Battery module

Abstract

The present invention relates to a battery module designed to minimize thermal propagation to adjacent battery cells when high-temperature gas is generated in a battery cell housed within the module, and to discharge said generated gas to the top of the battery module. The battery module comprises: a cell stack including a plurality of battery cells arranged so that one or both sides are in close contact or adjacent to each other; a module frame that houses the cell stack while wrapping the top, bottom, and sides of the cell stack; and a cover plate that is coupled to the module frame to cover the front and rear of the cell stack. The battery cell comprises an electrode assembly, an electrode lead connected to the electrode assembly, and a battery case that houses the electrode assembly by allowing the electrode lead to be drawn out to the outside and has a bonded edge, and includes a venting portion indented toward the electrode assembly on one side of the edge of the battery case, and the module frame includes an open hole that is opened corresponding to the location where the venting portion of the cell stack is formed.

Description

Technology Field

[0001] The present invention relates to a battery module designed to minimize thermal propagation to adjacent battery cells when high-temperature gas is generated in a battery cell housed within the module, and to allow the generated gas to be discharged to the top of the battery module. Background Technology

[0003] The use of lithium-ion batteries has recently been increasing due to their excellent electrical characteristics and the advantage of being relatively lightweight.

[0004] Generally, lithium secondary batteries are classified into battery cells containing electrode assemblies in which multiple positive electrodes, negative electrodes, and separators are stacked, battery modules in which multiple battery cells are arranged, and battery packs in which multiple battery modules are contained.

[0005] The above battery cells can be classified into pouch type, prismatic type, and cylindrical type depending on their shape and structure.

[0006] FIG. 1 illustrates a pouch-type battery cell with electrode leads protruding from both sides. The pouch-type battery cell has a sealed shape in which a battery case covers the upper and lower parts of an electrode assembly. At this time, the battery case is folded to wrap around the electrode assembly on one side of the electrode assembly, and the edges are sealed on the other side of the electrode assembly to seal the internal electrode assembly.

[0007] Subsequently, the above battery cells are arranged in multiple numbers as shown in FIG. 2(a) to form a single cell stack, and the surface is covered with a module frame and an end plate to produce a battery module as shown in FIG. 2(b).

[0008] Meanwhile, high-temperature gas may be generated in the battery cell unit due to abnormal reactions under abnormal conditions, and pouch-type battery cells such as Fig. 1 have a problem in that the release of gas to the outside is delayed due to the unique sealing structure, which causes a larger explosion.

[0009] In order to solve the above problem, conventionally, a weak point was intentionally formed in the battery case of the battery cell, and the gas was released through the weak point when gas was generated.

[0010] However, while the explosion of the battery cell itself could be prevented through the above-mentioned measures, there were limitations in solving the problem at the battery module level. For example, if high-temperature gas is released from a single battery cell housed inside a battery module as shown in Fig. 2(b), thermal propagation easily proceeds to other battery cells due to the structural limitation that each battery cell shares a single space. This caused large explosions and fires at the battery module level.

[0011] Therefore, there is a need to design the structure of battery cells and battery modules so that high-temperature gases generated internally can be effectively and stably released to the outside, not only at the battery cell level but also at the battery module level. Prior art literature

[0013] Korean Registered Patent No. 10-1294259 The problem to be solved

[0014] Accordingly, the present invention aims to provide a battery cell that prevents the explosion of the battery cell and enables the rapid release of gas when high-temperature gas is generated in the battery cell.

[0015] In addition, the present invention aims to provide a battery module having a structure in which thermal propagation does not proceed to other battery cells when high-temperature gas is emitted from any one of the plurality of battery cells accommodated in the battery module.

[0016] Other objects and advantages of the present invention may be understood from the following description and will become more clearly apparent from the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims. means of solving the problem

[0018] According to the present invention, a battery module is provided comprising: a cell stack including a plurality of battery cells arranged such that one or both sides are in close contact or adjacent to each other; a module frame that encloses the upper, lower, and side portions of the cell stack and accommodates the cell stack; and a cover plate that is coupled to the module frame to cover the front and rear portions of the cell stack; wherein the battery cell comprises an electrode assembly, an electrode lead connected to the electrode assembly, and a battery case having a rim that accommodates the electrode assembly by allowing the electrode lead to be drawn out to the outside, and includes a venting portion indented toward the electrode assembly on one side of the rim of the battery case, and the module frame includes an open hole that is opened corresponding to the location where the venting portion of the cell stack is formed.

[0019] The cell stack can be accommodated in the module frame by being positioned so that the venting portion faces upward.

