Battery module with improved safety

Abstract

To provide a battery module configured to improve safety when a thermal event occurs inside the battery module, and a battery pack and a vehicle including the same.SOLUTION: The present invention discloses a battery module, etc., configured to improve safety when a thermal event occurs inside a battery module. The battery module according to an 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.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] This application claims priority based on 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 all of the content disclosed in the specifications and drawings of the applications is incorporated into this application.

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

Background Art

[0003] In recent years, the demand for portable electronic products such as notebook computers, video cameras, and mobile phones has increased rapidly, and as the commercialization of robots, electric vehicles, etc. has become full-scale, research on high-performance secondary batteries that can be repeatedly charged and discharged has been actively conducted.

[0004] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries are particularly notable for their advantages such as being able to be charged and discharged freely because they have almost no memory effect compared to nickel-based secondary batteries, having a very low self-discharge rate, and having a high energy density.

[0005] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such positive electrode active material and negative electrode active material are arranged with a separator in between, and an exterior material that encloses the electrode assembly together with an electrolytic solution, that is, a battery case.

[0006] Generally, lithium secondary batteries can be broadly classified into can-type secondary batteries in which the electrode assembly is built into a metal can, and pouch-type secondary batteries in which the electrode assembly is built into a pouch made of an aluminum laminate sheet, according to the shape of the exterior material.

[0007] Recently, secondary batteries are widely used for driving and energy storage not only in small devices such as portable electronic devices but also in medium- and large-sized devices such as electric vehicles and energy storage systems (ESS). Such secondary batteries can form one battery module in a form where a plurality of them are electrically connected and housed together inside a module case. Note that a plurality of such battery modules can be connected to form one battery pack.

[0008] However, when a plurality of secondary batteries (battery cells) or a plurality of battery modules are densely packed in a narrow space, they can be vulnerable to thermal events. In particular, when an event such as thermal runaway occurs in a certain battery cell, there is a risk of generating high-temperature gas, flame, heat, etc. If such gas, flame, heat, etc. are transmitted to other battery cells contained in the same battery module, there is a risk of an explosive chain reaction situation such as thermal propagation. Note that such a chain reaction can not only cause accidents such as fire and explosion in the battery module, but also has the possibility of causing fire and explosion to other battery modules.

[0009] Furthermore, in the case of a medium to large-sized battery pack such as that of an electric vehicle, a large number of battery cells and battery modules are included to increase the output and / or capacity, and the risk of a thermal chain reaction may gradually increase. Moreover, in the case of a battery pack mounted in an electric vehicle or the like, there may be users such as drivers around. Therefore, if a thermal event occurring in a specific battery cell or module cannot be properly controlled and a chain reaction occurs, it may cause not only serious property damage but also endanger human lives.

[0010] In particular, in the case of a conventional battery module, an insulating cover may be located at the portion where the electrode lead of each battery cell is located to ensure insulation between the electrode lead and the module case. At this time, the insulating cover is mainly an injection product of a plastic material and has a problem of being vulnerable to fire. Therefore, when flames or vent gases discharged from a specific battery cell head towards the insulating cover, the insulating cover will melt and cannot normally protect the welded part between adjacent electrode leads.

[0011] Furthermore, if the internal discharge products generated while the ignition of the battery cell progresses, that is, the residues generated while the battery cell and the bus bar housing are melted, head towards the electrode lead side, there is a risk of causing an internal short circuit. Also, when the electrode lead moves during the process of vent gas ejection, there is a possibility of contact with other non-connected electrode leads and an internal short circuit may occur. Moreover, the portion where the electrode lead is located, that is, the portion where the terrace part of the battery cell is located, has a relatively large space, so there is a high possibility that flames and vent gases will concentrate and flow in. For this reason, there is concern that flames and gases may cause thermal runaway of other battery cells.

[0012] In addition, in many cases, module terminals or connector terminals are located in the portion where the electrode leads are located, and vent gas, flames, etc. may be discharged to the outside of the battery module through gaps or voids formed in such module terminals or connector terminals. In this case, the propagation of thermal runaway between battery modules may be highly likely to occur. Summary of the Invention Problems to be Solved by the Invention

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

[0014] However, the technical problems to be solved by the present invention are not limited to the above-described problems at all, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention described below. Means for Solving the Problems

[0015] A battery module according to one aspect of the present invention for achieving the above object includes 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, and a cover member adhered to a side portion of the cell assembly where the electrode leads protrude in the internal space of the module case.

[0016] Here, at least a part of the cover member may be adhered to the electrode leads of the plurality of battery cells provided in the cell assembly.

[0017] In addition, the module case may include a main body frame having at least one of the front and the rear opened and an end plate coupled to the opened portion of the main body frame.

[0018] Furthermore, the cell assembly may be configured such that the electrode lead is positioned on the end plate side, and the cover member may be interposed between the electrode lead of the cell assembly and the end plate.

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

[0020] Furthermore, the cover member may be configured to be filled in a side portion of the cell assembly where the electrode lead protrudes.

