Battery modules, battery packs containing them, and automobiles

Abstract

A battery module, a battery pack including the same, and an automobile are disclosed. A battery module according to one embodiment of the present invention includes a plurality of battery cells, a case housing the plurality of battery cells and having vent holes formed therein for the discharge of flames or gases, and a shielding member for blocking off portions of the case that do not have vent holes in the event of a thermal event.

Description

Technical Field

[0001] The present invention relates to a battery module, a battery pack including the same, and a vehicle, and more particularly, to a battery module capable of blocking a part of the battery module for smooth venting when a thermal event occurs, a battery pack including the same, and a vehicle.

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0118625 filed on September 6, 2023, and all of the contents disclosed in the specification and drawings of the application are incorporated into this application.

Background Art

[0003] As the development of technology for mobile devices and the demand for them increase, the demand for secondary batteries as an energy source is rapidly increasing. Nickel-cadmium batteries or hydrogen-ion batteries have been used as conventional secondary batteries, but recently, lithium secondary batteries, which have almost no memory effect compared to nickel-based secondary batteries, are freely chargeable and dischargeable, have a very low self-discharge rate, and have a high energy density, are widely used.

[0004] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate each coated with such a positive electrode active material and a negative electrode active material are arranged with a separator interposed therebetween, and an exterior material, that is, a battery case, for sealing and storing the electrode assembly together with an electrolytic solution.

[0005] Lithium secondary batteries consist of a positive electrode, a negative electrode, a separator interposed between them, and an electrolyte. Depending on the positive electrode active material and negative electrode active material used, they are classified into lithium-ion batteries (LIBs), lithium polymer batteries (PLIBs), etc. Typically, the electrodes of these lithium secondary batteries can be formed by coating a positive electrode active material or a negative electrode active material onto a current collector such as an aluminum or copper sheet, mesh, film, or foil and drying it.

[0006] Lithium-ion batteries have attracted attention due to their advantages such as high operating voltage and significantly higher energy density. However, because they use organic electrolytes, overcharging can induce overcurrent and overheating, potentially causing explosions or fires.

[0007] If a thermal event occurs from a battery cell within a battery module, the flame or gas generated in the battery cell can be discharged through vent holes formed at various locations.

[0008] In this case, depending on the orientation of the battery cells, electrode leads or busbars may be located on the side of the module case, and in this case, these electrode leads or busbars may make venting to the side difficult.

[0009] Therefore, if the electrode leads or busbars of the battery cells are located on the side of the module case, vent holes may be formed in the top or bottom of the module case so that flames or gases generated when a thermal event occurs can be vented from the top or bottom.

[0010] However, with conventional technology, even if vent holes are formed on the top or bottom of the module case, flames or gases generated during a thermal event may move to the sides of the module case before being discharged through the vent holes, resulting in problems with smooth upward or downward venting. [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] The present invention aims to provide a battery module that blocks the side of the battery module to facilitate ventilation in the other direction when a thermal event occurs, a battery pack including the same, and an automobile.

[0012] Another objective of the present invention is to provide a battery module, a battery pack including the same, and an automobile that can reduce the likelihood of a battery pack exploding by facilitating the venting of flames or gases, and that can prevent flames or gases from leaking out of the battery module through unspecified paths.

[0013] However, the technical problems that this invention aims to solve are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0014] According to one aspect of the present invention, a battery module may be provided that includes a plurality of battery cells, a case in which the plurality of battery cells are housed and which has vent holes formed therein for the discharge of flames or gases, and a shielding member that blocks off portions of the case in which vent holes are not formed when a thermal event occurs.

[0015] In one embodiment, the blocking member is housed inside the case before the occurrence of a thermal event, and can be pulled out from the case when the thermal event occurs.

[0016] In one embodiment, the blocking member may include an expansion portion housed in the case that expands when fluid is supplied to it, and a fluid supply portion that supplies fluid to the expansion portion.

[0017] In one embodiment, the vent hole is formed in the upper part of the case so that upward venting is possible when a thermal event occurs, and the shielding member may be positioned on the side of the case at the lower part of the case.