[0020] The battery case of each battery cell included in the above cell stack may include a venting portion at the same location.

[0021] The above-mentioned open hole may be formed to extend along the width direction of the module frame.

[0022] At least two venting portions may be continuously formed on one side of the battery case at a predetermined interval.

[0023] The above-mentioned open holes may be formed at predetermined intervals along the longitudinal direction of the module frame.

[0024] The module frame may include a separator pin that extends from the top of the cell stack toward the cell stack and extends along the length direction of the module frame.

[0025] The module frame comprises a U-shaped lower plate that wraps around the lower and side portions of the cell stack; and an upper plate that covers the upper portion of the cell stack; and the open hole may be formed in the upper plate.

[0026] The upper plate may include a separating pin formed extending along the longitudinal direction of the module frame at its lower portion.

[0027] At least two of the above separator pins are formed on the lower part of the upper plate, and the spacing of the separator pins may be equal to the thickness of the battery cell or greater than the thickness of the battery cell.

[0028] The above separator pin can be inserted between the battery cells to separate the space between the battery cells and the upper plate along the width direction of the module frame.

[0029] Both ends of the above separation pin are each connected to a cover plate, and the lower end can be connected to a lower plate.

[0030] The lower plate includes guide grooves on both sides into which both ends of the upper plate can be inserted, and the guide grooves may be formed to extend along the longitudinal direction of the module frame so that the upper plate can slide.

[0031] The above module frame includes an integrated monoplate that encloses the upper, lower, and side portions of the cell stack, and the monoplate is composed of an upper cover portion corresponding to the upper portion of the cell stack, a lower cover portion corresponding to the lower portion of the cell stack, and a side cover portion corresponding to the side portion of the cell stack, and the opening hole may be formed in the upper cover portion of the monoplate.

[0032] The upper cover portion of the above monoplate may include a separation pin formed extending along the longitudinal direction of the module frame at the bottom. Effects of the invention

[0034] According to the present invention, when high-temperature gas is generated in a battery cell, the gas is released in an intentional direction to prevent the explosion of the battery cell.

[0035] In addition, according to the present invention, even if high-temperature gas is generated in one battery cell, heat transfer to other battery cells is prevented, thereby having the effect of preventing explosions or fires from occurring in the battery module unit. Brief explanation of the drawing

[0037] Figure 1 shows a conventional pouch-type battery cell. FIG. 2 is a perspective view of a conventional battery module. FIG. 3 is a perspective view of a battery module according to a first embodiment of the present invention. Figure 4 shows a battery cell of the present invention. Figure 5 shows a modified example of the battery cell of the present invention. FIG. 6 is a cross-sectional view of a battery module according to a first embodiment of the present invention. FIG. 7 shows an upper plate of a battery module according to a second embodiment of the present invention. FIG. 8 is a cross-sectional view of a battery module according to a second embodiment of the present invention. FIG. 9 is a perspective view of a battery module according to a second embodiment of the present invention. FIG. 10 is a perspective view of a battery module according to a third embodiment of the present invention. Specific details for implementing the invention

[0038] 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, and 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.

[0039] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0040] 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.

[0041] 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.

[0043] FIGS. 3 to 6 relate to a battery module (1000) of the present invention according to a first embodiment, FIGS. 7 to 9 relate to a battery module (1000) of the present invention according to a second embodiment, and FIG. 10 relates to a battery module (1000) of the present invention according to a third embodiment.

[0044] Hereinafter, each embodiment of the battery module (1000) of the present invention will be described with reference to each of the drawings above.

[0046] (First embodiment)

[0047] FIG. 3 is a perspective view of a battery module (1000) according to a first embodiment of the present invention.

[0048] As illustrated in FIG. 3 above, the battery module (1000) of the present invention includes a cell stack (100), a module frame (200), and a cover plate (300).

[0049] The cell stack (100) is composed of a plurality of battery cells (110). More specifically, the cell stack (100) includes a plurality of battery cells (110) arranged so that one or both sides are in close contact or adjacent to each other.

[0051] The above battery cell (110) is composed of an electrode assembly (111), an electrode lead (112), and a battery case (113).

[0052] The electrode assembly (111) comprises a plurality of stacked unit cells, and each unit cell is composed of an anode, a cathode, and a separator interposed between the anode and the cathode.

[0053] The above electrode lead (112) includes a negative lead electrically connected to the negative electrode of each unit cell and a positive lead electrically connected to the positive electrode of each unit cell.

[0054] The battery case (113) is basically made of a metal material such as aluminum and is used to seal the electrode assembly (111).

