Battery module and battery pack including the same

Abstract

A battery module according to an embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module frame that houses the battery cell stack, and end plates that cover front and rear surfaces of the battery cell stack. At least one of the module frame and the end plates includes a vent for exhausting gas and flame. The vent is shaped to guide the exhaust path of the gas and flame so as to bend.

Description

Technical Field

[0001] [Cross - References to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2021 - 0005833 filed on January 15, 2021 and Korean Patent Application No. 10 - 2022 - 0000798 filed on January 4, 2022, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference.

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

Background Art

[0003] In modern society, as the use of portable devices such as mobile phones, notebook computers, camcorders, and digital cameras has become common, the development of technologies in fields related to such mobile devices has been actively promoted. In addition, rechargeable secondary batteries are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug - in hybrid electric vehicles (P - HEVs), etc. as a solution to problems such as air pollution caused by existing gasoline vehicles that use fossil fuels. Therefore, the need for the development of secondary batteries is increasing.

[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 have attracted attention because they have almost no memory effect compared to nickel - based secondary batteries, can be freely charged and discharged, have a very low self - discharge rate, and have a high energy density.

[0005] Such a lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with such a positive electrode active material and a negative electrode active material, are arranged with a separator interposed therebetween, and a battery case that hermetically houses the electrode assembly together with an electrolytic solution.

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

[0007] In the case of a secondary battery used for a small device, 2 to 3 battery cells are arranged. In the case of a secondary battery used for a medium to large device such as an automobile, a battery module in which a large number of battery cells are electrically connected is used. In such a battery module, the capacity and output are improved by connecting a large number of battery cells in series or in parallel to form a battery cell laminate. One or more battery modules can be attached together with various control and protection systems such as a BDU (Battery Disconnect Unit), a BMS (Battery Management System), and a cooling system to form a battery pack.

[0008] FIG. 1 is a perspective view showing a conventional battery module.

[0009] Referring to FIG. 1, a conventional battery module 10 can be manufactured by housing a battery cell laminate (not shown) in a module frame 20 and then joining an end plate 40 to an open portion of the module frame 20. At this time, a terminal bus bar opening 41H for exposing a part of the terminal bus bar and a module connector opening 42H for exposing a part of the module connector can be formed in the end plate 40. The terminal bus bar opening 41H is for guiding the HV (High voltage) connection of the battery module 10, and the terminal bus bar exposed through the terminal bus bar opening 41H can be connected to other battery modules or a BDU (Battery Disconnect Unit). The module connector opening 42H is for guiding the LV (Low voltage) connection of the battery module 10, and the module connector exposed through the module connector opening 42H can be connected to a BMS (Battery Management System) to transmit voltage information, temperature information, etc. of the battery cells.

[0010] FIG. 2 is a view showing the state of ignition of the battery module in a conventional battery pack to which the battery module of FIG. 1 is attached. FIG. 3 is a cross-section taken along the cutting line I-I' of FIG. 2, and is a cross-sectional view showing the state of the flame affecting the adjacent battery module during the ignition of the conventional battery module.

[0011] Referring to FIGS. 1 to 3, the conventional battery module 10 includes a battery cell laminate in which a plurality of battery cells 11 are stacked, a module frame 20 that houses the battery cell laminate, and end plates 40 formed on the front and rear surfaces of the battery cell laminate.

[0012] When physical, thermal, and electrical damage occurs to the battery cells, including overcharging, and the internal pressure of the battery cell 11 increases and exceeds the limit value of the fusion strength of the battery cell 11, the high-temperature heat, gas, and flame generated in the battery cell 11 can be discharged to the outside of the battery cell 11.

[0013] At this time, the high-temperature heat, gas, and flame are discharged through the openings 41H and 42H formed in the end plate 40. However, in a battery pack structure where a plurality of battery modules 10 are arranged such that the end plates 40 face each other, the high-temperature heat, gas, flame, etc. ejected from the battery module 10 may affect the adjacent battery module 10. Therefore, there is a risk that the terminal bus bars and the like formed on the end plates 40 of the adjacent battery modules may be damaged, and the high-temperature heat, gas, and flame may enter the inside of the battery module 10 through the openings formed in the end plates 40 of the adjacent battery modules 10 and damage other electrical components including the plurality of battery cells 11. Moreover, this leads to heat propagation of the adjacent battery module 10 and causes a chain reaction of ignition in the battery pack.