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

[0022] Furthermore, the cover member may be filled as a whole from the upper end to the lower end in front of or behind the cell assembly.

[0023] Furthermore, the cover member may be configured such that the upper end and the lower end are bent in the direction of the cell assembly.

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

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

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

[0027] Also, a battery pack according to another aspect of the present invention for achieving the above object includes the battery module according to the present invention.

[0028] Furthermore, an automobile according to still another aspect of the present invention for achieving the above object includes a battery module according to the present invention.

Advantages 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 at a certain level or higher.

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

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

[0032] Therefore, it is possible to prevent the internal ejecta from adhering to the electrode lead due to the flames or vent gases ejected from a specific battery cell, or to prevent internal short circuits or the like from occurring due to damage or floating of the electrode lead.

[0033] Also, according to such an embodiment of the present invention, since high-temperature gases, flames, etc. do not flow into the electrode lead side of the cell assembly, it is possible to prevent the propagation of thermal runaway between the battery cells.

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

[0035] In addition to these, the present invention can have various other effects, and regarding this, it will be described in the column of each implementation configuration, or regarding effects that can be easily analogized by those skilled in the art, the description thereof will be omitted.

[0036] The drawings attached to this specification illustrate desirable embodiments of the present invention and are for the purpose of further understanding the technical idea of the present invention together with the content of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0037]

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[0038] Hereinafter, preferred embodiments 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 the claims are not to be construed as being limited to ordinary or dictionary meanings. The inventor himself interprets them according to the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that he can appropriately define the concept of the terms in order to explain the invention in the best way. Therefore, it should be understood that the embodiments described in this specification and the configurations shown 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. At the time of this application, there may be various equivalents and modifications that can replace them.

[0039] FIG. 1 is a perspective view in an assembled state schematically showing the configuration of a battery module according to an 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 in a form in which some components in the configuration of FIG. 2 are further disassembled. FIG. 4 is a front view of some components of FIG. 2.

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

[0041] The cell assembly 100 may include a plurality of battery cells 110. Here, each battery cell 110 may mean a secondary battery. The secondary battery may include an electrode assembly, an electrolyte, and a battery case. In particular, the battery cell 110 provided in the cell assembly 100 may be a pouch-type secondary battery. However, other forms of secondary batteries, that is, cylindrical batteries and square batteries, may also be adopted in the cell assembly 100 of the present invention.

[0042] A plurality of secondary batteries may form the cell assembly 100 in a stacked form with respect to each other. For example, a plurality of secondary batteries may be stacked in a shape arranged so as to be arranged side by side in the horizontal direction (the X-axis direction in the figure) in a state of being erected in the vertical direction (the Z-axis direction in the figure) respectively.

[0043] Each battery cell 110 may include an electrode lead 111. At this time, the electrode lead 111 may be located at both ends of each battery cell 110 or may be located at one end. A plurality of battery cells 110 may be electrically connected to each other in series and / or in parallel via the electrode leads 111. At this time, the electrode leads 111 of each battery cell 110 may be directly connected in contact with each other, or may be indirectly connected via a bus bar or the like. On the other hand, a secondary battery in which the electrode lead 111 protrudes in both directions is sometimes referred to as a two-way cell, and a secondary battery in which the electrode lead 111 protrudes in one direction is sometimes referred to as a one-way cell. In FIG. 2 and the like, a form in which the electrode lead 111 protrudes in both the front and the rear directions is shown. However, the present invention is not limited by such specific types and forms of secondary batteries, and various forms of secondary batteries already known at the time of filing the present invention may be adopted in the cell assembly 100 of the present invention.

[0044] As shown in FIG. 2, the module case 200 may be configured to have an internal space, that is, an empty space formed therein, to accommodate the cell assembly 100. Further, as shown in FIGS. 1 and 2, etc., the module case 200 may be configured in a rectangular parallelepiped shape. Note that the cell assembly 100 may be accommodated in such an internal space of the 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 the side portion of the cell assembly 100. Further, although the electrode lead 111 of the cell assembly 100 may be configured to protrude in a specific direction, the cover member 300 may be adhered to the side portion of the cell assembly 100 where the electrode lead 111 protrudes.

[0046] For example, referring to FIGS. 2 and 3, the cell assembly 100 may be in a form in which a plurality of battery cells 110 are stacked and may include six side portions (upper portion, lower portion, front portion, rear portion, left side portion, right side portion). At this time, the electrode leads 111 may be disposed on the cell assembly 100 in a form protruding from specific side portions of the cell assembly 100, that is, the front portion and the rear portion as shown in the drawing. At this time, the cover member 300 may be adhered to the front portion and the rear portion of the cell assembly 100 where the electrode leads 111 are located, respectively.

[0047] The cover member 300 may be composed only of an adhesive substance, or may be configured in a form in which an adhesive substance and a non-adhesive substance are provided together. Note that the cover member 300 may continue to maintain adhesiveness, or may be configured in a form in which adhesiveness is lost due to hardening of the adhesive substance in the adhered state. Here, adhesion may mean including adhesion.