[0055] The battery case (113) accommodates the electrode assembly (111) and seals the electrode assembly (111) by joining the edges.

[0056] FIG. 4 shows a battery cell (110) of the present invention. Referring to FIG. 4, the battery case (113) covers the electrode assembly (111) (not shown) by allowing the electrode lead (112) to be drawn out to the outside, and seals the electrode assembly (111) by joining the edges.

[0057] The joint portion (115) of the above-mentioned edge can be primarily joined using an adhesive or the like, and can be secondarily joined using heat.

[0058] The battery cell (110) of the present invention is characterized by including a venting portion (v) that is recessed toward the electrode assembly (111) on one side of the edge of the battery case (113).

[0059] The above venting portion (v) is formed by notching the joint portion (115) of the battery case (113), and the joint area of ​​the notched portion is smaller than the joint area of ​​the unnotched portion. Therefore, the strength of the venting portion (v) among the joint portions (115) of the battery case (113) is the weakest, and the venting portion (v) can be damaged relatively easily by external pressure compared to other parts.

[0060] In the battery cell (110) of the present invention, when high-temperature gas is generated inside, the venting part (v) is torn, thereby allowing the gas to be released to the outside through the venting part (v).

[0061] As shown in FIG. 4, the venting portions (v) may be formed in multiple numbers along the joint portion (115) of the battery case (113). That is, at least two venting portions (v) are formed continuously at a predetermined distance apart on one side of the battery case (113). At this time, since the multiple venting portions (v) are formed in the same direction from the battery cell (110), the gas generated inside the battery cell (110) and released to each venting portion (v) is also released only in the same direction.

[0062] FIG. 5 shows a modified example of the battery cell (110) of the present invention.

[0063] The above battery case (113) can be accommodated in a battery module (1000) by folding the joint portion (115) of the edge inward, and a tape (114) can be attached to the area excluding the venting portion (v) as shown in FIG. 5 to maintain the folded state of the joint portion (115).

[0065] It is preferable that each battery cell (110) included in the cell stack (100) be arranged so that the venting portion (v) faces in the same direction.

[0066] In addition, it is preferable that the venting portion (v) of each battery cell (110) be formed at the same location in the joint portion (115) of the battery case (113).

[0068] The module frame (200) accommodates the cell stack (100) by wrapping the upper, lower, and side portions of the cell stack (100). At this time, the cell stack (100) is accommodated in the module frame (200) with the venting portion (v) facing upward, as shown in FIG. 3. Therefore, when high-temperature gas is generated in the battery cell (110) included in the cell stack (100), the gas tears through the venting portion (v) of the battery cell (110) and is released upward from the cell stack (100).

[0069] The battery module (1000) of the present invention is characterized by including an open hole (h) that is opened corresponding to the location where the venting portion (v) of the cell stack (100) is formed, so that high-temperature gas generated in the cell stack (100) can be released to the outside of the battery module (1000) without being stagnant inside.

[0070] The above-mentioned open hole (h) is formed to extend along the width direction of the module frame (200) in correspondence with the venting portion (v) of the cell stack (100).

[0071] In addition, the above-mentioned open hole (h) is formed at a predetermined interval along the length direction of the module frame (200) to correspond to the venting portion (v) formed at a predetermined interval along the length direction of the cell stack (100).

[0072] The module frame (200) includes a U-shaped lower plate (210) that wraps around the lower and side portions of the cell stack (100), and an upper plate (220) that covers the upper portion of the cell stack (100).

[0073] The lower plate (210) supports the lower part of the cell stack (100) and supports and wraps the side of the battery cell (110) located at the outermost edge of the cell stack (100).

[0074] The upper plate (220) is combined with the lower plate (210) to cover the upper part of the cell stack (100).

[0075] The above-mentioned open hole (h) is preferably formed in an upper plate (220) located on the upper part of the cell stack (100).

[0076] FIG. 6 is a cross-sectional view of a battery module (1000) according to a first embodiment of the present invention.

[0077] As shown in FIG. 6 above, the opening hole (h) of the upper plate (220) is formed corresponding to the position of the venting portion (v) of the battery cell (110) included in the cell stack (100). Accordingly, when high-temperature gas is generated in one battery cell (110) and released through the venting portion (v), the gas escaping from the venting portion (v) is not transferred to another battery cell (110) but is released to the outside of the battery module (1000) through the opening hole (h) of the upper plate (220).

[0079] The above cover plate (300) is combined with the module frame (200) to cover the entire front and rear of the cell stack (100) as shown in FIG. 3.

