Battery module with improved safety

Abstract

The present invention discloses a battery module etc. configured to improve safety when a thermal event occurs inside the battery module. The battery module according to one aspect of the present invention includes a cell assembly having a plurality of battery cells electrically connected to each other via electrode leads, a module case that houses the cell assembly in an internal space, and a cover member attached to a side of the cell assembly from which the electrode leads protrude in the internal space of the module case.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2021-0181113 filed on December 16, 2021 and Korean Patent Application No. 10-2022-0166952 filed on December 2, 2022, and the entire contents disclosed in the specification and drawings of said applications are incorporated herein by reference.

[0002] The present invention relates to a battery, and more particularly to a battery module with improved safety, and a battery pack and a vehicle including the same. [Background technology]

[0003] In recent years, as the demand for portable electronic products such as notebook computers, video cameras, and mobile phones has increased dramatically and robots, electric vehicles, and the like have been commercialized in earnest, active research has been conducted on high-performance secondary batteries that can be repeatedly charged and discharged.

[0004] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries are attracting attention due to their advantages of being freely chargeable and dischargeable since they hardly have a memory effect compared to nickel-based secondary batteries, as well as their extremely low self-discharge rate and high energy density.

[0005] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive and negative active materials, respectively, and includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with the positive and negative active materials are arranged with a separator sandwiched therebetween, and an exterior material that encloses the electrode assembly together with an electrolyte, i.e., a battery case.

[0006] In general, lithium secondary batteries can be broadly classified into can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of an aluminum laminate sheet, depending on the shape of the exterior material.

[0007] Recently, secondary batteries are widely used for driving and storing energy not only in small devices such as portable electronic devices but also in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS). A battery module can be configured by housing a plurality of such secondary batteries together inside a module case in an electrically connected state. A battery pack can be configured by connecting a plurality of such battery modules.

[0008] However, when multiple secondary batteries (battery cells) or multiple battery modules are densely packed in a small space, they may be vulnerable to thermal events. In particular, when an event such as thermal runaway occurs in a battery cell, high-temperature gas, flames, heat, etc. may be generated. If such gas, flames, heat, etc. are transmitted to other battery cells included in the same battery module, it may lead to an explosive chain reaction such as thermal propagation. Such a chain reaction may not only cause accidents such as fire or explosion in the battery module, but also cause fire or explosion in other battery modules.

[0009] Furthermore, in the case of medium- to large-sized battery packs such as those in electric vehicles, a large number of battery cells and battery modules are included to increase output and / or capacity, and the risk of thermal chain reactions may become increasingly high. In addition, in the case of battery packs mounted on electric vehicles, users such as drivers may be present in the vicinity. Therefore, if a thermal event occurring in a particular battery cell or module cannot be properly controlled and a chain reaction occurs, it may cause serious damage to property and even damage to human life.

[0010] In particular, in the case of a conventional battery module, an insulating cover may be disposed at a portion where an electrode lead of each battery cell is disposed in order to ensure insulation between the electrode lead and the module case. In this case, the insulating cover is mainly an injection-molded plastic material, and has a problem of being vulnerable to flame. Therefore, if a flame or vent gas discharged from a particular battery cell is directed toward the insulating cover, the insulating cover melts and is unable to properly protect the welded portion between adjacent electrode leads.

[0011] Furthermore, if the internal discharged material generated as the ignition of the battery cell progresses, that is, the residue generated as the battery cell and the bus bar housing melt, heads toward the electrode lead, it may cause an internal short circuit. Also, if the electrode lead moves freely during the process of the vent gas being ejected, it may come into contact with other electrode leads that are not connected, causing an internal short circuit. Moreover, the portion where the electrode lead is located, i.e., the portion where the terrace portion of the battery cell is located, is relatively wide, so there is a high possibility that the flame and vent gas will flow in a concentrated manner. For this reason, there is a concern that the flame and gas may cause thermal runaway of other battery cells.

[0012] In addition, module terminals or connector terminals are often located where the electrode leads are located, and vent gas or flames may be discharged to the outside of the battery module through gaps or voids formed in such module terminals or connector terminals, which may increase the possibility of thermal runaway propagation between battery modules. Summary of the Invention [Problem to be solved by the invention]

[0013] Therefore, the present invention has been devised to solve the above problems, and aims to provide a battery module configured to improve safety when a thermal event occurs inside the battery module, and a battery pack and automobile including the same.

[0014] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0015] To achieve the above object, a battery module according to one aspect of the present invention includes a cell assembly having a plurality of battery cells electrically connected to each other via electrode leads, a module case that houses the cell assembly in an internal space, and a cover member that is attached to a side of the cell assembly from which the electrode leads protrude in the internal space of the module case.

[0016] Here, the cover member may have at least a portion bonded to electrode leads of a plurality of battery cells arranged in the cell assembly.

[0017] The module case may further include a main body frame having at least one of a front and a rear open end, and an end plate coupled to the open end of the main body frame.

[0018] Furthermore, the electrode leads of the cell assembly may be located on the end plate side, and the cover member may be interposed between the electrode leads of the cell assembly and the end plate.

[0019] Furthermore, the cover member may be configured in the form of a film having an adhesive layer on the surface of a base material layer.

[0020] Furthermore, the cover member may be configured in such a manner that it fills the side portion of the cell assembly from which the electrode leads protrude.

[0021] Furthermore, the cover member may be filled between the seal portions of adjacent battery cells.

[0022] Furthermore, the cover member may fill the entire cell assembly from top to bottom at the front or rear of the cell assembly.

[0023] Furthermore, the cover member may be configured such that its upper and lower ends are bent towards the cell assembly.

[0024] Furthermore, the cover member may be configured to entirely cover the electrode leads of the plurality of battery cells from their upper ends to their lower ends.

[0025] Furthermore, the module case may have a vent hole formed in at least one of the upper and lower portions.

