Pouch-type battery cells

Abstract

The present invention relates to a battery cell and a battery module structure including the battery cell, which prevent heat transfer to adjacent battery cells in the event of a fire and guide vents downward. The battery cell includes an electrode assembly, a pouch that houses the electrode assembly, is folded in half, and is sealed on three sides except for the folded side, and electrode leads extending from the electrode assembly and protruding outside the pouch. The battery cell also includes a box-shaped insulating, heat-resistant, and fire-resistant shielding member that is open on one side and has a slit-shaped lead hole, and the electrode leads protrude outside the shielding member through the lead hole, so that five sides except for the folded side are covered by the shielding member.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0123603 dated September 28, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a pouch-type battery cell, and more particularly to a pouch-type battery cell that can block heat and flame propagation and guide the direction of venting. [Background technology]

[0003] Secondary batteries, which are easily applicable to various products and have electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles or hybrid vehicles powered by electrical sources, power storage devices, etc. These secondary batteries are attracting attention as a new energy source because they not only have the primary advantage of dramatically reducing the use of fossil fuels, but also because they are environmentally friendly and improve energy efficiency by not producing any by-products from energy use.

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

[0005] Since it is desirable to manufacture medium- to large-sized battery modules with small size and weight if possible, prismatic batteries and pouch-shaped batteries, which can be stacked with high density and have a small weight relative to their capacity, are mainly used as battery cells for medium- to large-sized battery modules.

[0006] 1 and 2 are perspective and exploded perspective views showing a battery module including pouch-type battery cells. Referring to these drawings, the battery module 1 may include a battery cell stack 11 formed by stacking a plurality of battery cells, and a housing 12 that houses the battery cell stack 11.

[0007] FIG. 3 is a perspective view showing a pouch-type battery cell. Referring to FIG. 3, the battery cell 2 may include an electrode assembly, a pouch 22 that houses the electrode assembly, and an electrode lead 21 that extends from the electrode assembly and protrudes outside the pouch 22. The pouch 22 may be formed by folding a pouch sheet made of a metal foil material around the electrode assembly and sealing three sides of the pouch 22 except for the folded side. Accordingly, the pouch 22 may include a first sealed portion 221a on the side opposite the folded side and second sealed portions 221b on the other two sides. After the first sealed portion 221a is sealed, its edge may be folded and resealed by taping, for example. The pouch sheet may be sealed at the second sealed portion 221b via the electrode lead 21.

[0008] Meanwhile, there is a risk that the battery cell 2 may overheat and ignite due to a short circuit or other cause. If the battery cell 2 ignites, heat, flame, and vent gas generated by vaporization of the electrolyte charged inside the pouch 22 may be emitted from the battery cell 2. In addition, the heat and flame caused by the ignition of the battery cell 2 may spread to other adjacent battery cells 2, causing a chain reaction of fires.

[0009] 4 is a schematic diagram showing how venting occurs in a pouch-type battery cell. Referring to this, the heat, flame, and vent gas can be discharged from the battery cell 2 mainly through the seal portion 221 of the pouch 22. Meanwhile, referring again to FIGS. 1 and 2, the battery cell 2 can be housed in the housing 12 with its folded surface facing downward, thereby allowing the heat, flame, and vent gas to be discharged mainly toward the top of the battery module 1.

[0010] However, in particular in electric vehicles, the battery modules are generally installed on the underside of the vehicle in the form of a battery pack in which multiple modules are integrated, and therefore, if heat, flames, and vent gases are emitted upward from the battery modules, this can pose a significant risk to passengers.

[0011] Therefore, there is an urgent need for a solution for each battery cell or battery module that can prevent heat transfer between the battery cells and direct the discharge of flames and vent gas downward. Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention was conceived in light of the background of the prior art described above, and aims to provide a battery cell and battery module structure that can guide vents downward in the event of thermal runaway.

[0013] Another object of the present invention is to provide a battery cell and battery module structure that can prevent heat transfer between adjacent battery cells and prevent chain fires.

[0014] Yet another technical object of the present invention is to provide a battery cell and battery module structure that maintains the energy density of existing battery modules without changing the design and production facilities of existing battery cells and battery modules, and that is equipped with safety measures in case of thermal runaway as described above.

[0015] The technical object of the present invention is not limited to the above-mentioned objects, and other unmentioned objects and advantages of the present invention can be understood from the following description and can be more clearly understood from the examples of the present invention. Furthermore, it can be easily understood that the objects and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0016] In order to solve the above problems, the present invention provides a battery cell structure including an electrode assembly, a pouch that houses the electrode assembly, is folded in half, and is sealed on three sides excluding the folded side, and an electrode lead that extends from the electrode assembly and protrudes outside the pouch, the battery cell structure including a box-shaped insulating, heat-resistant, and fire-resistant shielding member that is open on one side and has a slit-shaped lead hole, the electrode lead protruding outside the shielding member through the lead hole, and five sides excluding the folded side are covered by the shielding member.