[0080] A busbar frame (not shown) including a terminal electrically connected to the electrode lead (112) of each battery cell (110) included in the cell stack (100) may be further inserted between the cover plate (300) and the cell stack (100), and the cover plate (300) serves to protect the cell stack (100) and the busbar frame.

[0082] (Second embodiment)

[0083] The upper plate (220) of the battery module (1000) according to the second embodiment of the present invention may further include a separator pin (p) that extends from the opening hole (h) to the upper part of the battery cell (110) and guides the gas so that the gas released through the venting part (v) of the battery cell (110) can be released to the outside through the opening hole (h).

[0084] The above separator pin (p) is used for the purpose of preventing gas from escaping into the gap between the battery cells (110) and the battery cells (110) or the space between the battery cells (110) and the upper plate (220) and transferring heat to other battery cells (110).

[0085] FIG. 7 shows a perspective view, a front view, and a side view of an upper plate (220) of a battery module (1000) according to a second embodiment of the present invention.

[0086] As illustrated in FIG. 7 above, the lower part of the upper plate (220) includes a separator pin (p) that extends downward and is formed along the longitudinal direction of the module frame (200). More specifically, the separator pin (p) is formed so that both ends are connected to cover plates (300) located on both sides of the battery module (1000). Thus, the separator pin (p) separates the space between one cell stack (100) and the upper plate (220) into units of battery cells (110), thereby causing one battery cell (110) to be disconnected from another battery cell (110).

[0087] At least two of the above separation pins (p) are formed on the lower part of the upper plate (220), and as shown in FIG. 7, they are formed spaced apart at a predetermined interval with respect to the width direction of the upper plate (220).

[0088] FIG. 8 is a cross-sectional view of a battery module (1000) according to a second embodiment of the present invention.

[0089] The above separation pin (p) is inserted between a plurality of battery cells (110) arranged to be in close contact or adjacent to each other when the upper plate (220) is combined with the lower plate (210), thereby separating and disconnecting the upper space of adjacent battery cells (110) along the width direction of the module frame (200).

[0090] It is preferable that the spacing of the separator pins (p) be equal to the thickness of the battery cell (110) or greater than the thickness of the battery cell (110), as shown in FIG. 8. That is, if the spacing of the separator pins (p) is equal to the thickness of the battery cell (110), one battery cell (110) may be located between adjacent separator pins (p), and if the spacing of the separator pins (p) is greater than the thickness of the battery cell (110), at least two battery cells (110) may be located between adjacent separator pins (p). (However, for ease of understanding, only an example in which the spacing between the separator pins (p) is equal to the thickness of the battery cell (110) is illustrated in the drawings of the present invention.)

[0091] Although not shown, the separator pin (p) may be extended downward and combined with the lower plate (210). In this case, the separator pin (p) can not only divide the space between the cell stack (100) and the upper plate (220), but also separate and cut off the space within the battery module (1000) along the width direction of the module frame (200).

[0092] FIG. 9 is a perspective view of a battery module (1000) according to a second embodiment of the present invention.

[0093] Referring to FIG. 9 above, the open hole (h) formed in the upper plate (220) is separated along the width direction of the module frame (200) by the separation pin (p).

[0094] Due to the structure of the separator pin (p) as shown in Fig. 9 above, the high-temperature gas generated in one battery cell (110) does not seep into an adjacent battery cell (110), but moves to an open hole (h) by a pair of separator pins (p) that cut off the upper space on both sides of the battery cell (110) and is discharged to the top of the battery module (1000).

[0095] Accordingly, the battery module (1000) according to the second embodiment can effectively discharge high-temperature gas generated in the battery cell (110) unit through the open hole (h) of the module frame (200) formed corresponding to the venting portion (v) of the battery cell (110). In addition, it is possible to quickly guide the high-temperature gas generated in one battery cell (110) to the open hole (h) and discharge it to the outside through the separator pin (p) without transferring it to other battery cells (110).

[0097] The upper plate (220) may be screw-coupled to the lower plate (210) via a bolt (not shown) while covering the upper part of the cell stack (100), or may be coupled to the lower plate (210) in a sliding manner.

[0098] Specifically, a guide groove (not shown) into which both ends of the upper plate (220) can be inserted may be formed on the upper portion of the inner sides facing each other on the lower plate (210). In this case, the guide groove is extended along the longitudinal direction of the module frame (200) so that the upper plate (220) slides, and the upper plate (220) is slidably inserted into the lower plate (210) along the guide groove and coupled.

[0100] (Third embodiment)

[0101] FIG. 10 is an exploded view of a battery module (1000) according to a third embodiment of the present invention.