[0014] Therefore, when thermal propagation occurs in the battery module, there is a need for the development of a technology that can control the high-temperature flame so as to minimize the influence on adjacent battery modules.

Summary of the Invention

Problems to be Solved by the Invention

[0015] The problem to be solved by the present invention is to provide a battery module capable of controlling the discharge path of a flame and a battery pack including the same when an ignition phenomenon occurs in the battery module.

[0016] However, the problems to be solved by the embodiments of the present invention are not limited to the above-described problems, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0017] A battery module according to an embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module frame that houses the battery cell stack, and end plates that cover the front and rear surfaces of the battery cell stack. At least one of the module frame and the end plates includes a venting portion for discharging gas and flame. The venting portion is configured to guide the discharge path of the gas and the flame to bend.

[0018] The venting portion may include a through-hole formed in at least one of the module frame or the end plate, a first cover portion that covers the through-hole, and a first opening portion formed on one side of the first cover portion and communicating with the through-hole.

[0019] The area of the first cover portion may be larger than the opening area of the through-hole.

[0020] The opening direction of the through-hole and the opening direction of the first opening portion may be different.

[0021] The opening direction of the through-hole and the opening direction of the first opening portion may be perpendicular to each other.

[0022] The venting portion may further include a second cover portion that covers the through-hole in a state of being located on the opposite side of the first cover portion with respect to the through-hole, and a second opening portion formed on one side of the second cover portion and communicating with the through-hole.

[0023] The area of the second cover portion may be larger than the opening area of the through-hole.

[0024] The opening direction of the through-hole and the opening direction of the second opening portion may be different.

[0025] The opening direction of the through-hole and the opening direction of the second opening portion may be perpendicular to each other.

[0026] The exhaust path of the gas and the flame can be bent at least twice by the first cover part and the second cover part.

[0027] The bending part can guide the exhaust of the gas and the flame in a direction parallel to at least one surface of the module frame or the end plate.

[0028] The battery module may further include an insulating cover located between the battery cell laminate and the end plate. The bending part may be formed on the end plate, and an insulating cover opening may be formed at a position corresponding to the bending part of the insulating cover.

Advantages of the Invention

[0029] According to an embodiment of the present invention, by realizing that the exhaust path of the flame generated in the battery module does not become straight, the flame exhaust can be effectively regulated without affecting the gas exhaust function.

[0030] Also, considering the nature of the flame with strong straightness, it is possible to prevent directly damaging adjacent battery modules by making the exhaust path of the flame not straight.

[0031] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Brief Description of the Drawings

[0032]

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Mode for Carrying Out the Invention

[0033] Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement it. The present invention can be realized in various different forms and is not limited to the embodiments described herein.

[0034] In order to clearly explain the present invention, parts not related to the explanation are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

[0035] Also, the sizes and thicknesses of the respective configurations shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to what is shown. The thicknesses are exaggerated in the drawings to clearly represent a plurality of layers and regions. And in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0036] Also, when a part such as a layer, film, region, or plate is “on” or “above” another part, this includes not only the case where it is “immediately above” the other part but also the case where there are other parts in between. Conversely, when a part is “immediately above” another part, it means that there are no other parts in between. Also, being “on” or “above” a reference part means being located above or below the reference part, and does not necessarily mean being located “on” or “above” in the opposite direction of gravity.

[0037] Also, throughout the specification, when a part “includes” a certain component, this means that it can further include other components, rather than excluding other components, unless otherwise stated to the contrary.

[0038] Also, throughout the specification, when it is said “on a plane”, this means when the target part is viewed from above, and when it is said “in a cross-section”, this means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0039] FIG. 4 is a perspective view showing a battery module according to an embodiment of the present invention. FIG. 5 is an exploded perspective view of the battery module of FIG. 4. FIG. 6 is a perspective view showing a battery cell included in the battery module of FIG. 5.

