to an adjacent battery unit (100) but is transferred to a base plate (300) along the rib (250) located below that battery unit (100), the rate of heat transfer to an adjacent battery unit (100) can be slowed down. Therefore, the heat flux to an adjacent battery unit (100) can be reduced, and thermal runaway can be prevented. Here, heat flux may refer to the speed at which heat is transferred from the battery unit (100) where the thermal event occurred to an adjacent battery unit (100).

[0094] Referring to FIGS. 4 and 5, the rib (250) may be formed to protrude downward. That is, the vertical length (h) of the rib (250) may be formed to be longer than the vertical length of the lower tray (210) excluding the rib (250). For example, the vertical length (h) of the rib (250) may be approximately 2 mm or more and 10 mm or less. For example, the vertical length (h) of the rib (250) may be approximately 4 mm or more and 8 mm or less. For example, the vertical length (h) of the rib (250) may be approximately 6 mm or more and 7 mm or less.

[0095] According to an embodiment of the present invention, the ribs (250) are formed to extend downward, so that heat and / or venting gas, etc., can move downward along the ribs (250). Specifically, heat generated in the battery unit (100) can be conducted through the ribs (250). In other words, the ribs (250) can be a heat transfer medium. Additionally, venting gas, particles, etc. generated in the battery unit (100) can move between the ribs (250) arranged side by side. That is, the ribs (250) can be configured to guide the movement path of the venting gas.

[0096] According to one embodiment, the rib (250) may be formed to extend in the longitudinal direction (Y-axis direction) of the battery unit (100). For example, the rib (250) may be in the form of a bar extended in the longitudinal direction. Additionally, a plurality of ribs (250) may be spaced apart in the width direction (X-axis direction) of the battery unit (100). At this time, a venting hole (240) may be formed between the plurality of ribs (250) spaced apart in the width direction. However, the shape and structure of the rib (250) are not limited by the embodiment and may be designed in various ways.

[0097] The rib (250) may include a metal with high thermal conductivity. For example, the rib (250) may include aluminum. The rib (250) is formed integrally with the lower tray (210) and may be formed from substantially the same material. Thus, the rib (250) can absorb heat.

[0098] The upper surface of the rib (250) can come into direct contact with the battery unit (100). Therefore, heat generated from the battery unit (100) can be directly transferred to the rib (250). At this time, as the area of ​​the rib (250) in contact with the battery unit (100) increases, the heat flow rate may decrease. Therefore, referring to FIGS. 3 and FIGS. 5, the heat flow rate can be controlled by forming the width (w) of the rib (250) wide.

[0099] Additionally, the lower surface of the rib (250) may come into direct contact with the base plate (300). That is, the base plate (300) is positioned so as to be spaced apart from the lower tray (210) and may come into contact with the lower surface of the rib (250). In other words, the rib (250) may be positioned between the battery unit (100) and the base plate (300). The rib (250) may be configured to connect the battery unit (100) and the base plate (300) through surface contact.

[0100] According to the above embodiment of the present invention, since the ribs (250) of the lower tray (210) are in direct contact with the battery unit (100), heat transfer can be achieved more effectively. In addition, since heat generated from the battery unit (100) is conducted through the ribs (250) extending downward, heat transfer to adjacent battery units (100) can be prevented and / or minimized.

[0101] Referring to FIG. 6, heat generated in the battery unit (100) can be configured to be transferred vertically through the ribs (250), and the heat transferred through the ribs (250) can be transferred horizontally through the base plate (300). The ribs (250) can transfer heat generated in the battery unit (100) to the base plate (300). At this time, the ribs (250) can be defined as a vertical heat transfer path (P1), and the base plate (300) can be defined as a horizontal heat transfer path (P2).

[0102] According to an embodiment of the present invention, heat generated in a battery unit (100) can be prevented from spreading or being transferred in a horizontal direction to an adjacent battery unit (100).

[0103] The rib (250) may be formed integrally with the lower tray (210). For example, the pack tray (200) may be configured to be formed by at least one process among casting, cutting, stamping, welding, and die casting. According to one embodiment, the pack tray (200) may be configured to be formed by a die casting process. Die casting may be a high-precision process in which metal is melted and then the molten metal is injected into a die using high pressure. Through the die casting process, the structure of the rib (250) can be realized simultaneously with the production of the pack tray (200).

[0104] Conventionally, a rib structure was not implemented in the lower tray, and a separate bottom plate component was attached to the lower side of the lower tray. The vertical length of the bottom plate was formed lower than the rib (250), which made it difficult to reduce the heat conduction rate. For example, the bottom plate was manufactured to be approximately 1 mm.

