Battery packs and automobiles containing them

Abstract

A battery pack and an automobile including the same are disclosed. A battery pack according to one embodiment of the present invention includes a plurality of battery modules in which a number of battery cells are stacked, and a pack case in which the plurality of battery modules are housed, wherein at least a portion of the pack case has an exhaust path formed for exhausting flames or gases generated in the battery cells.

Description

Technical Field

[0001] The present invention relates to a battery pack and a vehicle including the same, and more particularly, to a battery pack in which heat is uniformly diffused and gas is smoothly discharged when a thermal event occurs, and a vehicle including the same.

[0002] This application claims priority based on Korean Patent Application No. 10-2024-0048904 filed on April 11, 2024, and all the contents disclosed in the specification and drawings of the application are incorporated herein.

Background Art

[0003] Generally, a secondary battery refers to a battery that can be repeatedly charged and discharged, such as a lithium-ion battery, a lithium polymer battery, a nickel cadmium battery, a nickel metal hydride battery, or a nickel zinc battery. A basic battery cell can provide an output voltage of about 2.5V to 4.2V.

[0004] Recently, as such battery cells are applied to devices that require a high output voltage and a large charge capacity, such as electric vehicles (EVs) and energy storage systems (ESSs), a battery module configured by connecting a plurality of battery cells in series, parallel, or a combination of series and parallel, and a battery pack configured by further connecting such battery modules in series, parallel, or a combination of series and parallel are widely used.

[0005] Lithium secondary batteries have attracted attention due to advantages such as a high operating voltage and a much higher energy density. However, since an organic electrolyte is used, when a lithium secondary battery is overcharged, it induces overcurrent and overheating, and ultimately causes problems such as fires due to explosion or ignition.

[0006] Various types of secondary batteries may include battery modules, in which multiple battery cells are stacked and placed in a module case that protects the battery cells, and battery packs, which contain multiple battery modules.

[0007] Figure 1 is a perspective view of a conventional battery pack.

[0008] Referring to Figure 1, in the case of a conventional battery pack 1, when a thermal event occurs, the flame or gas is blocked by the upper frame 2 of the battery pack 1 and cannot be expelled upward, instead moving to the left or right (see arrow in Figure 1), and the internal pressure increases, making the likelihood of explosion of the battery module 3 or battery pack 1 higher.

[0009] In this scenario, if an explosion occurs in battery module 2 where the flame originated, the flame may spread to other battery modules 2, causing a thermal runaway phenomenon. If the flame escapes to the outside due to such a thermal runaway phenomenon, there is a problem that the driver of the electric vehicle may be burned or put in a dangerous situation.

[0010] Alternatively, there is a problem in that the battery module 2 or battery pack 1 may be damaged or completely burned due to a chain reaction of flames caused by flame propagation, making it difficult to ensure the safety of the battery module 2 or battery pack 1. [Overview of the project] [Problems that the invention aims to solve]

[0011] The present invention aims to provide a battery pack and an automobile including it that have a uniform heat distribution by preventing heat concentration or thermal energy trapping phenomena by ensuring that when a flame is generated from any one of the battery cells, the flame and the heat generated by the flame are uniformly diffused within the battery pack.

[0012] Another objective of the present invention is to provide a battery pack and an automobile including it, in which gas is easily discharged by facilitating smooth venting.

[0013] Another objective is to provide a battery module capable of preventing thermal runaway phenomena by preventing a chain reaction of flames caused by flame propagation, a battery pack including the same, and an automobile.

[0014] 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]

[0015] According to one aspect of the present invention, a battery pack may be provided that includes a plurality of battery modules in which a plurality of battery cells are stacked, and a pack case in which the plurality of battery modules are housed, wherein at least a portion of the pack case is provided with an exhaust path formed therein for exhausting flames or gases generated in the battery cells.

[0016] In one embodiment, the pack case includes an upper frame, and the discharge path may be formed in the upper frame.

[0017] In one embodiment, the inside of the upper frame may be hollow to allow flames or gases to move.

[0018] In one embodiment, the upper frame is formed with connecting holes, and the battery module can be connected to the connecting holes.

[0019] In one embodiment, the battery module includes an upper module case, the upper module case has an exhaust hole through which flames or gases are discharged, and the exhaust hole can be connected to the exhaust path of the pack case.

[0020] In one embodiment, a connecting portion connecting the discharge hole and the discharge path may be included.

[0021] In one embodiment, the connecting portion may be composed of a gasket or a sealing member so that flame or gas does not leak.

[0022] In one embodiment, a backflow prevention member provided on the upper frame may be included to prevent backflow of flame or gas.