[0017] In the following, the length, width and height of the blocking member are designated as X, Y and Z, respectively.

[0018] The blocking member can be manufactured by folding a single developed blocking material sheet into the box shape.

[0019] The sheet of insulating material may include a folder portion and a wing portion.

[0020] The folder section may be rectangular with width and length of X and Y+2Z, respectively.

[0021] The holder may correspond to one side of the battery cell in a height direction and both side surfaces of the battery cell in a thickness direction.

[0022] The wing portion may be a rectangle whose width and length are Y and Z, respectively. Alternatively, the wing portion may be a rectangle whose width and length are Z and Y, respectively.

[0023] The wing portions may be formed to protrude from both sides of the folder portion in a horizontal direction.

[0024] The wing portions may correspond to both side surfaces of the battery cell in the longitudinal direction.

[0025] The insulating member may be formed by folding the insulating material sheet to surround the battery cell, and then connecting adjacent edges of the insulating material sheet with adhesive tape, rather than connecting the adjacent edges with adhesive tape.

[0026] The adhesive tape may be formed from a heat and fire resistant material.

[0027] The sheet of insulating material may include adhesive feathers.

[0028] The adhesive wings may be formed so that when the insulating material sheet is folded to surround the battery cell, they are not connected to each other, but protrude from one of the adjacent edges and are folded over to cover and adhere to the other edge.

[0029] The blocking member may be a one-piece box-like member with all edges connected to each other.

[0030] The insulating member can be manufactured by folding a single, unfolded sheet of insulating material and fusing together adjacent edges that are not joined together.

[0031] The electrode leads may protrude from both longitudinal sides of the battery cell, and the lead holes may be formed on both longitudinal side surfaces of the blocking member and extend in the height direction up to the lower end of the blocking member.

[0032] The blocking member can be placed over the battery cell by inserting the battery cell into the open side of the blocking member, and the electrode leads can be inserted along the lead holes from the lower ends of both longitudinal sides of the blocking member.

[0033] After the battery cell is inserted into the blocking member, adhesive tape may be attached to lower ends of both longitudinal sides of the blocking member.

[0034] The adhesive tape may be formed from a heat and fire resistant material.

[0035] A sealant may be provided in the gap between the lead hole and the electrode lead to seal the gap.

[0036] The sealant may be a heat and fire resistant resin.

[0037] The present invention also provides a battery module structure including a battery cell stack formed by stacking a plurality of the battery cells, each including the blocking member, and a housing for accommodating the battery cell stack.

[0038] The blocking member may be made of a compressible material, and in this case, the blocking member can be interposed between the battery cells to absorb swelling and tolerances.

[0039] The battery cell stack may be accommodated in the housing such that the open direction of the blocking member faces downward.

[0040] The housing may have a bottom surface provided with a vent hole that opens downward.

[0041] The vent hole may be opened by an increase in internal pressure of the housing. [Effects of the Invention]

[0042] The present invention provides a battery cell structure in which heat transfer between adjacent battery cells is prevented by surrounding five sides of the battery cell with a blocking member that is open at the bottom, thereby preventing chain fires and guiding vents downward.

[0043] The present invention also provides a battery cell structure in which the blocking member is integrally formed, thereby maintaining its box shape despite a sudden increase in internal pressure in the event of a battery cell fire, thereby enabling the vent induction performance to be exerted.

[0044] Yet another advantage of the present invention is that it is possible to provide a battery cell and battery module structure that can withstand the above-mentioned sudden increase in internal pressure using only a shielding member made of a thin shielding material sheet, without adding a separate casing member, thereby eliminating the need to change the design and production facilities of existing battery cells and battery modules and maintaining the energy density of existing battery modules.

[0045] Yet another advantage of the present invention is that tolerances and swelling can be accommodated by using a compressible isolating member.

[0046] In addition to the above, the present invention can achieve various other effects, which will be explained in each embodiment, or explanations of effects that can be easily inferred by ordinary engineers will be omitted. [Brief explanation of the drawings]

