Battery module and battery pack including the same

Abstract

To provide a battery module that has a structure that can effectively prevent high-temperature spark from flowing out to the outside, while allowing the venting gas to be quickly discharged when an internal event occurs.SOLUTION: A battery module according to an embodiment of the present disclosure includes: a cell stack in which a plurality of battery cells are vertically stacked; a module housing including a base plate supporting the cell stack, and a pair of side plates covering both side portions of the cell stack and each including a spark direction changing portion formed by bending an end portion of the side plate in a longitudinal direction toward the cell stack; and a bus bar frame assembly covering an opening portion formed on a side of the module housing in a longitudinal direction, the bus bar frame assembly including a bus bar frame coupled to a side of the cells tack in a longitudinal direction and a bus bar located on the bus bar frame and coupled to an electrode lead of the battery cell.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a battery module, a battery pack including the battery module, and an ESS (Energy Storage System) and a vehicle including such a battery pack. More specifically, the present invention relates to a battery module having a structure capable of preventing fires and explosions by releasing venting gas to the outside when venting occurs in a battery cell while suppressing the outflow of sparks containing high-temperature electrode active material and metal particles to the outside of the battery module, and a battery pack and ESS including the battery module.

[0002] This application claims priority based on Korean Patent Application No. 10-2021-0006196, filed on January 15, 2021, and the entire contents disclosed in the specification and drawings of that application are incorporated herein by reference. [Background technology]

[0003] A battery pack applied to an ESS, an electric vehicle, etc. may be manufactured in a form including a plurality of battery modules using lithium secondary batteries that can achieve high output and high capacity. To satisfy the output characteristics of the battery pack required by the ESS and / or the electric vehicle and achieve high capacity, the number of lithium secondary batteries included in one battery module may be increased, and further the number of battery modules included in one battery pack may be increased.

[0004] However, in the case of a battery pack including such a large number of lithium secondary batteries, if a fire or explosion occurs, the damage caused by the fire or explosion becomes even greater.

[0005] Fires in battery packs are initiated by an abnormal rise in temperature and the generation of internal gas in the lithium secondary battery located inside the battery module. When the temperature of the lithium secondary battery rises abnormally and the internal gas is generated, the internal pressure of the lithium secondary battery rises above a certain level, causing venting in the lithium secondary battery, which in turn releases high-temperature gas to the outside of the lithium secondary battery and high-temperature sparks containing electrode active material and aluminum particles.

[0006] At this time, the venting gas must be quickly discharged to the outside of the battery module to prevent the internal pressure of the battery module from increasing. However, if high-temperature sparks are discharged to the outside of the battery module along with the venting gas, the venting gas, the high-temperature sparks, and oxygen may react to cause a fire.

[0007] Therefore, there is a need to develop a battery module having a structure that can quickly discharge venting gas to the outside of the battery module even if thermal runaway occurs due to an abnormal phenomenon such as a short circuit inside the battery cell, while effectively preventing high-temperature sparks containing electrode active material and aluminum particles from leaking to the outside.

[0008] Furthermore, if a structure such as a bus bar frame applied to prevent short circuits between multiple lithium secondary batteries is damaged by continuous contact with high-temperature gas and sparks, oxygen may easily flow from the outside to the inside of the battery module, which may cause a fire to spread to the inside of the battery module. Furthermore, if the bus bar frame is damaged, electrode leads of adjacent lithium secondary batteries that were kept separated by the bus bar frame may come into contact with each other, which may cause the event to spread.

[0009] Therefore, there is a need to develop a battery module having a structure that can block the inflow of external oxygen even if some structures are damaged by high-temperature gas and sparks, and can prevent short circuits from occurring between adjacent lithium secondary batteries, thereby preventing the spread of the event. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a battery module having a structure that can quickly discharge venting gas when an internal event occurs, while effectively preventing high-temperature sparks from leaking to the outside.

[0011] Another object of the present invention is to provide a battery module having a structure that can prevent external oxygen from easily entering the interior of the battery module even if some structures are damaged by high-temperature gas and sparks, and can prevent short circuits from occurring between adjacent lithium secondary batteries.