[0026] In addition, the battery module according to the present invention may further include a vent unit disposed outside a portion of the module case where a vent hole is formed, and configured to allow the movement of vent gas discharged from the vent hole.

[0027] In order to achieve the above object, a battery pack according to another aspect of the present invention includes a battery module according to the present invention.

[0028] Furthermore, in order to achieve the above object, a vehicle according to yet another aspect of the present invention includes a battery module according to the present invention. Effect of the Invention

[0029] According to the present invention, even if a thermal event occurs inside the battery module, the safety of the battery module can be ensured to a certain level or higher.

[0030] In particular, according to one aspect of the present invention, when a flame or vent gas occurs from a specific cell inside a battery module, the direction of the flame or vent gas can be controlled.

[0031] Furthermore, according to one embodiment of the present invention, it is possible to suppress or block flames and vent gas from flowing toward the electrode lead.

[0032] Therefore, it is possible to prevent internal discharged matter from adhering to the electrode lead due to flames or vent gas ejected from a particular battery cell, and to prevent internal short circuits and the like caused by damage or looseness of the electrode lead.

[0033] In addition, according to this embodiment of the present invention, since high-temperature gas, flames, etc. do not flow into the electrode lead side of the cell assembly, the propagation of thermal runaway between battery cells can be prevented.

[0034] Furthermore, according to this embodiment of the present invention, it is possible to suppress or block the outflow of flames or vent gas into gaps or holes formed in the module terminals or connector terminals present in the portion of the module case where the electrode leads are located, thereby more effectively preventing the propagation of thermal runaway to other battery modules.

[0035] In addition to these, the present invention can have various other effects, which will be described in the sections for each embodiment, and descriptions of effects that can be easily inferred by a person skilled in the art will be omitted.

[0036] The drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to facilitate a further understanding of the technical ideas of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief description of the drawings]

[0037] [Figure 1] 1 is a perspective view illustrating a schematic configuration of a battery module in an assembled state according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of some components of the battery module of FIG. 1. [Diagram 3] 3 is a partial perspective view of the configuration of FIG. 2 in which some of the components are further disassembled. FIG. [Figure 4] FIG. 3 is a front view of some of the components in FIG. 2. [Diagram 5] 11 is a partial perspective view illustrating a battery module according to another embodiment of the present invention; FIG. [Figure 6] FIG. 6 is a top view of the components of FIG. 5. [Figure 7] 6 is a cross-sectional view taken along the line A3-A3' of FIG. 5. [Figure 8] FIG. 8 is an enlarged view of a portion A4 in FIG. 7. [Figure 9] FIG. 8 is an enlarged view of a portion A6 in FIG. [Figure 10] 13 is an exploded schematic view illustrating some components of a battery module according to still another embodiment of the present invention. FIG. [Figure 11] 11 is a diagram illustrating a schematic cross-sectional configuration of the battery modules in FIG. 10 in a combined state. [Figure 12]13 is an exploded schematic view illustrating some components of a battery module according to still another embodiment of the present invention. FIG. [Figure 13] 13 is a perspective view of a battery module including the components of FIG. 12 viewed from below. FIG. [Figure 14] 14 is a cross-sectional view taken along the line A10-A10' of FIG. 13. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, but are to be construed as being in accordance with the meaning and concept of the technical idea of ​​the present invention, in accordance with the principle that the inventor himself can appropriately define the concept of the term in order to best describe the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are merely the most preferred embodiment of the present invention, and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0039] FIG. 1 is an assembled perspective view illustrating the configuration of a battery module according to one embodiment of the present invention, FIG. 2 is an exploded perspective view of some components of the battery module of FIG. 1, FIG. 3 is a partial perspective view of some components in the configuration of FIG. 2 in a further exploded form, and FIG. 4 is a front view of some components of FIG. 2.

[0040] 1 to 4, a battery module according to the present invention includes a cell assembly 100, a module case 200 and a cover member 300. As shown in FIG.

[0041] The cell assembly 100 may include a plurality of battery cells 110. Here, each battery cell 110 may refer to a secondary battery. The secondary battery may include an electrode assembly, an electrolyte, and a battery case. In particular, the battery cell 110 disposed in the cell assembly 100 may be a pouch-type secondary battery. However, other forms of secondary batteries, i.e., cylindrical batteries and prismatic batteries, may also be adopted in the cell assembly 100 of the present invention.

[0042] A plurality of secondary batteries may be stacked on one another to form the cell assembly 100. For example, a plurality of secondary batteries may be stacked in a shape in which they are arranged side by side in the horizontal direction (X-axis direction in the figure) while standing upright (Z-axis direction in the figure).

[0043] Each battery cell 110 may include an electrode lead 111. In this case, the electrode lead 111 may be located at both ends of each battery cell 110 or at one end. The battery cells 110 may be electrically connected to each other in series and / or parallel through the electrode leads 111. In this case, the electrode leads 111 of each battery cell 110 may be directly connected to each other by contacting each other, or may be indirectly connected to each other through a bus bar or the like. Meanwhile, a secondary battery in which the electrode leads 111 protrude in both directions may be called a bidirectional cell, and a secondary battery in which the electrode leads 111 protrude in one direction may be called a unidirectional cell. FIG. 2 and other figures show a form in which the electrode leads 111 protrude in both directions, forward and backward. However, the present invention is not limited in any way by the specific type or form of such a secondary battery, and various forms of secondary batteries already known at the time of filing of the present invention may be adopted in the cell assembly 100 of the present invention.

[0044] The module case 200 may be configured to have an internal space, i.e., an empty space formed therein, to accommodate the cell assembly 100, as shown in Fig. 2. Furthermore, the module case 200 may be configured in a rectangular parallelepiped shape as shown in Figs. 1 and 2, etc. The cell assembly 100 may be accommodated in the internal space of such a rectangular parallelepiped shape.