[0047] [Figure 1] FIG. 1 is a perspective view showing a battery module including pouch-type battery cells. [Figure 2] FIG. 1 is an exploded perspective view showing a battery module including pouch-type battery cells. [Figure 3] FIG. 1 is a perspective view showing a pouch-type battery cell. [Figure 4] FIG. 1 is a schematic diagram showing how venting occurs in a pouch-type battery cell. [Figure 5] 1 is a perspective view showing a battery cell equipped with a blocking member according to the present invention; [Figure 6] 1 is a perspective view showing a blocking material sheet according to a first embodiment of the present invention. [Figure 7] 3 is a schematic diagram showing how the insulating material sheet according to the first embodiment of the present invention is folded while surrounding the battery cell. FIG. [Figure 8] 1 is a perspective view showing a battery cell equipped with a blocking member according to a first embodiment of the present invention. [Figure 9] FIG. 10 is a perspective view showing a blocking material sheet according to a second embodiment of the present invention. [Figure 10]10 is a schematic diagram showing how a blocking material sheet according to a second embodiment of the present invention is folded while surrounding a battery cell. FIG. [Figure 11] FIG. 10 is a perspective view showing a battery cell equipped with a blocking member according to a second embodiment of the present invention. [Figure 12] FIG. 10 is a perspective view showing a blocking material sheet according to a third embodiment of the present invention. [Figure 13] 10 is a schematic diagram showing how a blocking material sheet according to a third embodiment of the present invention is folded while surrounding a battery cell. FIG. [Figure 14] FIG. 10 is a perspective view showing a battery cell equipped with a blocking member according to a third embodiment of the present invention. [Figure 15] FIG. 10 is a perspective view showing a blocking member according to a fourth embodiment of the present invention. [Figure 16] FIG. 10 is a schematic diagram showing a state in which a battery cell is inserted into a blocking member according to a fourth embodiment of the present invention. [Figure 17] FIG. 10 is a perspective view showing a battery cell equipped with a blocking member according to a fourth embodiment of the present invention. [Figure 18] 1 is a schematic diagram showing how venting occurs in a battery cell equipped with a blocking member according to the present invention. [Figure 19] 1 is a front cross-sectional view showing a battery module including a battery cell having a blocking member according to the present invention; [Figure 20] 1 is a side cross-sectional view showing a battery module including a battery cell having a blocking member according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0048] The above-mentioned 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 implement the technical concept of the present invention. In describing the present invention, if a detailed description of known technologies relating to the present invention is deemed to obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

[0049] Although terms such as "first" and "second" are used to indicate various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, the first component may also be the second component.

[0050] Throughout the specification, unless otherwise specified, each element may be singular or plural.

[0051] Hereinafter, when an arbitrary structure is arranged "on top (or bottom)" of a component or "above (or below)" a component, it means that the arbitrary structure is not only arranged in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure arranged above (or below) the component.

[0052] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0053] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. Terms such as "comprise" or "include" in this application should not be interpreted as including all of the components or steps described in the specification, but should be interpreted as meaning that some of the components or steps may not be included, or that additional components or steps may be included.

[0054] In the entire specification, "A and / or B" means A, B or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0055] For convenience, throughout this specification, the direction along the longest edge of a battery cell or battery module is referred to as the length direction (X1) of the battery cell, the direction along the normal to the widest surface of the battery cell is referred to as the thickness direction (Y1) of the battery cell, and the direction intersecting both X1 and Y1 is referred to as the height direction (Z1) of the battery cell. The length direction, thickness direction, and height direction of the battery cell may correspond to the length direction, width direction, and height direction of the battery module, respectively.

[0056] The length (X), width (Y), and height (Z) of the blocking member refer to the dimensions along the X1, Y1, and Z2 directions, respectively. Meanwhile, with regard to the dimensions of the blocking material sheet, the horizontal direction (X2) and the vertical direction (Y2) are directions that intersect with each other.

[0057] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

[0058] 3 is a perspective view showing a pouch-type battery cell. Referring to this, the battery cell 2 may include an electrode assembly, a pouch 22 that houses the electrode assembly, and an electrode lead 21 that extends from the electrode assembly and protrudes outside the pouch 22.

[0059] The pouch 22 may be formed by folding a pouch sheet made of a metal foil material in half around the electrode assembly, and sealing three sides except the folded side, so that the pouch 22 may include a first sealed portion 221a on the side opposite the folded side and second sealed portions 221b on the other two sides.

[0060] After the first sealing portion 221a is sealed, the end portion thereof may be folded and a sealing tape 221T may be attached thereto.

[0061] In the second sealed portion 221b, the pouch sheet may be sealed with the electrode lead 21 interposed therebetween.

[0062] However, there is a risk that the battery cell 2 may overheat and ignite due to a short circuit or other cause. If the battery cell 2 ignites, heat, flame, and vent gas generated by vaporization of the electrolyte filled inside the pouch 22 may be emitted from the battery cell 2. The heat and flame caused by the ignition of the battery cell 2 may spread to other adjacent battery cells 2, causing a chain reaction of fires. The sudden increase in internal pressure of the battery due to the chain reaction of fires and the generation of vent gas may lead to an explosion.

