Battery module, Battery pack and vehicle including the same

Abstract

A battery module according to the present invention comprises: a cell stack having a plurality of battery cells; a module case having a venting hole in a top plate provided to accommodate the cell stack and covering the upper portion of the cell stack; and a venting channel forming sheet coupled to the top plate and having a folding portion folded one or more times at a position corresponding to the venting hole, wherein the folding portion may be provided to unfold over the venting hole by a predetermined pressure to form a gas passage on the upper portion of the top plate.

Description

Technology Field

[0001] The present invention relates to a battery module, a battery pack including the same, and an automobile. Specifically, the present invention relates to a battery module capable of suppressing heat transfer between battery cells when a thermal event occurs in the battery module, a battery pack including the same, and an automobile. Background Technology

[0002] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric sources. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. When a high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Additionally, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or battery pack. Therefore, the number of battery cells included in the battery module or pack can be varied depending on the required output voltage or charge / discharge capacity.

[0004] Meanwhile, since battery cells involve chemical reactions during charging and discharging, their performance may degrade if used in environments higher than the optimal temperature; furthermore, if thermal control is not maintained at the appropriate temperature, there is a constant risk of unexpected ignition or explosion. Additionally, battery modules are structured to house these battery cells intensively within a module housing. Consequently, if a thermal event occurs in a single battery cell, the emitted high-temperature gases or flames can transfer to adjacent cells, potentially leading to a chain reaction of explosions, making this situation extremely dangerous.

[0005] Therefore, a battery module having a structure capable of suppressing and delaying thermal propagation is required so that even if a thermal event occurs in some battery cells within the battery module, high-temperature gases or flames are transferred to other battery cells within the battery module and cause thermal runaway. The problem to be solved

[0006] One objective of the problem to be solved by the present invention is to provide a battery module capable of preventing venting gases, etc., from propagating to other battery cells when a thermal event occurs in a battery cell, and guiding and discharging them in a specific direction.

[0007] The technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below. means of solving the problem

[0008] According to the present invention, a battery module may be provided comprising: a cell stack having a plurality of battery cells; a module case having a venting hole in a top plate provided to accommodate the cell stack and covering the upper portion of the cell stack; and a venting channel forming sheet coupled to the top plate and having a folding portion folded in one or more layers at a position corresponding to the venting hole, wherein the folding portion is unfolded over the venting hole by a predetermined pressure to form a gas passage on the upper portion of the top plate.

[0009] The above venting channel forming sheet may be disposed on the lower surface of the top plate facing the cell laminate.

[0010] The above-mentioned venting channel forming sheet can be made of a material having electrical insulation and fire resistance.

[0011] The above-mentioned venting channel forming sheet may include a first fixing part and a second fixing part fixed to the lower surface of the top plate with the folding part in between.

[0012] The first fixing part and the second fixing part may be bonded or bolted to the lower surface of the top plate.

[0013] It may include a first sheet fixing member that protrudes downward from the top plate and is connected to the first fixing part; and a second sheet fixing member connected to the second fixing part.

[0014] The first sheet fixing member and the second sheet fixing member have the same structure, and the first sheet fixing member may include a body penetrating the first fixing part and a support member formed at the bottom of the body to support the lower surface of the first fixing part.

[0015] The top plate may include N venting holes spaced apart along the stacking direction of the battery cells.

[0016] The above venting channel forming sheet may have a folding portion that corresponds one-to-one with N venting holes.

[0017] The above-described module case further includes a flame-retardant cover coupled to the upper part, and the flame-retardant cover may have an opening / closing part configured to rupture or at least partially separate due to a predetermined pressure or heat in an area corresponding to the venting hole of the top plate.

[0018] The above opening and closing part may be provided in a form formed by making a notch line or a shredding line in the flame-retardant cover.

[0019] The above module case may include a case body open at least on the upper surface; and a top plate that covers the upper surface of the case body and is coupled to the case body.