[0023] In one embodiment, the backflow prevention member may be configured to rotate by flame or gas.

[0024] In one embodiment, the backflow prevention member may include a rotation shaft coupled to the upper surface of the upper frame, and a first opening / closing portion rotatably coupled to the rotation shaft and contacting the lower surface of the upper frame.

[0025] In one embodiment, the backflow prevention member may include a protrusion protruding from the upper frame, an elastic portion coupled to the protrusion, and a second opening / closing portion coupled to the elastic portion.

[0026] In one embodiment, the protrusion may include a first protrusion protruding from the upper surface of the upper frame, and a second protrusion protruding from the lower surface of the upper frame at a position corresponding to the position of the first protrusion and spaced apart from the first protrusion by a preset interval.

[0027] In one embodiment, the elastic portion may include a first elastic portion coupled to the first protrusion, and a second elastic portion coupled to the second protrusion.

[0028] In one embodiment, a path expansion member provided on the upper frame may be included to expand the discharge path of flame or gas.

[0029] In one embodiment, the path extension member includes at least one first protrusion protruding from the first portion of the upper frame and at least one second protrusion protruding from the second portion of the upper frame, and the first protrusion and the second protrusion may be alternately arranged.

[0030] In one embodiment, the path extension member includes at least one first protrusion protruding from the first portion of the upper frame and at least one second protrusion protruding from the second portion of the upper frame, the first protrusion is arranged to incline toward the second portion, and the second protrusion may be arranged to incline toward the first portion.

[0031] According to another aspect of the present invention, an automobile including at least one of the above-described battery packs may be provided.

Advantages of the Invention

[0032] According to an embodiment of the present invention, when a flame occurs from any one battery cell, inside the battery pack, the flame and the heat generated by the flame are evenly diffused to prevent heat concentration or heat energy trapping phenomenon, so that a uniform heat distribution can be achieved.

[0033] In addition, venting becomes smooth, so that gas can be easily discharged.

[0034] In addition, a chain reaction of the flame due to flame propagation can be prevented, and a thermal runaway phenomenon can be prevented.

[0035] However, the effects of the present invention are not limited to the above-described effects, and other effects of the present invention not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Brief Description of the Drawings

[0036] [Figure 1] It is a perspective view of a conventional battery pack. [Figure 2]This is a perspective view of a battery pack according to a first embodiment of the present invention. [Figure 3] This is an exploded perspective view of a battery pack according to the first embodiment of the present invention. [Figure 4] This is a cross-sectional view along line A-A' in Figure 2. [Figure 5] This is an enlarged view of section B in Figure 3. [Figure 6] Figure 5 shows how the connector is attached to the battery module. [Figure 7] This is a cross-sectional view of a battery pack according to a second embodiment of the present invention. [Figure 8] This is a cross-sectional view of a battery pack according to a third embodiment of the present invention. [Figure 9] This is a plan view of a part of a battery pack according to a fourth embodiment of the present invention. [Figure 10] This is a plan view of a part of a battery pack according to a fifth embodiment of the present invention. [Figure 11] 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]

[0037] 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.

[0038] 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.

[0039] 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.

[0040] Figure 2 is a perspective view of a battery pack according to the first embodiment of the present invention, and Figure 3 is an exploded perspective view of the battery pack according to the first embodiment of the present invention. Figure 4 is a cross-sectional view along line A-A' in Figure 2, and Figure 5 is an enlarged view of part B in Figure 3. Figure 6 shows the battery module of Figure 5 with the connecting part connected.

[0041] Referring to Figures 2 to 4, the battery pack 10 according to the first embodiment of the present invention may be configured to include a plurality of battery modules 100 and a pack case 200.

[0042] Multiple battery modules 100 can be provided and arranged in various ways. For example, they can be arranged horizontally and vertically as shown in Figure 3, but are not limited to this.

[0043] Referring to Figure 4, the battery module 100 may comprise a plurality of battery cells 110 and a module case 120.

[0044] Multiple battery cells 110 can be stacked on top of each other. The battery cells 110 have diverse structures, and multiple battery cells 110 can be stacked in various ways.

[0045] The battery cell 110 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.

[0046] The battery cell 110 may be provided with electrode leads. Electrode leads are a type of terminal exposed to the outside and connected to external devices, and may be made of a conductive material. Electrode leads may include a positive electrode lead and a negative electrode lead.

[0047] The positive electrode lead and the negative electrode lead may be positioned on opposite sides of the battery cell 110 in the longitudinal direction, or they may be positioned on the same side of the battery cell 110 in the longitudinal direction.