[0063] 4 is a schematic diagram showing how venting occurs in a pouch-type battery cell. Referring to this, the heat, flame, and vent gas may be discharged from the battery cell 2 primarily through the seal portion 221 of the pouch 22. Meanwhile, the battery cell 2 is generally housed in a battery module with its seal portion 221 facing upward and forward and backward. In this case, there is a risk that the heat, flame, and vent gas generated from the battery cell 2 may be transmitted to other adjacent battery modules within a single battery pack, and in the case of an electric vehicle, there is a risk of an explosion directed toward passengers.

[0064] Therefore, the present invention provides a battery cell structure having a blocking member that can block heat propagation and guide flames and vent gases in a specific direction in the battery cell.

[0065] 5 is a perspective view showing a battery cell having a blocking member according to the present invention. Referring to this figure, the battery cell 2 according to the present invention may be provided with a blocking member 3.

[0066] The blocking member 3 may be made of a heat-insulating, heat-resistant, and fire-resistant material. For example, the blocking member 3 may be made of a heat-insulating, heat-resistant, and fire-resistant synthetic resin material.

[0067] The blocking member 3 may be a box-shaped member with one side open. Hereinafter, the length, width and height of the blocking member 3 are designated as X, Y and Z, respectively.

[0068] The blocking member 3 may be provided with a lead hole 32 .

[0069] A plurality of lead holes 32 may be provided.

[0070] The battery cell 2 may have five sides excluding the folded side covered by the blocking member 3. In this case, the electrode leads 21 may protrude to the outside of the blocking member 3 through the lead holes 32.

[0071] [Example 1] 6 is a perspective view showing an insulating material sheet according to Example 1 of the present invention. Referring to this, the insulating member 3 can be manufactured by folding a single insulating material sheet 31 in a developed view into a box shape.

[0072] The insulating sheet 31 may be made of a heat-insulating, heat-resistant, and fire-resistant material. For example, the insulating sheet 31 may be made of a heat-insulating, heat-resistant, and fire-resistant synthetic resin material.

[0073] The insulating material sheet 31 may include a folder portion 311 and a blade portion 312 .

[0074] The folder part 311 according to this embodiment may be a rectangle whose width and length are X and Y+2Z, respectively.

[0075] The wing portion 312 according to this embodiment may be a rectangle whose width and length are Y and Z, respectively.

[0076] The wing portions 312 may be formed to protrude from both sides of the folder portion 311 in the horizontal direction.

[0077] The wing portion 312 may include a lead hole 32 .

[0078] 7 is a schematic diagram showing how the insulating material sheet according to the first embodiment of the present invention is folded while surrounding the battery cell. Referring to this, the folder portion 311 and the wing portion 312 of the insulating material sheet 31 according to this embodiment are folded sequentially to form the insulating member 3 that surrounds five sides of the battery cell 2.

[0079] The folding order of the folder part 311 and the wing part 312 is not important. For example, the folder part 311 and the wing part 312 may be folded alternately one side at a time.

[0080] The holder part 311 may correspond to one side surface of the battery cell 2 in the height direction and both side surfaces of the battery cell 2 in the thickness direction.

[0081] The wing portions 312 may correspond to both side surfaces of the battery cell 2 in the longitudinal direction.

[0082] In the process of folding the wing portions 312, the electrode leads 21 can pass through the lead holes 32. As a result, the electrode leads 21 may protrude outside the blocking member 3.

[0083] 8 is a perspective view showing a battery cell including a blocking member according to a first embodiment of the present invention. Referring to this figure, the blocking member 3 can be formed by folding the blocking material sheet 31 to surround the battery cell 2 and then connecting adjacent edges, without connecting them to each other, with adhesive tape 33. That is, the blocking member 3 according to this embodiment can be formed by connecting four edges, where both sides in the length direction and both sides in the thickness direction intersect, to each other with the adhesive tape 33.

[0084] The adhesive tape 33 may be made of a heat-resistant and fire-resistant material, for example, a heat-resistant and fire-resistant synthetic resin material.

[0085] A sealant may be provided in the gap between the lead hole 32 and the electrode lead 21 to seal the gap.

[0086] The sealant may be a heat and fire resistant resin.

[0087] 18 is a schematic diagram showing how venting occurs in a battery cell equipped with a blocking member according to the present invention. Referring to this diagram, the blocking member 3 according to this embodiment covers all five sides of the battery cell 2, preventing heat transfer from the battery cell 2 and directing flames and vent gases toward its opening.

[0088] In this case, the blocking member 3 according to this embodiment can be sealed by integrally connecting four sides of the surface corresponding to the first sealing portion 221a to each other and connecting each two sides of the surface corresponding to the second sealing portion 221b with the adhesive tape 33. As a result, the blocking material sheets 31 located on the front and side surfaces of the battery cells 2 can be prevented from falling off the battery cells 2 even when the internal pressure increases suddenly due to ignition.