[0012] The technical problems to be solved by the present invention are not limited to the above problems, and other problems will be clearly understood by those skilled in the art from the following description of the invention. [Means for solving the problem]

[0013] In order to achieve the above object, according to one aspect of the present invention, a battery module includes: a cell stack formed by stacking a plurality of battery cells one above the other; a module housing including a base plate supporting the cell stack; and a pair of side plates covering both sides of the cell stack and having a spark redirection portion formed by bending one longitudinal end of the side plate toward the cell stack; and a bus bar frame assembly including: a bus bar frame covering an opening formed on one longitudinal side of the module housing and coupled to one longitudinal side of the cell stack; and a bus bar frame assembly including a bus bar disposed on the bus bar frame and coupled to an electrode lead of the battery cell.

[0014] The spark redirector may have a shape in which the side plate is bent twice in a direction perpendicular to an extension direction of the side plate.

[0015] The battery module may further include a fireproof sheet interposed between the bus bar frame assembly and the cell stack.

[0016] The fireproof sheet may be made of mica.

[0017] The fireproof sheet may have a plurality of sheet slits through which electrode leads of the battery cells pass.

[0018] The bus bar frame may include a plurality of frame slits, and the sheet slits may be formed at positions corresponding to the frame slits in a number corresponding to the frame slits.

[0019] The fire protection sheet may include at least one sheet hole.

[0020] The bus bar frame may include at least one frame protrusion, and the frame protrusion may be inserted into the sheet hole to fix the fire protection sheet.

[0021] The module housing may further include a fastening frame connecting the pair of spark redirectors.

[0022] The fastening frame includes at least one fastening protrusion, which can be inserted into the sheet hole to fix the fire protection sheet.

[0023] In order to achieve the above object, a battery pack according to another aspect of the present invention includes the battery module according to the above aspect of the present invention.

[0024] In order to achieve the above object, an ESS according to yet another aspect of the present invention includes the battery pack according to the above aspect of the present invention.

[0025] In order to achieve the above object, a vehicle according to yet another aspect of the present invention includes the battery pack according to the above aspect of the present invention. [Effects of the Invention]

[0026] According to one aspect of the present invention, even if some structures are damaged by high-temperature gas and sparks, venting gas can be quickly discharged while effectively preventing high-temperature sparks from escaping to the outside.

[0027] Furthermore, according to one aspect of the present invention, even if some structures are damaged by high-temperature gas and sparks, external oxygen cannot easily flow into the interior of the battery module, and short circuits can be prevented from occurring between adjacent lithium secondary batteries.

[0028] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical concepts of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a diagram illustrating a battery module according to an embodiment of the present invention. [Figure 2] 2 is a plan view showing the battery module shown in FIG. 1 with a bus bar frame assembly and a fireproof sheet removed. FIG. [Figure 3] FIG. 2 is a partial cross-sectional view of the battery module shown in FIG. [Figure 4] 10 is a diagram showing the bus bar frame assembly and fire protection sheet of the present invention coupled to a module housing. FIG. [Figure 5] FIG. 2 is an exploded perspective view showing a portion of the module housing, the bus bar frame assembly, and the fire protection sheet of the present invention. [Figure 6] 10 is a diagram showing a structure in which a fireproof sheet is directly bonded to a module housing of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed as being limited to their ordinary and dictionary meanings, but should be construed as meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best explain the invention. Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical ideas of the present invention, and therefore various equivalents and modifications that can be substituted therefor may exist at the time of filing this application.

[0031] 1 to 3, a battery module according to an embodiment of the present invention includes a cell stack formed by stacking a plurality of battery cells 100 in a vertical direction (a direction parallel to the Z axis), a module housing 200 that accommodates the cell stack, and a pair of bus bar frame assemblies 300 that cover openings formed on one and the other sides in a longitudinal direction (a direction parallel to the X axis) of the module housing 200. In addition to the above-mentioned components, the battery module may further include a fireproof sheet 400 that is interposed between the bus bar frame assembly 300 and the cell stack and is coupled to the bus bar frame assembly 300.