[0105] According to the above embodiment of the present invention, complex shapes such as ribs (250) can be easily implemented, and since ribs (250) can also be manufactured when molding the pack tray (200), it is effective for mass production and can reduce manufacturing costs. In addition, compared to a conventional structure that uses additional parts (e.g., bottom plates) equipped with ribs, such parts can be omitted, thereby reducing material costs.

[0106] Venting holes (240) may be located between multiple adjacent ribs (250). Multiple venting holes (240) may be spaced apart at regular intervals. Referring to FIG. 3, multiple venting holes (240) may be spaced apart and aligned in the length direction (Y-axis direction) and the width direction (X-axis direction).

[0107] The venting hole (240) may be formed at a position corresponding to the position where the battery unit (100) is seated. That is, the venting hole (240) may be configured so that its upper portion is covered by the battery unit (100). Referring to FIG. 3, the venting hole (240) may be located inside the position where the battery unit (100) is seated (for convenience of explanation, the position where the battery unit (100) is seated is indicated by a dotted line in FIG. 3).

[0108] According to one embodiment, the venting hole (240) may extend in the longitudinal direction (Y-axis direction) of the battery unit (100). For example, the venting hole (240) may have a closed loop shape in the form of a bar extending in the longitudinal direction. According to one embodiment, a plurality of venting holes (240) may be spaced apart in the width direction of the battery unit (100). At this time, a rib (250) may be formed between the plurality of venting holes (240) spaced apart in the width direction. However, the shape and structure of the venting hole (240) are not limited by the embodiment and may be designed in various ways.

[0109] Referring to FIGS. 4 and 5, the venting hole (240) may be configured to communicate with the venting portion (110) formed in the battery unit (100). The venting hole (240) may communicate vertically with the venting portion (110). The venting hole (240) may be formed at a position corresponding to the location where the venting portion (110) is formed.

[0110] According to an embodiment of the present invention, the venting gas generated in the battery unit (100) can be moved downward through the venting hole (240) and discharged to the outside of the battery pack (10). That is, the venting gas generated in the battery unit (100) can be induced to vent downward. In other words, a path for the movement of the venting gas generated in the battery unit (100) can be provided. Therefore, the venting gas can be moved downward without affecting the adjacent battery unit (100), thereby preventing and / or minimizing heat transfer to the adjacent battery unit (100).

[0111] At this time, the venting hole (240) may face only one battery unit (100). When there are a first battery unit (100a) and a second battery unit (100b) arranged side by side, the venting hole (240) may face only one of the first battery unit (100a) or the second battery unit (100b). That is, the venting hole (240) may not be arranged to face both the first battery unit (100a) and the second battery unit (100b) between the first battery unit (100a) and the second battery unit (100b).

[0112] According to an embodiment of the present invention, when a thermal event occurs in a battery unit (100), the venting gas generated in the battery unit (100) can be prevented from moving to another battery unit (100) through the venting hole (240). Accordingly, heat transfer to an adjacent battery unit (100) can be prevented and / or minimized, and the rate of heat transfer to an adjacent battery unit (100) can be slowed down.

[0113] FIG. 7 is a view of the pack tray of a battery pack according to an embodiment of the present invention from the bottom. FIG. 8 is a perspective view showing the pack tray of a battery pack according to an embodiment of the present invention. FIG. 9 is a cross-sectional view of the battery pack of FIG. 1 cut along line B-B' showing the venting path of a battery pack according to an embodiment of the present invention. FIG. 10 is a drawing showing the venting path from the bottom surface of the pack tray of a battery pack according to an embodiment of the present invention.

[0114] A vertical venting channel (B1) configured to transmit venting gas introduced into the venting hole (240) in a vertical direction may be formed in the lower tray (210). The vertical venting channel (B1) may be surrounded by the lower tray (210), the base plate (300), and ribs (250) located on both sides of the vertical venting channel (B1).

[0115] According to an embodiment of the present invention, the venting hole (240) may be configured to induce directional venting in a downward direction.

[0116] Additionally, the lower tray (210) may further have a recessed groove (260) extending upward from the lower surface of the lower tray (210). The groove (260) may be positioned adjacent to a plurality of venting holes (240). For example, the groove (260) may be positioned to face the ends of the plurality of venting holes (240). For example, the groove (260) may be positioned perpendicular to the plurality of venting holes (240). For example, the groove (260) may be formed to extend in the width direction (X-axis direction). A plurality of grooves (260) may be provided at the edges and / or center of the lower tray (210).