[0018] In one embodiment, the blocking member is balloon-shaped and can expand from the bottom to the top of the case when a thermal event occurs.

[0019] In one embodiment, when the expansion portion expands, the expansion portion may have a height corresponding to the battery cell.

[0020] In one embodiment, the battery cell is a pouch-type battery cell with electrode leads formed on its side surface, and the blocking member may be positioned in close proximity to the electrode leads.

[0021] In one embodiment, a partition wall is formed inside the case where the battery cells are arranged, and the blocking member may be formed at a position corresponding to the partition wall.

[0022] In one embodiment, the case is formed with a pocket portion that protrudes downward from the case, and the blocking member can be housed in the pocket portion of the case.

[0023] In one embodiment, the fluid supply unit may be provided as a carbon dioxide cartridge for supplying carbon dioxide (CO2).

[0024] In one embodiment, the system may include a sensor unit that senses the inside of the case, and a control unit that operates the fluid supply unit based on the sensing by the sensor unit.

[0025] In one embodiment, the sensor unit can sense the pressure, temperature, or gas amount inside the case.

[0026] In one embodiment, the control unit can control to open the fluid supply unit by sensing of the sensor unit.

[0027] According to another aspect of the present invention, a battery pack including the battery module described above can be provided, and further, an automobile including the battery module can be provided.

Advantages of the Invention

[0028] According to an embodiment of the present invention, at the time of occurrence of a thermal event, the side surface of the battery module can be blocked to facilitate venting to the other side.

[0029] Also, by facilitating the venting of flame or gas, the possibility of explosion of the battery pack can be reduced, and it can be prevented that the flame or gas flows out to the outside of the battery module through an unpredefined path.

[0030] However, the effects obtained from the present invention are not limited to the above-described effects, and other technical effects of the present invention not mentioned will be clearly understood by those skilled in the art from the following description of the invention.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0032] [Figure 1] It is a combined perspective view of a battery module according to an embodiment of the present invention. [Figure 2] It is an exploded perspective view of a battery module according to an embodiment of the present invention. [Figure 3] This figure shows the state of a battery module according to one embodiment of the present invention before the shut-off member is activated. [Figure 4] Figure 3 shows the state after the blocking member has been activated. [Figure 5] This is a view along arrow A in Figure 3. [Figure 6] This is an enlarged view of section B in Figure 5. [Figure 7] Figure 6 shows the state after the blocking member has been activated. [Figure 8] Figure 7 shows the blocking member before and after activation. [Figure 9] This figure shows a modified embodiment of Figure 7. [Figure 10] Figure 7 shows the blocking member before and after activation. [Figure 11] This figure schematically shows the configuration of a battery pack including a battery module according to each embodiment of the present invention. [Figure 12] This is a diagram illustrating an automobile including a battery pack according to each embodiment of the present invention. [Modes for carrying out the invention]

[0033] Preferred embodiments of the present invention will now be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather in a manner consistent with the technical idea of ​​the present invention, in accordance with the principle that the inventor himself may appropriately define the concepts of terms in order to best describe the invention. Accordingly, it should be understood that the embodiments described herein and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent the entirety of the technical idea of ​​the present invention, and that there may be a variety of equivalents and modifications that can be substituted therein at the time of this application.

[0034] The size of each component or specific part of a component in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity and ease of explanation. Therefore, the size of each component may not fully reflect its actual size. Specific descriptions of known functions or configurations related to the present invention will be omitted if they are deemed to unnecessarily obscure the gist of the invention.

[0035] As used herein, the terms “joining” or “connecting” include not only cases where one member is directly joined or directly connected to another member, but also cases where one member is indirectly joined or indirectly connected to another member via a connecting member.

[0036] Figure 1 is a coupled perspective view of a battery module according to one embodiment of the present invention, and Figure 2 is an exploded perspective view of a battery module according to one embodiment of the present invention.