[0089] Furthermore, since the wing portions 312 according to this embodiment are folded in the direction in which the electrode leads 21 extend, the electrode leads 21 can be easily inserted into the lead holes 32 during the folding process.

[0090] [Example 2] 9 is a perspective view showing an insulating sheet according to a second embodiment of the present invention. Referring to FIG. 9, the insulating sheet 31 according to this embodiment may include a folder portion 311 and a wing portion 312.

[0091] The folder part 311 according to this embodiment may be a rectangle whose width and length are X and Y+2Z, respectively.

[0092] The wing portion 312 according to this embodiment may be a rectangle with a width and a length of Z and Y, respectively.

[0093] The wing portions 312 may be formed to protrude from both sides of the folder portion 311 in the lateral direction at positions facing each other, or may be formed to protrude from both sides of the folder portion 311 in the lateral direction at positions that cross each other.

[0094] The wing portion 312 may include a lead hole 32 .

[0095] 10 is a schematic diagram showing how the insulating material sheet according to the second embodiment of the present invention is folded while surrounding the battery cell. Referring to this, the folder portion 311 and the wing portion 312 of the insulating material sheet 31 according to this embodiment are folded sequentially to form the insulating member 3 that surrounds five sides of the battery cell 2.

[0096] The folding order of the folder part 311 and the wing part 312 is not important. For example, the folder part 311 and the wing part 312 may be folded alternately one side at a time.

[0097] The holder part 311 may correspond to one side surface of the battery cell 2 in the height direction and both side surfaces of the battery cell 2 in the thickness direction.

[0098] The wing portions 312 may correspond to both side surfaces of the battery cell 2 in the longitudinal direction.

[0099] In the process of folding the wing portions 312, the electrode leads 21 can pass through the lead holes 32. As a result, the electrode leads 21 may protrude outside the blocking member 3.

[0100] 11 is a perspective view showing a battery cell including a blocking member according to a second embodiment of the present invention. Referring to this, the blocking member 3 can be formed by folding the blocking material sheet 31 to surround the battery cell 2, and then connecting adjacent edges by adhering adhesive tape 33 without connecting them to each other. That is, the blocking member 3 according to this embodiment can be formed by connecting four edges where both sides of the blocking material sheet 31 in the length direction intersect with each side in the thickness direction and one side in the height direction with the adhesive tape 33.

[0101] The adhesive tape 33 may be made of a heat-resistant and fire-resistant material, for example, a heat-resistant and fire-resistant synthetic resin material.

[0102] A sealant may be provided in the gap between the lead hole 32 and the electrode lead 21 to seal the gap.

[0103] The sealant may be a heat and fire resistant resin.

[0104] Referring further to FIG. 18, the blocking member 3 according to this embodiment covers all five sides of the battery cell 2, preventing heat transfer from the battery cell 2 and directing flames and vent gases toward its opening.

[0105] In this case, the blocking member 3 according to this embodiment may be sealed by integrally connecting two edges of each surface corresponding to the first sealing portion 221a and the second sealing portion 221b, and connecting the other two edges to each other with the adhesive tape 33. As a result, the blocking material sheets 31 located on the front and side surfaces of the battery cells 2 may not fall off from the battery cells 2 even when the internal pressure increases suddenly due to ignition.

[0106] Furthermore, the blocking member 3 according to this embodiment has an advantage that the required amount of adhesive tape 33 is even smaller than that of the first embodiment.

[0107] [Example 3] 12 is a perspective view showing an insulating sheet according to a third embodiment of the present invention. Referring to this, the insulating sheet 31 according to this embodiment may further include adhesive blades 313 in addition to the insulating sheet 31 of the first embodiment.

[0108] The adhesive blade 313 may be formed to protrude outward from at least one side of the insulating material sheet 31 .

[0109] The adhesive wings 313 may be provided on the wing portions 312 or on the folder portion 311. The adhesive wings 313 may also be provided on the wing portions 312 and the folder portion 311.

[0110] The adhesive wing 313 may be a rectangle such as a trapezoid, and preferably may be provided so as to protrude over the entire length of one side of the wing portion 312 and / or the folder portion 311, but any shape is acceptable as long as it is a protruding shape.

[0111] 13 is a schematic diagram showing how the insulating material sheet according to the third embodiment of the present invention is folded while surrounding the battery cell 2. Referring to this, the insulating material sheet 31 according to this embodiment may be folded while surrounding the battery cell 2, as in the first embodiment.

[0112] In this case, when the insulating material sheet 31 is folded to surround the battery cell 2, the adhesive wings 313 may not be connected to each other, but may protrude from one of the adjacent edges and be folded to cover and adhere the other edge.