[0045] The cover member 300 may be disposed in the internal space of the module case 200 together with the cell assembly 100. In particular, the cover member 300 may be adhered to a side of the cell assembly 100. Furthermore, the cell assembly 100 may be configured so that the electrode lead 111 protrudes in a specific direction, and the cover member 300 may be adhered to the side of the portion of the cell assembly 100 from which the electrode lead 111 protrudes.

[0046] 2 and 3, the cell assembly 100 may have six sides (upper, lower, front, rear, left side, and right side) in a form in which a plurality of battery cells 110 are stacked. In this case, the electrode lead 111 may be disposed on the cell assembly 100 in a form in which it protrudes from a particular side of the cell assembly 100, that is, from the front side and the rear side as shown in the drawings. In this case, the cover member 300 may be attached to the front side and the rear side of the cell assembly 100 where the electrode lead 111 is located.

[0047] The cover member 300 may be made of only an adhesive material, or may be configured to have both an adhesive material and a non-adhesive material. The cover member 300 may continue to maintain its adhesiveness, or may be configured to lose its adhesiveness as the adhesive material hardens in an adhered state. Here, the term "adhesion" may include adhesion.

[0048] According to this embodiment of the present invention, the part where the electrode leads 111 are connected and fixed to each other in the cell assembly 100 can be stably held. In particular, the electrode leads 111 can be connected and fixed to each other in a welded form, and since the cover member 300 is attached to the cell assembly 100 at the part where the electrode leads 111 are present, the welded state of the electrode leads 111 can be stably held. Therefore, even if vent gas or flame is generated from a specific battery cell 110 among various battery cells 110 included in the cell assembly 100, the electrode leads 111 can be protected by the cover member 300. Furthermore, since the welded state and position of the electrode leads 111 can be kept constant by the cover member 300, the movement of the electrode leads 111 due to the ejection pressure of the vent gas or the pressure of the flame can be suppressed. In addition, according to the above embodiment, even if a discharged substance in the form of melted internal components is ejected from a specific battery cell 110, the discharged substance can be prevented from adhering to the electrode lead 111 toward the electrode lead 111. Therefore, it is possible to effectively prevent a short circuit from occurring inside the battery module, particularly on the electrode lead side, due to looseness of the electrode lead 111 or adhesion of discharged matter or the like.

[0049] In addition, according to the above-described embodiment, it is possible to prevent gas, flames, ejected material, and the like emitted from the battery cell 110 from flowing in the direction of the electrode lead 111. Therefore, it is possible to more effectively prevent the propagation of thermal runaway through the terrace portion in the cell assembly 100 where the electrode lead 111 is located.

[0050] In particular, the cover member 300 may be at least partially attached to the electrode leads 111 of the plurality of battery cells 110 arranged in the cell assembly 100 .

[0051] 2 and 3, the electrode leads 111 of the multiple battery cells 110 included in the cell assembly 100 may be connected to each other by a method such as welding. At this time, the cover member 300 may be attached in direct contact with the electrode leads 111 of at least some of the battery cells 110. Furthermore, the cover member 300 may be bonded to all of the electrode leads 111 of the entire battery cells 110.

[0052] 2 to 4, the cover member 300 may be configured to be adhered to at least the outer surface of the electrode lead 111 and cover the outer surface of the electrode lead 111. For example, the electrode lead 111 may be provided on the front side (-Y axis direction in the figures) of the cell assembly 100, and the cover member 300 may be configured to be adhered to the front surface of the electrode lead 111 on such a front side.

[0053] According to this embodiment of the present invention, the electrode lead 111 provided in the cell assembly 100 can be directly bonded to the cover member 300. This can more effectively prevent ejected matter (such as molten particles) from the battery cell 110 from contacting the surface of the electrode lead 111, particularly the outer surface (the front surface or the rear surface). In this case, movement of the electrode lead 111 due to gas, flame, etc. can be more effectively restricted. This can more effectively prevent an internal short circuit, etc. from occurring on the electrode lead 111 side of the battery module.

[0054] The cover member 300 may be configured adjacent to or in contact with the electrode lead 111. Therefore, the cover member 300 may be made of or include a material having electrical insulation properties. In addition, the cover member 300 may include a material having adhesiveness or stickiness in order to be attached to the outer surface of the electrode lead 111. The adhesiveness or stickiness of the cover member 300 may be maintained continuously or may change depending on the temperature, etc.

[0055] The cover member 300 may include various resins and various phase change materials (PCMs) that are known at the time of filing of the present invention. In particular, the cover member 300 may be made of or include a thermally conductive material that is applied to the lower part of the cell assembly 100 inside the battery module. For example, the cover member 300 may include a thermal interface material (TIM) such as thermal grease, thermal paste, or thermal compound. The cover member 300 may include a fire extinguishing material. For example, the cover member 300 may include calcium carbonate.

[0056] Furthermore, the battery module according to the present invention may further include a busbar assembly 400 as shown in Figures 2 and 3. The busbar assembly 400 may be configured to support the electrode leads 111, facilitate connection of the electrode leads 111 to each other, and enable sensing of voltage, etc. from the electrode leads 111. In particular, the busbar assembly 400 may include a module busbar 410 and a busbar housing 420 as shown in Figure 3.

[0057] Here, the module bus bar 410 may be made of an electrically conductive material, i.e., a metal material, and may be configured to electrically connect two or more electrode leads 111 to each other, or to be connected to one or more electrode leads 111 to transmit sensing information to a control unit such as a battery management system (BMS).

[0058] In addition, the bus bar housing 420 may be made of an electrically insulating material, i.e., a plastic material. Furthermore, the bus bar housing 420 may be configured so that the module bus bar 410 is placed and fixed thereon. Furthermore, the bus bar housing 420 may be formed with a slit as shown by S1 in FIG. 3. The module bus bar 410 may be attached to the outside, i.e., the front side, of the bus bar housing 420. In this case, the electrode lead 111 may pass through the slit S1 of the bus bar housing 420 and contact the module bus bar 410 located on the outside. In particular, the electrode lead 111 may be coupled and fixed to the module bus bar 410 alone or in a state where two or more electrode leads are stacked. In this case, the electrode lead 111 may be coupled and fixed to the module bus bar 410 by laser welding, ultrasonic welding, or the like, in addition to the above, various other fastening methods may be applied.

