Battery module and battery pack including same and vehicle including same

Abstract

A battery module, and a battery pack and a vehicle each including same are disclosed. The battery module according to an embodiment of the present invention comprises: a plurality of battery cells; a case in which the plurality of battery cells are accommodated and a venting hole through which flame or gas is discharged is formed; and a blocking member for blocking, during a thermal event, a portion of the case, in which the venting hole is not formed.

Description

Battery modules, battery packs containing the same, and vehicles

[0001] This application claims priority to Korean Patent Application No. 10-2023-0118625, filed on September 6, 2023, and all contents disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0002] 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 portion of the battery module for smooth venting during a thermal event, a battery pack including the same, and a vehicle.

[0003] As technological development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing. Nickel-cadmium batteries or hydrogen-ion batteries were used as secondary batteries in the past, but recently, lithium secondary batteries are widely used because they have almost no memory effect compared to nickel-based secondary batteries, are free to charge and discharge, have a very low self-discharge rate, and have a high energy density.

[0004] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. Lithium secondary batteries comprise an electrode assembly comprising positive and negative plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between them, and an outer case, i.e., a battery case, that seals and encloses the electrode assembly together with an electrolyte.

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

[0006] Lithium secondary batteries are currently in the spotlight due to their advantages such as high operating voltage and significantly higher energy density. However, because they use organic electrolytes, there is a problem that lithium secondary batteries can cause overcurrent and overheating when overcharged, which in severe cases can cause fire due to explosion or ignition.

[0007] When a thermal event occurs from a battery cell installed in a battery module, flames or gases generated from the battery cell can be discharged through venting holes formed at various locations.

[0008] Here, depending on the arrangement direction of the battery cells, electrode leads or bus bars may be located on the side of the module case, and in this case, venting to the side may not be easy due to the electrode leads or bus bars.

[0009] Accordingly, when the electrode leads or bus bars of the battery cells are positioned on the side of the module case, a venting hole may be formed at the top or bottom of the module case so that flames or gases generated during a thermal event are vented through the top or bottom.

[0010] However, in the case of the conventional technology, even if a venting hole is formed at the top or bottom of the module case, there is a problem that the upper venting or lower venting is not smooth because the flame or gas generated during a thermal event can move to the side of the module case before being discharged through the venting hole.

[0011] Accordingly, the technical problem to be achieved by the present invention is to provide a battery module capable of blocking the side of the battery module when a thermal event occurs to facilitate venting in another direction, a battery pack including the same, and a vehicle.

[0012] In addition, the present invention provides a battery module, a battery pack and a vehicle including the same, which can reduce the possibility of explosion of the battery pack by facilitating venting of flame or gas and can prevent flame or gas from leaking out of the battery module through an unpredictable path.

[0013] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0014] According to one aspect of the present invention, a battery module may be provided, comprising: a plurality of battery cells; a case in which the plurality of battery cells are accommodated and in which a venting hole is formed through which flames or gases are discharged; and a blocking member that blocks a portion of the case in which the venting hole is not formed in the case during a thermal event.

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

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

[0017] In one embodiment, the venting hole may be formed on the upper side of the case to enable upper venting during a thermal event, and the blocking member may be disposed on the lower side of the case from the side of the case.

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

[0019] In one embodiment, when the expansion member is expanded, the expansion member may have a height corresponding to the battery cell.

[0020] In one embodiment, the battery cell is a pouch-shaped battery cell having electrode leads formed on the side, and the blocking member can be positioned close to the electrode leads.

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

[0022] In one embodiment, the case has a pocket portion formed that protrudes toward the lower side of the case, and the blocking member can be stored in the pocket portion of the case.

[0023] In one embodiment, the fluid supply unit may be provided with a carbon dioxide cartridge that supplies carbon dioxide (CO2).

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

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

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

[0027] Meanwhile, according to another aspect of the present invention, a battery pack including the above-described battery module can be provided, and further, a vehicle including the battery module can be provided.

[0028] Embodiments of the present invention have the effect of blocking the side of the battery module when a thermal event occurs, thereby facilitating venting in other directions.

[0029] In addition, it has the effect of reducing the possibility of explosion of the battery pack by facilitating venting of flame or gas, and preventing flame or gas from leaking out of the battery module through a non-predetermined path.