[0040] Referring to FIGS. 4 to 6, a battery module 100a according to an embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, a module frame 200 that houses the battery cell stack 120, and end plates 410 and 420 that cover the front and rear surfaces of the battery cell stack 120.

[0041] First, referring to FIG. 6, the battery cell 110 is preferably a pouch-type battery cell. For example, the battery cell 110 according to the present embodiment has a structure in which two electrode leads 111 and 112 protrude from one end portion 114a and the other end portion 114b of the cell body 113 so as to face each other. More specifically, the electrode leads 111 and 112 are connected to an electrode assembly (not shown) and protrude outside the battery cell 110 from the electrode assembly (not shown).

[0042] On the other hand, the battery cell 110 can be manufactured by bonding both end portions 114a and 114b of the cell case 114 and one side portion 114c connecting them in a state where an electrode assembly (not shown) is housed in the cell case 114. In other words, the battery cell 110 according to the present embodiment has a total of three sealing portions 114sa, 114sb, and 114sc, and the sealing portions 114sa, 114sb, and 114sc are sealed by a method such as heat fusion, and the remaining other side portion is a connecting portion 115. The cell case 114 is made of a laminate sheet including a resin layer and a metal layer.

[0043] In addition, the connecting portion 115 can extend long along one edge of the battery cell 110, and a protruding portion 110p of the battery cell 110 called a bat-ear can be formed at the end of the connecting portion 115. Also, the cell case 114 can be sealed with the protruding electrode leads 111, 112 interposed therebetween, and a Terrace portion 116 can be formed between the electrode leads 111, 112 and the cell body 113. That is, the battery cell 110 includes a Terrace portion 116 formed to extend from the cell case 114 in the direction in which the electrode leads 111, 112 protrude.

[0044] A plurality of battery cells 110 can be configured, and the plurality of battery cells 110 can be stacked so as to be electrically connected to each other to form a battery cell stack 120. Referring to FIG. 5, the battery cells 110 can be stacked along the y-axis direction to form a battery cell stack 120. A first bus bar frame 310 can be positioned on one surface of the battery cell stack 120 in the direction in which the electrode lead 111 protrudes (x-axis direction). Although not specifically shown, a second bus bar frame can be positioned on the other surface of the battery cell stack 120 in the direction in which the other electrode lead 112 protrudes (-x-axis direction). The battery cell stack 120 and the first bus bar frame 310 can be accommodated together in the module frame 200. The module frame 200 can protect the battery cell stack 120 accommodated inside the module frame 200 and the electrical components connected thereto from external physical impacts.

[0045] On one side, the module frame 200 can be opened in the direction in which the electrode leads 111 and 112 protrude (the x-axis direction and the -x-axis direction), and end plates 410 and 420 can be respectively positioned on both opened sides of such a module frame 200. The two end plates 410 and 420 are respectively referred to as the first end plate 410 and the second end plate 420. The first end plate 410 can cover the first bus bar frame 310 and be joined to the module frame 200, and the second end plate 420 can be joined to the module frame 200 by covering a second bus bar frame (not shown). That is, the first bus bar frame 310 can be positioned between the first end plate 410 and the battery cell stack 120, and a second bus bar frame (not shown) can be positioned between the second end plate 420 and the battery cell stack 120. Also, an insulating cover (see 800, FIG. 4) for electrical insulation can be positioned between the first end plate 410 and the first bus bar frame 310.

[0046] The first end plate 410 and the second end plate 420 are positioned so as to respectively cover the one surface and the other surface of the battery cell stack 120. The first end plate 410 and the second end plate 420 can protect the first bus bar frame 310 and various electrical components connected thereto from external impacts, and for this purpose, they should have a predetermined strength and can include a metal such as aluminum. Also, the first end plate 410 and the second end plate 420 can be joined to the corresponding edges of the module frame 200 by a method such as welding.