[0037] Referring to Figures 1 and 2, a battery module 10 according to one embodiment of the present invention includes a plurality of battery cells 100, a case 200, and a blocking member 300.

[0038] Multiple battery cells 100 are provided. The battery cells 100 have diverse structures, and multiple battery cells 100 can be stacked in various ways.

[0039] The battery cell 100 may have a structure in which multiple unit cells arranged in the order of positive electrode plate / separator / negative electrode plate, or bi-cells arranged in the order of positive electrode plate / separator / negative electrode plate / separator / positive electrode plate / separator / negative electrode plate are stacked according to the battery capacity.

[0040] The battery cell 100 may be provided with electrode leads 110. The electrode leads 110 are a type of terminal that is exposed to the outside and connected to an external device, and may be made of a conductive material. The electrode leads 110 may include a positive electrode lead and a negative electrode lead.

[0041] The positive electrode lead and the negative electrode lead may be positioned in opposite directions along the longitudinal direction of the battery cell 100, or they may be positioned in the same direction relative to the longitudinal direction of the battery cell 100.

[0042] The battery cell 100 may be provided with a plurality of cartridges (not shown) that house the battery cell 100. Each cartridge (not shown) can be manufactured by injection molding of plastic, and a plurality of cartridges (not shown) with a housing for housing the battery cell 100 can be stacked. The cartridge assembly formed by stacking the plurality of cartridges (not shown) may be provided with connector elements or terminal elements.

[0043] The connector element may include various forms of electrical connection components or connection members for connecting to, for example, a BMS (Battery Management System, not shown) that provides data related to the voltage or temperature of the battery cell 100.

[0044] The terminal element includes a positive terminal and a negative terminal as main terminals connected to the battery cell 100. The terminal element is equipped with terminal bolts and can be electrically connected to the outside. On the other hand, the battery cell 100 can have a variety of shapes.

[0045] The case 200 houses multiple battery cells 100. The case 200 surrounds the battery cells 100, thereby protecting them from external vibrations or shocks.

[0046] The case 200 has vent holes 210 through which flames or gases are discharged. For example, referring to Figures 1 and 2, the vent holes 210 may be formed at the top of the case 200, but are not limited thereto. For example, the vent holes 210 may be formed at the bottom of the case 200 for downward venting.

[0047] In the following explanation, for the sake of clarity, we will focus on the case where the vent hole 210 is formed on the upper part of the case 200.

[0048] When multiple battery cells 100 are stacked to form a battery cell stack, the case 200 can be formed in a shape corresponding to the shape of the battery cell stack. For example, if the battery cell stack is formed in a hexahedral shape, the case 200 can also be formed in a corresponding hexahedral shape.

[0049] The case 200 can be manufactured, for example, by bending a plate made of a metal material, thereby allowing the case 200 to be manufactured as a single unit. When the case 200 is manufactured as a single unit, the joining process becomes simpler and easier. Alternatively, the case 200 can be provided as a separate unit and joined by welding or other means. However, the material of the case 200 is not limited to a metal material.

[0050] The shielding member 300 shields the portion of the case 200 where vent holes 210 are not formed when a thermal event occurs. Referring to Figure 2, the battery cell 100 may be a pouch-type battery cell 100 with electrode leads 110 formed on its side. If the battery cell 100 is a pouch-type battery cell 100, multiple battery cells 100 are stacked and housed in the case 200, so that the electrode leads 110 of the battery cells 100 are positioned on the side of the case 200.

[0051] Furthermore, because the electrode leads 110 of the battery cell 100 are positioned on the side of the case 200, the busbars (not shown) that are electrically connected to the electrode leads 110 are also located on the side of the case 200.

[0052] Thus, since electrode leads 110 and busbars (not shown) are positioned on the side of case 200, forming vent holes 210 on the side of case 200 may be inappropriate. That is, when a thermal event occurs, flames or gases will strike the electrode leads 110 or busbars (not shown), making it difficult to vent them to the side.