[0032] A pouch-type battery cell may be applied as the battery cell 100. In this case, the battery cell 100 includes an electrode assembly (not shown), a pouch case 110 that houses the electrode assembly, and a pair of electrode leads 120 that are connected to the electrode assembly and extend to the outside of the pouch case 110. The pair of electrode leads 120 extend in opposite directions along the longitudinal direction of the battery cell 100 (a direction parallel to the X-axis).

[0033] The module housing 200 includes a base plate 210 that supports the cell stack and a pair of side plates 220 that cover both sides of the cell stack. The pair of side plates 220 may include spark redirection portions 220a formed by bending one and the other longitudinal ends of the side plates 220 toward the cell stack.

[0034] The spark redirection portion 220a may have a shape in which, for example, the end portion of the side plate 220 in the longitudinal direction is bent twice in a direction approximately perpendicular to the extension direction of the side plate 220.

[0035] The opening formed on one side of the module housing 200 in the longitudinal direction is formed between a pair of spark redirecting portions 220a provided on each of the pair of side plates 220. The electrode lead 120 of the battery cell 100 may be exposed to the outside of the module housing 200 through the opening formed between the pair of spark redirecting portions 220a.

[0036] The battery module according to one embodiment of the present invention is provided with the spark redirection portion 220a as described above, thereby preventing sparks emitted during venting of the battery cell 100 from being ejected outside the module housing 200 along the longitudinal direction of the module housing 200 (direction parallel to the X-axis).

[0037] That is, when the battery cells 100 are vented, high-temperature sparks ejected from both sides of the width direction (direction parallel to the Y axis) of each battery cell 100 constituting the cell stack move toward one end and the other end of the length direction (direction parallel to the X axis) of the battery module, and then change direction toward the cell stack (see the arrow direction shown in FIG. 2).

[0038] The module housing 200 may further include a fastening frame 230 that connects adjacent pairs of spark redirection units 220a and has an open center. The fastening frame 230 is located between the bus bar frame assembly 300 and the fire protection sheet 400. When the fastening frame 230 is provided, the bus bar frame assembly 300 and the fire protection sheet 400 are in close contact with the fastening frame 230 and can be fastened to each other through the open center of the fastening frame 230.

[0039] Meanwhile, although not shown, the openings provided in the module housing 200 of the present invention are formed on both sides in the longitudinal direction of the module housing 200. Therefore, the pair of spark redirecting portions 220a are also provided on both sides in the longitudinal direction of the module housing 200.

[0040] 1 to 5, the bus bar frame assembly 300 includes a bus bar frame 310 and at least one bus bar 320. The bus bar frame assemblies 300 are provided in pairs, and the pair of bus bar frame assemblies 300 cover openings formed on one side and the other side of the module housing 200 in the longitudinal direction (direction parallel to the X-axis), respectively.

[0041] The bus bar frame 310 covers an opening formed on one side and another side of the module housing 200 in the longitudinal direction, and is coupled to one side and another side of the cell stack in the longitudinal direction (direction parallel to the X-axis).

[0042] The bus bar frame 310 may be made of an electrically insulating resin material and may include a plurality of frame slits 310b through which the electrode leads 120 of the battery cells 100 pass. The bus bar frame 310 may further include at least one frame protrusion 310a protruding toward the fireproof sheet 400 for connection with the fireproof sheet 400.

[0043] The bus bar frame 310 has a shape corresponding to one end and the other end of the module housing 200 in the longitudinal direction, i.e., the spark redirecting portion 220a, and is in close contact with the module housing 200. When the module housing 200 includes the fastening frame 230 as described above, the bus bar frame 310 is in close contact with the spark redirecting portion 220a and the fastening frame 230.

[0044] The bus bar 320 is disposed on the outer surface of the bus bar frame 310 and is coupled to the electrode leads 120 passing through the frame slits 310b, thereby electrically connecting a plurality of battery cells 100. The bus bar 320 may have bus bar slits 320b through which the electrode leads 120 pass. In this case, the bus bar slits 320b and the frame slits 310b are formed at positions corresponding to each other. The electrode leads 120 pass through the frame slits 310b and the bus bar slits 320b in order, and are then bent and coupled onto the bus bar 320.