[0047] The first bus bar frame 310 is located on one side of the battery cell stack 120, can cover the battery cell stack 120, and at the same time can guide the connection between the battery cell stack 120 and external devices. Specifically, at least one of a bus bar, a terminal bus bar, and a module connector is attached to the first bus bar frame 310. In particular, at least one of a bus bar, a terminal bus bar, and a module connector is attached to the opposite surface of the first bus bar frame 310 that faces the battery cell stack. As an example, FIG. 5 shows a state in which a bus bar 510 and a terminal bus bar 520 are attached to the first bus bar frame 310.

[0048] After the electrode lead 111 of the battery cell 110 passes through the slit formed in the first bus bar frame 310, it can bend and be joined to the bus bar 510 or the terminal bus bar 520. The battery cells 110 constituting the battery cell stack 120 can be connected in series or in parallel by the bus bar 510 or the terminal bus bar 520. Also, the battery cell 110 can be electrically connected to an external device or a circuit by the terminal bus bar 520 exposed outside the battery module 100a.

[0049] The first bus bar frame 310 can include a material that is electrically insulating. The first bus bar frame 310 can limit the contact between the bus bar 510 or the terminal bus bar 520 and the battery cell 110, except for the portion where the bus bar 510 or the terminal bus bar 520 is joined to the electrode lead 111, and can prevent the occurrence of a short circuit.

[0050] On the other hand, as described above, a second bus bar frame can be located on the other side of the battery cell stack 120, and at least one of a bus bar, a terminal bus bar, or a module connector is attached to the second bus bar frame. The electrode lead 112 can be joined to such a bus bar.

[0051] In the first end plate 410 according to the present embodiment, an opening for exposing at least one of a terminal bus bar or a module connector can be formed. The opening can be a terminal bus bar opening or a module connector opening. As an example, as shown in FIGS. 4 and 5, in the first end plate 410, a terminal bus bar opening 410H for exposing the terminal bus bar 520 can be formed. The terminal bus bar 520 further includes a portion protruding upward as compared with the bus bar 510, and such a portion protruding upward can be exposed to the outside of the battery module 100a through the terminal bus bar opening 410H. The terminal bus bar 520 exposed through the terminal bus bar opening 410H can be connected to other battery modules or a BDU (Battery Disconnect Unit) to form an HV (High voltage) connection.

[0052] FIG. 7 is a perspective view showing the second end plate of the battery module in FIG. 4 at a different angle so as to be viewed from the front.

[0053] Referring to FIG. 7, as an example, in the second end plate 420, a module connector opening 420H for exposing the module connector 600 can be formed. This means that the module connector 600 is attached to the second bus bar frame mentioned above. The module connector 600 can be connected to a temperature sensor, a voltage measurement member, etc. provided inside the battery module 100a. Such a module connector 600 is connected to an external BMS (Battery Management System) to form an LV (Low voltage) connection, and is responsible for the function of transmitting temperature information, voltage levels, etc. measured by the temperature sensor and the voltage measurement member to the external BMS.

[0054] The first end plate 410 and the second end plate 420 shown in FIGS. 4, 5, and 7 are exemplary structures, and in other embodiments of the present invention, a module connector is attached to the first bus bar frame 310 and a terminal bus bar is attached to the second bus bar frame. Therefore, a module connector opening can be formed in the first end plate, and a terminal bus bar opening can be formed in the second end plate.

[0055] On the other hand, the end plates 410 and 420 according to the present embodiment cover the front and rear surfaces of the battery cell stack 120, and the module frame 200 covers the upper, lower, and both side surfaces of the battery cell stack 120. Here, the front surface means the surface of the battery cell stack 120 in the x-axis direction, and the rear surface means the surface of the battery cell stack 120 in the -x-axis direction. The upper surface means the surface of the battery cell stack 120 in the z-axis direction, the lower surface means the surface of the battery cell stack 120 in the -z-axis direction, and both side surfaces mean the surfaces of the battery cell stack 120 in the y-axis and -y-axis directions, respectively. However, this is the surface referred to for convenience of explanation and may vary depending on the position of the object and the position of the observer. As described above, the front and rear surfaces of the battery cell stack 120 may be the surfaces where the protruding electrode leads 111 and 112 of the battery cells 110 are located.

