Thermal propagation prevention battery module

Abstract

The present invention provides a structure of a battery module including: a cell stack in which a plurality of battery cells and a barrier member interposed between the battery cells are stacked in the width direction of the battery module; a housing including a module frame for accommodating the cell stack and a cover for covering the module frame in a first direction; and a barrier accommodation part, which is provided to be connected to the inner surface of the cover and has a shape open in a second direction opposite to the first direction and into which an end toward the first direction of the barrier member is inserted, wherein the barrier member and the barrier accommodation part have overlapping sections overlapping in the width direction over a predetermined length parallel to the first direction, and the barrier member and the barrier accommodation part are slidable in a direction parallel to the first direction in a state where the contact with each other is maintained.

Description

Thermally conductive battery module

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2023-0149919, dated November 2, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a structure of a battery module including a cell stack in which a plurality of pouch-shaped cells are stacked, in which thermal runaway of a module unit due to heat transmission between cells is prevented.

[0003] Secondary batteries, which boast high electrical properties such as high energy density and easy applicability across a wide range of product groups, are widely used not only in portable devices but also in electric or hybrid vehicles powered by electrical power sources, as well as in power storage devices. These batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0004] While small mobile devices typically use one or two or three battery cells per device, medium- to large-sized devices, such as automobiles, require high output and large capacity. Therefore, medium- to large-sized battery modules, which electrically connect multiple battery cells, are used.

[0005] Since it is desirable to manufacture medium- to large-sized battery modules with as small a size and weight as possible, square batteries and pouch-type batteries that can be stacked with high integration and have a small weight per capacity are mainly used as battery cells for medium- to large-sized battery modules.

[0006] Figure 1 illustrates the structure of a pouch-type battery cell. Referring to this, a typical pouch-type battery cell (11) has a configuration in which an electrode assembly (110) is accommodated in a pouch (111). The pouch (111) accommodates the electrode assembly (110) and can be folded in half, and fusion-sealed at a sealing portion (111S) provided on one side in the height direction. In order to have a high voltage and / or a high capacity, a plurality of battery cells (11) can be stacked to form a cell stack.

[0007] Fig. 2 illustrates the configuration of a cell stack. Referring to this, a plurality of battery cells (11) may be stacked in the width direction to form a cell stack (1). The cell stack (1) may also include a barrier member (12) interposed between the battery cells (11) to prevent heat transmission between the battery cells (11). At this time, the battery cells (11) may form one or more cell banks (10) isolated by the barrier member (12). Such cell stacks (1) may be electrically connected to form one module.

[0008] Figures 3 and 4 illustrate the structure of a typical battery module. Referring to these, the battery module (M) may include a busbar frame assembly (2) connected to the front of the cell stack (1) to electrically connect the battery cells (11) to each other, and a housing (3) that accommodates the cell stack (1).

[0009] Meanwhile, the battery cell (11) may experience thermal runaway due to a short circuit or impact. The high-temperature gas and flame generated at this time may be discharged upward from the battery cell (11) as the fusion portion of the sealing portion (111S) melts. The gas and flame may transmit heat to other battery cells through the free space within the housing above the cell stack. Accordingly, there is a risk that not only the battery cell (11) but also other battery cells may ignite in a chain reaction, resulting in thermal runaway at the module level.

[0010] The present invention was created under the background of the above-described prior art, and its purpose is to provide a structure of a battery module in which heat transmission between battery cells is delayed or prevented.

[0011] Specifically, the present invention aims to provide a structure of a battery module in which thermal runaway of a module unit is delayed or prevented by blocking heat transmission between cells due to high-temperature gases and flames discharged from the battery cells.

[0012] The present invention also seeks to provide a structure of a battery module in which the heat transfer prevention structure and the insulation structure can be maintained despite deformation due to thermal runaway.

[0013] Another technical challenge of the present invention is to provide a structure of a battery module that is resistant to structural deformation due to assembly tolerance or swelling, and is easy to manufacture.