[0045] 1 to 5, the fireproof sheet 400 is interposed between the bus bar frame assembly 300 and the cell stack and is coupled to the bus bar frame assembly 300. The fireproof sheets 400 are provided on both sides of the module housing 200 in the longitudinal direction.

[0046] The fireproof sheet 400 may be made of a mica material that can withstand high-temperature venting gases and sparks and can withstand fires. The fireproof sheet 400 has a plurality of sheet slits 400b through which the electrode leads 120 pass. The sheet slits 400b are formed at positions corresponding to the frame slits 310b formed in the busbar frame 310 and the busbar slits 320b formed in the busbar 320, and the number of the sheet slits 400b corresponds to the positions corresponding to the frame slits 310b formed in the busbar frame 310 and the busbar slits 320b formed in the busbar 320. Thus, the electrode leads 120 of the battery cell 100 are coupled to the busbar 320 by passing through the sheet slits 400b of the fireproof sheet 400 and the frame slits 310b of the busbar frame 310 in that order.

[0047] The fireproof sheet 400 can maintain its structure even if the resin bus bar frame 310 is damaged by high-temperature venting gas and sparks, thereby allowing the electrode leads 120 inserted into the sheet slits 400b to maintain their positions. The fireproof sheet 400 also allows the high-temperature venting gas to be discharged to the outside through gaps between the sheet slits 400b and the electrode leads 120, while minimizing the release of high-temperature sparks containing active material and aluminum particles to the outside. The fireproof sheet 400 also prevents oxygen from easily flowing in from outside the battery module even if the resin bus bar frame 310 is damaged.

[0048] Therefore, the fireproof sheet 400 can minimize the possibility of a fire occurring near the bus bar frame 310 even when an event occurs inside the battery module, and can delay the fire from spreading inside the battery module even if a fire occurs near the bus bar frame 310. In addition, the fireproof sheet 400 can prevent a short circuit from occurring between the battery cells 100 due to damage to the bus bar frame 310, thereby preventing the event from spreading.

[0049] When the bus bar frame 310 includes the frame protrusions 310a, the fire protection sheet 400 may include at least one sheet hole 400a having a corresponding shape and formed at a position corresponding to the frame protrusions 310a for fastening to the bus bar frame 310. The frame protrusions 310a are inserted into the sheet hole 400a to fix the fire protection sheet 400.

[0050] 4 and 5, Fig. 6 shows a structure in which a fireproof sheet 400 is fastened to a fastening frame 230 of a module housing 200. In this case, the fastening frame 230 may have at least one fastening protrusion 230a protruding toward the fireproof sheet 400.

[0051] The fastening protrusions 230a may be provided in a number corresponding to the positions corresponding to the sheet holes 400a formed in the fireproof sheet 400. The fastening protrusions 230a are inserted into the sheet holes 400a to fix the fireproof sheet 400.

[0052] The module housing 200 including the fastening frame 230 may be entirely made of a metal material to ensure the rigidity of the battery module and to withstand high-temperature gases and sparks emitted when an internal event occurs. In this case, the fastening protrusions 230a may also be made of a metal material, thereby preventing the fastening portion between the fastening frame 230 and the fireproof sheet 400 from being damaged by high-temperature gases and sparks.

[0053] Meanwhile, a battery pack according to an embodiment of the present invention includes a battery module according to an embodiment of the present invention as described above. Also, an ESS according to an embodiment of the present invention includes a battery pack according to an aspect of the present invention as described above. Also, a vehicle according to an embodiment of the present invention includes a battery pack according to an embodiment of the present invention as described above. The vehicle includes an electric vehicle.

[0054] As described above, the present invention has been described using limited embodiments and drawings, but the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims.