[0056] According to the present embodiment, at least one of the module frame 200 or the end plates 410 and 420 can include a venting portion 700a for discharging gas and flame.

[0057] Hereinafter, with reference to FIGS. 8 to 11, a venting portion formed in the first end plate according to an embodiment of the present invention will be described in detail. To avoid repetition of the description, the description will be made with reference to the first end plate 410, but the same or similar structure can also be applied to the second end plate 420.

[0058] FIG. 8 is a perspective view showing an end plate and an insulating cover according to an embodiment of the present invention. FIG. 9 is a cross-sectional perspective view showing a state of being cut along the cutting line A-A' of FIG. 8. FIG. 10 is a cross-sectional view of the cut end plate and insulating cover of FIG. 9 viewed in the -y axis direction on the xz plane. FIG. 11 is a perspective view showing the end plate and insulating cover of FIG. 8 at different angles so that the surface facing the battery cell laminate can be seen.

[0059] Referring to FIGS. 8 to 11, the bending portion 700a according to the present embodiment is configured to guide the discharge paths of the gas and the flame to bend. That is, the bending portion 700a includes a passage connecting the inside of the battery module 100a wrapped by the module frame 200 and the end plates 410 and 420 to the outside, and the gas and the flame are discharged through the passage. However, the passage is not formed only by a straight line, but includes a bent portion so that the discharge paths of the gas and the flame are guided to bend.

[0060] Specifically, the bending portion 700a may include a through-hole 710a formed in the first end plate 410, a first cover portion 720a covering the through-hole 710a, and a first opening 730a formed on one side of the first cover portion 720a and communicating with the through-hole 710a. Here, the first cover portion 720a does not cover so as to completely seal one side of the through-hole 710a, but is spaced apart at a certain interval, and the first opening 730a can be formed only in the space where the first cover portion 720a is separated from one surface of the first end plate 410.

[0061] The through-hole 710a and the first opening 730a can be the passages through which the gas and the flame mentioned above are discharged.

[0062] The first cover part 720a can be in a form that covers the through-hole 710a on the outside. Also, the first cover part 720a can be connected to the first end plate 410 at a portion where the first opening 730a is not formed. In order to form such a structure, the area of the first cover part 720a may be larger than the opening area of the through-hole 710a.

[0063] Although four first openings 730a are shown as being formed in the y-axis direction, -y-axis direction, z-axis direction, and -z-axis direction with respect to one bending part 700a, there is no particular limitation on the number of the first openings 730a. Also, there is no limitation on the opening direction of the first opening 730a as long as it does not coincide with the opening direction of the through-hole 710a.

[0064] In the case of the conventional battery module 10, as described above, high-temperature heat, gas, flames, etc. are intensively discharged through the terminal bus bar opening 41H and the module connector opening 42H, which may damage the adjacent battery modules 10.

[0065] On the contrary, in the case of the battery module 100a according to the present embodiment, since a separate bending part 700a is provided, the discharge of gas and flames can be dispersed, and the gas and flames discharged through the terminal bus bar opening 410H and the module connector opening 420H can be greatly reduced.

[0066] Also, due to the first cover part 720a that covers the through-hole 710a, gas and flames do not pass through the through-hole 710a in a straight line. That is, as shown in FIG. 10, the bending part 700a including the first cover part 720a and the first opening 730a can guide the discharge paths of the gas and the flames to bend.

[0067] Specifically, the opening direction of the through-hole 710a and the opening direction of the first opening 730a may be different. More specifically, the opening direction of the through-hole 710a and the opening direction of the first opening 730a can be perpendicular to each other. As an example, as shown in FIG. 10, the opening direction of the through-hole 710a is a direction parallel to the x-axis, while the opening direction of the first opening 730a can be a direction parallel to the yz plane or a direction close to the yz plane. Therefore, the bending portion 700a can guide the discharge of the gas and the flame in a direction parallel to one surface of the first end plate 410.