[0048] The battery cell 110 may comprise a plurality of cartridges (not shown) that house the battery cell 110. Each cartridge (not shown) may be manufactured by plastic injection molding, and a plurality of cartridges (not shown) having a housing for housing the battery cell 110 may be stacked. A cartridge assembly formed by stacking a plurality of cartridges (not shown) may be provided with connector elements or terminal elements.

[0049] The connector element may include various forms of electrical connection components or connection members for connecting to, for example, a Battery Management System (BMS) (not shown) that can provide data relating to the voltage or temperature of the battery cell 110.

[0050] The terminal element is a main terminal connected to the battery cell 110, and includes a positive terminal and a negative terminal. The terminal element can be electrically connected to the outside by being provided with terminal bolts. On the other hand, the battery cell 110 can have a variety of shapes.

[0051] Referring to Figure 4, multiple battery cells 110 are stacked and housed in the module case 120. The module case 120 surrounds the multiple battery cells 110, thereby protecting the battery cells 110 from external vibrations and shocks.

[0052] The module case 120 can be formed in a shape corresponding to the shape of a stack of multiple battery cells 110. For example, if the stack of multiple battery cells 110 is formed in a hexahedral shape, the module case 120 can also be formed in a corresponding hexahedral shape, but is not limited to this. Here, the module case 120 may include an upper module case 121, a lower module case 122, and a side module case 123.

[0053] Furthermore, the module case 120 can be manufactured, for example, by bending a plate of metal material, thereby allowing the module case 120 to be manufactured as a single unit. When the module case 120 is manufactured as a single unit, it has the effect of simplifying the joining process. Alternatively, the module case 120 can be provided as a separate unit and joined by welding or the like. However, the material of the module case 120 is not limited to metal material.

[0054] Referring to Figures 3 and 4, the pack case 200 houses multiple battery modules 100. The pack case 200 may be composed of, for example, an upper frame 210, a lower frame 220, a side frame 230, and a partition frame 240. At least a portion of the pack case 200 has an exhaust path 211 through which flames or gases generated in the battery cells 110 are discharged.

[0055] The upper frame 210 is coupled to the side frame 230. The discharge path 211 can be formed in the upper frame 210. Referring to Figure 4, for example, the inside of the upper frame 210 is hollow, and the internal cavity of the upper frame 210 serves as the discharge path 211. The flame or gas generated from the battery cell 110 can be configured to travel through the internal cavity of the upper frame 210.

[0056] Here, the flame or gas may be configured to move in only one direction of the upper frame 210, or it may be configured to move in both directions of the upper frame 210.

[0057] Referring to Figure 4, the upper frame 210 may have connecting holes 212, and the battery module 100 may be connected to the connecting holes 212 so that flames or gases generated from the battery cells 110 can move from the connecting holes 212 into the internal cavity of the upper frame 210.

[0058] To explain this in more detail, as mentioned above, the module case 120 of the battery module 100 may include an upper module case 121. Referring to Figure 5, the upper module case 121 may have an exhaust hole 125 through which flames or gases are discharged. The exhaust hole 125 can then be connected to the discharge path 211 of the pack case 200 in various ways.

[0059] For example, referring to Figures 4, 5, and 6, the discharge hole 125 formed in the upper module case 121 and the connecting hole 212 formed in the upper frame 210 are in communication with each other and can be connected by a connecting portion 300.

[0060] In other words, the connecting part 300 connects the discharge hole 125 and the connecting hole 212, thereby connecting the discharge hole 125 and the discharge path 211, and allowing the flame or gas to move through the connecting part 300 to the discharge path 211.

[0061] The connecting portion 300 can be configured in various ways. For example, it may be composed of a gasket or sealing member to prevent leakage of flame or gas. In this case, the connecting portion 300 performs the function of sealing to prevent leakage of flame or gas, as well as connecting the discharge hole 125 and the connecting hole 212. However, it is not limited to this, and the connecting portion 300 may be made from various materials and configured to form a connecting passage through which flame or gas can move.

[0062] Referring to Figure 4, flames or gases generated from the battery cells 110 inside the battery module 100 are discharged to the outside of the module case 120 through the discharge hole 125 and move to the discharge path 211 inside the upper frame 210 of the pack case 200 through the connecting part 300 that connects the discharge hole 125 and the connecting hole 212.

[0063] As mentioned above, since a hollow discharge path 211 is formed inside the upper frame 210, flames or gases that have moved into the upper frame 210 through the connecting portion 300 and the connecting hole 212 can move along the discharge path 211 inside the upper frame 210 and be discharged.