[0014] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0015] In order to solve the above problem, the present invention provides a battery module structure including: a cell stack in which a plurality of battery cells and a barrier member interposed between the battery cells are stacked in the width direction; a housing including a module frame that accommodates the cell stack and a cover that covers a first direction of the module frame; and a barrier receiving portion connected to an inner surface of the cover and having a shape that is open in a second direction opposite to the first direction, into which an end of the barrier member in the first direction is inserted; wherein the barrier member and the barrier receiving portion have an overlapping section that overlaps in the width direction over a predetermined length parallel to the first direction, and the barrier member and the barrier receiving portion are slidable in a direction parallel to the first direction while maintaining contact with each other.

[0016] The battery cell may be a pouch-shaped battery cell including an electrode assembly and a pouch that accommodates the electrode assembly and is folded in half and sealed at a sealing portion at one end thereof. The sealing may be a fusion sealing, and thus the sealing portion may be melted by high heat and serve as a passage through which gas and flame generated within the pouch are primarily discharged in a first direction. However, the structure of the battery cell is not limited to a pouch-shaped one.

[0017] The above barrier member may include a heat-resistant material. Accordingly, even in a thermal runaway situation, the barrier member can maintain its structure and block heat transmission between cells.

[0018] The barrier member may protrude in a first direction relative to the cell stack. The protruding barrier member may partition at least a portion of the separation space between the cell stack and the cover in the width direction to prevent heat transmission between cells due to gas and flames propagating through the separation space.

[0019] At this time, the barrier member and the barrier receiving portion can slide in a direction parallel to the first direction while maintaining contact with each other, so that the separation space can be maintained as being divided in the width direction even if the separation distance between the cover and the cell stack changes due to deformation of the cover.

[0020] The barrier member and / or the barrier receiving portion may comprise a compressible material. Preferably, the barrier member and / or the barrier receiving portion may be compressed in the width direction as the barrier member is inserted into the barrier receiving portion. Accordingly, the barrier member and the barrier receiving portion may exchange width-wise elastic restoring forces with each other, thereby achieving closer contact and sealing.

[0021] Additionally, when the barrier member includes a compressible material, the barrier member can absorb the assembly tolerance of the cell stack and the swelling of the battery cell.

[0022] The barrier member and / or the barrier receiving portion may include a compressible pad including a compressible material and a pair of rigid plates laminated on both sides of the compressible pad in the width direction. The rigid plates preferably include a heat-resistant material. Due to the multilayer structure of the barrier member and / or the barrier receiving portion, heat resistance, structural stability, insulation, and / or assembling properties of the barrier member and / or the barrier receiving portion can be simultaneously secured.

[0023] The barrier receiving portion may include a pair of side wall portions that protrude from the inner surface of the cover on both sides in the width direction of the barrier member and extend in the length direction. When the barrier receiving portion includes a compressible material, the compressible material is preferably included in at least the side wall portions.

[0024] The barrier receiving portion may include a connecting portion provided on the inner surface of the cover, and having one end of each of the pair of side wall portions connected to each of the widthwise ends thereof. The connecting portion may be formed of a flexible body that deforms together with the cover as it deforms. That the connecting portion is formed of a flexible body may mean that the bending rigidity of the connecting portion is not greater than the bending rigidity of the cover, and thus the connecting portion connected to the cover cannot resist the deformation of the cover. As the connecting portion deforms together with the cover, the inner width of the side wall portion may narrow, so that it may come into close contact with the barrier member.

[0025] At the first direction side end of the above barrier member, a tapered portion whose width becomes narrower as it goes in the first direction can be formed.

[0026] In the above barrier receiving portion, a tapered portion whose inner width increases as it goes in the second direction can be formed.

[0027] The tapered portion formed in the barrier member and / or the barrier receiving portion can guide the barrier member to be accurately inserted into the barrier receiving portion, and when the barrier member and / or the barrier receiving portion comprises a compressible material, the barrier member and / or the barrier receiving portion can be compressed in the width direction as the barrier member is inserted into the barrier receiving portion.

[0028] In order to ensure that the overlapping section is maintained even at the maximum displacement of the cover, the length of the overlapping section may be at least half of the separation distance between the upper surface of the cell stack and the inner surface of the cover.