[0020] The above battery cells are pouch-type battery cells, and the pouch-type battery cells can be stacked in one direction.

[0021] According to another aspect of the present invention, a battery pack comprising the battery module described above may be provided.

[0022] According to another aspect of the present invention, a vehicle comprising the battery pack may be provided. Effects of the invention

[0023] The battery module according to the present invention includes a venting channel forming sheet so that when a thermal event occurs in a battery cell, venting gas, etc., is not propagated to other battery cells and can be guided and discharged in a specific direction.

[0024] The effects of the present invention are not limited to the effects described above, and unmentioned effects will be clearly understood by those skilled in the art from this specification and the attached drawings. Brief explanation of the drawing

[0025] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention. Figure 2 is an exploded perspective view of the battery module of Figure 1. FIG. 3 is a drawing showing the lower surface of a top plate to which a venting channel forming sheet according to one embodiment of the present invention is attached. Figure 4 is a cross-sectional view of a battery module according to A-A' of Figure 1. Figure 5 is a partial enlarged view of Figure 4. FIG. 6 is a drawing illustrating an example in which the folding part of the battery cell in the outermost region of FIG. 4 is unfolded during thermal runaway. FIG. 7 is a perspective view of a battery module having a gas passage formed corresponding to FIG. 6. FIG. 8 is a drawing illustrating an example in which the folding portion of the battery cell in the outermost region and the battery cell in the central region of the battery module of FIG. 4 is unfolded during thermal runaway. FIG. 9 is a perspective view of a battery module having a gas passage formed corresponding to FIG. 8. FIG. 10 is a partial cross-sectional view of a battery module according to another embodiment of the present invention. FIG. 11 is a drawing showing the folding part of FIG. 10 in an unfolded state. FIG. 12 is a partial cross-sectional view of a battery module according to another embodiment of the present invention. FIG. 13 is a drawing showing the folding part of FIG. 12 in an unfolded state. FIG. 14 is a perspective view of another battery module of the present invention. FIG. 15 is a perspective view of the battery module of FIG. 14 with the flame-retardant cover removed. FIG. 16 is a schematic diagram illustrating a battery pack according to one embodiment of the present invention. FIG. 17 is a schematic drawing illustrating an automobile according to one embodiment of the present invention. Specific details for implementing the invention

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely one preferred embodiment of the present invention and do not represent all of the technical spirit of the present invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0027] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0028] Since embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, the shapes and sizes of the components in the drawings may be exaggerated, omitted, or schematically depicted for clearer explanation. Accordingly, the size or proportion of each component does not entirely reflect the actual size or proportion.

[0029] FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention, FIG. 2 is an exploded perspective view of the battery module of FIG. 1, FIG. 3 is a drawing showing the lower surface of a top plate to which a venting channel forming sheet according to one embodiment of the present invention is attached, and FIG. 4 is a cross-sectional view of the battery module according to A-A' of FIG. 1.

[0030] Referring to FIGS. 1 to 4, a battery module (10) according to one embodiment of the present invention includes a cell stack (100), a module case (200), and a venting channel forming sheet (300).

[0031] The cell assembly is a collection of multiple battery cells (110). The battery cells (110) may be pouch-type battery cells (110).

[0032] The above pouch-type battery cell (110) may include an electrode assembly and a pouch case that accommodates the electrode assembly. The pouch case may accommodate the electrode assembly in a storage portion, and the edges around the storage portion may be heat-fused to form a sealing portion. The sealing portion may be provided on three of the four sides of the pouch case.

[0033] The above pouch-type battery cell (110) may be provided in an upright position with the side not containing the sealing portion facing downward. As shown in FIG. 2, a plurality of pouch-type battery cells (110) may be arranged side by side in the left-right direction (X-axis direction) while standing upright in the vertical direction (Z-axis direction). At this time, each battery cell (110) may have the sealing portion facing the front-back direction (Y-axis direction) and the upward direction (+Z-axis direction), and the storage portion facing the left-right direction (X-axis direction). By arranging the battery cells (110) in this way, it is easy to control the venting direction to one side, and cooling performance can be secured by performing edge cooling through the side not containing the sealing portion.