[0053] Therefore, as mentioned above, if the electrode leads 110 of the battery cell 100 are located on the side of the case 200, the vent holes 210 for releasing flames or gases in the event of a thermal event may be formed on the top of the case 200, thereby enabling upward venting.

[0054] However, flames or gases generated during a thermal event may travel through the gaps between the electrode leads 110 to the side of the case 200, which can prevent smooth upward venting.

[0055] Therefore, in the battery module 10 according to one embodiment of the present invention, when a thermal event occurs, the blocking member 300 blocks the side of the case 200, preventing flames or gases from moving to the side of the case 200. This guides the flames or gases to move to the upper part of the case 200 where the vent holes 210 are formed, thereby facilitating upward venting.

[0056] Figure 3 shows the state of a battery module according to one embodiment of the present invention before the shut-off member is activated, and Figure 4 shows the state after the shut-off member is activated as in Figure 3.

[0057] Referring to Figures 2 and 3, in this embodiment, the blocking member 300 may be positioned on the side of the case 200 to block off portions of the case 200 where vent holes 210 are not formed, for example, the side of the case 200, when a thermal event occurs. The blocking member 300 may be positioned in close proximity to the electrode leads 110. Multiple blocking members 300 may be provided and positioned in the space between the electrode leads 110.

[0058] Specifically, as shown in Figure 3, the blocking member 300 may be positioned on the side of the case 200, at the bottom of the case 200, but the position of the blocking member 300 is not limited to this.

[0059] Referring to Figures 3 and 4, the shut-off member 300 may be configured to be housed inside the case 200 before the occurrence of a thermal event and to be pulled out from the case 200 when the thermal event occurs. In Figures 3 and 4, the battery cell 100 is schematically shown with a dashed line to clearly show the shut-off member 300, and the electrode leads 110 are not shown.

[0060] Referring to Figure 3, the blocking member 300 may include an expansion section 310 and a fluid supply section 320. The expansion section 310 expands when fluid is supplied from the fluid supply section 320. Under normal conditions, before a thermal event occurs, the expansion section 310 is housed in the case 200.

[0061] In other words, before a thermal event occurs, the expansion section 310 is housed in the case 200 as shown in Figure 3, but when a thermal event occurs, the expansion section 310 expands as fluid is supplied from the fluid supply section 320, as shown in Figure 4.

[0062] When the expansion section 310 expands, it blocks the side of the case 200 as shown in Figure 4, thereby preventing flames or gases from moving to the side of the case 200. Here, the expansion section 310 can be made from various types of fire-resistant materials to withstand flames or gases (e.g., high-temperature gases).

[0063] The expansion portion 310 of the blocking member 300 can be formed into various shapes, and as shown in Figure 4, for example, it can be balloon-shaped. That is, when a thermal event occurs, the fluid supply unit 320 supplies fluid to the expansion portion 310, causing the expansion portion 310 to expand from the bottom to the top of the case 200, thereby blocking the side of the case 200. The expansion process of the expansion portion 310 can be seen in Figure 8.

[0064] Referring to Figure 4, when the expansion portion 310 expands, it may have a height corresponding to the battery cell 100. Here, the height corresponding to the battery cell 100 does not necessarily have to be the same height as the battery cell 100; it should be a height that is sufficient to adequately block the side of the case 200 so that flames or gases cannot move to the side of the case 200.

[0065] Figure 5 is a view along arrow A in Figure 3, Figure 6 is an enlarged view of part B in Figure 5, Figure 7 is a view of Figure 6 after the blocking member has been activated, and Figure 8 is a view of Figure 7 before and after the blocking member has been activated.

[0066] Referring to Figures 5 to 7, the expansion portion 310 may be positioned between the electrode leads 110 of the battery cell 100 so as to expand between the electrode leads 110 of the battery cell 100.

[0067] In this case, the blocking member 300 may be positioned so as not to interfere with the electrical coupling between the electrode lead 110 and the busbar (not shown). Before the occurrence of a thermal event, the expansion portion 310 is housed in the case 200, so the blocking member 300 does not interfere with the electrode lead 110 or the busbar (not shown).