[0029] The above barrier member and the barrier receiving portion may be provided in multiple pairs. In this case, the closer the pair of the barrier member and the barrier receiving portion is to the widthwise center, the longer the overlapping section may be. This is because, when the cover is deformed, the displacement in the first direction is greater, primarily in the area closer to the widthwise center of the cover.

[0030] Specifically, the length of the overlapping section of the barrier member and the barrier receiving portion closest to the center in the width direction among the plurality of pairs of barrier members may be at least half of the separation distance between the upper surface of the cell stack and the inner surface of the cover.

[0031] The present invention also provides a battery pack having the battery module built in and a structure of a vehicle having the battery pack built in.

[0032] The above battery modules may be integrated into a battery pack in multiple units to increase capacity and / or voltage. The battery pack may include a venting device capable of discharging gases and flames emitted when the battery module ignites to the outside. The battery pack may be incorporated into a vehicle as a power source. The vehicle may include an electric vehicle, a hybrid vehicle, and the like.

[0033] The present invention can provide a structure of a battery module in which a heat-resistant barrier member interposed between battery cells blocks heat transmission between cells.

[0034] Specifically, the present invention can provide a structure of a battery module in which the space between the cell stack and the housing is isolated by battery cell or cell bank unit to prevent high-temperature gas and flames emitted from the battery cells from transmitting heat between the battery cells.

[0035] The present invention also provides a structure of a battery module having a barrier member and a barrier receiving portion having variable overlapping sections so that the isolation structure is maintained even when the cover is deformed and heat propagation due to the propagation of gas and flame between cells can be blocked.

[0036] Another advantage of the present invention is that the compressibility of the barrier member and / or the barrier receiving portion allows for the absorption of assembly tolerances or swelling, and provides a battery module structure that is stable, variable in structure, and easy to manufacture.

[0037] In addition, the present invention may have various other effects, which will be described in each embodiment, or the description of effects that can be easily inferred by a person skilled in the art will be omitted.

[0038] Figure 1 shows the structure of a pouch-type battery cell.

[0039] Figure 2 shows the configuration of a cell stack.

[0040] Figures 3 and 4 show the structure of a typical battery module.

[0041] Figure 5 shows the structure of a battery module according to one embodiment of the present invention.

[0042] Figure 6 shows the structure of a barrier member and a barrier receiving portion according to one embodiment of the present invention.

[0043] Figure 7 shows the appearance of a battery module before the cover is bonded according to one embodiment of the present invention.

[0044] Figure 8 shows a cross-section of Figure 7.

[0045] Figure 9 shows the appearance of a battery module after the cover is combined according to one embodiment of the present invention.

[0046] Figure 10 shows a cross-section of Figure 9.

[0047] Figure 11 shows a main part of Figure 10.

[0048] Figure 12 shows a cross-section of a battery module after cover deformation according to one embodiment of the present invention.

[0049] Figure 13 shows the main part of Figure 12.

[0050] Figures 14 and 15 respectively show the appearance of a barrier receiving portion before and after deformation according to one embodiment of the present invention.

[0051] FIGS. 16 and 17 each illustrate the structure of a battery pack accommodating a battery module according to one embodiment of the present invention and a vehicle incorporating the battery pack.

[0052] [Explanation of symbols]

[0053] 1: Cell stack

[0054] 10: Cell Bank

[0055] 11: Battery cell

[0056] 110: Electrode assembly

[0057] 111: Pouch

[0058] 111S: Sealing part

[0059] 12: Absence of barrier

[0060] 120: Compressible pad

[0061] 121: Rigid plate

[0062] 122: Tapered section

[0063] 2: Busbar frame assembly

[0064] 3: Housing

[0065] 30: Module Frame

[0066] 31: Cover

[0067] 32: End plate

[0068] 4: Barrier Receptacle

[0069] 40: Connection

[0070] 41: Side wall

[0071] 42: Overlapping section

[0072] 420: Compressible pad

[0073] 421: Rigid plate

[0074] 422: Tapered section

[0075] M: Battery module

[0076] P: Battery pack

[0077] V: Car

[0078] L0: Separation distance

[0079] L1: First length

[0080] L2: Second length

[0081] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0082] Although the terms "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0083] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0084] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0085] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0086] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0087] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C to D", this means C or more and D or less, unless otherwise stated.