[0117] The groove (260) can serve as a passage for venting gas. That is, a horizontal venting channel (B2) can be formed by the groove (260). The horizontal venting channel (B2) can be configured to discharge the venting gas introduced through the vertical venting channel (B1) to the outside. The horizontal venting channel (B2) can be surrounded by the groove (260) and the base plate (300). The horizontal venting channel (B2) can be configured to be directly or indirectly connected to the vertical venting channel (B1). The horizontal venting channel (B2) can be positioned adjacent to the vertical venting channel (B1). Alternatively, although not shown in the drawing, the horizontal venting channel (B2) can be positioned to communicate with the vertical venting channel (B1).

[0118] That is, with reference to FIG. 10, venting gas, etc. generated in the battery unit (100) can be rapidly discharged to the outside of the battery pack (10) through a vertical venting path (B1), a horizontal venting path (B2), and a venting device (600). According to the present invention, by directly implementing a venting path in the pack tray (200), the discharge of venting gas, etc. is not only faster and easier, but also prevents heat transfer to other battery units (100) and prevents thermal runaway phenomena.

[0119] FIG. 11 is a graph showing the time at which a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack of a comparative example ignites. FIG. 12 is a graph showing the heat flux over time by part of a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack of a comparative example. FIG. 13 is a graph showing the time at which a battery unit adjacent to a battery unit where a thermal event occurred ignites in a battery pack according to an embodiment of the present invention. FIG. 14 is a graph showing the heat flux over time by part of a battery unit adjacent to a battery unit where a thermal event occurred in a battery pack according to an embodiment of the present invention.

[0120] First, the simulation conditions can be defined such that a first battery unit (100a), a second battery unit (100b), and a third battery unit (100c) are arranged side by side from left to right (in the direction of the X-axis) within the battery pack (10), and a thermal event occurs on the left side of the second battery unit (100b), which is positioned between the first battery unit (100a) and the third battery unit (100c), and then transfers to the right side. Additionally, the first battery unit (100a) and the third battery unit (100c) can be defined as battery units adjacent to the battery unit where the thermal event occurred. The battery pack of the comparative example differs from the battery pack (10) only in that it does not have a pack tray (200) as in the battery pack (10) of the present invention.

[0121] Referring to FIG. 11, in the battery pack of the comparative example, an adjacent battery unit may ignite approximately 1,000 seconds after a thermal event occurs in any one battery unit. Specifically, the first battery unit (100a) ignited approximately 1,000 seconds after a thermal event occurred in the second battery unit (100b), and the third battery unit (100c) ignited approximately 1,100 seconds later. More specifically, for example, the thermal runaway may continue for approximately 357 seconds in the battery unit (100b) where the thermal event occurred, and then the adjacent battery unit (100a) may ignite approximately 600 seconds later.

[0122] Ignition of adjacent battery units (100a, 100c) may be caused by heat transfer from the battery unit (100b) where a thermal event occurred. In this case, the heat transfer may be due to conduction and / or radiation and / or convection. In particular, the main factors causing ignition of adjacent battery units (100a, 100c) may be radiation in the lateral direction of the battery unit and conduction in the downward direction of the battery unit.

[0123] In particular, referring to FIG. 12, when measuring the heat flux according to time and the location (e.g., upper, side, lower) of adjacent battery units (100a, 100c), it can be confirmed that the heat flux at the lower surface of adjacent battery units (100a, 100c) continuously increases. The heat flux at the lower surface of adjacent battery units (100a, 100c) is the highest and the slope may be the steepest compared to the upper or side surfaces. The heat flux at the lower surface of adjacent battery units (100a, 100c) is approximately 4 kW / m² 200 seconds after the event occurs. 2 6kW / m or more 2 It may be as follows. Since the heat flux is greatest at the bottom surface, the experimental results indicate that managing the heat flux at the bottom surface allows for more effective control of heat transfer to adjacent battery units.

[0124] Meanwhile, according to the present invention, with reference to FIG. 13, when a thermal event occurs in a battery unit (100b), adjacent battery units (100a, 100c) may ignite approximately 1600 seconds after the thermal event occurs. For example, the battery unit (100b) where the thermal event occurred and the adjacent battery units (100a, 100c) may ignite approximately 1600 seconds or more and 1800 seconds or less. It can be confirmed that the ignition time is delayed compared to the comparative example as a result of managing the heat flow rate on the bottom surface by using a pack tray (200) equipped with ribs (250) in the battery pack (10) according to an embodiment of the present invention.

