Battery module and battery pack including same

Abstract

A battery module according to an embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells are stacked; a module frame for accommodating the battery cell stack; and an exhaust frame disposed to cover one surface of the module frame, in which the exhaust frame includes a first exhaust layer disposed adjacent to the module frame and including a plurality of first exhaust passages, and a second exhaust layer disposed outside the first exhaust layer and including second exhaust passages.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0164567 filed in the Korean Intellectual Property Office on November 30, 2022, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module having enhanced safety and a battery pack including the same. Background Art

[0004] In modern society, as the use of portable devices such as mobile phones, laptops, video cameras, and digital cameras has become commonplace, technologies in the fields related to the above mobile devices have been actively developed. In addition, in order to solve the air pollution problem of existing gasoline vehicles using fossil fuels, rechargeable secondary batteries have been used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs), and the demand for the development of secondary batteries is also increasing.

[0005] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries and lithium secondary batteries. Among them, compared with nickel-based secondary batteries, lithium secondary batteries rarely have memory effects, so lithium secondary batteries have attracted much attention due to their advantages such as free charge and discharge, low self-discharge rate and high energy density.

[0006] These lithium secondary batteries mainly use lithium-based oxides and carbon materials as positive electrode active materials and negative electrode active materials, respectively. The lithium secondary battery includes an electrode assembly and a housing, in which a positive electrode plate and a negative electrode plate coated with positive electrode active materials and negative electrode active materials are provided, a separator is located between the positive electrode plate and the negative electrode plate, and the housing (i.e., the battery case) seals and stores the electrode assembly together with an electrolyte solution.

[0007] Generally, lithium secondary batteries may be classified into can type secondary batteries in which an electrode assembly is built in a metal can and pouch type secondary batteries in which an electrode assembly is built in a pouch of an aluminum laminate sheet, depending on the shape of a housing.

[0008] In the case of secondary batteries used in small devices, two to three battery cells are arranged, but in the case of secondary batteries used in medium and large devices such as automobiles, a battery module formed by electrically connecting a plurality of battery cells is used. In such a battery module, a plurality of battery cells are connected in series or in parallel to each other to form a battery cell stack, thereby increasing capacity and power. In addition, one or more battery modules can be installed together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0009] Meanwhile, battery modules including a plurality of battery cells may be gathered together and installed in medium and large equipment such as automobiles. The temperature of a battery module including a plurality of battery cells or a battery pack including these battery modules may rise rapidly and severely because the heat from the plurality of battery cells is accumulated in a small space. In other words, in the case of a battery module in which a plurality of battery cells are stacked and a battery pack equipped with these battery modules, high power can be obtained, but it is not easy to remove the heat generated by the battery cells during charging and discharging, and therefore, the possibility of explosion or fire increases. When an explosion or fire occurs, it is necessary to delay the spread of the ignition and the flame that occurs. Meanwhile, if the exhaust gas appearing in the battery cell is not discharged quickly at the beginning of thermal runaway, the gas will accumulate inside the module, further increasing the risk of fire and explosion, and therefore, the exhaust gas in the module needs to be discharged quickly to the outside. Therefore, there is a need for a method that can delay the flame from being transferred to adjacent modules while quickly discharging the internal exhaust gas when an event such as thermal runaway occurs in a battery module or a battery pack. Summary of the invention

[0010] Technical issues

[0011] The present disclosure attempts to provide a battery module and a battery pack including the same, which are capable of suppressing or delaying external discharge of flames or the like while quickly discharging exhaust gas generated at an early stage when an event such as thermal runaway occurs inside the battery module.

[0012] However, the problems to be solved by the exemplary embodiments of the present disclosure are not limited to the above-mentioned problems and can be expanded in various ways within the scope of the technical ideas included in the present disclosure.

[0013] Technical Solution

[0014] According to an exemplary embodiment, a battery module includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame that stores the battery cell stack; and an exhaust frame that is configured to cover a surface of the module frame, wherein the exhaust frame includes: a first exhaust layer and a second exhaust layer, the first exhaust layer being configured to be adjacent to the module frame and including a plurality of first exhaust channels, and the second exhaust layer being configured outside the first exhaust layer and including a second exhaust channel.

[0015] The plurality of first exhaust passages may be straight flow paths formed in a longitudinal direction of the battery module.

[0016] The second exhaust passage may be a meandering flow path formed in a zigzag shape throughout the second exhaust layer.