[0068] In the case of high-temperature gas, there is no particular limitation on the discharge to the outside even if the discharge path is formed to be bent. On the contrary, in the case of a flame or a spark with strong straight-ahead properties, as in this embodiment, if the discharge path is designed to be bent, it is possible to limit the direct injection toward an adjacent battery module or the like. The bending portion 700a according to this embodiment can suppress the direct discharge of the flame. Even if the flame is discharged, the direction is regulated, and the damage received by other adjacent battery modules can be minimized. That is, it has the advantage that the gas discharge function does not deteriorate and the damage caused by the flame can be reduced.

[0069] There is no particular limitation on the number of such bending portions 700a, and they can be arranged singly or in plurality. As an example, FIGS. 8 to 11 show the case where three bending portions 700a are provided.

[0070] On the other hand, as described above, an insulating cover 800 for electrical insulation can be positioned between the first end plate 410 and the first bus bar frame (310, see FIG. 5). Any material that provides electrical insulation can be applied to the insulating cover 800 without limitation. At this time, as shown in FIG. 11, an insulating cover opening 800H can be formed at a position corresponding to the bending portion 700a in the insulating cover 800. The high-temperature gas and flame inside the battery module can pass through the insulating cover opening 800H and the bending portion 700a in sequence and be discharged to the outside.

[0071] Hereinafter, with reference to FIGS. 12 and 13, another embodiment of the present invention will be described in detail with respect to the bending portion formed in the module frame.

[0072] FIG. 12 is a perspective view showing a battery module according to another embodiment of the present invention. FIG. 13 is a cross-sectional view showing a cross-section cut along the cutting line B-B' of FIG. 12.

[0073] Referring to FIGS. 12 and 13, a battery module 100b according to another embodiment of the present invention includes a module frame 200 that houses a battery cell stack 120 and a bending portion 700b formed in the module frame 200. The bending portion 700b is configured to guide the discharge paths of the gas and the flame to bend. That is, the bending portion 700b includes a passage that connects the inside of the battery module 100b wrapped by the module frame 200 and the end plates 410 and 420 to the outside, and the gas and the flame are discharged through the passage. However, the passage is not configured to be only a straight line but includes a bent portion so that the discharge paths of the gas and the flame are guided to bend.

[0074] Such a bending portion 700b includes a through hole 710b formed in the module frame 200, a first cover portion 720b that covers the through hole 710b, and a first opening 730b formed on one side of the first cover portion 720b and communicating with the through hole 710b. Similar to the content described above, here, the first cover portion 720b does not cover one side of the through hole 710b so as to be completely sealed, but is spaced apart at a certain interval, and the first opening 730a can be formed only in the space where the first cover portion 720b is separated from one surface of the module frame 200.

[0075] The through hole 710b and the first opening 730b can be the passages through which the gas and the flame mentioned above are discharged.

[0076] The first cover portion 720b may be configured to cover the through-hole 710b on the outside. Also, the first cover portion 720b can be connected to the module frame 200 at a portion where the first opening 730b is not formed. In order to form such a structure, the area of the first cover portion 720b may be larger than the opening area of the through-hole 710b.

[0077] Similar to the bending portion 700a formed on the end plates 410, 420, the bending portion 700b according to the present embodiment includes the first cover portion 720b and the first opening 730b, and can guide the discharge paths of the gas and the flame to bend.

[0078] Specifically, the opening direction of the through-hole 710b and the opening direction of the first opening 730b may be different. More specifically, the opening direction of the through-hole 710b and the opening direction of the first opening 730b may be perpendicular to each other. As an example, as shown in FIG. 13, the opening direction of the through-hole 710b is a direction parallel to the z-axis, while the opening direction of the first opening 730b may be a direction parallel to the xy plane or a direction close to the xy plane. Therefore, the bending portion 700b can guide the discharge of the gas and the flame in a direction parallel to one surface of the module frame 200. The bending portion 700b according to the present embodiment has the advantage of not reducing the gas discharge function and being able to reduce the damage caused by the flame. Since the detailed content overlaps with the previously described content, it is omitted.