[0034] Additionally, the pouch-type battery cell (110) includes a pair of electrode leads (111) that are connected to an electrode assembly inside the pouch case and are drawn out to the outside of the pouch case to function as electrode terminals. The pair of electrode leads (111) may be arranged in opposite directions in the longitudinal direction (±Y direction) of the pouch-type battery cell (110). If necessary, the pouch-type battery cell (110) may have a form in which the two electrode leads (111) are located only at one end in the Y-axis direction, for example, at the end in the +Y-axis direction.

[0035] The present invention is not limited by the specific type or shape of the battery cell (110), and various battery cells (110) known at the time of filing the present invention may be employed. In this embodiment, a pouch-type battery cell (110) having high energy density and easy stacking is used as shown in the drawing, but a cylindrical or prismatic secondary battery may also be employed as the battery cell (110).

[0036] The cell laminate (100) according to the present embodiment may include a barrier member (120). The barrier member (120) may be provided in the form of a plate-like body that is thinner than the battery cell (110). For example, the barrier member (120) may be provided in the form of a pad having excellent heat and / or fire resistance and compressibility. A material such as silicone or aerogel may be used as the material for the barrier member (120).

[0037] The above barrier members (120) may be arranged in multiple numbers with a predetermined number of battery cells (110) in between along the direction in which the battery cells (110) are arranged. In particular, the barrier members (120) may be configured to partition the battery cells (110) into a predetermined number. For example, as shown in FIG. 4, a barrier member (120) may be arranged for every four battery cells (110) to group the battery cells (110) into groups of four.

[0038] According to the above embodiment of the present invention, the propagation of flame or heat can be blocked by the barrier member (120) during thermal runaway of the battery cell (110). In addition, the battery member can contribute to suppressing structural deformation of the module case (200) by absorbing the expansion force of the battery cell (110) during swelling of the battery cell (110).

[0039] Meanwhile, referring to FIG. 2, a battery module (10) according to one embodiment of the present invention may include a busbar frame assembly (400). The busbar frame assembly (400) may include a busbar frame (410) and a plurality of busbars (420) and may be positioned at the front and rear of the cell stack (100).

[0040] The busbar frame (410) can be injection molded from an electrically insulating material and can be provided in the form of a roughly plate-like body having a size that can cover the front (+Y direction) or rear (-Y direction) of the cell stack (100). Additionally, the busbar frame (410) may be provided with a plurality of lead slots that allow the electrode leads (111) of the battery cells (110) to pass through in the front-rear direction. The plurality of lead slots may be provided along the stacking direction of the battery cells (110). Additionally, the busbar frame (410) may be configured to allow a plurality of busbars (420) to be attached to its outer surface.

[0041] The plurality of busbars (420) may be provided with an electrically conductive material such as a metal, such as copper, aluminum, or nickel, as a means for connecting battery cells (110) in series and / or in parallel. The busbars (420) may be arranged on the busbar frame (410) along the same direction as the stacking direction of the battery cells (110). For example, the electrode lead (111) of the battery cell (110) may be drawn out to the outside of the busbar frame (410) through a lead slot and welded to a designated busbar (420).

[0042] The above module case (200) can preferably be made of a material with excellent mechanical strength as a component for protecting the cell stack (100) from external impacts, etc.

[0043] The above module case (200) may include a case body (210) and a top plate (220). The case body (210) may be configured so that at least the top surface is open. For example, the case body (210) may be configured so that the top surface, front surface, and rear surface are open. The case body (210) may be provided in the form of a so-called U-frame in which a bottom plate (211), a left side plate (212), and a right side plate (213) are formed integrally.