[0048] According to such an implementation configuration of the present invention, it becomes possible to stably hold a portion where a plurality of electrode leads 111 are coupled and fixed to each other in the cell assembly 100. In particular, the plurality of electrode leads 111 can be coupled and fixed in a form welded to each other. However, since the cover member 300 is adhered to the cell assembly 100 at a portion where the electrode leads 111 are present, it becomes possible to stably hold the welded state of the plurality of electrode leads 111. Therefore, even if vent gas or flame occurs 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 cover member 300 can keep the welding state, position, etc. of the electrode leads 111 constant, it becomes possible to suppress the movement of the electrode leads 111 due to the ejection pressure of the vent gas or the pressure of the flame. Also, according to the above implementation configuration, even if ejecta in a form where internal components are melted is ejected from a specific battery cell 110, it is possible to block such ejecta from adhering to the electrode leads 111 toward the electrode lead 111 side. Therefore, it is possible to effectively prevent a short circuit from occurring inside the battery module, particularly on the electrode lead side, due to the movement of the electrode leads 111 or the adhesion of ejecta or the like.

[0049] Also, according to the above implementation configuration, it is possible to suppress the flow of gas, flame, ejecta, etc. ejected from the battery cell 110 in the direction where the electrode leads 111 are located. Therefore, it becomes possible to more effectively prevent the propagation of thermal runaway through the terrace portion where the electrode leads 111 are located in the cell assembly 100.

[0050] In particular, at least a part of the cover member 300 can be adhered to the electrode leads 111 of the plurality of battery cells 110 provided in the cell assembly 100.

[0051] For example, referring to what is shown in FIGS. 2 and 3, the electrode leads 111 of the plurality of battery cells 110 included in the cell assembly 100 can be connected to each other by a method such as welding. At this time, the cover member 300 can be attached in direct contact with the electrode leads 111 of at least some of the battery cells 110. Further, the cover member 300 can be adhered to all of the electrode leads 111 of the entire battery cells 110.

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

[0053] According to such an implementation configuration of the present invention, the electrode lead 111 disposed in the cell assembly 100 can be directly adhered to the cover member 300. Therefore, it is possible to more firmly prevent the ejection (such as molten particles) of the battery cell 110 from contacting the surface of the electrode lead 111, particularly the outer surface (the front surface or the rear surface). Also, in this case, it is possible to more firmly limit the movement of the electrode lead 111 due to gas, flame, etc. Therefore, it is possible to more effectively prevent the occurrence of internal short circuits, etc. on the electrode lead 111 side of the battery module.

[0054] The cover member 300 can be configured adjacent to or in contact with the electrode lead 111. Therefore, the cover member 300 can be made of a material having electrical insulation or can be provided with a material having electrical insulation. Note that since the cover member 300 is adhered to the outer surface of the electrode lead 111, it can be provided with a material having adhesiveness or tackiness. The adhesiveness or tackiness of the cover member 300 may be continuously maintained or may change according to temperature, etc.

[0055] The cover member 300 may include various resins and various phase change materials (PCMs) that were already known at the time of filing of the present invention. In particular, the cover member 300 may be made of a thermal conductive material applied to the lower part of the cell assembly 100 or the like inside the battery module, or may include such a thermal conductive material. For example, the cover member 300 may include a thermal interface material (TIM) such as thermal grease, thermal paste, or thermal compound. Note that the cover member 300 may include a fire extinguishing substance. 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 FIGS. 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 or the like from the electrode leads 111. In particular, as shown in FIG. 3, the busbar assembly 400 may include a module busbar 410 and a busbar housing 420.

[0057] Here, the module busbar 410 may be made of an electrically conductive material, that is, a metal material. Also, the module busbar 410 may be configured to electrically connect between two or more electrode leads 111 or be connected to one or more electrode leads 111 to transfer sensing information to a control unit such as a battery management system (BMS).

[0058] Also, the bus bar housing 420 can be made of an electrically insulating material, that is, a plastic material. Further, the bus bar housing 420 can be configured such that the module bus bar 410 is placed and fixed thereon. Furthermore, the bus bar housing 420 can have slits formed therein, such as the portion shown at S1 in FIG. 3. And the module bus bar 410 can be attached to the outside, that is, the front side of the bus bar housing 420. In this case, the electrode lead 111 can contact the module bus bar 410 located outside through the slit S1 of the bus bar housing 420. In particular, the electrode lead 111 can be coupled and fixed to the module bus bar 410 alone or in a state where two or more are laminated. At this time, as a method of coupling and fixing the electrode lead 111 and the module bus bar 410, methods such as laser welding or ultrasonic welding can be used, and in addition, various other fastening methods can be applied.

