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 a venting frame disposed to cover one surface of the module frame. The venting frame includes a first venting layer disposed adjacent to the module frame and including a plurality of first venting passages, and a second venting layer disposed outside the first venting layer and including second venting passages.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0164567, filed on November 30, 2022, and all contents disclosed in the literature of the Korean patent application are included as part of this specification.

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

Background Art

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

[0004] Current commercially available secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, nickel - zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries have attracted attention for their advantages such as almost no memory effect compared to nickel - based secondary batteries, free charge and discharge, very low self - discharge rate, and high energy density.

[0005] Such lithium secondary batteries mainly use lithium - based oxides and carbon materials 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 therebetween, and an exterior material that hermetically stores the electrode assembly together with an electrolytic solution, that is, a battery case.

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

[0007] In the case of secondary batteries used in small devices, two or three battery cells are arranged. In the case of secondary batteries used in medium- to large-sized devices such as automobiles, a battery module in which a large number of battery cells are electrically connected is used. In such a battery module, a large number of battery cells are connected in series or in parallel with each other to form a battery cell stack, thereby improving the capacity and output. In addition, one or more battery modules can be mounted together with various control and protection systems such as a BMS (Battery Management System) and a cooling system to form a battery pack.

[0008] On one hand, battery modules containing a number of battery cells can be assembled and mounted on medium to large-sized devices such as automobiles. In battery modules equipped with a number of battery cells or battery packs assembled with such battery modules, the heat generated from the number of battery cells is aggregated in a narrow space, and the temperature may rise rapidly and drastically. That is, in the case of a battery module in which a number of battery cells are stacked and a battery pack equipped with such a battery module, high output can be obtained, but it is not easy to remove the heat generated from the battery cells during charging and discharging, and for this reason, the possibility of explosion and ignition also increases. When such an explosion and ignition occur, it is necessary to delay the ignition and the transition of the generated flame. At the same time, if the venting gas generated from the battery cells at the initial stage of thermal runaway is not discharged quickly, the gas accumulates inside the module and the risk of ignition and explosion becomes even greater. Therefore, the venting gas inside the module needs to be discharged quickly to the outside. Therefore, when an event such as thermal runaway occurs in a battery module or a battery pack, a solution is required that can delay the flame transition to surrounding modules while quickly discharging the internal venting gas.

Summary of the Invention

Problems to be Solved by the Invention

[0009] Embodiments of the present invention are proposed to solve such problems. When an event such as thermal runaway occurs inside a battery module, the venting gas generated initially is quickly discharged, and at the same time, external discharge such as flames can be suppressed or delayed. The purpose is to provide a battery module and a battery pack including the same.

[0010] However, the problems to be solved by the embodiments of the present invention are not limited to the above-mentioned problems, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0011] 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 a venting frame arranged to cover one surface of the module frame. The venting frame includes a first venting layer arranged adjacent to the module frame and including a plurality of first venting passages, and a second venting layer arranged outside the first venting layer and including a second venting passage.

[0012] The plurality of first venting passages may be linear flow paths formed along the length direction of the battery module.

[0013] The second venting passage may be a meandering flow path formed in a zigzag shape over the entire second venting layer.

[0014] The module frame includes at least one vent hole formed on one surface in contact with the first venting layer, and the vent hole can be connected to at least one first inlet formed in the first venting layer.

[0015] The first venting layer may include at least one first partition wall that separates the plurality of first venting passages from each other.

[0016] The first partition wall can extend along the length direction of the battery module.

[0017] Each of the first venting passages may include a first inlet and a first outlet arranged on the opposite side of the first inlet.

[0018] The second venting layer includes at least one second inlet formed on one surface in contact with the first venting layer, and the second inlet can be connected to the first outlet respectively.

[0019] The second venting passage is formed on the other surface located on the opposite side of the first venting layer, and may include a second discharge port located on the opposite side of the battery module in the length direction from the second inlet port.

[0020] The second venting layer may include a plurality of second partition walls constituting the second venting passage.

[0021] The second partition wall can be arranged to extend in a direction different from that of the first partition wall.

[0022] The length of the second venting passage can also be longer than the respective lengths of the first venting passages.

[0023] A battery pack according to another embodiment of the present invention can include at least one or more of the above-described battery modules.

Advantages of the Invention

[0024] According to an embodiment of the present invention, venting gas generated during ignition inside the battery module can be quickly discharged, and the propagation of the flame can be suppressed or delayed, thereby providing a battery module with improved safety.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0026] Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those skilled in the art to which the present invention pertains can easily implement them. The present invention can be implemented in several different forms and is not limited to the embodiments described herein.

[0027] To clearly explain the present invention, parts not related to the explanation are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

[0028] In addition, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to those shown in the drawings. In the drawings, the thickness is enlarged to clearly represent a plurality of layers and regions. And, in the drawings, for convenience of explanation, the thicknesses of some layers and regions are exaggerated.

[0029] In addition, when a part such as a layer, a film, a region, or a plate is "on" or "above" another part, this includes not only the case where it is "directly above" another part but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in the middle. Also, being "on" or "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" or "upward" in the direction opposite to gravity.