[0059] The cover member 300 may be attached to the electrode lead 111 with at least a portion located on the outside, i.e., the front side, of the bus bar housing 420. For example, as shown in FIG. 2 to FIG. 4, the electrode lead 111 may be configured to be stacked with the module bus bar 410 on the outside, i.e., the front side, of the bus bar housing 420. At this time, the cover member 300 may be adhered to the outside, i.e., the front side, of the electrode lead 111. In this case, the cover member 300 may be adhered to the module bus bar 410 and / or the bus bar housing 420 together with the electrode lead 111. For example, the cover member 300 may be adhered to the front surfaces of the electrode lead 111, the module bus bar 410, and the bus bar housing 420. Meanwhile, although not shown, the cover member 300 may be provided on the rear side of the cell assembly 100 and adhered to the rear surfaces of the electrode lead 111 on the rear side of the cell assembly 100, the module bus bar 410 on the rear side, and the bus bar housing 420 on the rear side.

[0060] Moreover, the battery module according to the present invention may further include a terminal 500 and a connector terminal 600 .

[0061] Here, the terminal 500 may include a positive terminal and a negative terminal. The terminal 500 is made of a metal material having electrical conductivity, such as copper or aluminum, and can function as a path through which a charge / discharge current flows by being connected to other components outside the battery module. The connector terminal 600 can function as a path through which various information and signals of the cell assembly 100, such as electrical characteristics of the cell assembly 100, i.e., the voltage of each battery cell 110 and the total voltage of the cell assembly 100, are exchanged with a control component, such as a battery management system (BMS). The terminal 500 and the connector terminal 600 are components that are widely arranged in a battery module, and detailed description thereof will be omitted.

[0062] The terminal terminals 500 and the connector terminals 600 may be located in the bus bar housing 420 as shown in Fig. 3. However, the present invention is not necessarily limited to this embodiment, and the terminal terminals 500 and the connector terminals 600 may be located in other portions than the bus bar housing 420.

[0063] In this embodiment, the cover member 300 may not be attached to the terminal terminals 500 and the connector terminals 600. In other words, the cover member 300 may be mainly attached to portions other than the terminal terminals 500 and the connector terminals 600, and may be configured such that at least a portion of each of the terminal terminals 500 and the connector terminals 600 is exposed to the outside.

[0064] The module case 200 may include a body frame 210 and an end plate 220 .

[0065] Here, the main body frame 210 may be configured in a form in which at least one of the front and rear is open. In particular, the main body frame 210 may be configured in a form in which the upper, lower, left and right sides are closed and the front and rear are open, as shown in FIG. 2. In this case, the upper, lower, left and right sides may each be configured in a plate shape, and these four plates may be manufactured into a tube shape integrated with each other. The main body frame 210 having such a shape may be called a monoframe. That is, the main body frame 210 may include an upper plate, a lower plate, a left plate and a right plate, and an internal space may be defined by these plates. The cell assembly 100 may be accommodated in the internal space of the main body frame 210 defined in this manner.

[0066] The end plates 220 may be configured to be coupled to the openings of the main body frame 210. For example, when the main body frame 210 is configured as a monoframe with front and rear openings as shown in Figs. 1 and 2, the end plates 220 may be disposed at the front and rear of the main body frame 210, respectively, and coupled to the front opening and the rear opening of the main body frame 210, respectively. In this case, the front and rear of the internal space of the main body frame 210 may be defined by the end plates 220, and the internal space may be entirely closed.

[0067] In this embodiment, the cell assembly 100 may be configured such that the electrode lead 111 of each battery cell 110 is located on the end plate 220 side. That is, referring to FIG. 2, each of the battery cells 110 arranged in the cell assembly 100 may be a pouch-type secondary battery that is configured to be upright in the vertical direction. That is, the wide surface of the housing of each battery cell 110 faces the left-right direction, and the seal portion surrounding the housing of each battery cell 110 may be located at the top, bottom, front, and rear of the housing. The electrode lead 111 may be located at the front side and rear side of each battery cell 110. The battery cells 110 may be arranged so as to be aligned in the horizontal direction, particularly in the left-right direction (X-axis direction). Therefore, it can be said that the terrace portion where the electrode lead 111 is located is located at the front side and rear side of the seal portion of each battery cell 110.

[0068] At least a portion of the cover member 300 may be interposed between the electrode lead 111 and the end plate 220 of the cell assembly 100. That is, at least a portion of the cover member 300 may be located outside (on the front side or rear side) the electrode lead 111 of each battery cell 110. Note that the cover member 300 may be bonded to the electrode lead 111, and an outer surface of the cover member 300 may face the end plate 220.

[0069] According to this embodiment, it is possible to prevent vent gas or flame discharged from a particular battery cell 110 from heading toward the end plate 220. In addition, since the cover member 300 attached to the electrode lead 111 prevents direct contact between the electrode lead 111 and the end plate 220, there is no need for an insulating cover in the form of an ejection, i.e., an ejection cover, which has been included in a battery module in the past. In other words, an ejection cover that is physically separated from the electrode lead 111 and the end plate 220 was required in the past for electrical insulation between the electrode lead 111 and the end plate 220. In addition, if such an ejection cover melts due to flame or gas, it may adhere to the electrode lead, causing an internal short circuit, etc. However, according to the above embodiment of the present invention, since the insulating cover attached to the electrode lead 111 is interposed between the electrode lead 111 and the end plate 220, it is possible to remove the conventional ejection cover.