[0088] Hereinafter, a preferred embodiment of the present invention will be described with reference to the attached drawings.

[0089]

[0090] [Structure of battery cells and cell stacks]

[0091] Hereinafter, with reference to FIGS. 1 and 2, the structure of a battery cell according to one embodiment of the present invention and the structure of a cell laminate in which the cells are laminated will be described in detail.

[0092] Figure 1 illustrates the structure of a pouch-type battery cell. Referring to this, a battery cell (11) according to one embodiment of the present invention may be a pouch-type battery cell including an electrode assembly (110) and a pouch (111) that accommodates and seals the electrode assembly (110). However, the structure of the battery cell (11) is not limited to a pouch type.

[0093] The above pouch (111) may be folded to surround the electrode assembly (110) and sealed at a sealing portion (111S) on one side thereof. The sealing may be achieved by fusion, and thus may be melted by high heat. Therefore, if the battery cell (11) catches fire due to a short circuit or the like, there is a high possibility that high-temperature gas and flames will be discharged to the outside of the pouch (111) through the sealing portion (111S).

[0094] The battery cell (11) may include an electrode lead extending from the electrode assembly (110) and protruding outside the pouch (111). The electrode lead may electrically connect the electrode assembly (110) to the outside.

[0095] Figure 2 shows the configuration of a cell stack. Referring to this, a plurality of battery cells (11) can be stacked in the width direction to form a cell stack (1).

[0096] The above cell stack (1) may include a barrier member (12) interposed between the battery cells (11) to prevent heat transmission. The barrier member (12) may prevent direct heat conduction between the battery cells (11) and may prevent gas and flame from propagating in the width direction between the battery cells (11).

[0097] It is preferable that the above barrier member (12) include a heat-resistant material to withstand high heat.

[0098] According to the present embodiment, the barrier member (12) can protrude a predetermined length in the first direction compared to the upper surface of the cell stack (1). Since the barrier member (12) protrudes into the space between the cell stack (1) and the cover, heat transmission between the battery cells (11) can be prevented by allowing gas and flame to propagate through the space. In particular, since high-temperature gas and flame can melt the fusion of the sealing portion (111S), it is important to prevent the gas and flame from propagating through the space in the first direction of the cell stack (1).

[0099] The above battery cells (100) can be grouped one or more to form a plurality of cell banks (10) isolated by the barrier member (110). At this time, the barrier member (12) can prevent heat transmission between the cell banks (10).

[0100] One or more of the above barrier members (12) may be provided.

[0101]

[0102] [Rough structure of a battery module]

[0103] Hereinafter, with reference to FIG. 5, the general structure of a battery module according to one embodiment of the present invention will be described in detail.

[0104] Fig. 5 illustrates the structure of a battery module according to one embodiment of the present invention. Referring to this, the cell stack (1) can be accommodated in a housing (3) to form a battery module (M).

[0105] A busbar frame assembly (2) can be coupled to one longitudinal side of the above cell stack (1).

[0106] The above busbar frame assembly (2) can include a pair of terminals protruding outside the housing (3) so as to electrically connect the electrode leads to each other and electrically connect the entire cell stack (1) to the outside.

[0107] The above busbar frame assembly (2) may include a busbar frame constituting a main body, a slit through which the electrode lead passes, and a busbar through which the electrode lead passes through the slit and is connected.

[0108] The above housing (3) may include a module frame (30) having a bottom surface and a pair of side walls and accommodating the cell stack (1), a pair of end plates (32) covering the front and rear of the cell stack (1), and a cover (31) covering the first direction of the cell stack (1).