[0017] The module frame may include at least one exhaust hole formed on one surface contacting the first exhaust layer, and the exhaust hole is connected to at least one first inlet formed in the first exhaust layer.

[0018] The first exhaust layer includes at least one first partition wall separating the plurality of first exhaust channels from each other.

[0019] The at least one first partition wall may extend in the longitudinal direction of the battery module.

[0020] Each of the plurality of first exhaust passages may include a first inlet and a first outlet disposed on a side opposite to the first inlet.

[0021] The second exhaust layer may include at least one second inlet formed on one surface contacting the first exhaust layer, and the at least one second inlet is each connected to the first outlet.

[0022] The second exhaust passage may include a second outlet formed on the other surface on an opposite side of the first exhaust layer and located on an opposite side of the second inlet in the longitudinal direction of the battery module.

[0023] The second exhaust layer may include a plurality of second partition walls constituting the second exhaust channel.

[0024] The second partition wall may be disposed to extend in a direction different from that of the first partition wall.

[0025] The second exhaust passage has a length longer than that of each of the first exhaust passages.

[0026] According to another exemplary embodiment, a battery pack includes one or more of the above-described battery modules.

[0027] Beneficial Effects

[0028] According to an exemplary embodiment of the present disclosure, a battery module having improved safety by quickly discharging exhaust gas generated during a fire inside a battery module and suppressing or delaying the spread of flames may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a diagram illustrating a battery module according to an exemplary embodiment of the present disclosure.

[0030] Figure 2 yes Figure 1 An exploded perspective view of a battery module.

[0031] Figure 3 is along Figure 2 A cross-sectional view of the exhaust frame taken along line AA'.

[0032] Figure 4 yes Figure 3 A top view of the first exhaust layer of the exhaust frame.

[0033] Figure 5 yes Figure 3 A top view of the second exhaust layer of the exhaust frame. DETAILED DESCRIPTION

[0034] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to allow those skilled in the art to practice the present disclosure. The present disclosure can be implemented in various forms and is not limited to the examples described herein.

[0035] In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present disclosure, and the same reference numerals denote the same elements throughout the specification.

[0036] For the sake of convenience of explanation, the size and thickness of each component shown in the drawings may be arbitrarily shown, and therefore, the present disclosure is not necessarily limited to the exemplary embodiments shown in the drawings. In the drawings, the thickness of layers, films, panels, regions, etc. are exaggerated for the sake of clarity. In addition, in the drawings, the thickness of some layers and regions may be exaggerated for the sake of convenience of explanation.

[0037] It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, the element can be directly on the other element, or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, no intervening elements are present. In addition, when an element is "above" or "on" a reference portion, this may mean that the element is located above or below the reference portion, and does not necessarily mean that the element is "above" or "on" in the opposite direction of gravity.

[0038] In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0039] Hereinafter, a battery module according to an exemplary embodiment of the present disclosure will be described with reference to the accompanying drawings.

[0040] Figure 1 is a diagram showing a battery module according to an exemplary embodiment of the present disclosure, Figure 2 yes Figure 1 An exploded perspective view of a battery module.

[0041] Reference Figure 1 and Figure 2 , a battery module 100 according to an exemplary embodiment of the present disclosure includes: a battery cell stack 110 including one or more battery cells; a module frame 400 storing the battery cell stack 110 ; and an exhaust frame 200 disposed to cover one surface of the module frame 400 .

[0042] The module frame 400 has an open front surface and a rear surface, and may include an end plate 300 covering the front surface and the rear surface. Figure 2 In the embodiment, both ends in the X-axis direction are open, and the end plates 300 cover the ends. Figure 2 , the module frame 400 is shown as having an integrated square tube shape, but is not limited thereto, and the module frame 40 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.

[0043] In addition, a bus bar frame 500 accommodated in the module frame 400 may be provided together with the battery cell stack 110. The bus bar frame 500 includes an upper frame 510 located at the top of the battery cell stack 110, a front frame 520 located at the front of the battery cell stack 110, and a rear frame 530 located at the rear of the battery cell stack 110, and bus bars 540 connected to electrode leads of battery cells constituting the battery cell stack 110 may be mounted on the front frame 520 and the rear frame 530.

[0044] Meanwhile, although not shown, a thermally conductive resin layer (not shown) formed by injecting a thermally conductive resin may be provided between the lower surface of the battery cell stack 110 and the module frame 400. In addition, a heat sink 800 may be provided on a side surface of the battery cell stack 110 and may be accommodated in the module frame 400 together.