[0064] With this method, if a flame is generated from any one of the battery cells 110, the flame inside the battery pack 10 and the heat from the flame are uniformly diffused along the exhaust path 211 inside the upper frame 210, thereby preventing heat concentration or trapping of thermal energy and ensuring a uniform heat distribution.

[0065] Furthermore, the venting through the discharge path 211 of the upper frame 210 becomes smoother, allowing gas to be easily discharged.

[0066] Furthermore, it can prevent thermal runaway phenomena by preventing a chain reaction of flames caused by flame propagation.

[0067] Referring to Figure 3, the lower frame 220 is configured to accommodate multiple battery modules 100. The lower frame 220 may, but is not limited to, be formed in the shape of a rectangular plate. The lower frame 220 forms the bottom of the pack case 200.

[0068] The side frame 230 may be configured to extend upward from the edge of the lower frame 220. The side frame 230 defines the height of the pack case 200 and forms a predetermined space between it and the lower frame 220.

[0069] Multiple battery modules 100 are then mounted in the space between the side frame 230 and the lower frame 220. The side frame 230 may include a long-side side frame with a relatively long length and a short-side side frame with a relatively short length. Alternatively, all of the side frames 230 may be of the same length.

[0070] The bulkhead frame 240 extends upward within the lower frame 220 and connects to the side frame 230. One or more bulkhead frames 240 are provided, and battery modules 100 can be positioned between multiple bulkhead frames 240, or between the bulkhead frames 240 and the side frame 230. Here, the bulkhead frames 240 can be arranged laterally or vertically within the side frame 230.

[0071] Figure 7 is a cross-sectional view of a battery pack according to a second embodiment of the present invention, and Figure 8 is a cross-sectional view of a battery pack according to a third embodiment of the present invention.

[0072] The second and third embodiments of the present invention differ from the first embodiment in that they are equipped with backflow prevention members 400. However, for parts of the second or third embodiment that are common with those described in the first embodiment, the description of the first embodiment above will be used instead. Also, for parts of the second or third embodiment that are applicable to the first embodiment, they may be applied to the first embodiment.

[0073] The backflow prevention member 400 is provided inside the upper frame 210 to prevent backflow of flame or gas. Here, the backflow prevention member 400 can be configured in various ways. For example, it may be configured to rotate in response to the flame or gas, but is not limited to this.

[0074] Referring to Figure 7, the backflow prevention member 400 may include a pivot shaft 410 and a first opening / closing section 420. The pivot shaft 410 may be coupled to the upper surface inside the upper frame 210. The first opening / closing section 420 is rotatably coupled to the pivot shaft 410 and contacts the lower surface of the upper frame 210. The first opening / closing section 420 may be configured to contact the upper frame 210 to the lower left of the pivot shaft 410, as shown in Figure 7, but is not limited to this and can be modified depending on the direction of gas movement.

[0075] Referring to Figure 7, when the gas moves from right to left (see arrow) relative to Figure 7, the first opening / closing section 420 rotates around the pivot shaft 410 and opens. The gas can then be discharged moving from right to left. However, after the gas has passed through the first opening / closing section 420, the first opening / closing section 420 rotates due to gravity and closes, thus preventing the gas from moving in the reverse direction.

[0076] Referring to Figure 8, the backflow prevention member 400 may include a projection 430, an elastic portion 440, and a second opening / closing portion 450.

[0077] The projection 430 protrudes from the upper frame 210. For example, the projection 430 includes a first projection 431 and a second projection 432, the first projection 431 protruding from the upper surface of the upper frame 210 and the second projection 432 protruding from the lower surface of the upper frame 210. Here, the second projection 432 may be configured to be spaced apart from the first projection 431 at a predetermined distance at a position corresponding to the position of the first projection 431.

[0078] The elastic portion 440 is then coupled to the projection 430. The elastic portion 440 includes a first elastic portion 441 and a second elastic portion 442, the first elastic portion 441 may be coupled to the first projection 431, and the second elastic portion 442 may be coupled to the second projection 432.

[0079] The second opening / closing section 450 is then connected to the elastic section 440, that is, to the first elastic section 441 and the second elastic section 442, respectively, as shown in Figure 8.

[0080] In this structure, when gas moves from right to left (see arrow) relative to Figure 8, the second opening / closing section 450 opens. The gas can then be discharged by moving from right to left relative to Figure 8 along the direction of the arrow. However, after the gas has passed through the second opening / closing section 450, the second opening / closing section 450 is closed by the elastic force of the elastic section 440, thus preventing the gas from moving in the reverse direction.

[0081] Figure 9 is a plan view of a portion of a battery pack according to the fourth embodiment of the present invention. Figure 10 is a plan view of a portion of a battery pack according to the fifth embodiment of the present invention.