[0068] However, if a thermal event occurs in any one of the battery cells 100, resulting in the emission of flames or gas, then an abnormal phenomenon has occurred in that battery cell 100, and it is acceptable for the expansion portion 310 to expand and interfere to some extent with the electrode leads 110 or busbars (not shown).

[0069] In a modified embodiment, a partition wall 600 (see Figure 2) in which the battery cell 100 is placed may be formed inside the case 200. The blocking member 300 may then be formed at a position corresponding to the partition wall 600. However, this is only one embodiment.

[0070] Referring to Figure 5, the case 200 may have a pocket portion 220 that protrudes downward from the case 200. The expanding portion 310 of the blocking member 300 can then be housed in the pocket portion 220 of the case 200. However, the position in which the pocket portion 220 is formed is not necessarily limited to this location.

[0071] The pocket portion 220 may be formed integrally with the case 200, or it may be manufactured separately and then attached to the case 200.

[0072] The fluid supply unit 320 supplies fluid to the expansion unit 310 when a thermal event occurs.

[0073] The fluid supplied from the fluid supply unit 320 to the expansion unit 310 can be of various types. For example, the fluid supply unit 320 may be provided as a carbon dioxide cartridge to supply carbon dioxide (CO2) to the expansion unit 310. When the fluid supply unit 320 supplies carbon dioxide to the expansion unit 310, it has the effect of rapidly moving the carbon dioxide into the expansion unit 310.

[0074] Furthermore, as mentioned above, the expansion section 310 can be made from fire-resistant material, but if the temperature of the flame or hot gas exceeds a predetermined range and the fire-resistant expansion section 310 is damaged, or if it is defective during the manufacturing process, carbon dioxide may leak out of the expansion section 310 when a thermal event occurs. In this case, carbon dioxide has the advantage of being able to act as a fire extinguishing agent because it has a high latent heat of vaporization and can absorb a large amount of heat.

[0075] However, the fluid supplied from the fluid supply unit 320 is not necessarily limited to carbon dioxide.

[0076] On the other hand, the expansion section 310 may be configured to expand by sensing from a sensor section 400 provided inside the case 200. For this purpose, a battery module 10 according to one embodiment of the present invention may include a sensor section 400 that senses the inside of the case 200, and a control unit 500 that operates the fluid supply section 320 by sensing from the sensor section 400. The control unit 500 can control the fluid supply section 320 by sensing from the sensor section 400.

[0077] The sensor unit 400 may be a sensor that senses the pressure inside the case 200. In this case, the control unit 500 may control the fluid supply unit 320 to open if the pressure inside the case 200 exceeds a preset pressure.

[0078] Alternatively, the sensor unit 400 may be a sensor that senses the temperature inside the case 200. In this case, the control unit 500 may control the fluid supply unit 320 to open if the temperature inside the case 200 exceeds a preset temperature.

[0079] Alternatively, the sensor unit 400 may be a sensor that senses the amount of gas inside the case 200. In this case, the control unit 500 may control the fluid supply unit 320 to open if the amount of gas inside the case 200 exceeds a preset amount of gas.

[0080] Figure 9 shows a modified embodiment of Figure 7, and Figure 10 shows the blocking member of Figure 7 before and after operation.

[0081] In the modified embodiments shown in Figures 9 and 10, the shape of the expansion portion 310 of the blocking member 300 differs from that in Figure 7, and the blocking area also differs. In Figure 7, the expansion portion 310 is formed in a shape similar to an ellipse, while in Figure 9, the expansion portion 310 is formed in a shape similar to a rectangle. However, the shape of the expansion portion 310 of the blocking member 300 is not limited to these.

[0082] Figure 11 is a schematic diagram showing the configuration of a battery pack including a battery module according to each embodiment of the present invention.

[0083] Referring to Figure 11, a battery pack 20 according to one embodiment of the present invention may include one or more battery modules 10 according to each embodiment of the present invention as described above. In addition to such battery modules 10, the battery pack 20 may further include a pack case 200 for housing such battery modules 10, and various devices for controlling the charging and discharging of the battery modules 10, such as a BMS, current sensor, fuse, etc.