[0059] The cover member 300 can be attached to the electrode lead 111 with at least a part thereof located outside, that is, on the front side of the bus bar housing 420. For example, as shown in FIGS. 2 to 4, the electrode lead 111 can be configured to be stacked with the module bus bar 410 on the outside, that is, the front side of the bus bar housing 420. At this time, the cover member 300 can be adhered to the outside, that is, the front side of the electrode lead 111. In this case, the cover member 300 can also 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 can be adhered to the front surfaces of the electrode lead 111, the module bus bar 410, and the bus bar housing 420. On the other hand, although not shown, the cover member 300 can also be provided on the rear side of the cell assembly 100 and adhered to the rear surfaces of the electrode lead 111, the rear module bus bar 410, and the rear bus bar housing 420 on the rear side of the cell assembly 100.

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

[0061] Here, the terminal terminal 500 may include a positive terminal and a negative terminal. And the terminal terminal 500 is composed of a metal material having electrical conductivity such as copper or aluminum, and is connected to other components outside the battery module, so that it can function as a path through which charge and discharge current flows. Further, the connector terminal 600 can function as a path for exchanging various information and signals of the cell assembly, such as the electrical characteristics of the cell assembly 100, that is, the voltage of each battery cell 110 and the overall voltage of the cell assembly 100, with a control component such as a battery management system (BMS). Such terminal terminals 500 and connector terminals 600 are components widely provided in the battery module, and detailed description thereof will be omitted.

[0062] As shown in FIG. 3 and the like, the terminal terminal 500 and the connector terminal 600 may be located in the bus bar housing 420. However, the present invention is not necessarily limited to such a form, and the terminal terminal 500 and the connector terminal 600 may be located in other parts other than the bus bar housing 420.

[0063] In such an implementation configuration, the cover member 300 may not be adhered to the terminal terminal 500 or the connector terminal 600. That is, the cover member 300 is mainly adhered to a portion other than the terminal terminal 500 and the connector terminal 600, and may be configured such that at least a part of each of the terminal terminal 500 and the connector terminal 600 is exposed to the outside.

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

[0065] Here, the main body frame 210 can be configured in a form where at least one of the front and the rear is open. In particular, as shown in FIG. 2, the main body frame 210 can be configured in a form where the upper, lower, left, and right sides are closed and the front and the rear are open. At this time, the upper, lower, left, and right sides can each be configured in a plate shape, and these four plates can be manufactured into an integrated tubular shape. And such a main body frame 210 with such a shape can be named a monoframe. That is, the main body frame 210 includes an upper plate, a lower plate, a left plate, and a right plate, and an internal space can be defined by these plates. Note that the cell assembly 100 can be accommodated in the internal space of the main body frame 210 defined in this way.

[0066] And the end plate 220 can be configured to be coupled to the open portion of the main body frame 210. For example, as shown in FIGS. 1 and 2, when the main body frame 210 is configured in a monoframe shape with the front and the rear open, the end plate 220 can be respectively disposed in front of and behind the main body frame 210 and coupled to the front open portion and the rear open portion of the main body frame 210 respectively. In this case, the front and the rear of the internal space of the main body frame 210 are defined by the end plate 220, and the internal space can be closed as a whole.

[0067] In such an implementation configuration, the cell assembly 100 can be configured such that the electrode leads 111 of each battery cell 110 are located on the end plate 220 side. That is, referring to what is shown in FIG. 2, each of the plurality of battery cells 110 provided in the cell assembly 100 can be a pouch-type secondary battery and can be configured in a form standing in the vertical direction. That is, the wide surface of the accommodating portion of each battery cell 110 faces in the left-right direction, and the seal portion surrounding the accommodating portion in each battery cell 110 can be located above, below, in front of, and behind the accommodating portion. And the electrode lead 111 can be located on the front side and the rear side of each battery cell 110. Note that the plurality of battery cells 110 can be arranged 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 in the seal portion of each battery cell 110 is located on the front side and the rear side.

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

[0069] According to such an implementation configuration, it is possible to suppress vent gas, flames, etc. discharged from a specific battery cell 110 from heading toward the end plate 220. Further, since the cover member 300 adhered 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 ejectant, i.e., an injection cover, etc., which was conventionally included in the battery module. In other words, conventionally, an injection cover physically separated from these for electrical insulation, etc. was required between the electrode lead 111 and the end plate 220. In addition, when such an injection cover melted due to flames or gas, it adhered to the electrode lead, etc. and caused internal short circuits, etc. However, according to the above implementation configuration of the present invention, since the insulating cover adhered to the electrode lead 111 is interposed between the electrode lead 111 and the end plate 220, it becomes possible to remove the conventional injection cover.

[0070] In the above implementation configuration, the main body frame 210 can be made of a metal material such as aluminum or stainless steel (SUS: stainless steel). Also, the end plate 220 can be made of a metal material in the same manner as the main body frame 210. In particular, the end plate 220 can be made of the same material as the main body frame 210. According to the present invention, since it is possible to attach a cover member 300 made of an electrically insulating material outside 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 part of the module case 200 can be provided with a non-metal material such as plastic.

[0071] The cover member 300 can be configured in a film shape. In particular, the cover member 300 is made of a polymer material and includes a base material layer having a thin sheet shape. However, it can be configured in a form in which an adhesive layer is disposed on at least one surface of such a base material layer, that is, the inner surface. 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, it can be configured in a form in which an adhesive substance is applied to the rear surface of the base material layer.