[0030] Also, throughout the specification, when a part "includes" a certain component, it means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0031] Hereinafter, with reference to the drawings, a battery module according to an embodiment of the present invention will be described.

[0032] FIG. 1 is a drawing showing a battery module according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the battery module of FIG. 1.

[0033] Referring to FIGS. 1 and 2, a battery module 100 according to an embodiment of the present invention includes a battery cell laminate 110 including one or more battery cells, a module frame 400 for housing the battery cell laminate 110, and a venting frame 200 arranged to cover one surface of the module frame 400.

[0034] The module frame 400 has a form in which the front and rear surfaces are open, and may be provided with an end plate 300 that covers the front and rear surfaces. That is, in FIG. 2, both ends in the X-axis direction are open, and the end plate 300 is formed to cover the ends. In FIG. 2, the module frame 400 is shown as having an integral shape with a square tubular shape, but is not limited thereto, and may have a shape in which an upper plate is coupled to a U-shaped frame having a lower surface and side walls, or a shape in which a lower plate is coupled to an inverted U-shaped frame having an upper surface and side walls.

[0035] Further, a bus bar frame 500 housed in the module frame 400 together with the battery cell laminate 110 can be provided. The bus bar frame 500 can include an upper frame 510 located above the battery cell laminate 110, a front frame 520 located in front of the battery cell laminate 110, and a rear frame 530 located behind the battery cell laminate 110, and a bus bar 540 connected to the electrode leads of the battery cells constituting the battery cell laminate 110 can be mounted on the front frame 520 and the rear frame 530.

[0036] On the other hand, although not shown, a thermally conductive resin layer (not shown) formed by injecting a thermally conductive resin can be arranged between the lower surface of the battery cell laminate 110 and the module frame 400. Further, a heat sink 800 is provided on the side surface of the battery cell laminate 110 and can be housed together in the module frame 400.

[0037] On one side of the module frame 400, in this embodiment, the bending frame 200 can be arranged on the lower surface of the module frame 400. Hereinafter, with further reference to FIGS. 3 to 5, the configuration of the bending frame 200 will be described in more detail.

[0038] FIG. 3 is a drawing showing a cross section of the bending frame along A-A' of FIG. 2, FIG. 4 is a drawing of the first bending layer of the bending frame in FIG. 3 viewed from above, and FIG. 5 is a drawing of the second bending layer of the bending frame in FIG. 3 viewed from above.

[0039] The bending frame 200 can be arranged on one side of the module frame 400, for example, on the lower surface of the module frame 400 as in this embodiment. The bending frame 200 can have a double structure including a first bending layer 210 arranged adjacent to the module frame 400 and a second bending layer 220 arranged outside the first bending layer 210 adjacent to the first bending layer 210. Also, it can have a plate shape so as to cover one side of the module frame 400, and can be formed to have a double structure by a plurality of plates. At this time, the plates forming the bending frame 200 can be formed of a heat-resistant material such as metal and can be coupled to the module frame 400 by a method such as welding, but is not limited thereto, and can be applied in various ways. Such a bending frame is configured to include an inlet and an outlet through which the bending gas discharged from the inside of the module frame 400 flows in and is discharged to the outside, and a plurality of passages therebetween.

[0040] That is, at least one vent hole 410 through which bending gas or flames can be discharged is formed on one surface of the module frame 400 facing the bending frame 200 when thermal runaway occurs. And at least one first inlet 211 communicating with each of the vent holes 410 is formed on one surface of the first bending layer 210 facing the one surface of the module frame 400. The bending gas flowing into the first inlet 211 is discharged to the outside through the first bending layer 210 and the second bending layer 220.

[0041] At this time, the plurality of first bending passages 214 formed in the first bending layer 210 are formed in a linear flow path linearly formed along the length direction of the battery module 100, that is, the x direction in the drawing. Also, the plurality of first bending passages 214 are formed so as to be separated or isolated by at least one first partition 213. That is, at one end of each of the first bending passages 214 separated by the first partition 213, a first inlet 211 communicating with the vent hole 410 is respectively formed, and at the other end located on the opposite side, that is, the opposite side in the x-axis direction, a first outlet 212 through which the bending gas is discharged is respectively formed. Thereby, the bending gas flowing into each of the first inlets 211 can be discharged through the first outlet 212 through the first bending passage 214 into which it has flowed without diffusing or reversing in the first bending layer 210. At this time, the first partition 213 can be formed of the same material as the plate constituting the bending frame 200 or a material having equivalent heat resistance.

[0042] By forming the first bending passages 214 included in the first bending layer 210 in a linear flow path in this way, the bending gas can be quickly discharged to the second bending layer 220 without flow path resistance. That is, by quickly discharging the initially generated bending gas or flames to the next passage, that is, the second bending layer 220, it is possible to prevent accumulation inside the module frame 400 and an increase in the explosion risk.

[0043] On one side of the second bending layer 220 facing the first bending layer 210, at least one second inlet 221 communicating with the first outlet 212 is formed. In this embodiment, as shown in FIG. 3, the first outlet 212 and the second inlet 221 are shown as being formed in the same configuration on one plate, but the present invention is not limited thereto, and each bending layer may be formed to include a separate plate.