[0079] On the other hand, since the module frame 200 may have a relatively larger area compared to the end plates 410, 420, the number of the bending portions 700b can be increased compared to the case where they are formed on the end plates 410, 420. Also, the opening area of the first opening 730b can be increased. The increased number of the bending portions 700b and the opening area of the first opening 730b are effective due to the dispersion of the gas and the flame.

[0080] Also, since the bending portion 700b is formed on one surface of the module frame 200, the gas and the flame itself discharged in the direction where the end plate is located can be reduced.

[0081] In particular, as shown in the figure, a bending portion 700b is formed on the upper surface of the module frame 200. In this case, it is possible to guide the discharge of gas or flame to occur above the battery module 100b. Therefore, damage to other battery modules mainly arranged on the side surfaces can be reduced.

[0082] On the other hand, although the bending portion 700a formed on the end plates 410 and 420 and the bending portion 700b formed on the module frame 200 have been described separately, the battery module according to another embodiment of the present invention can include all of the bending portion 700a formed on the end plates 410 and 420 and the bending portion 700b formed on the module frame 200.

[0083] Hereinafter, with reference to FIGS. 14 to 17, a bending portion according to a modified embodiment of the present invention will be described in detail. In order to avoid repetition of the description, the description will be made based on the first end plate 410, but the same or similar structures can also be applied to the module frame 200 and the second end plate 420.

[0084] FIG. 14 is a perspective view showing an end plate and an insulating cover according to a modified embodiment of the present invention. FIG. 15 is a cross-sectional perspective view showing a state of being cut along the cutting line C-C' of FIG. 14. FIG. 16 is a cross-sectional view of the cut end plate and the insulating cover of FIG. 15 viewed in the -y-axis direction on the xz plane. FIG. 17 is a perspective view showing the end plate and the insulating cover of FIG. 14 at different angles so that the surface facing the battery cell laminate can be seen.

[0085] Referring to FIGS. 14 to 17, a bent portion 700c according to a modified embodiment of the present invention includes a through hole 710c formed in the first end plate 410, a first cover portion 720c covering the through hole 710c, and a first opening 730c formed on one side of the first cover portion 720c and communicating with the through hole 710c. Additionally, the bent portion 700c may further include a second cover portion 740c covering the through hole 710c while being located on the opposite side of the first cover portion 720c with respect to the through hole 710c, and a second opening 750c formed on one side of the second cover portion 740c and communicating with the through hole 710c. That is, the bent portion 700c according to the present embodiment may have a configuration in which the second cover portion 740c and the second opening 750c are further added to the bent portion 700a described above. The first cover portion 720c and the second cover portion 740c may be positioned at a certain interval from each other instead of completely covering one side and the other side of the through hole 710a, respectively. Only the first opening 730a may be formed in the space where the first cover portion 720c is separated from one surface of the first end plate 410, and only the second opening 750c may be formed in the space where the second cover portion 740c is separated from the other surface of the first end plate 410.

[0086] The first opening 730c, the through hole 710c, and the second opening 750c may be the passages through which the gas and flame mentioned above are discharged.

[0087] The second cover portion 740c and the first cover portion 720c may be positioned opposite to each other with the through hole 710c therebetween. More specifically, unlike the first cover portion 720c that covers the through hole 710c on the outside, the second cover portion 740c may be in a form that covers the through hole 710c on the inside. Also, the second cover portion 740c may be connected to the first end plate 410 in a portion where the second opening 750c is not formed. In order to form such a structure, the area of the second cover portion 740c may be larger than the opening area of the through hole 710c.

[0088] Although the case where four second openings 750c are formed in the y-axis direction, -y-axis direction, z-axis direction, and -z-axis direction with respect to one bending portion 700c is illustrated, there is no particular limitation on the number of second openings 750c. Also, there is no limitation on the opening direction of the second opening 750c as long as it does not coincide with the opening direction of the through hole 710c.

[0089] The first cover portion 720c and the second cover portion 740c that cover the through hole 710c prevent gas and flame from passing through the through hole 710c in a straight line. That is, the first cover portion 720c and the second cover portion 740c allow the discharge path of the gas and the flame to bend at least twice.