[0055] Furthermore, the present invention preferably includes the following examples. [1] A battery module including: a cell stack formed by stacking a plurality of battery cells one above the other; a module housing including a base plate supporting the cell stack and a pair of side plates covering both sides of the cell stack and having a spark redirection portion formed by bending one longitudinal end of the side plate toward the cell stack; and a bus bar frame assembly including: a bus bar frame covering an opening formed on one longitudinal side of the module housing and coupled to one longitudinal side of the cell stack; and a bus bar frame assembly including bus bars disposed on the bus bar frame and coupled to electrode leads of the battery cells. [2] The battery module described in [1], wherein the spark redirection portion has a shape in which the side plate is bent twice in a direction perpendicular to the extension direction of the side plate. [3] The battery module according to [1] or [2], further comprising a fireproof sheet interposed between the bus bar frame assembly and the cell stack. [4] The battery module according to [3], wherein the fireproof sheet is made of mica material. [5] The battery module according to [3] or [4], wherein the fireproof sheet has a plurality of sheet slits through which the electrode leads of the battery cells pass. [6] The battery module described in [5], wherein the bus bar frame has a plurality of frame slits, and the sheet slits are formed in a number corresponding to the positions of the frame slits. [7] A battery module described in any one of [3] to [5], wherein the fireproof sheet has at least one sheet hole. [8] The busbar frame has at least one frame protrusion, and the frame protrusion is inserted into the sheet hole to secure the fireproof sheet. [7] A battery module as described in [7]. [9] The battery module according to [7] or [8], wherein the module housing further includes a fastening frame connecting the pair of spark redirection units.

[10] The battery module described in [9], wherein the fastening frame has at least one fastening protrusion, which is inserted into the sheet hole to secure the fireproof sheet.

[11] A battery pack including the battery module according to any one of [1] to

[10] .

[12]

[11] An ESS including the battery pack described in

[12]

[11] .

[13]

[11] A vehicle including the battery pack. [Explanation of symbols]

[0056] 100 battery cells 110 ···Pouch Case 120 Electrode lead 200 ···Module Housing 210 Base Plate 220 Side Plate 220a Spark redirection section 230 Fastening frame 230a...Fascinating protrusion 300 Busbar Frame Assembly 310 Busbar Frame 310a Frame protrusion 310b Frame slit 320 Busbar 320b Busbar slit 400 Fireproof Sheet 400a ···Seat hole 400b ···Sheet slit

Claims

1. a cell stack formed by stacking a plurality of battery cells; a module housing including a base plate that supports the cell stack, and a pair of side plates that cover both sides of the cell stack and have a spark redirection portion formed by bending one longitudinal side end of the side plate toward the cell stack.

2. The spark redirector includes: The battery module according to claim 1 , wherein the side plates are folded twice in a direction perpendicular to an extension direction of the side plates.

3. The battery module according to claim 1 or 2, further comprising a bus bar frame assembly including a bus bar frame supporting bus bars coupled to the battery cells.

4. The battery module includes: The battery module according to claim 3 , further comprising a fireproof sheet interposed between the bus bar frame assembly and the cell stack.

5. The fireproof sheet is The battery module according to claim 4 , wherein the material is mica.

6. The fireproof sheet is The battery module according to claim 4 or 5, comprising a plurality of sheet slits through which electrode leads of the battery cells pass.

7. the bus bar frame includes a plurality of frame slits; The battery module according to claim 6 , wherein the sheet slits are formed at positions corresponding to the frame slits and in a number corresponding to the frame slits.

8. The fireproof sheet is The battery module according to claim 4 , further comprising at least one sheet hole.

9. the busbar frame includes at least one frame protrusion; The battery module according to claim 8 , wherein the frame protrusions are inserted into the sheet holes to fix the fireproof sheet.

10. The battery module according to claim 8 or 9, wherein the module housing further comprises a fastening frame connecting the pair of spark redirectors.

11. The fastening frame has at least one fastening protrusion; The battery module according to claim 10 , wherein the fastening protrusions are inserted into the sheet holes to fix the fireproof sheet.

12. A battery pack comprising the battery module according to any one of claims 1 to 11.

13. 13. An ESS comprising the battery pack of claim 12.

14. A motor vehicle comprising the battery pack of claim 12.

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