[0082] The fourth and fifth embodiments of the present invention differ from the other embodiments in that they include a path expansion member 500. However, the parts of the fourth or fifth embodiment that are common with the parts described in the other embodiments will be described in the preceding explanation. Also, the parts of the fourth or fifth embodiment that are applicable to the other embodiments may be applied to the other embodiments.

[0083] The path expansion member 500 is provided in a cavity inside the upper frame 210 to expand the exhaust path for flame or gas. That is, the path expansion member 500 lengthens the travel path for flame or gas, allowing the flame or hot gas (or hot spark, etc.) to cool down or extinguish as it travels.

[0084] Referring to Figure 9, the path extension member 500 may include at least one first projection 510 and at least one second projection 520. Here, at least one first projection 510 protrudes from a first portion of the upper frame 210, and at least one second projection 520 protrudes from a second portion of the upper frame 210.

[0085] Here, the first protrusion 510 and the second protrusion 520 are arranged alternately, and the effect is that the temperature decreases as the flame or gas moves in a zigzag pattern between the first protrusion 510 and the second protrusion 520 (see arrow in Figure 9).

[0086] Referring to Figure 10, the path extension member 500 may include at least one first projection 510 and at least one second projection 520. Here, at least one first projection 510 protrudes from a first portion of the upper frame 210, and at least one second projection 520 protrudes from a second portion of the upper frame 210.

[0087] Here, the first projection 510 is positioned to be inclined toward the second portion, and the second projection 520 is positioned to be inclined toward the first portion. This has the effect of reducing the temperature as the flame or gas moves inclined between the first projection 510 and the second projection 520 (see arrow in Figure 10).

[0088] Figure 11 is a diagram illustrating an automobile including a battery pack according to each embodiment of the present invention.

[0089] Referring to Figure 11, an automobile 20 according to one embodiment of the present invention may include one or more battery packs 10 according to the embodiments described above. Here, the automobile 20 includes, for example, various automobiles that use electricity, such as electric vehicles and hybrid vehicles.

[0090] 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.

[0091] 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]

[0092] The present invention relates to a battery mod pack and an automobile containing the same, and is particularly applicable to the secondary battery industry.

Claims

1. Multiple battery modules, each consisting of multiple battery cells stacked on top of each other, The pack case includes the aforementioned multiple battery modules, At least a portion of the pack case has an exhaust path formed through which flames or gases generated in the battery cells are discharged. The aforementioned pack case includes an upper frame, The aforementioned discharge path is formed in the upper frame, To prevent backflow of flames or gases, the system includes a backflow prevention member provided on the upper frame, The aforementioned backflow prevention member is A projection protruding from the upper frame, The elastic part that is bonded, It includes a second opening / closing part connected to the elastic part, The aforementioned protrusion is A first projection protruding from the upper surface of the upper frame, It includes a second projection that protrudes from the lower surface of the upper frame at a position corresponding to the position of the first projection and is separated from the first projection by a predetermined distance, The elastic portion is A first elastic portion coupled to the first projection, A battery pack characterized by including a second elastic portion that is coupled to the second projection.

2. The battery pack according to claim 1, characterized in that the inside of the upper frame is hollow to allow flame or gas to move.

3. The upper frame has connecting holes formed therein. The battery pack according to claim 2, characterized in that the battery module is connected to the connecting hole.

4. The battery module includes the upper module case. The battery pack according to claim 1, characterized in that the upper module case has an exhaust hole formed therein through which flame or gas is discharged, and the exhaust hole is connected to the exhaust path of the pack case.

5. The battery pack according to claim 4, characterized in that it includes a connecting portion that connects the discharge hole and the discharge path.

6. The battery pack according to claim 5, characterized in that the connecting portion is made of a gasket or sealing member to prevent flame or gas leakage.

7. The battery pack according to claim 1, characterized in that it includes a path expansion member provided on the upper frame for expanding the flame or gas exhaust path.

8. The aforementioned path expansion member is At least one first projection protruding from the first portion of the upper frame, It includes at least one second projection protruding from the second portion of the upper frame, The battery pack according to claim 7, characterized in that the first protrusion and the second protrusion are arranged alternately.

9. The aforementioned path expansion member is At least one first projection protruding from the first portion of the upper frame, It includes at least one second projection protruding from the second portion of the upper frame, The first projection is arranged to be inclined toward the second portion. The battery pack according to claim 7, characterized in that the second protrusion is arranged to be inclined toward the first portion.

10. An automobile comprising at least one battery pack according to any one of claims 1 to 9.

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