[0070] In the above embodiment, the main body frame 210 may be made of a metal material such as aluminum or stainless steel. The end plate 220 may also be made of a metal material like the main body frame 210. In particular, the end plate 220 may be made of the same material as the main body frame 210. According to the present invention, since the cover member 300 made of an electrically insulating material can be attached to the outside of the electrode lead 111 of the cell assembly 100, even if the end plate 220 is made of a metal material having electrical conductivity, electrical insulation between the cell assembly 100 and the end plate 220 can be maintained. Alternatively, at least a portion of the module case 200 may include a non-metallic material such as plastic.

[0071] The cover member 300 may be configured in a film form. In particular, the cover member 300 may be configured to include a base layer made of a polymer material and having a thin sheet-like shape, and an adhesive layer may be provided on at least one surface, i.e., the inner surface, of the base layer. For example, referring to the configuration of FIG. 3, in the case of the cover member 300 located on the front side of the cell assembly 100, an adhesive material may be applied to the rear surface of the base layer.

[0072] Here, the cover member 300 may have a thin thickness of 0.5 mm to 1 mm, but the thickness of the cover member 300 may be designed to have other shapes depending on various situations and conditions such as the type, shape, and size of the battery cell 110, and the material of the cover member 300.

[0073] Also, the cover member 300 may be configured in a folded shape so as to enclose the outside of the cell assembly 100. For example, as shown in the portions A2 and A2' in Figs. 2 and 3, the cover member 300 may be configured in a folded shape at both horizontal ends. Then, such folded portions may be folded toward the outer surfaces of the two battery cells 110 located at the outermost positions of the horizontally stacked cell assembly 100. In particular, the folded portions at both horizontal ends of the cover member 300 may be bonded to the outside of the cell assembly 100. That is, the left folded portion and the right folded portion of the cover member 300 as shown in the portions A2 and A2' in Figs. 2 and 3 may be bonded to the left and right surfaces of the cell assembly 100, respectively.

[0074] According to this embodiment of the present invention, the bonding strength between the cover member 300 and the cell assembly 100 is improved, and the position and shape of the cover member 300 can be prevented from being deformed even when vent gas or flame is generated. Therefore, the effect of protecting the electrode lead 111 by the cover member 300 is further improved. In addition, according to the above embodiment, the gap between the cover member 300 and the cell assembly 100 is narrowed or removed, and thus the movement of vent gas or flame to the front and rear sides of the cell assembly 100 can be more effectively prevented.

[0075] The cover member 300 may be configured to fill the side of the cell assembly 100 from which the electrode leads 111 protrude, as will be described in more detail with reference to FIGS.

[0076] Fig. 5 is a partial perspective view showing a schematic view of some components of a battery module according to another embodiment of the present invention. Fig. 6 is a top view of the components of Fig. 5. Fig. 7 is a cross-sectional view taken along the line A3-A3' of Fig. 5. Meanwhile, for various embodiments included in this specification, including this embodiment, detailed descriptions of parts that can be applied in the same or similar manner to other embodiments will be omitted, and the following description will focus on differences.

[0077] 5 to 7, the cell assembly 100 may be configured in such a manner that the electrode lead 111 protrudes from the front side of the cell assembly 100. The module case 200, particularly the end plate 220, may be located on the front side of the cell assembly 100. In this configuration, the cover member 300 may be configured in such a manner that it is filled and adhered to the front side of the cell assembly 100.

[0078] For example, the cover member 300 may be configured to fill at least a portion of the space between the front side of the cell assembly 100 and the end plate 220. In this case, the cover member 300 may be initially injected or applied as an adhesive having viscosity and fluidity, and then configured to be hardened after filling at least a portion of the space between the front side of the cell assembly 100 and the end plate 220. As another example, the cover member 300 may be configured to continue to have viscosity or fluidity without being hardened after being injected or applied to the front side of the cell assembly 100.

[0079] In particular, the cover member 300 may be filled between the sealing portions of adjacent battery cells 110. This will be described in more detail with further reference to FIG.

[0080] FIG. 8 is an enlarged view of a portion A4 in FIG.

[0081] 8, the electrode lead 111 of each battery cell 110 included in the cell assembly 100 may protrude forward. In this case, each battery cell 110 may have a seal portion with the electrode lead 111 interposed therebetween, and a terrace portion may be located on the forward side as indicated by T. An empty space may be formed between the seal portions of each battery cell 110, i.e., between the terrace portions T of each battery cell 110, as indicated by A5. In this case, the cover member 300 may be filled in the space between the seal portions of adjacent battery cells 110, i.e., the space between the terrace portions of adjacent battery cells 110.

[0082] Furthermore, when one sealed portion (terrace portion) is used as a reference, the left and right sides of each sealed portion may be filled with the cover member 300. Although not shown in Fig. 8, the cover member 300 may also be filled in the upper and lower parts of each sealed portion. In this case, the cover member 300 can be said to be configured to enclose all of the upper, lower, left, and right parts of the sealed portion (terrace portion).

[0083] According to this configuration of the present invention, when the internal pressure of a specific battery cell 110 increases due to a situation such as thermal runaway, it is possible to prevent rupture from occurring on the terrace portion side where the electrode lead 111 is located. Therefore, it is possible to more effectively prevent vent gas or flames from being directly ejected or exposed on the end plate 220 side. In addition, according to the above embodiment, the cover member 300 firmly prevents the terrace portion from moving freely, thereby restricting the movement of the electrode lead 111 located on the terrace portion.

[0084] In particular, the cover member 300 may be configured to be located at the front and / or rear of the cell assembly 100 but to fill it entirely from top to bottom.

[0085] For example, as shown in Fig. 5, the cover member 300 located on the front side of the cell assembly 100 may be filled as a whole from the upper end to the lower end of the cell assembly 100. That is, a filling component between terraces such as the portion indicated by A5 in Fig. 8 may be configured to extend in an elongated manner from the upper end to the lower end of the cell assembly 100.