[0113] The adhesive blade 313 may be directly adhered to the insulating material sheet 31 by its own adhesiveness or by an adhesive applied thereto, or may be adhered by an adhesive tape as described below.

[0114] The adhesive wings 313 may be folded so as to protrude from one side of the adjacent edges to the other side, or may be double-adhered by being folded so as to protrude from both sides to the other sides.

[0115] 14 is a perspective view showing a battery cell including a shielding member according to Example 3 of the present invention. Referring to this, the shielding member 3 according to this example can be formed by folding the adhesive wings 313 to form the shielding material sheet 31 into a box shape, and then adhering the adhesive wings 313 to the shielding material sheet 31 with adhesive tape 33.

[0116] The adhesive tape 33 may be made of a heat-resistant and fire-resistant material, for example, a heat-resistant and fire-resistant synthetic resin material.

[0117] A sealant may be provided in the gap between the lead hole 32 and the electrode lead 21 to seal the gap.

[0118] The sealant may be a heat and fire resistant resin.

[0119] Referring further to FIG. 18, the blocking member 3 according to this embodiment covers all five sides of the battery cell 2, preventing heat transfer from the battery cell 2 and directing flames and vent gases toward its opening.

[0120] The blocking member 3 of this embodiment has the advantage that, compared to Example 1, the adhesive wings 313 minimize gaps that may exist in the blocking member 3 and provide greater structural strength.

[0121] [Example 4] 15 is a perspective view showing a blocking member according to a fourth embodiment of the present invention. Referring to this figure, the blocking member 3 may be in the form of a single box in which all edges are connected to each other.

[0122] The insulating member 3 can be manufactured by folding a single insulating sheet 31 in a developed view into a box shape and fusing adjacent edges together without connecting them together. However, various methods can be used to connect adjacent edges together without connecting them together, such as attaching a heat-insulating, heat-resistant, and fire-resistant adhesive tape.

[0123] The insulating sheet 31 may be made of a heat-insulating, heat-resistant, and fire-resistant material. For example, the insulating sheet 31 may be made of a heat-insulating, heat-resistant, and fire-resistant synthetic resin material.

[0124] The lead holes 32 may be provided on both side surfaces of the blocking member 3 in the length direction.

[0125] The lead holes 32 may be provided so as to extend in the height direction up to the lower ends of both side surfaces of the blocking member 3 in the length direction.

[0126] 16 is a schematic diagram showing how a battery cell is inserted into a blocking member according to a fourth embodiment of the present invention. Referring to this diagram, the blocking member 3 can cover the battery cell 2 by inserting the battery cell 2 into the open surface of the blocking member 3.

[0127] At this time, the electrode leads 21 can be inserted along the lead holes 32 from the lower ends of both side surfaces of the blocking member 3 in the length direction.

[0128] 17 is a perspective view showing a battery cell having a blocking member according to Example 4 of the present invention. Referring to this figure, the blocking member 3 can be formed by inserting the battery cell 2 and then attaching adhesive tape 33 to the lower end portions of both sides in the length direction of the battery cell 2.

[0129] The adhesive tape 33 may be made of a heat-resistant and fire-resistant material, for example, a heat-resistant and fire-resistant synthetic resin material.

[0130] A sealant may be provided in the gap between the lead hole 32 and the electrode lead 21 to seal the gap.

[0131] The sealant may be a heat and fire resistant resin.

[0132] Referring further to FIG. 18, the blocking member 3 according to this embodiment covers all five sides of the battery cell 2, preventing heat transfer from the battery cell 2 and directing flames and vent gases toward its opening.

[0133] The blocking member 3 according to this embodiment surrounds the battery cell 2 with all five sides except the lower open side connected to each other at all edges to form a sealed seal, so that heat, flames, and vent gases generated in the battery cell 2 do not leak out and are only discharged downward.

[0134] Furthermore, the blocking member 3 according to this embodiment has the advantage that the amount of adhesive tape 33 required for complete sealing is very small.

[0135] The present invention also discloses a battery module structure including the battery cells including the blocking members as described above. Of course, the battery cells of Examples 1 to 4 can also be used to configure a battery module having the structure described below.

[0136] First, the structure of a general battery module will be described with reference to the drawings.

[0137] 1 and 2 are a perspective view and an exploded perspective view, respectively, of a battery module including pouch-type battery cells. Referring to these drawings, the battery module including pouch-type battery cells may include a battery cell stack formed by stacking a plurality of the battery cells 2, and a housing 12 that houses the battery cell stack 11.

[0138] The battery cell stack 11 can be formed by stacking a plurality of the battery cells 2 in the thickness direction.