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

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

[0032] Figure 1 is a perspective view of a combined battery module according to one embodiment of the present invention.

[0033] Figure 2 is an exploded perspective view of a battery module according to one embodiment of the present invention.

[0034] FIG. 3 is a drawing showing the state of a blocking member before operation in a battery module according to one embodiment of the present invention.

[0035] Figure 4 is a drawing showing the operation of the blocking member from Figure 3.

[0036] Figure 5 is a drawing viewed along arrow A of Figure 3.

[0037] Figure 6 is an enlarged view of part B of Figure 5.

[0038] Fig. 7 is a drawing showing the operation of the blocking member from Fig. 6.

[0039] Figure 8 is a drawing showing the blocking member of Figure 7 before and after operation.

[0040] Fig. 9 is a drawing illustrating a modified embodiment of Fig. 7.

[0041] Figure 10 is a drawing showing the blocking member of Figure 7 before and after operation.

[0042] FIG. 11 is a schematic diagram showing the configuration of a battery pack including a battery module according to each embodiment of the present invention.

[0043] FIG. 12 is a drawing for explaining a vehicle including a battery pack according to each embodiment of the present invention.

[0044] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Terms or words used in this specification and claims should not be interpreted as limited to their conventional or dictionary meanings, but should be interpreted with meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to best explain his or her own invention. Therefore, it should be understood that the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical idea of ​​the present invention, and various equivalents and modifications may exist as of the time of this application.

[0045] In the drawings, the sizes of each component or specific parts of that component are exaggerated, omitted, or schematically illustrated for convenience and clarity of explanation. Therefore, the size of each component does not entirely reflect its actual size. If a detailed description of a related known function or configuration is deemed to unnecessarily obscure the gist of the present invention, such description will be omitted.

[0046] The term 'joint' or 'connection' as used herein includes 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 through a connecting member.

[0047] FIG. 1 is a perspective view of a combined battery module according to one embodiment of the present invention, and FIG. 2 is a perspective view of a disassembled battery module according to one embodiment of the present invention.

[0048] Referring to FIGS. 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).

[0049] Battery cells (100) are provided in multiples. The battery cells (100) may have various structures, and furthermore, the plurality of battery cells (100) may be stacked in various ways.

[0050] The battery cell (100) may have a structure in which a plurality of unit cells arranged in the order of positive plate-separator-negative plate or bi-cells arranged in the order of positive plate-separator-negative plate-separator-positive plate-separator-negative plate are stacked according to the battery capacity.

[0051] The battery cell (100) may be equipped with an electrode lead (110). The electrode lead (110) is 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 lead (110) may include a positive electrode lead and a negative electrode lead.

[0052] The positive electrode lead and the negative electrode lead may be positioned in opposite directions with respect to the longitudinal direction of the battery cell (100), or the positive electrode lead and the negative electrode lead may be positioned in the same direction with respect to the longitudinal direction of the battery cell (100).

[0053] A battery cell (100) may be combined with a plurality of cartridges (not shown) that accommodate the battery cell (100). Each cartridge (not shown) may be manufactured by injection molding plastic, and a plurality of cartridges (not shown) each having a storage portion capable of accommodating the battery cell (100) may be stacked. A cartridge assembly in which a plurality of cartridges (not shown) are stacked may be equipped with a connector element or a terminal element.

[0054] The connector element may include various types of electrical connection components or connecting members for connection to, for example, a BMS (Battery Management System, not shown) that can provide data on the voltage or temperature of the battery cell (100).

[0055] In addition, the terminal element is a main terminal connected to the battery cell (100) and includes a positive terminal and a negative terminal. The terminal element is provided with a terminal bolt so that it can be electrically connected to the outside. Meanwhile, the battery cell (100) may have various shapes.

[0056] A plurality of battery cells (100) are stored in the case (200). In addition, the case (200) surrounds the battery cells (100) and thereby protects the battery cells (100) from external vibrations or shocks.

[0057] A venting hole (210) is formed in the case (200) through which flames or gases are discharged. For example, referring to FIGS. 1 and 2, the venting hole (210) may be formed on the upper side of the case (200), but is not limited thereto. For example, the venting hole (210) may be formed on the lower side of the case (200) for lower venting.