[0109] The cover (31) may be provided with a venting hole (not shown) for discharging gas and flame generated from the cell stack (1) in a first direction. It is preferable that a plurality of the venting holes (not shown) be provided to ensure structural rigidity of the cover (31) and smooth discharge of gas.

[0110] A barrier receiving portion (4) may be connected to the bottom surface of the cover (31). The barrier receiving portion (4) may extend in the longitudinal direction and have a groove shape facing a second direction opposite to the first direction so that one end of the barrier member (12) may be inserted.

[0111] The above barrier receiving portion (4) may be formed by the bottom surface of the cover (31) itself being sunken in the first direction, or may be formed integrally with the cover (31), or may be formed as a separate member that is connected by a method such as attachment to the bottom surface of the cover (31).

[0112] By inserting the barrier member (12) into the barrier receiving portion (4), the space between the housing (3) or at least the cell stack (1) and the cover (31) can be isolated in the width direction. Accordingly, the propagation of gas and flame through the space can be prevented. This can have the function of delaying or preventing thermal runaway of the module unit by preventing the propagation of heat between the battery cells (11).

[0113] The above barrier receiving portion (4) may be provided in a corresponding number of the barrier members (12), and may be provided to correspond to some of the barrier members (12). Accordingly, one or more of the above barrier receiving portions (4) may be provided, similar to the above barrier members (12).

[0114]

[0115] [Structure of barrier member and barrier receiving portion]

[0116] Hereinafter, with reference to FIG. 6, the structure of each of the barrier member and the barrier receiving portion according to one embodiment of the present invention and the combined structure thereof will be described in detail.

[0117] Fig. 6 illustrates the structure of a barrier member and a barrier receiving portion according to one embodiment of the present invention. Referring to this, the barrier receiving portion (4) may include a pair of side wall portions (41) that protrude in a second direction from both sides in the width direction of the barrier member (12). At this time, the barrier member (12) and the barrier receiving portion (4) may be fixedly coupled to each other by having one end of the barrier member (12) interposed between the pair of side wall portions (41). At this time, as described later, it is preferable that the barrier member (12) and the pair of side wall portions (41) are not restrained in the direction parallel to the first direction so as to be able to slide in the direction parallel to the first direction.

[0118] The above barrier receiving portion (4) may include a connecting portion (40) connected to the bottom surface of the cover (31) and having one end of the pair of side wall portions (41) connected to each of the widthwise ends thereof. As will be described later, the connecting portion (40) is preferably made of a flexible body so as to be deformed together with the bending deformation of the cover (31). That the connecting portion (40) is made of a flexible body may be a relative concept meaning that the bending strength of the connecting portion (40) is lower than the bending strength of the cover (31), and the connecting portion (40) may be interpreted as a rigid body in terms of its yield strength.

[0119] According to the present embodiment, the barrier receiving portion (4) may have a shape that is open in the second direction as a whole by including a connecting portion (40) attached to the cover (31) and a pair of side wall portions (41) extending in the second direction from both widthwise ends of the connecting portion (40).

[0120] The above barrier member (12) and / or the barrier receiving portion (4) may be formed as a laminated structure of multiple layers having different materials.

[0121] The barrier member (12) and / or the barrier receiving portion (4) may include a compressible material. Preferably, the barrier member (12) and / or the barrier receiving portion (4) may be compressed in the width direction as the barrier member (12) is inserted into the barrier receiving portion (4). Accordingly, the barrier member (12) and the barrier receiving portion (4) may exchange width-direction elastic restoring forces with each other, and may be brought into closer contact with each other, thereby being structurally stable and more reliably blocking the movement path of gas and flame.

[0122] In addition, this can reduce the possibility of a gap occurring due to assembly tolerance between the barrier member (12) and the barrier receiving portion (4). When the barrier member (12) includes a compressible material, it has the advantage of being able to absorb assembly tolerances between the battery cells (11) and / or between the cell stack (1) and the module frame (30), and also being able to absorb swelling of the battery cells (11).