[0072] Here, the cover member 300 can have a thickness as thin as 0.5 mm to 1 mm. However, the thickness of such a cover member 300 can be appropriately designed in other forms according to various situations and conditions such as the type, form, size of the battery cell 110, and the material of the cover member 300.

[0073] Also, the cover member 300 can be configured in a form that is bent so as to wrap around the outside of the cell assembly 100. For example, like the portions indicated by A2 and A2' in FIGS. 2 and 3, the cover member 300 can be configured in a form in which both horizontal ends are bent. And such bent portions can be bent toward the outer surfaces of the two battery cells 110 located on the outermost side of the cell assembly 100 stacked in the horizontal direction. In particular, the bent portions at both horizontal ends of the cover member 300 can be adhered to the outside of the cell assembly 100. That is, in FIGS. 2 and 3, the left bent portion and the right bent portion of the cover member 300 like the portions indicated by A2 and A2' can be adhered to the left surface and the right surface of the cell assembly 100, respectively.

[0074] According to such an implementation configuration of the present invention, the bonding force between the cover member 300 and the cell assembly 100 can be improved, and even when vent gas or a flame occurs, the position and shape of the cover member 300 can be prevented from being deformed. Therefore, the protective effect of the cover member 300 on the electrode lead 111 is further improved. Also, according to the above implementation configuration, by narrowing or removing the interval between the cover member 300 and the cell assembly 100, the movement of vent gas or a flame to the front side and the rear side of the cell assembly 100 can be more effectively suppressed.

[0075] The cover member 300 can be configured in a form filled in the side portion where the electrode lead 111 protrudes in the cell assembly 100. This will be described in more detail with further reference to FIGS. 5 to 7 and the like.

[0076] FIG. 5 is a partial perspective view schematically showing 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. Further, FIG. 7 is a cross-sectional view taken along the line A3 - A3' of FIG. 5. On the other hand, for various embodiments included in this specification including this embodiment, detailed descriptions will be omitted for parts where descriptions of other embodiments are equally or similarly applicable, and descriptions will focus on parts where there are differences.

[0077] Referring to FIGS. 5 to 7, the cell assembly 100 can be configured in a form in which the electrode lead 111 protrudes from the front side portion. And in the front side portion of such a cell assembly 100, the module case 200, particularly, the end plate 220 can be located. In such a configuration, the cover member 300 can be configured in a form filled and adhered to the front side portion of the cell assembly 100.

[0078] For example, the cover member 300 can be configured to fill at least a part of the space between the side portion in front of the cell assembly 100 and the end plate 220. At this time, the cover member 300 can be first injected or applied as an adhesive having viscosity and fluidity, filled in at least a part of the space between the side portion in front of the cell assembly 100 and the end plate 220, and then configured in a hardened form. As another example, the cover member 300 can be configured to continue to have viscosity or fluidity without hardening after being injected or applied to the side portion in front of the cell assembly 100.

[0079] In particular, the cover member 300 can be filled between the seal portions of adjacent battery cells 110. This will be described in more detail with further reference to FIG. 8.

[0080] FIG. 8 is a diagram showing an enlarged view of the portion A4 in FIG. 7.

[0081] Referring to FIG. 8, the electrode leads 111 of each battery cell 110 included in the cell assembly 100 can protrude forward. At this time, each battery cell 110 can have a seal portion in a form in which the electrode lead 111 is interposed, and as shown at T, the terrace portion can be located on the front side. And between the seal portions of each battery cell 110, that is, between the terrace portions T of each battery cell 110, a free space can be formed like the portion shown at A5. At this time, the cover member 300 can be filled in the space between the seal portions of adjacent battery cells 110, that is, in the space between the terrace portions of adjacent battery cells 110.

[0082] Also, when described with reference to one seal portion (terrace portion), the cover member 300 can be filled on the left side and the right side of each seal portion. Although not shown in FIG. 8, the cover member 300 can also be filled on the upper and lower portions of each seal portion. In this case, it can be said that the cover member 300 is configured to wrap all of the upper, lower, left, and right portions with respect to the seal portion (terrace portion).

[0083] According to such a configuration of the present invention, when the internal pressure increases in a specific battery cell 110 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 flame from being directly ejected or exposed to the end plate 220 side. In addition, according to the above-described implementation configuration, since the cover member 300 firmly prevents the terrace portion from floating, the movement of the electrode lead 111 located on the terrace portion can be restricted.

[0084] In particular, the cover member 300 may be located in front of and / or behind the cell assembly 100 and may be configured to be filled as a whole from the upper end to the lower end.