[0044] The top plate (220) is configured to cover the upper portion of the cell stack (100) and can be provided to be coupled with the case body (210). For example, the top plate (220) may be coupled by welding the two corner portions along the length direction to the top of the pair of side plates (212, 213). At this time, the combined form of the top plate (220) and the case body (210) may be a rectangular tubular shape with the front and rear sides open.

[0045] The above module case (200) may include end covers (230, 240) provided on the open front and rear of the case body (210). The end covers (230, 240) may be welded to the case body (210). Meanwhile, although not illustrated for convenience, the end covers (230, 240) may, for example, have an insulating material on the inside and a metal material on the outside. Additionally, the end covers (230, 240) may have holes or slits partially provided for the exposure of parts that need to be exposed to the outside, such as the positive terminal and negative terminal or connector of the battery module (10).

[0046] Meanwhile, the top plate (220) may be provided with a venting hole (221) for venting the venting gas to the outside of the module case (200) when the battery cell (110) ignites.

[0047] The top plate (220) may include N venting holes (221) spaced apart along the stacking direction of the battery cells (110). As shown in FIG. 2, the venting holes (221) may be provided at predetermined intervals in the width direction (X direction) of the top plate (220). The venting holes (221) may preferably be provided in the form of elongated holes with a larger diameter in the length direction of the top plate (220). Additionally, the venting holes (221) may be provided at predetermined intervals in the length direction of the top plate (220).

[0048] The top plate (220) may be provided with venting holes (221) arranged in a roughly matrix structure. For example, the top plate (220) of the present embodiment may be said to have venting holes (221) in a 6-row, 3-column structure. However, it is sufficient that the venting holes (221) according to the present invention are configured to be spaced apart in the width direction (X-direction) of the top plate (220). That is, the venting holes (221) do not necessarily need to be divided in the length direction (Y-direction) of the top plate (220). In other words, the top plate (220) may have an N-row, 1-column structure. As will be described in detail later, the configuration in which venting holes (221) are provided at predetermined intervals in the width direction of the top plate (220) is intended to prevent gas from spreading to other battery cells (110) inside the module case (200) when gas is generated in any battery cell (110) inside the module case (200), and to induce discharge in the upper direction of the module case (200) via the shortest path.

[0049] Referring again to FIGS. 2 to 4, the venting channel forming sheet (300) may be placed on the lower surface of the top plate (220) facing the cell stack (100). The venting channel forming sheet (300) may be configured to form a gas passage on the upper surface of the top plate (220) when a thermal event occurs in the battery module (10).

[0050] The above-described venting channel forming sheet (300) may be provided with a folding portion (310) that is folded one or more times at a position corresponding to the venting hole (221) and at least a portion of which is coupled to the top plate (220). The folding portion (310) may be configured to be unfolded over the venting hole (221) by a predetermined pressure to form a gas passage on the upper part of the top plate (220). For example, the folding portion (310) located at a position corresponding vertically to the battery cell (110) where thermal runaway has occurred may be unfolded by the pressure of the venting gas generated from the battery cell (110) and rise up over the venting hole (221) to form a predetermined gas passage. The gas passage formed at this time may be a tunnel type with the front and rear open so that the venting gas can be directed toward the front-rear direction (Y-direction) of the battery module (10).

[0051] The above-mentioned venting channel forming sheet (300) may be made of a material having electrical insulation and fire resistance. For example, the above-mentioned venting channel forming sheet (300) may be made of a material with excellent electrical insulation and flame resistance, such as graphite or silicon. This venting channel forming sheet (300) can normally serve to electrically insulate the battery cells (110) and the top plate (220).

[0052] Specifically, the venting channel forming sheet (300) may include a plurality of unit venting channel forming sheets (300A, 300B, 300C). For example, as in the embodiment of FIG. 2, the venting holes (221) arranged in 6 rows and 3 columns on the top plate (220) may be covered by three unit venting channel forming sheets (300A, 300B, 300C). That is, in FIG. 2, the six venting holes (221) in the first column may be covered by the first unit venting channel forming sheet (300A), the six venting holes (221) in the second column may be covered by the second unit venting channel forming sheet (300B), and the six venting holes (221) in the third column may be covered by the third unit venting channel forming sheet (300C).