[0123] The barrier member (12) and / or the barrier receiving portion (4) may include a rigid plate (121, 421). The rigid plate (121, 421) may have a predetermined yield strength, and thus may have the ability to resist deformation, particularly due to a bending load. However, it is preferable that the bending strength of the rigid plate (121, 421) is lower than that of the cover (31). The rigid plate (121, 421) can reinforce the structural rigidity of the barrier member (12) and / or the barrier receiving portion (4), thereby preventing deformation of the barrier member (12) and / or the barrier receiving portion (4) due to high-pressure gas, etc., and can reinforce the bond between the barrier member (12) and the barrier receiving portion (4).

[0124] The rigid plate (121, 421) may constitute the outermost part of the barrier member (12) and / or the barrier receiving portion (4). At this time, the rigid plate (121, 421) is preferably made of a material having heat resistance and / or insulation. Accordingly, the rigid plate (121, 421) can prevent short circuits between the battery cells (11) and maintain structural rigidity without being deformed even when the battery cells (11) catch fire.

[0125] According to the present embodiment, the barrier member (12) and the barrier receiving portion (4) may be formed as a triple-layer structure in which rigid plates (121, 421) having insulating and heat resistance are laminated on both sides of a compressible pad (120, 420) including a compressible material. At this time, the barrier receiving portion (4) may be formed by bending a member having the same triple-layer structure as the barrier member (12) twice at different points.

[0126] Fig. 7 shows a state before the cover is coupled to the battery module according to one embodiment of the present invention, and Fig. 8 shows a cross-section of Fig. 7. In addition, Fig. 9 shows a state after the cover is coupled to the battery module according to one embodiment of the present invention, and Fig. 10 shows a cross-section of Fig. 9. Referring to these drawings, the barrier member (12) and the barrier receiving portion (4) can be coupled to each other as the cover (31) and the module frame (30) are coupled to each other in a direction parallel to the first direction. Specifically, at this time, one end of the barrier member (12) can be inserted into the barrier receiving portion (4) from the second direction.

[0127] A tapered portion (122) whose width becomes narrower as it goes in the first direction may be formed at one end of the barrier member (12). The tapered portion (122) may guide one end of the barrier member (12) to be accurately inserted into the barrier receiving portion (4) when the cover (31) and the module frame (30) are coupled.

[0128] In the above barrier receiving portion (4), a tapered portion (422) whose inner width increases as it goes in the second direction can be formed. The tapered portion (422) can guide one end of the barrier member (12) to be accurately inserted into the barrier receiving portion (4) when the cover (31) and the module frame (30) are combined.

[0129] According to the present embodiment, the widthwise thickness of the barrier member (12) before compression may be greater than the inner width of the barrier receiving portion (4), and the barrier member (12) and / or the barrier receiving portion (4) may be compressed in the widthwise direction as the barrier member (12) is inserted into the barrier receiving portion (4) according to the guidance of the tapered portion (122, 422).

[0130] In the case where the barrier member (12) and / or the barrier receiving portion (4) are formed in a multi-layer structure as in the present embodiment, it is preferable that the tapered portion (122, 422) be provided on the outermost rigid portion of the barrier member (12) and / or the barrier receiving portion (4).

[0131]

[0132] [Barrier absence and barrier receiving area heat transmission prevention effect]

[0133] Hereinafter, with reference to FIGS. 10 to 13, the heat transmission prevention effect of a barrier member and a barrier receiving portion according to one embodiment of the present invention will be described in detail.

[0134] Figures 10 and 11 respectively illustrate a cross-section of a battery module before cover deformation according to one embodiment of the present invention and its main parts. Referring to these drawings, the barrier member (12) and the barrier receiving portion (4) isolate the separation space formed between the cell stack (1) and the cover (31) in the width direction, thereby preventing gas and flames emitted from the battery cell (11) from transmitting heat to other battery cells through the separation space.

[0135] According to the present embodiment, the sealing portion (111S) may be melted by high heat as it is fused and sealed, and thus the sealing portion (111S) becomes a weak point of the pouch (111), so when the battery cell (11) catches fire, gas and flame generated from the electrode assembly (110) are likely to be discharged in the first direction in which the sealing portion (111S) is provided, and therefore, isolating the separation space in the first direction of the cell stack (1) is effective in blocking heat transmission between the battery cells (11).