[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, the filling components between the terrace portions such as the portion indicated by A5 in FIG. 8 may be configured to extend in a long shape 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 end and the lower end are bent in the direction of the cell assembly 100. That is, the cover member 300 may be filled up to the surface of the upper end of the cell assembly 100 and have a shape bent to the surface of the upper end of the cell assembly 100 as shown in the portion indicated by B1 in FIG. 5. At this time, the cover member 300 may be adhered to the upper surface of the cell assembly 100. In addition, 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] Further, the cover member 300 can be filled up to the surface of the lower end of the cell assembly 100 and have a shape bent on the surface of the lower end of the cell assembly 100, like the portion shown at B2 in FIG. 5. At this time, the cover member 300 can be adhered to the lower surface of the cell assembly 100. Note that the cover member 300 can be interposed between the lower surface of the cell assembly 100 and the inner surface (upper surface) of the module case 200.

[0088] According to such an embodiment configuration of the present invention, it is possible to more firmly suppress the movement of vent gas, flame, etc. to the electrode lead 111 side of the cell assembly 100. That is, in the case of the above-described embodiment configuration, the space between the front side portion and / or the rear side portion of the cell assembly 100 and the end plate 220 becomes narrow. Further, the cover member 300 can prevent vent gas, flame, etc. discharged to the central portion of the upper end or the central portion of the lower end of the cell assembly 100 from moving to the end plate 220 side. Therefore, according to such an embodiment configuration, it is possible to more effectively prevent various problems caused by the movement of flame and vent gas to the portion where the electrode lead 111 is located and the end plate 220 side.

[0089] Moreover, according to such an embodiment configuration, the bonding property between the cover member 300 and the cell assembly 100 is further improved. Note that according to the above-described embodiment configuration, the electrode lead 111 of the battery cell 110 can be more firmly protected by the cover member 300.

[0090] Further, the cover member 300 can be filled horizontally between the main body of each battery cell 110 and the bus bar assembly 400. For example, referring to what is shown in FIG. 8, in each battery cell 110, the housing portion in which the electrode assembly is accommodated and the bus bar assembly 400 can be arranged to be separated from each other by a predetermined distance in the front-rear direction (the Y-axis direction in the figure). At this time, the cover member 300 can be filled in a form interposed between such a housing portion of the battery cell 110 and the bus bar assembly 400, particularly, between the bus bar housing 420. In this case, it can be said that the cover member 300 is filled (positioned) between the housing portion of each battery cell 110 and the electrode lead 111.

[0091] The cover member 300 may be located outside the electrode lead 111 in the horizontal direction. This will be described in more detail with further reference to FIG. 9 together with FIG. 7.

[0092] FIG. 9 is an enlarged view of the portion A6 in FIG. 7.

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

[0094] In this case, it becomes possible to prevent the electrode lead 111 from being exposed to the outside by the cover member 300. Further, an end plate 220 can be positioned outside the electrode lead 111. Therefore, according to the above-described embodiment configuration, it becomes possible for the cover member 300 to be interposed between the electrode lead 111 and the end plate 220. Therefore, when the cover member 300 is made of a material having electrical insulation properties, even if the end plate 220 is made of a metal material, it becomes possible to prevent an electrical short between the electrode lead 111 and the end plate 220.

[0095] Also, the cover member 300 can be interposed between the electrode leads 111. For example, as in the portion shown at A8 in FIG. 9, adjacent electrode leads 111 can be separated from each other. At this time, the cover member 300 can be filled between the electrode leads 111. According to such an embodiment configuration, it becomes possible to more firmly prevent the movement of the electrode leads 111 and their unintended mutual contact.

[0096] Furthermore, in the above-described embodiment configuration, the cover member 300 can be positioned outside the bus bar assembly 400. That is, referring to the embodiment configuration of FIG. 9, the cover member 300 can be positioned on the front side (-Y-axis direction side) of the bus bar assembly 400.

[0097] Furthermore, the cover member 300 can be configured to be filled both inside and outside the bus bar assembly 400. For example, as shown in FIGS. 7 to 9, the cover member 300 can be filled both inside (rear side) and outside (front side) of the bus bar assembly 400.

[0098] According to such an implementation configuration of the present invention, the bus bar assembly 400 with the electrode lead 111 welded and fixed can be firmly protected and fixed by the cover member 300. In particular, the bus bar housing 420 can be formed of a plastic material, but it can further firmly prevent such a bus bar housing 420 from being damaged or melted by a flame or high-temperature vent gas. Also, in this case, by disposing (filling) the cover member 300 around the bus bar assembly 400, it is possible to narrow the empty space of the portion where the bus bar assembly 400 is located. 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 ensured.

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

[0100] In particular, when the cover member 300 is configured to be filled on the side portion of the cell assembly 100, a fluid adhesive substance for forming the cover member 300 can be injected into the inside of the module case 200 in a state where the cell assembly 100 is accommodated. At this time, when the fluid adhesive substance is injected both in front of and behind the bus bar assembly 400, it can be configured such that the adhesive substance is not filled around the terminal terminal 500 and the connector terminal 600 provided on the upper portion of the bus bar assembly 400, particularly on the upper portion. For example, the bus bar housing 420 can be provided with a guide structure such as a partition wall so that the adhesive substance for the cover member 300 does not flow around the terminal terminal 500 and the connector terminal 600.