[0086] Furthermore, the cover member 300 may be configured such that the upper and lower ends are folded toward the cell assembly 100. That is, the cover member 300 may be filled up to the upper surface of the cell assembly 100 and have a shape folded onto the upper surface of the cell assembly 100, as shown by the portion B1 in FIG. 5. In this case, the cover member 300 may be adhered to the upper surface of the cell assembly 100. The cover member 300 may be interposed between the upper surface of the cell assembly 100 and the inner surface (lower surface) of the module case 200.

[0087] 5, the cover member 300 may be filled up to the surface of the lower end of the cell assembly 100 and may have a shape bent onto the surface of the lower end of the cell assembly 100. In this case, the cover member 300 may be adhered to the surface of the lower part of the cell assembly 100. The cover member 300 may be interposed between the surface of the lower part of the cell assembly 100 and the inner surface (upper surface) of the module case 200.

[0088] According to this embodiment of the present invention, it is possible to more effectively prevent vent gas, flame, etc. from moving toward the electrode lead 111 of the cell assembly 100. That is, in the case of the above embodiment, the space between the front side and / or rear side of the cell assembly 100 and the end plate 220 is narrowed. In addition, the cover member 300 can prevent vent gas, flame, etc. discharged to the center of the upper end or the center of the lower end of the cell assembly 100 from moving toward the end plate 220. Therefore, according to this embodiment, it is possible to more effectively prevent various problems caused by the movement of flame or vent gas toward the portion where the electrode lead 111 is located or the end plate 220.

[0089] Moreover, such an embodiment further improves the bonding between the cover member 300 and the cell assembly 100. In addition, the above embodiment enables the cover member 300 to more securely protect the electrode lead 111 of the battery cell 110.

[0090] Also, the cover member 300 may be filled between the main body of each battery cell 110 and the bus bar assembly 400 in the horizontal direction. For example, referring to FIG. 8, a receiving portion in each battery cell 110 receiving an electrode assembly and the bus bar assembly 400 may be disposed to be spaced apart from each other by a predetermined distance in the front-rear direction (Y-axis direction in the drawing). In this case, the cover member 300 may be filled in a form interposed between the receiving portion of the battery cell 110 and the bus bar assembly 400, particularly the bus bar housing 420. In this case, it can be said that the cover member 300 is filled (located) between the receiving portion of each battery cell 110 and the electrode lead 111.

[0091] The cover member 300 may be positioned horizontally outside the electrode lead 111. This will be described in more detail with further reference to FIG. 9 in addition to FIG.

[0092] FIG. 9 is an enlarged view of a portion A6 in FIG.

[0093] 7 and 9, the cover member 300 may be located outside the electrode leads 111. As a more specific example, the electrode leads 111 may be located on the front side of the cell assembly 100, and different electrode leads 111 may be in contact with each other. At this time, the electrode leads 111 may be in contact with the module bus bar 410 and may be welded together with the module bus bar 410. In such a configuration, the cover member 300 may be located outside the electrode leads 111, that is, on the front side, as in the portion indicated by A7 in FIG. 9.

[0094] In this case, the cover member 300 can prevent the electrode lead 111 from being exposed to the outside. Furthermore, the end plate 220 can be located on the outside of the electrode lead 111. Therefore, according to the above embodiment, the cover member 300 can be interposed between the electrode lead 111 and the end plate 220. Therefore, when the cover member 300 is made of an electrically insulating material, it is possible to prevent an electrical short circuit between the electrode lead 111 and the end plate 220 even if the end plate 220 is made of a metal material.

[0095] Furthermore, the cover member 300 may be interposed between the electrode leads 111. For example, as shown in the portion indicated by A8 in Fig. 9, the adjacent electrode leads 111 may be spaced apart from each other. At this time, the cover member 300 may be filled between the electrode leads 111. According to this embodiment, it is possible to more securely prevent the electrode leads 111 from moving or coming into unintentional contact with each other.

[0096] Furthermore, in the above embodiment, the cover member 300 may be located outside the bus bar assembly 400. That is, with reference to the embodiment in Fig. 9, the cover member 300 may be located on the front side (-Y axis direction side) of the bus bar assembly 400.

[0097] Furthermore, the cover member 300 may be configured in a form in which it is filled both inside and outside the bus bar assembly 400. For example, the cover member 300 may be filled both inside (rear side) and outside (front side) of the bus bar assembly 400, as shown in Figures 7 to 9.

[0098] According to this embodiment of the present invention, the busbar assembly 400 to which the electrode leads 111 are welded can be securely protected and fixed by the cover member 300. In particular, the busbar housing 420 may be made of a plastic material, and the busbar housing 420 can be more securely prevented from being damaged or melted by a flame or high-temperature vent gas. In addition, in this case, the cover member 300 is disposed (filled) around the busbar assembly 400, so that the free space in the portion where the busbar assembly 400 is located can be narrowed. Therefore, in this case, even if a flame or vent gas occurs from the cell assembly 100, the safety of the battery module can be more reliably guaranteed.

[0099] Meanwhile, when the cover member 300 is disposed around the bus bar assembly 400, the cover member 300 may be configured not to enclose the terminal terminals 500 and the connector terminals 600. That is, as shown in the various drawings described above, the terminal terminals 500 and the connector terminals 600 may be configured to be exposed to the outside, because such terminal terminals 500 and the connector terminals 600 need to be exposed to the outside of the module case 200 to be connected to other external components.

[0100] In particular, when the cover member 300 is configured to be filled on the side of the cell assembly 100, a fluid adhesive material for forming the cover member 300 may be injected into the module case 200 in a state in which the cell assembly 100 is housed. In this case, when the fluid adhesive material is injected into both the front and rear of the bus bar assembly 400, the adhesive material may be configured not to be filled around the terminal terminals 500 and the connector terminals 600 provided on the upper part of the bus bar assembly 400, particularly the upper part. For example, the bus bar housing 420 may have a guide structure such as a partition wall to prevent the adhesive material for the cover member 300 from flowing around the terminal terminals 500 and the connector terminals 600.