[0045] The exhaust frame 200 may be disposed on one surface of the module frame 400 (eg, disposed on the lower surface of the module frame 400 in the present exemplary embodiment). Figures 3 to 5 The configuration of the exhaust frame 200 is described in more detail.

[0046] Figure 3 is along Figure 2 A cross-sectional view of the exhaust frame taken along line A-A', Figure 4 yes Figure 3 a top view of a first exhaust layer of an exhaust frame, and Figure 5 yes Figure 3 A top view of the second exhaust layer of the exhaust frame.

[0047] The exhaust frame 200 may be disposed on one surface of the module frame 400 (e.g., disposed on the lower surface of the module frame 400 as in the present exemplary embodiment). The exhaust frame 200 may have a dual structure including a first exhaust layer 210 disposed adjacent to the module frame 400 and a second exhaust layer 220 disposed adjacent to the first exhaust layer 210 and outside the first exhaust layer 210. In addition, the exhaust frame 200 may have a plate shape to cover one surface of the module frame 400, and may be formed of a plurality of plates to have a dual structure. Here, the plate forming the exhaust frame 200 may be formed of a heat-resistant material such as metal, and may be connected to the module frame 400 by a method such as welding, but is not limited thereto, and various methods may be used. The exhaust frame 200 includes an inlet and an outlet and a plurality of channels therebetween, and exhaust gas discharged from the inside of the module frame 400 may flow in and be discharged to the outside through the inlet and the outlet.

[0048] That is, at least one exhaust hole 410 is formed on one surface of the module frame 400 facing the exhaust frame 200, through which exhaust gas or flame can be exhausted when thermal runaway occurs. In addition, at least one first inlet 211 is formed on one surface of the first exhaust layer 210 facing the module frame 400, communicating with each exhaust hole 410. Exhaust gas flowing into the first inlet 211 passes through the first exhaust layer 210 and the second exhaust layer 220 and is exhausted to the outside.

[0049] At this time, the plurality of first exhaust channels 214 formed in the first exhaust layer 210 are formed as straight flow paths formed in the longitudinal direction of the battery module 100 (ie, in the X direction in the figure). In addition, the plurality of first exhaust channels 214 are formed to be separated or isolated by at least one first partition wall 213. That is, the first inlet 211 communicating with the exhaust hole 410 is formed at one end of each first exhaust channel 214 separated by the first partition wall 213, and the first outlet 212 for discharging the exhaust gas is formed on the opposite side (ie, formed at the other end located on the opposite side in the X-axis direction). Therefore, the exhaust gas flowing into each first inlet 211 can be discharged through the first outlet 212 via the first exhaust channel 214, and will not diffuse or reverse even in the first exhaust layer 210. At this time, the first partition wall 213 can be formed of the same material as the plate forming the exhaust frame 200, or can be formed of a material having equivalent heat resistance.

[0050] In this way, by forming the first exhaust passage 214 included in the first exhaust layer 210 into a straight flow path, the exhaust gas can be quickly discharged to the second exhaust layer 220 without flow resistance. That is, by quickly discharging the exhaust gas or flame initially generated to the next passage, i.e., the second exhaust layer 220, the risk of explosion that increases as the exhaust gas or flame accumulates within the module frame 400 can be prevented.

[0051] At least one second inlet 221 communicating with the first outlet 212 is formed on one surface of the second exhaust layer 220 facing the first exhaust layer 210. In this exemplary embodiment, Figure 3 As shown, the first outlet 212 and the second inlet 221 are shown to be formed in the same configuration on one plate. However, not limited thereto, each exhaust layer may also be formed to include a separate plate.

[0052] The exhaust gas flowing in from the first exhaust layer 210 through the second inlet 221 is along Figure 5 The path indicated by the arrow in the middle moves through the second exhaust passage 224. At this time, Figure 5 As shown, the second exhaust passage 224 may be formed as a zigzag or meandering flow path across the second exhaust layer 220. For example, Figure 5As shown, the second partition wall 223 parallel to the width direction of the battery module 100 (the Y direction in the figure) is arranged to alternately contact the two side walls, thereby obtaining a second exhaust channel 224 having a tortuous path. However, without limitation thereto, a path that can increase the movement path of the exhaust gas within the second exhaust layer 220 can be appropriately adopted, especially a structure in which the second exhaust channel 224 is longer than the first exhaust channel 214 of the first exhaust layer 210. In this way, by increasing the resistance of the exhaust gas along the path along which it moves, the discharge of the exhaust gas to the outside can be suppressed or delayed as much as possible. At this time, the second partition wall 223 can be formed of the same material as the plate forming the exhaust frame 200, or can be formed of a material having equivalent heat resistance. In addition, in Figure 3 In the cross-sectional view of FIG. 2 , the arrow indicating the path of the exhaust gas in the second exhaust layer 220 appears to be blocked by the second partition wall 223, but this is only a cross-sectional view. Figure 5 As shown, the exhaust gas may move in a zigzag shape along the serpentine flow path even if it is blocked by the partition wall.