[0101] In addition to this, various structures and manufacturing methods can be applied to expose the terminal terminal 500 and the connector terminal 600 to the outside without being completely wrapped by the cover member 300.

[0102] The cover member 300 can be configured to cover the entire length from the upper end to the lower end of the electrode leads 111 of the plurality of battery cells 110.

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

[0104] In particular, the cover member 300 can be configured to completely cover the entire electrode lead 111 provided in the cell assembly 100 in the vertical direction. That is, the cover member 300 can be configured to cover the electrode lead 111 as a whole. For example, in the case of the cover member 300 provided on the front side of the cell assembly 100 as shown in FIGS. 2, 4, and 5, the outer surface of the entire electrode lead 111 located on the front side in the cell assembly 100, that is, the front side surface can be configured not to be 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 can be completely wrapped by the cover member 300 and not be exposed to the outside.

[0105] According to such an implementation configuration of the present invention, the outside of the electrode lead 111, that is, the front side, can be more firmly protected and fixed by the cover member 300. Therefore, it is possible to more effectively prevent foreign substances such as molten particles from adhering to the outside of the electrode lead 111 and the electrode lead 111 from moving. Further, as shown in various previous drawings, when a plurality of battery cells 110 are stacked in the left-right direction, the vent gas and flame generated in a specific battery cell 110 are likely to flow into the electrode lead 111 side from the upper and lower sides. Therefore, if the cover member 300 covers all of the electrode lead 111 from the upper end to the lower end as in the above implementation configuration, the protection effect on the electrode lead 111 is further improved.

[0106] FIG. 10 is a diagram schematically showing some components of a battery module according to still another embodiment of the present invention in an exploded manner. Further, FIG. 11 is a diagram schematically showing the cross-sectional configuration of the battery module of FIG. 10 in a coupled state. For example, FIG. 11 schematically shows the form of a cross-section taken along the line A9 - A9' in the configuration in which the battery module of FIG. 10 is coupled.

[0107] Referring to FIGS. 10 and 11, a vent hole can be formed in the module case 200 as indicated by H. The vent hole H can be configured to penetrate the module case 200. In such a 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 can be discharged to the outside of the module case 200 through the vent hole H.

[0108] In particular, as shown in the various drawings described above, the cell assembly 100 can be configured such that a plurality of battery cells 110 are stacked in the left - right direction inside the module case 200. At this time, the vent hole H can 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 can be formed in such an upper plate or lower plate. Further, as shown in FIG. 10, the vent hole H can be configured to extend in a long shape in the left - right direction, which is the stacking direction of the battery cells 110, in the upper plate or the lower plate.

[0109] According to such an embodiment of the present invention, vent gas, flame, 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 of preventing vent gas, flame, etc. from reaching the electrode leads 111 located on the front side and the rear side of the cell assembly 100 by the cover member 300 is further improved.

[0110] Furthermore, as in the above - described embodiment, when the front side and the rear side of each battery cell 110, that is, the terrace part side, are adhered by the cover member 300 in a state where a plurality of battery cells 110 are arranged in the left - right direction, the vent gas can be discharged from each battery cell 110 in the upward or downward direction. 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 etc. can easily go toward the vent hole H without going toward the electrode lead 111 side.

[0111] Thus, in the embodiment configuration in which the vent hole H is provided in the module case 200, the battery module according to the present invention may further include a vent unit 700 as shown in FIGS. 10 and 11.

[0112] The vent unit 700 may be arranged on at least one side of the module case 200 and configured such that vent gas can move. In particular, the vent unit 700 may be arranged outside the module case 200. Further, the vent unit 700 may be configured to be attached to at least the 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 upper part, the vent unit 700 may be attached to the upper part of the module case 200.

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

[0114] According to such an implementation configuration of the present invention, by controlling the path of the vent gas discharged from the module case 200 of the battery module, such as the discharge direction and position, damage to the user and other devices caused by the high-temperature vent gas can be removed or reduced. Further, according to the above implementation configuration, through the vent unit 700, the discharge path of the vent gas is bent, so that fire inducing factors such as flames and sparks can be more effectively suppressed from being discharged outside the battery module. In this case, various forms of blocking structures for blocking substances such as flames and sparks can be provided inside the vent unit 700. Moreover, according to such an implementation configuration of the present invention, the normal configuration of the battery module, that is, the structure of the module case 200 and the cell assembly 100 provided therein, etc., do not change significantly, and it is only necessary to attach or weld the vent unit 700 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 diagram schematically showing a partial component of a battery module according to still another embodiment of the present invention in an exploded manner. Further, FIG. 13 is a perspective view of the configuration of the battery module including the components of FIG. 12 as viewed from below. Note that FIG. 14 is a cross-sectional view taken along the line A10-A10' of FIG. 13. For this embodiment, the description will focus on the parts that are different from the above-described embodiments.

[0116] Referring to FIGS. 12 to 14, the cover member 300 may be in substantially the same form as FIG. 5 and may be configured to cover the side surface of the cell assembly 100, particularly the front side and / or the 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 not to completely adhere to and cover the entire side portion of the cell assembly 100, but to adhere to and cover only a part of the side portion of the cell assembly 100.