[0139] The battery cell stack 11 may be formed by stacking a plurality of the battery cells 2 in the thickness direction with compressible pads interposed therebetween. The compressible pads are compression molded to fit the shape of the battery cells 2, thereby absorbing tolerances and swelling (the phenomenon in which the battery cell pouches bulge due to gas filling inside the pouches).

[0140] The housing 12 may include a "U"-shaped U-frame 123 that is open at the top and both longitudinal sides, end plates 122 that cover the front and rear of the U-frame 123, and a top plate 121 that covers the top of the U-frame.

[0141] The battery cell stack 11 can be housed in the housing with the folded surfaces of the battery cells 2 facing downward, that is, with the first seal portions 221a facing upward.

[0142] An insulating film may be interposed between the housing 12 and the battery cell stack 11 to insulate the battery cell stack 11 from the outside.

[0143] A thermally conductive resin that can conduct heat to the outside may be provided on the bottom surface of the U-frame 123 in order to cool the heat generated by the battery cell stack 11 .

[0144] Hereinafter, the structure of a battery module according to a preferred embodiment of the present invention will be described with reference to the drawings.

[0145] [Example 5] 19 and 20 are front and side cross-sectional views, respectively, showing a battery module including battery cells equipped with a blocking member according to the present invention. Referring to these drawings, the battery cells 2 are surrounded by the blocking member 3 and stacked in the thickness direction to form the battery cell stack 11.

[0146] The battery cells 2 may be stacked such that the opening directions of the blocking members 3 are aligned with each other to form the battery cell stack 11 .

[0147] The insulating member 3 may be made of a compressible material. This allows the insulating member 3 to absorb tolerances and swelling, just like the compressible pad. In this case, the insulating member 3 simply occupies the space that the compressible pad would have occupied. Therefore, the battery module 1 according to this embodiment can be manufactured by only slightly modifying the manufacturing process of the battery cell stack 11 in a battery module that uses an existing compressible pad, without changing the design or production equipment.

[0148] This is possible because the blocking member 3 has a unique integrated structure that allows it to maintain its box-like structure against strong internal pressure, even though it is made of the thin blocking material sheet 31.This is an advantage in that it is possible to implement the present invention by simply replacing the existing compressible pad with the blocking member 3, without the need to add a separate rigid casing or the like.

[0149] Another advantage of this embodiment is that when the battery module 1 can be manufactured without adding additional components as described above, the energy capacity relative to the number and volume of the battery cells 2 that can be accommodated in one battery module 1, i.e., the energy density, does not decrease compared to existing battery modules.

[0150] The battery cell stack 11 can be housed in the housing 12 so that the folded surfaces of the battery cells 2 and the open surfaces of the blocking members 3 face downward.

[0151] The insulating film 13 may be interposed between the battery cell stack 11 and the top plate 121 and both side walls of the housing 12 .

[0152] The thermally conductive resin 14 may be interposed between the battery cell stack 11 and the bottom surface of the housing 12 .

[0153] The bottom surface of the battery module 1 may be provided with a vent hole 124 that penetrates downward and opens. When the battery cell 2 ignites, the flame and vent gas guided downward by the blocking member 3 can be discharged to the outside of the battery module 1 through the vent hole 124. As a result, the flame and vent gas caused by the ignition of the battery cell 2 can be guided downward from the battery cell 2 unit to the battery module 1 unit.

[0154] In this case, the blocking member 3 can withstand the momentary increase in internal pressure caused by the vent gas from the battery cell 2, and the blocking member 3 may be made of a compressible material, thereby reducing the burden on the housing caused by the sudden increase in internal pressure. For example, if the vent is guided downward only at the battery module 1 level, there is a high possibility that the flame generated from the battery cell 2 will damage the insulating film 13 and the thermally conductive resin 14.

[0155] In particular, the end plates 122 may be provided with terminals that can electrically connect the battery cell stack 11 to the outside, mainly so that the battery module 1 can be connected to other adjacent battery modules to form a battery pack. However, venting at the battery module level heats the end plates 122, exposing them to flames and vent gases, making it very difficult to prevent heat transfer to adjacent battery modules. This can lead to a chain reaction of fires between battery modules within the battery pack, and the fires of the battery cells 2 can lead to even larger explosions. According to the present invention, such chain reaction of fires between battery modules can also be prevented.

[0156] Furthermore, the blocking member 3 can also prevent heat transfer between the battery cells 2, and therefore can prevent excessive thermal runaway caused by a chain reaction of fires among the battery cells 2 in the first place.

[0157] The vent hole 124 may be opened by an increase in the internal pressure of the housing 12. Alternatively, the vent hole 124 may be closed by a decrease in the internal pressure of the housing 12. In other words, the vent hole 124 may be openable and closable in response to an increase or decrease in the internal pressure of the housing 12.