[0084] Figure 12 is a diagram illustrating an automobile including a battery pack according to each embodiment of the present invention.

[0085] Referring to Figure 12, the automobile 30 according to one embodiment of the present invention may include the aforementioned battery module 10 or battery pack 20, and the battery pack 20 may include the battery module 10. The battery module 10 according to one embodiment of the present invention may be applied to the automobile 30, for example, a predetermined automobile that uses electricity, such as an electric vehicle or a hybrid vehicle.

[0086] In this specification, terms indicating direction such as up, down, left, right, front, and back are used. However, such terms indicate relative positions and are used only for the convenience of explanation. It is obvious to those skilled in the art that these positions can change depending on the position of the object in question, the observer's position, etc.

[0087] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and of course, various modifications and variations are possible within the equivalent scope of the technical concept of the present invention and the claims below by persons with ordinary skill in the art to which the present invention pertains. Therefore, the embodiments described above should be considered from an explanatory rather than restrictive viewpoint. That is, the true technical concept of the present invention is shown in the claims, and all differences within the equivalent scope thereto should be interpreted as being included in the present invention. [Industrial applicability]

[0088] The present invention relates to battery modules, battery packs containing the same, and automobiles, and is particularly applicable to the secondary battery industry. [Explanation of Symbols]

[0089] 10 Battery Modules 20 Battery Packs 30 automobiles 100 battery cells 110 electrode leads 200 cases 210 Venthole 220 Pocket section 300 Barrier 310 Expansion section 320 Fluid supply section 400 Sensor section 500 Control Unit 600 Bulkhead

Claims

1. Multiple battery cells, A case in which the aforementioned multiple battery cells are housed and which has vent holes formed therein from which flames or gases are discharged, A battery module including a shielding member that blocks off portions of the case where vent holes are not formed when a thermal event occurs.

2. The battery module according to claim 1, characterized in that the shielding member is housed inside the case before the occurrence of a thermal event, and is pulled out from the case when the thermal event occurs.

3. The aforementioned blocking member is The case contains an expansion section that expands when fluid is supplied, The battery module according to claim 2, further comprising a fluid supply unit that supplies fluid to the expansion unit.

4. The battery module according to claim 3, characterized in that the vent holes are formed in the upper part of the case to allow upward venting when a thermal event occurs, and the shielding member is positioned at the lower part of the case on the side of the case.

5. The battery module according to claim 4, characterized in that the shielding member has a balloon shape and expands from the bottom to the top of the case when a thermal event occurs.

6. The battery module according to claim 3, characterized in that when the expansion portion expands, the expansion portion has a height corresponding to the battery cell.

7. The aforementioned battery cell is a pouch-type battery cell with electrode leads formed on its side. The battery module according to claim 4, characterized in that the blocking member is located in close proximity to the electrode lead.

8. A partition wall is formed inside the case in which the battery cell is arranged. The battery module according to claim 3, characterized in that the blocking member is formed at a position corresponding to the partition wall.

9. The battery module according to claim 2, characterized in that the case has a pocket portion that protrudes downward from the case, and the blocking member is housed in the pocket portion of the case.

10. The aforementioned fluid supply unit supplies carbon dioxide (CO2). ２ The battery module according to claim 3, characterized in that it is provided as a carbon dioxide cartridge that supplies )

11. A sensor unit that senses the inside of the case, The battery module according to claim 3, further comprising a control unit that operates the fluid supply unit based on sensing by the sensor unit.

12. The battery module according to claim 11, characterized in that the sensor unit senses the pressure, temperature, or gas volume inside the case.

13. The battery module according to claim 11, characterized in that the control unit controls the fluid supply unit to open based on sensing by the sensor unit.

14. A battery pack comprising a battery module according to any one of claims 1 to 13.

15. An automobile comprising a battery module according to any one of claims 1 to 13.

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