[0101] In addition, various structures and manufacturing methods may be applied so that the terminals 500 and the connector terminals 600 are not completely enclosed by the cover member 300 but are exposed to the outside.

[0102] The cover member 300 may be configured to entirely cover the electrode leads 111 of the multiple battery cells 110 from their upper ends to their lower ends.

[0103] For example, as shown in FIG. 5, a cover member 300 may be provided for the electrode lead 111 located on the front side of the bus bar housing 420 so as to cover the electrode lead 111 entirely from its upper end to its lower end.

[0104] In particular, the cover member 300 may be configured to completely cover the entire electrode lead 111 disposed in the cell assembly 100 in the up-down direction. That is, the cover member 300 may be configured to cover the entire electrode lead 111. For example, as shown in Figs. 2, 4, and 5, in the case of the cover member 300 disposed on the front side of the cell assembly 100, the cover member 300 may be configured so that the entire outer surface, i.e., the front surface, of the electrode lead 111 located on the front side of the cell assembly 100 is not exposed to the front side. Therefore, as shown in Fig. 4, when the cell assembly 100 is viewed from the front side, the electrode lead 111 is completely enclosed by the cover member 300 and is not exposed to the outside.

[0105] According to this embodiment of the present invention, the outer side, i.e., the front side, of the electrode lead 111 can be more securely protected and fixed by the cover member 300. Therefore, it is possible to more effectively prevent foreign matter such as molten particles from adhering to the outer side of the electrode lead 111 and to prevent the electrode lead 111 from moving. Furthermore, as shown in the various drawings above, when a plurality of battery cells 110 are stacked in the left-right direction, vent gas or flames generated in a specific battery cell 110 are likely to flow from the upper or lower part to the electrode lead 111 side. Therefore, if the cover member 300 covers the entire electrode lead 111 from the upper end to the lower end as in the above embodiment, the protective effect for the electrode lead 111 is further improved.

[0106] Fig. 10 is a schematic exploded view of some components of a battery module according to yet another embodiment of the present invention, and Fig. 11 is a schematic cross-sectional view of the battery module of Fig. 10 in a combined state. For example, Fig. 11 shows a cross-sectional view taken along line A9-A9' in the combined battery module of Fig. 10.

[0107] 10 and 11, a vent hole, as indicated by H, may be formed in the module case 200. The vent hole H may be configured to penetrate the module case 200. In this configuration, when vent gas is generated and ejected from the cell assembly 100 housed in the internal space of the module case 200, the vent gas may be discharged to the outside of the module case 200 through the vent hole H.

[0108] In particular, the cell assembly 100 may be configured in a form in which a plurality of battery cells 110 are stacked in the left-right direction inside the module case 200, as shown in the various drawings described above. In this case, the vent hole H may be formed on the upper and / or lower side of the module case 200. That is, the module case 200 may include an upper plate and a lower plate, and the vent hole H may be formed in such an upper plate or lower plate. Furthermore, the vent hole H may be configured to extend elongatedly in the left-right direction, which is the stacking direction of the battery cells 110, in the upper plate or lower plate, as shown in FIG. 10.

[0109] According to this embodiment of the present invention, vent gas, flames, etc., ejected from the cell assembly 100 can be smoothly discharged to the outside of the module case 200 through the vent hole H. Therefore, the effect of the present invention, in which the cover member 300 prevents the vent gas, flames, etc. from heading toward the electrode leads 111 located at the front and rear sides of the cell assembly 100, is further improved.

[0110] Furthermore, as in the above-described embodiment, when a plurality of battery cells 110 are arranged in the left-right direction and the front and rear sides, i.e., the terrace sides, of each battery cell 110 are bonded by the cover member 300, the vent gas can be discharged in an upward or downward direction from each battery cell 110. At this time, when the vent hole H is formed in the upper and / or lower part of the module case 200 as in the above-described embodiment, the vent gas and the like can easily flow toward the vent hole H without flowing toward the electrode lead 111 side.

[0111] Thus, in an embodiment in which the module case 200 is provided with the vent hole H, the battery module according to the present invention may further include a vent unit 700 as shown in FIGS.

[0112] The vent unit 700 may be configured to be disposed on at least one side of the module case 200 to allow the movement of vent gas. In particular, the vent unit 700 may be disposed on the outside of the module case 200. Furthermore, the vent unit 700 may be configured to be attached to at least a portion of the module case 200 where the vent hole H is formed. As shown in Figs. 10 and 11, when the vent hole H is located at the top, the vent unit 700 may be attached to the top of the module case 200.

[0113] Also, the vent unit 700 may have a vent channel formed therein. That is, the vent unit 700 may be configured such that the vent gas discharged from the vent hole H flows into an empty space inside, i.e., the vent channel, and can move within the vent channel, as indicated by the arrow in Fig. 11. Furthermore, the vent unit 700 may have an exhaust port formed on at least one side so that the vent gas inside can be discharged to the outside. The vent unit 700 may be made of a metal material such as aluminum or steel.

[0114] According to this embodiment of the present invention, the path of the vent gas discharged from the module case 200 of the battery module, such as the discharge direction and position, can be controlled to eliminate or reduce damage to users and other devices caused by the high-temperature vent gas. Also, according to the above embodiment, the discharge path of the vent gas is bent through the vent unit 700, so that fire-inducing factors such as flames and sparks can be more effectively prevented from being discharged to the outside of the battery module. In this case, various types of blocking structures for blocking materials such as flames and sparks can be provided inside the vent unit 700. Moreover, according to this embodiment of the present invention, the general structure of the battery module, that is, the structure of the module case 200 and the cell assembly 100 provided therein, can be largely changed without needing to provide a large amount of change, and the vent unit 700 can be attached or welded to the outside, so that various controls of the vent gas can be performed with a relatively simple manufacturing process and a simple structure.

[0115] Fig. 12 is a schematic exploded view of some components of a battery module according to still another embodiment of the present invention. Fig. 13 is a perspective view of a battery module including the components of Fig. 12, viewed from below. Fig. 14 is a cross-sectional view taken along the line A10-A10' in Fig. 13. This embodiment will be described with a focus on differences from the above-described embodiment.