[0136] Figures 12 and 13 each illustrate a cross-section of a battery module cover after deformation according to an embodiment of the present invention and its main parts. Referring to these drawings, the cover (31) may be deformed by high heat and / or high pressure due to gas or flames generated within the battery module (M), or may be deformed by external impact, etc. In particular, the cover (31) may be bent or expanded so that its widthwise center is curved in the first direction. In this case, the distance between the cover (31) and the cell stack (1) may increase.

[0137] Referring again to FIG. 11, the barrier member (12) and the barrier receiving portion (4) may have an overlapping section (42) that overlaps each other in the width direction over a predetermined length parallel to the first direction.

[0138] The above-mentioned overlapping section (42) may have a length of at least half the distance (L0) between the cell stack (1) and the cover (31), taking into account the maximum degree of deformation of the cover (31).

[0139] When the barrier member (12) and the barrier receiving portion (4) are provided in multiple pairs, the length of the overlapping section (42) may be greater the closer the barrier member (12) and the barrier receiving portion (4) are to the widthwise center of the battery module (M). This is because, when the cover (31) is deformed as described above, the displacement of the widthwise center of the cover (31) is the greatest.

[0140] In this case, among the barrier member (12) and the barrier receiving portion (4), the overlapping section (42) of the one closest to the widthwise center of the battery module (M) may have a first length (L1) that is at least half the separation distance (L0). At this time, among the barrier member (12) and the barrier receiving portion (4), the overlapping section (42) of the one located at the outermost widthwise side of the battery module (M) may have a second length (L2) that is smaller than the first length (L1).

[0141] Referring back to FIGS. 12 and 13, as the cover (31) is deformed, the barrier member (12) and the barrier receiving portion (4) can slide away from each other. At this time, as the overlapping section (42) is formed, the bond between the barrier member (12) and the barrier receiving portion (4) may not be released despite the deformation of the cover (31), and the barrier member (12) and the barrier receiving portion (4) can still isolate the separation space in the width direction. Accordingly, even in a situation where the cover (31) is deformed, heat transmission between the battery cells (11) can be prevented, thereby delaying or blocking thermal runaway.

[0142] To this end, it is preferable that the barrier receiving portion (4) and the barrier member (12) are not restrained in a direction parallel to the first direction except for frictional force, but alternatively, the barrier receiving portion (4) and the barrier member (12) may be secured to each other by an adhesive that is easily detached by a frictional force below a predetermined level or a fusion agent that is easily melted by high heat.

[0143]

[0144] [Effects of deformation of the barrier receptacle]

[0145] Hereinafter, with reference to FIGS. 14 and 15, the effect of deformation of a barrier receiving portion according to one embodiment of the present invention will be described in detail.

[0146] Figures 14 and 15 respectively illustrate the appearance of a barrier receiving portion before and after deformation according to an embodiment of the present invention. Referring to these drawings, the connecting portion (40) may be formed of a flexible body that is flexibly deformed together with the deformation of the cover (31). As described above, the fact that the connecting portion (40) is formed of a flexible body may be a relative concept meaning that the flexural strength of the connecting portion (40) is lower than the flexural strength of the cover (31), and the connecting portion (40) may be interpreted as a rigid body in terms of its yield strength.

[0147] As the above connecting portion (40) is bent and deformed together with the deformation of the cover (31), the lower portion of the side wall portion (41) can be gathered inward. Accordingly, the side wall portion (41) can press both widthwise side surfaces of the barrier member (12) to be more strongly adhered to the barrier member (12), and the barrier member (12) and the barrier receiving portion (4) can more reliably isolate the separation space.

[0148] In this embodiment, since the barrier member (12) includes the compressible pad (120, 420), when the side wall portion (41) strongly presses both sides of the barrier member (12) due to deformation of the connecting portion (40), the compressible pad (120, 420) is additionally compressed, thereby allowing the barrier member (12) and the barrier receiving portion (4) to be brought into closer contact with each other with a stronger elastic restoring force. In contrast, when the barrier member (12) does not include a compressible material, the barrier member (12) and the barrier receiving portion (4) can be brought into closer contact with each other due to the elastic force caused by the bending deformation of the side wall portion (41).