[0125] Additionally, referring to FIG. 14, as a result of measuring the heat flux according to time and the parts of adjacent modules (e.g., upper, side, lower), it can be confirmed that the heat flux at the bottom surface of adjacent battery units (100a, 100c) has decreased when compared to the measurement result of the battery unit of the comparative example (see FIG. 12). The heat flux at the bottom surface of adjacent battery units (100a, 100c) is approximately 3 kW / m at 200 seconds. 2 5kW / m or more2 It may be less than. The heat flux at the bottom surface of adjacent battery units (100a, 100c) is approximately 4 kW / m at 200 seconds. 2 It can be seen that by using a pack tray (200) equipped with ribs (250) in a battery pack (10) according to an embodiment of the present invention, the heat flux on the bottom surface can be reduced compared to the comparative example, thereby reducing heat transfer to adjacent battery units (100a, 100c).

[0126] As a result, when comparing the measurement results for the battery unit of the comparative example (Figs. 11 and 12) with the measurement results for the battery unit according to the present invention (Figs. 13 and 14), it can be seen that the rate of heat transfer from the battery unit (100b) where a thermal event occurred to the adjacent battery units (100a, 100c) is reduced, and the heat flow rate from the lower surface of the adjacent battery units (100a, 100c) is also reduced.

[0127] FIG. 15 is a drawing for explaining an automobile according to an embodiment of the present invention.

[0128] Referring to FIG. 15, the automobile (1) according to the present invention may include at least one battery pack (10) according to the present invention.

[0129] The battery pack (10) according to the present invention can be applied to a vehicle such as an electric vehicle or a hybrid vehicle. That is, the vehicle (1) according to the present invention may include the battery pack (10) according to the present invention. In addition, the vehicle (1) according to the present invention may include various other components included in the vehicle in addition to the battery pack (10). For example, the vehicle (1) according to the present invention may include, in addition to the battery pack (10) according to the present invention, a vehicle body, a motor, a control device such as an ECU (electronic control unit), etc. The vehicle (1) includes four-wheeled vehicles and two-wheeled vehicles. The vehicle (1) may operate by receiving power from the battery pack (10) according to one embodiment of the present invention.

[0130] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

Claims

1. Battery unit; A pack tray for accommodating the battery unit, comprising a lower tray that supports the battery unit at the bottom of the battery unit; and A base plate configured to support the pack tray at the bottom of the pack tray; comprising A battery pack having a plurality of ribs, the lower tray protruding downward and having an upper surface in direct contact with the battery unit.

2. In Paragraph 1, A battery pack characterized by the above-mentioned battery unit having a venting section configured to vent the venting gas downward when a thermal event occurs.

3. In Paragraph 1, A battery pack characterized in that the above-mentioned rib faces only one battery unit.

4. In Paragraph 1, The above rib extends in the longitudinal direction of the battery unit, and A battery pack characterized in that a plurality of the above-mentioned ribs are spaced apart in the width direction of the battery unit.

5. In Paragraph 1, A battery pack characterized by the vertical length of the above rib being 2mm or more and 10mm or less.

6. In Paragraph 1, A battery pack characterized by being configured such that heat generated in the battery unit is transferred vertically through the ribs, and the heat transferred through the ribs is transferred horizontally through the base plate.

7. In Paragraph 1, A battery pack characterized by the above-mentioned pack tray being configured to be formed by a die-casting process.

8. In Paragraph 1, A battery pack characterized in that the base plate is positioned so as to be spaced apart from the lower tray and contacts the lower surface of the rib.

9. In Paragraph 2, A battery pack characterized by further comprising: at least one venting hole configured to be located between a plurality of adjacent ribs and communicating with the venting portion.

10. In Paragraph 9, A vertical venting channel is formed in the lower tray above to transmit the venting gas introduced into the venting hole in a vertical direction, and A battery pack characterized in that the vertical venting channel is surrounded by the lower tray, the base plate, and the ribs located on both sides of the vertical venting channel.

11. In Paragraph 10, The lower tray above Further comprising a recessed groove portion extending upward from the lower surface of the lower tray; and A battery pack characterized by being configured to discharge venting gas introduced through the vertical venting channel to the outside through the horizontal venting channel formed by the groove.

12. In Paragraph 11, A battery pack characterized in that the above-mentioned groove is positioned adjacent to the plurality of venting holes and is formed to extend in the width direction of the battery unit.

13. In Paragraph 11, A battery pack characterized in that the horizontal venting channel is surrounded by the groove and the base plate.

14. In Paragraph 1, A battery pack characterized by further including a cooling module located on the upper side of the battery unit.

15. An automobile comprising a battery pack according to any one of paragraphs 1 through 14.

Images