[0058] For convenience of explanation, the following description focuses on the case where the venting hole (210) is formed on the upper side of the case (200).

[0059] When a plurality of battery cells (100) are stacked to form a battery cell stack, the case (200) may be formed in a shape corresponding to the shape of the battery cell stack. For example, when the battery cell stack is formed in a hexahedral shape, the case (200) may also be formed in a hexahedral shape corresponding to this.

[0060] The case (200) can be manufactured, for example, by bending a metal plate, thereby enabling the case (200) to be manufactured as an integral part. When the case (200) is manufactured as an integral part, the joining process is simplified and simplified. Alternatively, the case (200) may be provided in a detachable form and joined by welding or the like. However, the material of the case (200) is not limited to a metal material.

[0061] The blocking member (300) blocks a portion of the case (200) where the venting hole (210) is not formed in the case of a thermal event. Referring to FIG. 2, the battery cell (100) may be a pouch-type battery cell (100) having electrode leads (110) formed on the side. In the case where the battery cell (100) is a pouch-type battery cell (100), when a plurality of battery cells (100) are stacked and stored in the case (200), the electrode leads (110) of the battery cells (100) are arranged on the side of the case (200).

[0062] And, when the electrode lead (110) of the battery cell (100) is placed on the side of the case (200), a bus bar (not shown) electrically connected to the electrode lead (110) is also located on the side of the case (200).

[0063] In this way, since the electrode leads (110) and bus bars (not shown) are arranged on the side of the case (200), it may not be appropriate to form a venting hole (210) on the side of the case (200). That is, when a thermal event occurs, flames or gases collide with the electrode leads (110) or bus bars (not shown), making it difficult to discharge them to the side.

[0064] Accordingly, as described above, when the electrode lead (110) of the battery cell (100) is placed on the side of the case (200), a venting hole (210) for discharging flame or gas in the event of a thermal event can be formed on the upper side of the case (200), thereby enabling upper venting.

[0065] However, flames or gases generated during a thermal event may move to the side of the case (200) through the spaced gap between the electrode leads (110), in which case upper venting may not be smooth.

[0066] Accordingly, the battery module (10) according to one embodiment of the present invention has the effect of preventing flames or gases from moving to the side of the case (200) by having the blocking member (300) block the side of the case (200) in the event of a thermal event, thereby inducing the flames or gases to move to the upper side of the case (200) where the venting hole (210) is formed, thereby facilitating upper venting.

[0067] FIG. 3 is a drawing showing the state of a blocking member before operation in a battery module according to one embodiment of the present invention, and FIG. 4 is a drawing showing the state of a blocking member after operation from FIG. 3.

[0068] Referring to FIGS. 2 and 3, in the present embodiment, the blocking member (300) may be placed on the side of the case (200) to block a portion of the case (200) where the venting hole (210) is not formed, for example, the side of the case (200), in the event of a thermal event. In addition, the blocking member (300) may be positioned close to the electrode leads (110). A plurality of blocking members (300) may be provided and placed in the space between the electrode leads (110).

[0069] Specifically, as shown in FIG. 3, the blocking member (300) may be placed on the lower side of the case (200) from the side of the case (200), but the position of the blocking member (300) is not limited thereto.

[0070] Referring to FIGS. 3 and 4, the blocking member (300) may be configured to be housed inside the case (200) before a thermal event occurs and to be withdrawn from the case (200) when a thermal event occurs. In FIGS. 3 and 4, in order to clearly illustrate the blocking member (300), the battery cell (100) is schematically indicated with a dotted line, and the electrode lead (110) is not illustrated.

[0071] Referring to FIG. 3, the blocking member (300) may include an expansion member (310) and a fluid supply member (320). The expansion member (310) receives fluid from the fluid supply member (320) and expands. In a typical situation before a thermal event occurs, the expansion member (310) is housed in a case (200).

[0072] That is, before a thermal event occurs, the expansion unit (310) is housed in the case (200) as in FIG. 3, but when a thermal event occurs, the expansion unit (310) receives fluid from the fluid supply unit (320) and expands as in FIG. 4.