[0158] It should be understood that the above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is defined by the following claims rather than the above detailed description. All modifications and variations within the meaning and scope of the following claims, as well as equivalent concepts, should be construed as being included within the scope of the present invention.

[0159] Although the present invention has been described above with reference to illustrative drawings, the present invention is not limited to the embodiments and drawings disclosed in this specification, and various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not explicitly described in the above description of the embodiments of the present invention, it is natural that the effects that can be predicted by the configuration should also be recognized. [Explanation of symbols]

[0160] 1 Battery Module 11 Battery cell stack 12 Housing 121 Top Plate 122 End Plate 123 U-frame 124 vent hole 13 Insulating film 14 Thermally conductive resin 2 battery cells 21 Electrode Lead 22 pouches 221 Seal part 221a First seal part 221b Second seal part 221T Sealing Tape 222 Protrusion 3. Blocking element 31 Insulating material sheet 311 Folder section 312 Wings 313 Adhesive feather 32 Lead hole 33 Adhesive Tape

Claims

1. electrode assembly; a pouch for containing the electrode assembly, the pouch being folded in half and sealed on three sides excluding the folded side; an electrode lead extending from the electrode assembly and protruding outside the pouch, A heat-insulating, heat-resistant and fire-resistant insulating member having a length, width and height of X, Y and Z, respectively, the insulating member having a box-like structure with one side open and provided with a slit-shaped lead hole; The electrode lead protrudes to the outside of the blocking member through the lead hole, and the blocking member covers five sides of the pouch except for the folded side of the pouch. Battery cell.

2. The blocking member is formed from a foldable sheet of blocking material. The battery cell according to claim 1 .

3. The insulating material sheet is A rectangular folder portion whose horizontal and vertical dimensions are X and Y+2Z, respectively; a rectangular wing portion having a width and a length of Y and Z, the wing portion protruding from both sides in the horizontal direction of the folder portion and having the lead hole formed therein; the holder portion corresponds to one side surface of the battery cell in a height direction and both side surfaces of the battery cell in a thickness direction; The wing portions correspond to both side surfaces of the battery cell in the longitudinal direction. The battery cell according to claim 2 .

4. The insulating material sheet is A rectangular folder portion whose horizontal and vertical dimensions are X and Y+2Z, respectively; a rectangular wing portion having a width and a length of Z and Y, the wing portion protruding from both sides in the horizontal direction of the folder portion and having the lead hole formed therein; the holder portion corresponds to one side surface of the battery cell in a height direction and both side surfaces of the battery cell in a thickness direction; The wing portions correspond to both side surfaces of the battery cell in the longitudinal direction. The battery cell according to claim 2 .

5. The insulating member is formed by folding the insulating material sheet to surround the battery cell, and then connecting adjacent edges of the folded insulating material sheet with adhesive tape, without connecting the edges together. The battery cell according to claim 2 .

6. The adhesive tape is formed from a heat-resistant and fire-resistant material. The battery cell according to claim 5 .

7. When the insulating material sheet is folded to surround the battery cell, the insulating material sheet includes adhesive wings that are not connected to each other but are folded to protrude from one of the adjacent edges and cover and adhere to the other edge. The battery cell according to claim 2 .

8. a sealant that seals a gap between the lead hole and the electrode lead; The battery cell according to claim 2 .

9. The sealing material is a heat-resistant and fire-resistant resin. The battery cell of claim 8 .

10. The blocking member is an integral box-like member in which all edges are connected to each other. The battery cell according to claim 2 .

11. Adjacent edges of the sheet of insulating material folded to form the insulating member are fused together. The battery cell of claim 10.

12. the electrode leads protrude from both sides of the battery cell in the longitudinal direction; the lead holes are formed on both longitudinal side surfaces of the blocking member, extending in the height direction to the lower end thereof; The battery cell of claim 10.

13. the battery cell is inserted into the open surface of the blocking member, whereby the blocking member covers the battery cell; Adhesive tapes are attached to the lower ends of both longitudinal sides of the blocking member. The battery cell of claim 12.

14. The adhesive tape is formed from a heat-resistant and fire-resistant material. The battery cell of claim 13 .

15. a sealant that seals a gap between the lead hole and the electrode lead; The battery cell of claim 10.

16. A battery cell stack formed by stacking a plurality of the battery cells according to any one of claims 1 to 15, and a housing that houses the battery cell stack. Battery module.

17. The blocking member is formed from a compressible material. The battery module according to claim 16.

18. The battery cell stack is accommodated in the housing so that the open direction of the blocking member faces downward. The battery module according to claim 16.

19. A vent hole that opens downward is provided on the bottom surface of the housing. The battery module according to claim 18.

20. The vent hole is opened by an increase in internal pressure of the housing. The battery module of claim 19.

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