[0102] As illustrated in FIG. 10 above, the module frame (200) of the battery module (1000) according to the third embodiment of the present invention includes an integrated monoplate (230) that wraps the upper, lower, and side portions of the cell stack (100).

[0103] The mono plate (230) is composed of an upper cover portion (231) corresponding to the upper part of the cell stack (100), a lower cover portion (233) corresponding to the lower part of the cell stack (100), and a side cover portion (232) corresponding to the side of the cell stack (100).

[0104] In the battery module (1000) according to the third embodiment, an open hole (h) is formed in the upper cover portion (231) of the mono plate (230).

[0105] The mono plate (230) includes a separation pin (p) formed extending along the longitudinal direction of the module frame (200) at the lower part of the upper cover portion (231) as shown in FIG. 10.

[0106] The cell stack (100) is slidably inserted into the monoplate (230), and the separator pin (p) is interposed between the battery cells (110) included in the cell stack (100) inserted into the monoplate (230) to separate the upper space of each battery cell (110).

[0108] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application. Explanation of the symbols

[0109] 1: (Conventional) battery cell 1a: (Conventional) electrode lead 1b: (Conventional) battery case 2: (Conventional) Cell Stack 3,4: (Conventional) Module Frame 5: (Conventional) End Plate 10: (Conventional) Battery Module 1000: Battery module 100: Cell stack 110: Battery cell 111: Electrode assembly 112: Electrode Lead 113: Battery Case 114: Tape 115: Joint 200: Module Frame 210: Lower plate 220: Upper plate 230: Mono Plate 231: Upper cover part 232: Side cover 233: Lower cover part 300: Cover plate v: Venting section h: Open hole p: Separator pin

Claims

Claim 1 A battery module comprising: a cell stack including a plurality of battery cells arranged such that one or both sides are in close contact or adjacent to each other; a module frame that encloses the upper, lower, and side portions of the cell stack and accommodates the cell stack; and a cover plate coupled to the module frame to cover the front and rear portions of the cell stack; wherein the battery cell includes an electrode assembly, an electrode lead connected to the electrode assembly, and a battery case having a rim joined thereto that accommodates the electrode assembly by allowing the electrode lead to be drawn out to the outside, wherein the battery cell includes a venting portion indented toward the electrode assembly on one side of the rim of the battery case, and the module frame includes an opening hole that is opened corresponding to the location where the venting portion of the cell stack is formed, wherein the venting portion is formed continuously in a plurality at a predetermined interval along the length direction of the cell stack, and the opening hole is formed extending along the width direction of the module frame and is formed in a plurality at a predetermined interval along the length direction of the module frame. Claim 2 In claim 1, the cell stack is a battery module that is accommodated in the module frame and arranged such that the venting portion faces upward. Claim 3 In claim 1, a battery module comprising a venting portion at the same location in the battery case of each battery cell included in the cell stack. Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A battery module according to claim 1, wherein the module frame extends toward the cell stack from the upper part of the cell stack and includes a separator pin formed extending along the longitudinal direction of the module frame. Claim 8 In claim 1, the module frame comprises a U-shaped lower plate that wraps around the lower and side portions of the cell stack; and an upper plate that covers the upper portion of the cell stack; and the battery module in which the opening hole is formed in the upper plate. Claim 9 In claim 8, the battery module wherein the upper plate includes a separator pin formed extending along the longitudinal direction of the module frame at the bottom. Claim 10 In claim 9, the separator pins are formed at least two on the lower part of the upper plate, and the spacing of the separator pins is equal to the thickness of the battery cell or greater than the thickness of the battery cell. Claim 11 In claim 9, the battery module wherein the separator pin is inserted between the battery cells to separate the space between the battery cells and the upper plate along the width direction of the module frame. Claim 12 In claim 9, a battery module in which both ends of the separation pin are each coupled to a cover plate and the lower end is coupled to a lower plate. Claim 13 In claim 9, the lower plate includes guide grooves on both sides into which both ends of the upper plate can be inserted, and the guide grooves are formed to extend along the longitudinal direction of the module frame so that the upper plate can slide. Claim 14 A battery module according to claim 1, wherein the module frame comprises an integral monoplate that encloses the upper, lower, and side portions of the cell stack, and the monoplate comprises an upper cover portion corresponding to the upper portion of the cell stack, a lower cover portion corresponding to the lower portion of the cell stack, and a side cover portion corresponding to the side portion of the cell stack, and the opening hole is formed in the upper cover portion of the monoplate. Claim 15 In claim 14, the upper cover portion of the mono plate comprises a battery module including a separator pin formed extending along the longitudinal direction of the module frame at the bottom.

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