[0073] And, when the expansion member (310) expands, it blocks the side of the case (200) as shown in Fig. 4, thereby preventing flame or gas from moving to the side of the case (200). Here, the expansion member (310) can be made of various types of fire-resistant materials so as to withstand flame or gas (e.g., high-temperature gas).

[0074] The expansion portion (310) of the blocking member (300) can be formed in various shapes, and with reference to FIG. 4, for example, it can be in the shape of a balloon. That is, when the fluid supply portion (320) supplies fluid to the expansion portion (310) during a thermal event, the expansion portion (310) can inflate from the lower side of the case (200) and expand upward to block the side of the case (200). The expansion process of the expansion portion (310) can be described with reference to FIG. 8.

[0075] Referring to FIG. 4, when the expansion member (310) is expanded, the expansion member (310) 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), and means a height that can sufficiently block the side of the case (200) to prevent flames or gases from moving to the side of the case (200).

[0076] FIG. 5 is a drawing viewed along arrow A of FIG. 3, FIG. 6 is an enlarged view of part B of FIG. 5, FIG. 7 is a drawing showing after operation of the blocking member from FIG. 6, and FIG. 8 is a drawing showing before and after operation of the blocking member of FIG. 7.

[0077] Referring to FIGS. 5 to 7, the expansion member (310) can be placed between the electrode leads (110) of the battery cell (100) so as to expand between the electrode leads (110) of the battery cell (100).

[0078] In this case, the blocking member (300) can be positioned so as not to interfere with the electrical connection of the electrode lead (110) and the bus bar (not shown). Since the expansion member (310) is housed in the case (200) before the thermal event occurs, the blocking member (300) does not interfere with the electrode lead (110) or the bus bar (not shown).

[0079] However, if a thermal event occurs in one of the battery cells (100) and flames or gas are emitted, it is an abnormality in the battery cell (100), so it may be acceptable for the expansion portion (310) to expand and interfere to some extent with the electrode lead (110) or bus bar (not shown).

[0080] Meanwhile, as a modified embodiment, a partition wall (600, see FIG. 2) in which a battery cell (100) is arranged may be formed inside the case (200). In addition, a blocking member (300) may be formed at a position corresponding to the partition wall (600). However, this is only one embodiment.

[0081] Referring to FIG. 5, a pocket portion (220) protruding toward the lower side of the case (200) may be formed in the case (200). In addition, the expansion portion (310) of the blocking member (300) may be accommodated in the pocket portion (220) of the case (200). However, the formation location of the pocket portion (220) is not necessarily limited thereto.

[0082] The pocket part (220) may be formed integrally with the case (200) or may be manufactured separately and then combined with the case (200).

[0083] The fluid supply unit (320) supplies fluid to the expansion unit (310) when a thermal event occurs.

[0084] The fluid supplied from the fluid supply unit (320) to the expansion unit (310) may be various. For example, the fluid supply unit (320) may be provided with 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), the carbon dioxide has the effect of moving quickly to the expansion unit (310).

[0085] In addition, as described above, the expansion member (310) may be manufactured from a refractory material, but if the temperature of the flame or high-temperature gas exceeds a preset range and the refractory expansion member (310) is damaged, or if there is a defect in the manufacturing process, carbon dioxide may leak out from the expansion member (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.

[0086] However, the fluid supplied from the fluid supply unit (320) is not necessarily limited to carbon dioxide.

[0087] Meanwhile, the expansion unit (310) may be configured to expand in response to sensing by the sensor unit (400) installed inside the case (200). To this end, the battery module (10) according to one embodiment of the present invention may include a sensor unit (400) that senses the inside of the case (200), and a control unit (500) that operates the fluid supply unit (320) in response to sensing by the sensor unit (400). The control unit (500) may control the fluid supply unit (320) in response to sensing by the sensor unit (400).

[0088] 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 when the pressure inside the case (200) exceeds a preset pressure.

[0089] 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 be opened when the temperature inside the case (200) exceeds a preset temperature.

[0090] 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 when the amount of gas inside the case (200) exceeds a preset amount of gas.

[0091] Fig. 9 is a drawing showing a modified embodiment of Fig. 7, and Fig. 10 is a drawing showing the blocking member of Fig. 7 before and after operation.