[0116] 12 to 14, the cover member 300 may be configured in a form substantially identical to that of Fig. 5, covering the side surfaces of the cell assembly 100, particularly the front side and / or rear side of the cell assembly 100 where the electrode lead 111 is located. However, unlike Fig. 5, the cover member 300 may be configured in a form that does not completely and tightly cover the entire side surface of the cell assembly 100, but does not cover part of the side surface of the cell assembly 100.

[0117] More specifically, as shown in the portion indicated by B3 in Figures 12 and 14, the cover member 300 may be configured not to cover the lower part of the side of the cell assembly 100. Furthermore, the cover member 300 may be configured to be separated from the side of the cell assembly 100 by a predetermined distance in the horizontal direction (front-back direction, Y-axis direction) as shown in Figures 12 and 14. In this case, it can be said that the cover member 300 is configured to cover the outer side of the cell assembly 100 in the horizontal direction, but to be open and not cover the lower part.

[0118] According to this embodiment, it is possible to control the vent gas, etc., through the portion not covered by the cover member 300, i.e., the portion B3. That is, when the vent gas, flame, etc. are generated from the cell assembly 100, such vent gas, etc. can be guided in the downward direction as shown by the arrow in FIG.

[0119] At this time, a vent hole may be formed on the lower side of the module case 200, as shown by H' in Figures 13 and 14. Such a vent hole H' may be provided at a position communicating with an uncovered portion (unfilled portion) B3 of the cover member 300, as shown in Figure 14. Furthermore, in a configuration in which a battery module is placed in a pack case, this embodiment may be more effectively applied when a component that guides vent gas or the like is provided on a portion of the pack case that contacts the lower side of the battery module, i.e., on the bottom side of the pack case.

[0120] According to such an embodiment of the present invention, it is possible to more easily realize a directional venting configuration in which vent gas or flames generated inside the battery module are directed in a specific direction, i.e., toward the lower side of the battery module. Furthermore, according to the above embodiment, it is possible to more reliably prevent vent gas or flames from moving toward the module terminal located on the upper side of the front or rear of the battery module.

[0121] In still another embodiment of the present invention, the vent direction may be controlled by adjusting the filling amount (filling ratio) of the cover member 300. For example, in the embodiment shown in Figs. 12 to 14, the cover member 300 is arranged in a fully filled form on the front and rear sides of the cell assembly 100, but the filling amount of the cover member 300 in the portion B3 may be smaller than that in other portions. In this case, it becomes possible to introduce vent gas or the like into the portion of the cover member 300 that is filled with a smaller amount.

[0122] Meanwhile, in the embodiment configurations of Figures 12 to 14, an embodiment in which the vent gas is guided to the lower side of the battery module is shown, but an embodiment in which the vent gas is guided to the other side, i.e., the upper side, of the battery module can also be prepared.

[0123] A battery pack according to the present invention may include one or more of the battery modules according to the present invention described above. In addition to the battery module, the battery pack according to the present invention may further include various other components, i.e., battery pack components known at the time of filing of the present invention, such as a battery management system (BMS), bus bars, a pack case, a relay, a current sensor, etc.

[0124] The battery module according to the present invention may be applied to automobiles such as electric automobiles and hybrid automobiles. That is, the automobile according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention. The automobile according to the present invention may further include various other components included in the automobile in addition to the battery module or battery pack. For example, the automobile according to the present invention may further include a vehicle body, a motor, a control device such as an electronic control unit (ECU) in addition to the battery module according to the present invention.

[0125] Furthermore, the battery module according to the present invention may be applied to an energy storage system (ESS), i.e., the energy storage system according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention.

[0126] Meanwhile, although directional terms such as up, down, left, right, front, and back are used in this specification, it will be obvious to those skilled in the art of the present invention that these terms are used merely for ease of explanation and may vary depending on the position of the object in question, the position of the observer, etc.

[0127] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the scope of the technical concept of the present invention and the scope of the claims. [Explanation of symbols]

[0128] 100 Cell Assembly 110 Battery Cell 111 Electrode lead 200 module case 210 Main body frame, 220 End Plate 300 Cover member 400 Busbar Assembly 410 module busbar, 420 Busbar Housing 500 Terminal Terminal 600 Connector terminal 700 Vent Unit

Claims

1. A cell assembly including a plurality of battery cells electrically connected to each other via electrode leads; a module case that houses the cell assembly in an internal space; a cover member bonded to a side of the cell assembly from which the electrode leads protrude in an internal space of the module case; Including, The cover member is made of a material having insulating properties and adhesive or cohesive properties, and is configured in the form of a film having an adhesive layer on the surface of a base material layer.

2. The battery module according to claim 1 , wherein at least a portion of the cover member is adhered to electrode leads of a plurality of battery cells arranged in the cell assembly.

3. The battery module according to claim 1 , wherein the module case comprises a main body frame having at least one of a front and a rear open, and an end plate coupled to the open portion of the main body frame.

4. The cell assembly has the electrode lead located on the end plate side, The battery module according to claim 3 , wherein the cover member is interposed between an electrode lead of the cell assembly and the end plate.

5. The battery module according to claim 1 , wherein the cover member has an upper end and a lower end bent toward the cell assembly.

6. The battery module according to claim 1 , wherein the cover member entirely covers the electrode leads of the plurality of battery cells from upper ends to lower ends.

7. The battery module according to claim 1 , wherein the module case has a vent hole formed in at least one of an upper portion and a lower portion.

8. The battery module according to claim 7 , further comprising a vent unit disposed outside a portion of the module case where a vent hole is formed, through which vent gas discharged from the vent hole can move.

9. A battery pack comprising the battery module according to any one of claims 1 to 8.

10. A motor vehicle comprising a battery module according to any one of claims 1 to 8.

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