[0149]

[0150] [Battery pack and vehicle structure]

[0151] Hereinafter, with reference to FIGS. 16 and 17, a structure of a battery pack accommodating a battery module according to one embodiment of the present invention and a vehicle incorporating the same will be described.

[0152] Figures 16 and 17 illustrate the structure of a battery pack accommodating a battery module according to one embodiment of the present invention and a vehicle incorporating the battery pack, respectively. Referring to these drawings, a plurality of battery modules (M) may be integrated to form a battery pack (P) in order to increase the capacity and / or voltage thereof. The battery pack (P) may include a venting device capable of discharging gases and flames emitted when the battery module (M) ignites to the outside. The battery pack (P) may be incorporated into a vehicle (V) as a power source. The vehicle (V) may include an electric vehicle, a hybrid vehicle, etc.

[0153]

[0154] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0155] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. A cell laminate in which a plurality of battery cells and a barrier member interposed between the battery cells are laminated in the width direction; A housing including a module frame accommodating the cell stack and a cover covering a first direction intersecting the width direction of the module frame; and It includes a barrier receiving portion connected to the inner surface of the cover and having a shape open in a second direction opposite to the first direction, into which the first direction side end of the barrier member is inserted; The above barrier member and the barrier receiving portion have an overlapping section that overlaps in the width direction over a predetermined length parallel to the first direction, A battery module in which the barrier member and the barrier receiving portion are slidable in a direction parallel to the first direction while maintaining contact with each other.

2. In claim 1, A battery module wherein the barrier member comprises a heat-resistant material.

3. In claim 1, A battery module wherein the barrier member protrudes in a first direction compared to the cell stack.

4. In claim 1, A battery module, wherein the barrier member comprises a compressible material.

5. In claim 4, A battery module, wherein the barrier member comprises a compressible pad including a compressible material and a pair of rigid plates laminated on both sides of the compressible pad in the width direction.

6. In claim 5, A battery module, wherein the rigid plate comprises a heat-resistant material.

7. In claim 1, A battery module, wherein the barrier receiving portion includes a pair of side wall portions that protrude in a second direction from both sides of the width direction of the barrier member and extend in the length direction.

8. In claim 7, A battery module, wherein the side wall portion includes a compressible material.

9. In claim 8, Each of the above side walls comprises a compressible pad including a compressible material and a rigid plate including a heat-resistant material, the battery module.

10. In claim 9, A battery module in which, in each of the above side walls, the rigid plates are provided as a pair laminated on both sides in the width direction of the compressible pad.

11. In claim 7, The above barrier receiving portion is provided on the inner surface of the cover and includes a connecting portion in which one end of the pair of side wall portions is connected to each of the widthwise ends thereof, A battery module wherein the above connecting portion is made of a flexible body that deforms together with the cover as it deforms.

12. In claim 1, A battery module, wherein a tapered portion is formed at the first direction side end of the above barrier member, the width of which becomes narrower as it goes in the first direction.

13. In claim 1, A battery module in which a tapered portion is formed in the barrier receiving portion, the inner width of which increases as it goes in the second direction.

14. In claim 1, The above barrier member and the barrier receiving portion are provided in multiple pairs, A battery module in which the length of the overlapping section is greater the closer the pair of the barrier member and the barrier receiving portion is to the center in the width direction.

15. In claim 1, A battery module, wherein the length of the above-mentioned overlapping section is at least half the distance between the upper surface of the cell stack and the inner surface of the cover.

16. In claim 14, A battery module, wherein, among the plurality of pairs of barrier members and the barrier receiving portions, the length of the overlapping section of the one closest to the center in the width direction is at least half the distance between the upper surface of the cell stack and the inner surface of the cover.

17. A battery pack comprising a battery module according to any one of claims 1 to 16.

18. A vehicle comprising the battery pack of claim 17.

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