[0092] The modified embodiments of FIGS. 9 and 10 differ from those of FIG. 7 in the shape of the expansion portion (310) of the blocking member (300) and also in the blocking area. In the case of FIG. 7, the expansion portion (310) is formed in a shape similar to an oval, while in the case of FIG. 9, the expansion portion (310) is formed in a shape similar to a square. However, the shape of the expansion portion (310) of the blocking member (300) is not limited thereto.

[0093] FIG. 11 is a schematic diagram showing the configuration of a battery pack including a battery module according to each embodiment of the present invention.

[0094] Referring to FIG. 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, the battery pack (20) may further include, in addition to the battery module (10), a pack case (200) for storing the battery module (10), and various devices for controlling charging and discharging of the battery module (10), such as a BMS, a current sensor, a fuse, etc.

[0095] FIG. 12 is a drawing for explaining a vehicle including a battery pack according to each embodiment of the present invention.

[0096] Referring to FIG. 12, a vehicle (30) according to one embodiment of the present invention may include the battery module (10) or battery pack (20) described above, and the battery pack (20) may include the battery module (10). In addition, the battery module (10) according to one embodiment of the present invention may be applied to a vehicle (30), for example, a vehicle designed to use electricity, such as an electric vehicle or a hybrid vehicle.

[0097] In this specification, when terms indicating directions such as up, down, left, and right are used, these terms are only for convenience of explanation, and it is obvious to those skilled in the art that these terms may vary depending on the location of the target object or the location of the observer.

[0098] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and those skilled in the art to which the present invention pertains may make various modifications and variations within the scope of the technical spirit of the present invention and the equivalent scope of the claims to be described below. Therefore, the embodiments disclosed above should be considered in an illustrative rather than a restrictive sense. In other words, the true scope of the technical spirit of the present invention is set forth in the claims, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

[0099] The present invention relates to a battery module, a battery pack including the same, and an automobile, and is particularly applicable to industries related to secondary batteries.

Claims

1. Multiple battery cells; A case in which the plurality of battery cells are stored and a venting hole is formed through which flames or gases are discharged; and A battery module including a blocking member that blocks a portion of the case where a venting hole is not formed during a thermal event.

2. In paragraph 1, A battery module characterized in that the blocking member is housed inside the case before a thermal event occurs and is withdrawn from the case when the thermal event occurs.

3. In paragraph 2, The above blocking member is, An expansion unit that is housed in the case and expands by receiving a fluid; and A battery module characterized by including a fluid supply unit that supplies fluid to the expansion unit.

4. In paragraph 3, A battery module characterized in that the venting hole is formed on the upper side of the case to enable upper venting during a thermal event, and the blocking member is arranged on the lower side of the case from the side of the case.

5. In paragraph 4, A battery module characterized in that the above-mentioned blocking member is in the shape of a balloon and inflates from the lower side of the case to the upper side when a thermal event occurs.

6. In paragraph 3, A battery module characterized in that when the expansion member is expanded, the expansion member has a height corresponding to the battery cell.

7. In paragraph 4, The above battery cell is a pouch-type battery cell with electrode leads formed on the side. A battery module characterized in that the above blocking member is positioned close to the electrode lead.

8. In paragraph 3, A bulkhead is formed inside the case in which the battery cells are placed, A battery module characterized in that the above blocking member is formed at a position corresponding to the bulkhead.

9. In paragraph 2, A battery module characterized in that the case has a pocket portion protruding from the lower side of the case, and the blocking member is stored in the pocket portion of the case.

10. In paragraph 3, A battery module characterized in that the fluid supply unit is provided with a carbon dioxide cartridge that supplies carbon dioxide (CO2).

11. In paragraph 3, A sensor unit that senses the inside of the case; and A battery module characterized by including a control unit that operates the fluid supply unit according to sensing of the sensor unit.

12. In paragraph 11, A battery module characterized in that the sensor unit senses the pressure, temperature, or amount of gas inside the case.

13. In paragraph 11, A battery module characterized in that the control unit controls the fluid supply unit to open according to sensing of the sensor unit.

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

15. A vehicle comprising a battery module according to any one of claims 1 to 13.

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