[0053] The above-mentioned venting channel forming sheet (300) may have folding portions (310) that correspond one-to-one with N venting holes (221). For example, the above-mentioned venting channel forming sheet (300) may have 18 folding portions (310) that correspond one-to-one with a total of 18 venting holes (221) of the top plate (220) shown in FIG. 2.

[0054] Referring to FIG. 5, the venting channel forming sheet (300) may include a first fixing part (320) and a second fixing part (330) that are fixed to the lower surface of the top plate (220) with the folding part (310) in between.

[0055] The first fixing part (320) and the second fixing part (330) may be configured to be fixed to the lower surface of the top plate (220) by adhesive or bolting. However, as long as the first fixing part (320) and the second fixing part (330) can be fixed to the lower surface of the top plate (220) by an attachment method, it is not necessary to use an adhesive or bolting method.

[0056] When the first fixing part (320) and the second fixing part (330) are fixed, when gas pressure acts on the venting channel forming sheet (300) during a thermal event, the first fixing part (320) and the second fixing part (330) do not move, and only the folding part (310) unfolds and can protrude to the upper part of the top plate (220) through the venting hole (221). At this time, a tunnel-shaped gas passage having a circumference corresponding to the folded length of the folding part (310) can be formed on the upper part of the top plate (220).

[0057] For reference, the venting channel forming sheet (300) according to the present embodiment has a plurality of venting holes (221) and a plurality of corresponding folding parts (310) in the width direction (X direction) of the top plate (220), and two adjacent folding parts (310) share a fixing part. The first fixing part (320) and the second fixing part (330) are fixed parts located on the left and right sides based on one folding part (310). That is, the second fixing part (330) located on the right side of a certain folding part (310) may correspond to the first fixing part (320) with respect to another folding part (310) adjacent to the right side of the certain folding part (310).

[0058] FIG. 6 is a drawing illustrating an example in which the folding part (310A) is unfolded during thermal runaway of the battery cell (110) in the outermost region of the battery module (10) of FIG. 4, FIG. 7 is a perspective view of the battery module (10) having a gas passage formed corresponding to FIG. 6, FIG. 8 is a drawing illustrating an example in which the folding parts (310A, 310D) corresponding to the battery cell (110) in the outermost region and the battery cell (110) in the central region, respectively, are unfolded during thermal runaway of the battery cell (110) in the outermost region of FIG. 4, FIG. 9 is a perspective view of the battery module (10) having a gas passage formed corresponding to FIG. 8.

[0059] Referring to FIGS. 6 to 9 above, an example of gas discharge and the formation of a directional venting channel when a thermal event occurs in a battery module (10) according to one embodiment of the present invention will be briefly described.

[0060] As shown in FIG. 6, the battery module (10) according to the present embodiment may have battery cells (110) divided into a predetermined number by a barrier member (120) and venting holes (221) provided in the upper region of the divided battery cells (110). For example, when a thermal event occurs in the battery cell (110) in the outermost right region among the battery cells (110), the folding part (310A) that was folded is unfolded and rises above the venting hole (221) due to the pressure of the discharge (piece detached from the current collector or electrode active material, etc.) or venting gas near the battery cell (110) where the thermal event occurred. Then, a gas passage may be formed on the upper part of the top plate (220) as in FIG. 7. At this time, the gas passage may be in the form of a tunnel with the front and rear open.