[0117] More specifically, as shown by the portion indicated as B3 in FIGS. 12 and 14, the cover member 300 may be configured not to cover the lower portion of the side of the cell assembly 100. Further, as shown in FIGS. 12 and 14, 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-rear direction, Y-axis direction). In this case, it can be said that the cover member 300 is configured to cover the outer side in the horizontal direction of the cell assembly 100 but to be open without covering in the lower direction.

[0118] According to such an implementation configuration, it becomes possible to control vent gas or the like through the portion not covered by the cover member 300, that is, the portion of B3. That is, when vent gas, flame, or the like is generated from the cell assembly 100, such vent gas or the like can be guided in the lower direction as indicated by the arrow in FIG. 14.

[0119] At this time, vent holes may be formed on the lower side of the module case 200 as shown by the portion indicated as H’ in FIGS. 13 and 14. And such vent holes H’ may be provided at positions communicating with the uncovered portion (unfilled portion) B3 of the cover member 300 as shown in FIG. 14. Further, such an embodiment can be more effectively applied in an implementation configuration in which a battery module is placed on a pack case, when a component for guiding vent gas or the like is provided on the portion of the pack case in contact with the lower side of the battery module, that is, on the bottom surface side of the pack case.

[0120] According to such an implementation configuration of the present invention, it becomes easier to realize the configuration of directional venting in which vent gas, flame, or the like formed inside the battery module is guided in a specific direction of the battery module, that is, the lower side. Further, according to the above implementation configuration, it is possible to more firmly prevent vent gas, flame, or the like from heading toward the module terminal side located on the upper side in 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 configuration shown in FIGS. 12 to 14, the cover member 300 is arranged in a form filled as a whole on the front and rear sides of the cell assembly 100, but in the portion of B3, the filling amount of the cover member 300 may be configured to be less than that of other portions. In this case, vent gas or the like can be guided to the portion where the filling amount of the cover member 300 is less.

[0122] On the other hand, in the embodiment configuration shown in FIGS. 12 to 14, an embodiment is shown in which vent gas is guided to the lower side of the battery module, but an embodiment in which vent gas is guided to the other side of the battery module, that is, the upper side, can also be prepared.

[0123] The battery pack according to the present invention may include one or more of the battery modules according to the present invention described above. Further, the battery pack according to the present invention may further include various other components in addition to such a battery module, that is, components of a battery pack known at the time of filing of the present invention, such as a battery management system (BMS), a bus bar, a pack case, a relay, a current sensor, and the like.

[0124] The battery module according to the present invention can be applied to automobiles such as electric vehicles and hybrid vehicles. 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. Further, the automobile according to the present invention may further include various other components included in the automobile in addition to such a 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] In addition, the battery module according to the present invention can be applied to an energy storage system (ESS). That is, 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] On the other hand, in this specification, directional terms such as up, down, left, right, front, and back are used, but these terms are only used for ease of explanation and may vary depending on the position of the object in question and the position of the observer, etc. This is self-evident to those skilled in the art of the present invention.

[0127] As described above, the present invention has been described with reference to limited embodiments and drawings, but the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made within the equivalent scope of the technical idea and claims of the present invention by those having ordinary knowledge in the technical field to which the present invention pertains.

Description of Reference Numerals

[0128] 100 Cell Assembly 110 Battery Cell 111 Electrode Lead 200 Module Case 210 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 comprising a plurality of battery cells electrically connected to each other via electrode leads; A module case for housing the cell assembly in an internal space; A cover member adhered to a side portion of the cell assembly where the electrode leads protrude in the internal space of the module case; A battery module including the above.

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

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

4. In the cell assembly, the electrode leads are positioned on the end plate side, The battery module according to Claim 3, wherein the cover member is interposed between the electrode leads of the cell assembly and the end plate.

5. The battery module according to Claim 1, wherein the cover member is formed in a film shape having an adhesive layer on the surface of a base material layer.

6. The battery module according to Claim 1, wherein the cover member is configured to be filled in a side portion of the cell assembly where the electrode leads protrude.

7. The battery module according to Claim 6, wherein the cover member is filled between the seal portions of adjacent battery cells.

8. The battery module according to Claim 6, wherein the cover member is filled as a whole from the upper end to the lower end in front of or behind the cell assembly.

9. The battery module according to Claim 8, wherein the upper end and the lower end of the cover member are bent in the direction of the cell assembly.

10. The battery module according to Claim 1, wherein the cover member covers the electrode leads of the plurality of battery cells as a whole from the upper end to the lower end.

11. The battery module according to Claim 1, wherein vent holes are formed in at least one of the upper and lower portions of the module case.

12. The battery module according to claim 11, further comprising a vent unit disposed outside a portion where a vent hole is formed in the module case and through which vent gas discharged from the vent hole can move.

13. A battery pack including the battery module according to any one of claims 1 to 12.

14. An automobile including the battery module according to any one of claims 1 to 12.

Images