[0090] Specifically, the opening direction of the through hole 710c and the opening direction of the second opening 750c may be different. More specifically, the opening direction of the through hole 710c and the opening direction of the second opening 750c may be perpendicular to each other. As an example, as shown in FIG. 16, the opening direction of the through hole 710c is a direction parallel to the x-axis, while the opening direction of the second opening 750c may be a direction parallel to the yz plane or a direction close to the yz plane. That is, by arranging the second cover portion 740c in addition to the first cover portion 720c, the path for discharging the flame through the bending portion 700c can be set to be more complex. The more complex the flame discharge path becomes, the more effectively it can block a flame or spark with strong straight-line properties, and the flame intensity decreases as the instantaneously ejected flame passes through the second cover portion 740c and the first cover portion 720c in sequence. In other words, the bending portion 700c according to the present embodiment can have a greater flame extinguishing function.

[0091] Although terms indicating directions such as front, rear, left, right, up, and down are used in the present embodiment, such terms are for convenience of explanation and may vary depending on the position of the object to be described and the position of the observer.

[0092] One or more battery modules according to the above-described embodiment can be attached together with various control and protection systems such as a BMS (Battery Management System) and a cooling system to form a battery pack.

[0093] The battery module and the battery pack can be applied to various devices. Specifically, they can be applied to transportation means such as electric bicycles, electric vehicles, and hybrids, but are not limited thereto, and can be applied to various devices that can use secondary batteries.

[0094] As described above, the preferred embodiments of the present invention have been described in detail. However, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

Explanation of Reference Numerals

[0095] 100a, 100b Battery modules 120 Battery cell laminate 200 Module frame 410 First end plate 420 Second end plate 700a, 700b, 700c Venting parts

Claims

1. A battery cell stack in which a plurality of battery cells are stacked, A module frame for housing the battery cell stack, and An end plate covering the front and rear surfaces of the battery cell stack, At least one of the module frame or the end plate includes a venting portion for discharging gas and flame, The venting portion is in a form that guides the discharge paths of the gas and the flame to bend, The venting portion includes a through-hole formed in at least one of the module frame or the end plate, a first cover portion covering the through-hole, and a first opening formed on one side of the first cover portion and communicating with the through-hole, The venting portion further includes a second cover portion covering the through-hole while being located on the opposite side of the first cover portion with respect to the through-hole, and a second opening formed on one side of the second cover portion and communicating with the through-hole, a battery module.

2. The battery module according to claim 1, wherein the area of the first cover portion is larger than the opening area of the through-hole.

3. The battery module according to claim 1 or 2, wherein the opening direction of the through-hole and the opening direction of the first opening are different.

4. The battery module according to any one of claims 1 to 3, wherein the opening direction of the through-hole and the opening direction of the first opening are perpendicular to each other.

5. The battery module according to any one of claims 1 to 4, wherein the area of the second cover portion is larger than the opening area of the through-hole.

6. The battery module according to any one of claims 1 to 5, wherein the opening direction of the through-hole and the opening direction of the second opening are different.

7. The battery module according to any one of claims 1 to 6, wherein the opening direction of the through-hole and the opening direction of the second opening are perpendicular to each other.

8. The battery module according to any one of claims 1 to 7, wherein the exhaust paths of the gas and the flame are bent at least twice by the first cover portion and the second cover portion.

9. The battery module according to any one of claims 1 to 8, wherein the bending portion guides the exhaust of the gas and the flame in a direction parallel to at least one surface of the module frame or the end plate.

10. A battery cell stack in which a plurality of battery cells are stacked, A module frame for housing the battery cell stack, and An end plate covering the front and rear surfaces of the battery cell stack, At least one of the module frame or the end plate includes a bending portion for discharging gas and flame, The bending portion is in a form that guides the exhaust paths of the gas and the flame to bend, Further including an insulating cover located between the battery cell stack and the end plate, The bending portion is formed on the end plate, A battery module in which an insulating cover opening is formed at a position corresponding to the bending portion of the insulating cover.

11. A battery pack including the battery module according to any one of claims 1 to 10.

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