[0044] The bending gas flowing in from the first bending layer 210 through the second inlet 221 moves along a path as indicated by the arrow in FIG. 5 through the second bending passage 224. At this time, as shown in FIG. 5, the second bending passage 224 can be formed as a meandering flow path having a zigzag shape or a winding shape across the second bending layer 220. For example, as shown in FIG. 5, by arranging the second partition wall 223 parallel to the width direction (y direction in the drawing) of the battery module 100 so as to alternately contact both side walls, a second bending passage 224 having a winding path can be obtained. However, the present invention is not limited thereto, and any configuration that can lengthen the movement path of the bending gas within the second bending layer 220, particularly a configuration in which the second bending passage 224 has a longer length than the first bending passage 214 of the first bending layer 210, can be appropriately adopted. By increasing the resistance of the path along which the bending gas moves in this way, it is possible to suppress or maximize the delay of the bending gas being discharged to the outside. At this time, the second partition wall 223 can be formed of the same material as the plate constituting the bending frame 200 or a material having equivalent heat resistance. Also, in the cross-sectional view of FIG. 3, the arrow indicating the path of the bending gas in the second bending layer 220 appears to be blocked by the second partition wall 223, but this is only an illustration in the cross-section, and as shown in FIG. 5, even if blocked by the partition wall, the bending gas can move in a zigzag manner along the meandering flow path.

[0045] On the opposite side of the portion where the second inlet 221 is formed in the second bending layer 220, that is, at the end opposite to the length direction (x-axis direction) of the battery module 100, a second outlet 222 is formed. The bending gas that has moved along the second bending passage 224 can be disposed outside through the second outlet 222. In this way, in the second bending layer 220, by forming the second bending passage 224 into a meandering flow path formed in a zigzag shape, the discharge of the bending gas to the outside can be maximally delayed. Therefore, it is possible to suppress the release of flames or the like to the outside and suppress the transition of the flames.

[0046] Thus, according to an embodiment of the present invention, when an event such as thermal runaway occurs in the battery cell stack 110 inside the module frame 400, the initially generated bending gas is quickly discharged to the outside of the module frame 400 through the linear first bending passage 214 included in the first bending layer 210, thereby removing the risk of explosion due to the accumulation of the bending gas. At the same time, by further providing the second bending passage 224 that communicates with the first bending passage 214 and has a high-resistance flow path form, it is possible to maximally delay or suppress the discharge of flames or the like generated from the module frame 400 to the outside. Therefore, the safety can be improved by suppressing the transition of the flames to the adjacent modules.

[0047] One or more of the battery modules according to the above-described embodiment can be mounted together with various control and protection systems such as a BMS (Battery Management System) and a cooling system to form a battery pack.

[0048] The battery module and the battery pack can be applied to various devices. Such devices can be applied to transportation means such as electric bicycles, electric vehicles, and hybrid cars, but are not limited thereto, and can be applied to various devices that can use secondary batteries.

[0049] As described above in detail for the preferred embodiments of the present invention, 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 fall within the scope of the rights of the present invention.

Description of Reference Numerals

[0050] 100: Battery module 110: Battery cell stack 200: Bending frame 210: First bending layer 214: First bending passage 220: Second bending layer 224: Second bending passage 300: End plate 400: Module frame 410: Vent hole 500: Bus bar frame

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 A venting frame disposed so as to cover one surface of the module frame, wherein the venting frame includes a first venting layer disposed adjacent to the module frame and including a plurality of first venting passages, and a second venting layer disposed outside the first venting layer and including a second venting passage, the battery module.

2. The battery module according to claim 1, wherein the plurality of first venting passages are linear flow paths formed along the length direction of the battery module.

3. The battery module according to claim 2, wherein the second venting passage is a meandering flow path formed in a zigzag shape over the entire second venting layer.

4. The module frame includes at least one vent hole formed on one surface in contact with the first venting layer, and the vent hole is connected to at least one first inlet formed in the first venting layer, the battery module according to claim 3.

5. The first venting layer includes at least one first partition wall for separating the plurality of first venting passages from each other, the battery module according to claim 4.

6. The battery module according to claim 5, wherein the first partition wall extends along the length direction of the battery module.

7. The battery module according to claim 5, wherein each of the plurality of first venting passages includes the first inlet and a first outlet disposed on the opposite side of the first inlet.

8. The second venting layer includes at least one second inlet formed on one surface in contact with the first venting layer, and the second inlet is respectively connected to the first outlet, the battery module according to claim 7.

9. The second venting passage is formed on the other surface located on the opposite side of the first venting layer, and includes a second outlet located on the opposite side of the length direction of the battery module from the second inlet, the battery module according to claim 8.

10. The second venting layer includes a plurality of second partition walls constituting the second venting passage, the battery module according to claim 5.

11. The battery module according to claim 10, wherein the second partition wall extends in a direction different from that of the first partition wall.

12. The battery module according to claim 1, wherein the length of the second bending passage is longer than the respective lengths of the first bending passages.

13. A battery pack including one or more of the battery modules according to claim 1.

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