[0061] According to this configuration, the discharge or venting gas ejected from the battery cell (110) in the outermost region can be discharged to the top of the top plate (220) through the open venting hole (221) and guided along the gas passage in the front-rear direction (Y-direction) of the battery module (10). At this time, since the movement of heat in the lateral direction of the top plate (220) is restricted, thermal damage to other battery cells (110) can be minimized. Additionally, as the internal pressure of the module case (200) is relieved, the folding parts (310) adjacent to other battery cells (110) where no thermal event occurred can remain in a folded state. That is, as shown in Fig. 7, the remaining venting holes (221), excluding the venting hole (221) located at the outermost edge, are kept covered by the corresponding folding parts (310B~310F), so that the discharge or venting gas does not flow from the outside to the inside of the top plate (220).

[0062] As another example, as illustrated in FIG. 8, when a thermal event occurs in the battery cell (110) in the outermost right region and the battery cell (110) in the central region among the battery cells (110), the folding portions (310A, 310D) corresponding to the battery cells (110) are unfolded, so that an isolated gas passage can be formed on the upper part of the top plate (220) as shown in FIG. 9.

[0063] According to the above configuration, the discharge and venting gas generated from the battery cells (110) where a thermal event occurred are discharged directly from the inside of the module case (200) upward to the outside of the module case (200) and do not spread to other battery cells (110). In addition, the remaining venting holes (221), excluding the venting hole (221) located at the outermost edge and the venting hole (221) located in the central area, are kept covered by the corresponding folding parts (310B, 310C, 310E, 310F), so that the discharge and venting gas do not flow back into the inside of the module case (200).

[0064] In addition, the discharge and venting gas can be induced to flow in the forward and backward directions of the battery module (10) along the gas passage outside the module case (200). As such, when a thermal event occurs, the flow of the discharge and venting gas can be controlled in an intended direction, thereby minimizing thermal damage to other battery modules (10) arranged in the lateral direction (X-direction) of the battery pack.

[0065] FIG. 10 is a partial cross-sectional view of a battery module (10) according to another embodiment of the present invention, FIG. 11 is a drawing showing the folding part (310) of FIG. 10 in an unfolded state, FIG. 12 is a partial cross-sectional view of a battery module (10) according to yet another embodiment of the present invention, and FIG. 13 is a drawing showing the folding part (310) of FIG. 12 in an unfolded state.

[0066] Reference numbers identical to those in previous drawings indicate identical components. Duplicate descriptions of identical components will be omitted, and the explanation will focus on the differences from the previously described embodiments.

[0067] The embodiment of the present invention illustrated in FIGS. 10 to 13 differs from the previously described embodiment in the combined structure of the top plate (220) and the venting channel forming sheet (300).

[0068] First, a battery module (10) according to another embodiment of the present invention may include, as shown in FIG. 10, a first sheet fixing member (223) that protrudes downward from the top plate (220) and is connected to the first fixing member (320), and a second sheet fixing member (224) that is connected to the second fixing member (330). The first sheet fixing member (223) and the second sheet fixing member (224) have the same structure, and the first sheet fixing member (223) may include a body (225) that penetrates the first fixing member (320) and a support member (226) formed at the bottom of the body (225) to support the lower surface of the first fixing member (320).

[0069] The first sheet fixing member (223) and the second sheet fixing member (224) may be means capable of mechanically fixing the first fixing part (320) and the second fixing part (330) to the top plate (220), such as rivets. According to the first sheet fixing member (223) and the second sheet fixing member (224), the fixing force may be further increased compared to when the first fixing part (320) and the second fixing part (330) are attached to the top plate (220).

[0070] According to the configuration of this embodiment, compared to the above-described embodiment, even if the folding part (310) is strongly unfolded by the pressure of gas as shown in FIG. 11, there is less risk of the first fixing part (320) and the second fixing part (330) falling off the top plate (220), so the gas passage can be maintained more stably.

[0071] In a battery module (10) according to another embodiment of the present invention, as shown in FIG. 12, the first sheet fixing member (223A) and the second sheet fixing member (224) have the same structure and can be configured to be positioned vertically aligned with the barrier member (120), respectively. The body (225A) can be provided in a form that protrudes downward from the top plate (220) compared to the previously described embodiment so that the barrier member (120) and the support member (226) come into contact. In particular, compared to the embodiment of FIG. 10, according to the embodiment of FIG. 12, the vertical upper part of the battery member can be configured so that the left and right sides are blocked by the first sheet fixing member (223A) or the second sheet fixing member (224).