[0053] In the second exhaust layer, the second outlet 222 is formed on the opposite side of the portion where the second inlet 221 is formed (i.e., formed at the opposite end of the battery module 100 in the longitudinal direction (X-axis direction)). The exhaust gas moving along the second exhaust channel 224 can be discharged to the outside through the second outlet 222. In this way, by forming the second exhaust channel 224 as a zigzag meandering flow path in the second exhaust layer 220, the exhaust gas can be delayed as much as possible to be discharged to the outside and the flame can be suppressed from being discharged to the outside, thereby suppressing the transfer of the flame.

[0054] According to an exemplary embodiment of the present disclosure, when an event such as thermal runaway occurs in the battery cell stack 110 within the module frame 400, the exhaust gas generated in the initial stage can be quickly discharged to the outside of the module frame 400 through the first exhaust channel 214, thereby eliminating the risk of explosion due to the accumulation of exhaust gas. At the same time, by further providing a second exhaust channel 224 that is connected to the first exhaust channel 214 and has a high resistance flow path shape, the discharge of the flame generated from the module frame 400 to the outside can be delayed as much as possible, thereby improving safety by suppressing the flame from being transmitted to adjacent modules.

[0055] One or more battery modules according to the present exemplary embodiment described above may be mounted together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0056] The battery module or battery pack can be applied to various devices. These devices can be applied to transportation units such as electric bicycles, electric vehicles, and hybrid vehicles, but are not limited thereto, and can be applied to various devices that can use secondary batteries.

[0057] The embodiments of the present disclosure have been described in detail, but the scope of the present disclosure is not limited thereto, and various variations and modifications made by those skilled in the art using the basic concepts of the present disclosure defined in the claims also belong to the scope of the present disclosure.

[0058] [Description of Reference Signs]

[0059] 100: Battery module

[0060] 110: Battery cell stack

[0061] 200: Exhaust frame

[0062] 210: First exhaust layer

[0063] 214: First exhaust channel

[0064] 220: Second exhaust layer

[0065] 224: Second exhaust channel

[0066] 300: End plate

[0067] 400: Module Framework

[0068] 410: Exhaust hole

[0069] 500: Busbar frame

Claims

1. A battery module, comprising: A battery cell stack, in which a plurality of battery cells are stacked; a module frame storing the battery cell stack; as well as an exhaust frame, the exhaust frame being arranged to cover a surface of the module frame, Wherein, the exhaust frame comprises: A first exhaust layer is disposed adjacent to the module frame and includes a plurality of first exhaust channels, and a second exhaust layer is disposed outside the first exhaust layer and includes a second exhaust channel.

2. The battery module according to claim 1, wherein: The plurality of first exhaust passages are straight flow paths formed in a longitudinal direction of the battery module.

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

4. The battery module according to claim 3, wherein: The module frame includes at least one exhaust hole formed on one surface contacting the first exhaust layer, and The exhaust hole is connected to at least one first inlet formed in the first exhaust layer.

5. The battery module according to claim 4, wherein: The first exhaust layer includes at least one first partition wall separating the plurality of first exhaust channels from each other.

6. The battery module according to claim 5, wherein: The at least one first partition wall extends in the longitudinal direction of the battery module.

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

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

9. The battery module according to claim 8, wherein: The second exhaust passage includes a second outlet formed on the other surface located on an opposite side of the first exhaust layer and located on an opposite side of the second inlet in the longitudinal direction of the battery module.

10. The battery module according to claim 5, wherein: The second exhaust layer includes a plurality of second partition walls constituting the second exhaust channel.

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

12. The battery module according to claim 1, wherein: The second exhaust passage has a length longer than that of each of the first exhaust passages. 13 . A battery pack comprising one or more battery modules according to claim 1 .

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