[0072] Accordingly, according to another embodiment of the present invention, the discharge and venting gas of the battery cell (110) in which thermal runaway has occurred can be guided more intensively toward the upper venting hole (221) and discharged to the outside. In addition, the heat and gas of the thermally runaway battery cell (110) are difficult to propagate beyond the barrier member (120) and the first and second sheet fixing members (224) to other adjacent battery cells (110).

[0073] FIG. 14 is a perspective view of another battery module (10) of the present invention, and FIG. 15 is a perspective view of the battery module (10A) of FIG. 14 with the flame-retardant cover (500) removed.

[0074] Referring to FIGS. 14 and 15, a battery module (10A) according to another embodiment of the present invention may further include a flame-retardant cover (500) compared to the battery module (10) of the above-described embodiment.

[0075] The flame-retardant cover (500) may be configured to prevent venting gas or flames emitted when a thermal event occurs within the battery module (10A) from being transferred to another battery module (10). To this end, the flame-retardant cover (500) may be provided with a material having excellent heat resistance and / or fire resistance, such as a mica sheet or a silicone composite material.

[0076] Since this flame-retardant cover (500) does not deform even when high-temperature heat is generated and maintains structural stability, it can stably block high-temperature gas or flames generated in the battery cell (110).

[0077] The flame-retardant cover (500) may be provided with an opening / closing part (510) configured to rupture or at least partially separate when a pressure greater than the allowable pressure is applied to an area corresponding to the venting hole (221) of the top plate (220), as shown in the embodiment illustrated in FIGS. 14 and 15.

[0078] To this end, the opening / closing part (510) may be formed in a shape that creates a notch line or a shredding line (511). The opening / closing part (510) may be ruptured or at least partially separated by the pressure when the folding part (310) is unfolded.

[0079] A battery module (10) according to another embodiment of the present invention has a structure in which, starting from the top layer, the opening / closing part (510) of the flame-retardant cover (500), the venting hole (221) of the top plate (220), the folding part (310) of the venting channel forming sheet (300), and the battery cell (110) are arranged in order.

[0080] Accordingly, according to the above embodiment of the present invention, when a thermal event occurs in a specific battery cell (110), the folding part (310) located on the upper part of the specific battery cell (110) is unfolded by the pressure of the discharge and gas and rises above the venting hole (221), and at this time, the opening / closing part (510) may rupture or at least part of it may be separated by the pressure. Then, as described above, a gas passage through which the discharge and venting gas can move in the forward and backward directions of the battery module (10) can be provided on the flame-retardant cover (500).

[0081] At this time, the flame-retardant cover (500) can more effectively block discharges or venting gases emitted to the outside of the module case (200) from flowing back into the interior of the module case (200). Therefore, according to the battery module (10A) of the present invention including the flame-retardant cover (500), heat propagation to adjacent battery cells (110) or other neighboring battery modules (10A) can be minimized, thereby preventing or delaying thermal runaway propagation more effectively.

[0082] FIG. 16 is a schematic perspective view of a battery pack (20) including a battery module (10) according to one embodiment of the present invention.

[0083] Referring to FIG. 16, a battery pack (20) according to one embodiment of the present invention may include one or more battery modules (10) according to one embodiment of the present invention as described above. The battery pack (20) according to the present invention may further include a pack case for accommodating components such as a Battery Management System (BMS) for integrated control of charging and discharging of one or more battery modules (10), a current sensor, a fuse, etc., as described above.

[0084] The above-described pack case may include a pack tray (21) capable of compartmentalizing and storing battery modules (10), a pack lid (22) coupled to the pack tray (21) and covering the upper portion of the battery modules (10), and at least one gas outlet (23). The gas outlet (23) may preferably be provided on one side wall of the pack case located at the front or rear of the aforementioned battery module (10).

[0085] FIG. 17 is a schematic perspective view of a vehicle including a battery pack (20) according to one embodiment of the present invention.

[0086] Referring to FIG. 17, a vehicle according to one embodiment of the present invention may include one or more battery packs (20) or battery modules (10) according to one embodiment of the present invention. The vehicle (1) according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle includes four-wheeled vehicles and two-wheeled vehicles. The vehicle operates by receiving power from the battery pack or battery module (10) according to one embodiment of the present invention.

[0087] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0088] Meanwhile, where terms indicating directions such as up, down, left, right, front, and back are used in this specification, these terms are used merely for convenience of explanation and may vary depending on the location of the object or the position of the observer, as is obvious to those skilled in the art of this invention. Explanation of the symbols

[0089] 10: Battery module 100: Cell stack 110: Battery cell 111: Electrode lead 200: Module Case 210: Case Body 211: Bottom plate 212, 213: Side plate 220: Top plate 221: Venting hole 230, 240: End cover 300: Venting channel forming sheet 310: Folding part 320: First fixing part 330: Second fixed part 400: Busbar frame assembly 410: Busbar frame 420: Busbar 500: Flame-retardant cover 510: Opening / closing part

Claims

Claim 1 A battery module comprising: a cell stack having a plurality of battery cells; a module case having a venting hole in a top plate provided to accommodate the cell stack and covering the upper portion of the cell stack; and a venting channel forming sheet coupled to the top plate and having a folding portion folded one or more times at a position corresponding to the venting hole, wherein the folding portion is provided to unfold over the venting hole by a predetermined pressure to form a gas passage on the upper portion of the top plate, and the venting channel forming sheet includes a first fixing portion and a second fixing portion fixed to the lower surface of the top plate with the folding portion in between. Claim 2 A battery module according to claim 1, wherein the venting channel forming sheet is disposed on the lower surface of the top plate facing the cell stack. Claim 3 A battery module according to claim 1, wherein the venting channel forming sheet is made of a material having electrical insulation and fire resistance. Claim 4 delete Claim 5 A battery module according to claim 1, characterized in that the first fixing part and the second fixing part are bonded or bolted to the lower surface of the top plate. Claim 6 A battery module according to claim 1, characterized by comprising: a first sheet fixing member that protrudes downward from the top plate and is connected to the first fixing part; and a second sheet fixing member connected to the second fixing part. Claim 7 A battery module according to claim 6, wherein the first sheet fixing member and the second sheet fixing member have the same structure, and the first sheet fixing member includes a body penetrating the first fixing member and a support member formed at the bottom of the body to support the lower surface of the first fixing member. Claim 8 A battery module according to claim 1, wherein the top plate comprises N venting holes spaced apart along the stacking direction of the battery cells. Claim 9 A battery module according to claim 8, wherein the venting channel forming sheet comprises a folding portion having a one-to-one correspondence with N venting holes. Claim 10 A battery module according to claim 1, further comprising a flame-retardant cover coupled to the upper part of the module case, wherein the flame-retardant cover has an opening / closing portion configured to rupture or at least partially separate by a predetermined pressure or heat in an area corresponding to the venting hole of the top plate. Claim 11 A battery module according to claim 10, wherein the opening and closing part is provided in a form formed by making a notch line or a shredding line in the flame-retardant cover. Claim 12 A battery module according to claim 1, wherein the module case comprises: a case body open at least on the upper surface; and a top plate that covers the upper surface of the case body and is coupled to the case body. Claim 13 A battery module according to claim 1, wherein the battery cells are pouch-type battery cells, and the pouch-type battery cells are stacked in one direction. Claim 14 A battery pack comprising a battery module according to any one of paragraphs 1 through 3 and paragraphs 5 through 13. Claim 15 An automobile characterized by including a battery pack according to Clause 14.

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