Battery cell structure and vehicle including the same

Abstract

The present invention provides a battery cell structure in which, even if an existing vent hole is blocked, a vent region expands due to a fracture caused by an increased internal pressure, thereby being capable of discharging gas and preventing ejection of a material and a flame. A battery cell structure according to one aspect of the present invention comprises: a battery cell; a battery case, the battery case having an accommodation space configured to accommodate the battery cell therein and having an exhaust portion on at least one side thereof, the exhaust portion for exhausting gas generated by the battery cell; and a battery cover for covering the battery cell, in which the exhaust portion may include: an exhaust portion having an exhaust hole for exhausting the gas and a rupture portion ruptured when an internal pressure of the accommodation space is greater than or equal to a predetermined pressure; and a mesh portion, the mesh portion being positioned to face the accommodation space, and the discharge portion being positioned between the mesh portion and the accommodation space.

Description

Technical Field

[0001] The present disclosure relates to a battery cell structure and a vehicle including the battery cell structure, and more specifically, the present disclosure relates to a battery cell structure and a vehicle including the battery cell structure as follows: in the battery cell structure, even if the mesh portion is blocked by material generated by an event such as thermal runaway (for example, spark material including active materials and metals included in the electrode), the exhaust area will expand due to rupture caused by the increase in internal pressure, thereby exhausting gas and preventing the injection of material and flames.

[0002] This application claims priority to Korean Patent Application No. 10-2023-0020357 filed in Korea on February 15, 2023, the disclosure of which is incorporated herein by reference. Background Art

[0003] As the demand for portable electronic products such as laptop computers, camcorders, and mobile phones increases rapidly, and as the commercialization of robots and electric vehicles, etc. accelerates, active research on high-performance secondary batteries that can be repeatedly charged and discharged is being conducted.

[0004] Currently commercial secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries and lithium secondary batteries. Among them, lithium secondary batteries have attracted much attention due to their free charging and discharging with almost no memory effect, very low self-discharge rate and high energy density compared to nickel-based secondary batteries.

[0005] These lithium secondary batteries generally use lithium oxides and carbon materials as positive electrode active materials and negative electrode active materials, respectively. The lithium secondary battery includes: an electrode assembly in which a positive electrode plate and a negative electrode plate coated with positive electrode active materials and negative electrode active materials, respectively, are provided, wherein a separator is between the positive electrode plate and the negative electrode plate; and an outer shell (i.e., a battery case) that seals and stores the electrolyte and the electrode assembly together.

[0006] In addition, lithium secondary batteries may be classified into can-type secondary batteries in which an electrode assembly is accommodated in a metal can and pouch-type secondary batteries in which an electrode assembly is accommodated in a pouch of an aluminum laminate sheet according to the shape of a battery case.

[0007] Recently, secondary batteries have been widely used for driving and storing energy in electric vehicles and medium and large devices such as power storage systems (ESS) and small devices such as portable electronic devices. A plurality of secondary batteries can be electrically connected to each other and stored in a module housing to form a battery module, and these battery modules and / or battery cells can be electrically connected in a narrow space to increase energy density, thereby producing a battery pack.

[0008] However, if a large number of battery modules and / or battery cells are densely stored in a small space, they may be susceptible to accidents such as fire or explosion. Therefore, existing battery cell structures such as battery modules or battery packs have vents for discharging gas when an event such as thermal runaway occurs therein, and mesh members that prevent materials such as spark materials from being discharged during venting (the spark materials include active materials and metals included in electrodes).

[0009] However, the vent holes and the mesh member are clogged with materials generated when an event such as thermal runaway occurs, causing excessive internal pressure increase, thereby causing fire or explosion in the battery cell structure. Therefore, it is necessary to develop a new battery cell structure having a structure that solves the above problems. Summary of the invention

[0010] Technical issues

[0011] The present disclosure aims to solve the problems of the related art, and therefore the present disclosure aims to provide a battery cell structure, which is configured so that even if the vent hole is blocked by material generated by an event such as thermal runaway, the vent area will expand due to rupture caused by increased internal pressure, thereby exhausting gas and preventing the injection of material and flames.

[0012] However, the technical problems to be solved by the present disclosure are not limited to the above problems, and those skilled in the art will clearly understand other problems not mentioned above from the description of the present invention described below.

[0013] Technical Solution

[0014] According to one aspect of the present disclosure, a battery cell structure is provided, which includes: a battery cell; a battery case, the battery case having a storage space configured to store the battery cell therein and the battery case including a vent portion on at least one side thereof, the vent portion being configured to discharge gas generated from the battery cell; and a battery cover, the battery cover being configured to cover the battery cell, wherein the vent portion may include: a discharge portion, the discharge portion including a vent hole and a rupture portion, the vent hole being configured to discharge the gas, and the rupture portion being configured to rupture when the internal pressure of the storage space reaches a predetermined pressure or greater; and a mesh portion, the mesh portion being positioned facing the storage space, and the discharge portion being between the mesh portion and the storage space.

[0015] The exhaust hole may be configured to overlap with a portion of the mesh portion.

[0016] The rupture portion may be configured to overlap a portion of the mesh portion.

[0017] The mesh portion may be configured to discharge gas among materials generated during exhaust of the battery cell and prevent spark materials including metal and active materials included in an electrode from being discharged.

[0018] The rupture portion may be disposed adjacent to the exhaust hole.

[0019] The rupture portion may include a plurality of fragile portions configured to have a lower strength than surrounding portions.

[0020] The plurality of vulnerable portions may be formed along at least one straight line having a predetermined length.

[0021] The plurality of vulnerable portions may be formed to be spaced apart from each other by a predetermined distance.

[0022] The exhaust portion may include a guide portion configured to guide the gas from the exhaust hole to the mesh portion.

[0023] The guide portion may protrude from a circumference of the exhaust hole toward the mesh portion.

[0024] According to another aspect of the present disclosure, a vehicle including the battery unit structure according to the present disclosure is provided.

[0025] Beneficial Effects

[0026] According to one aspect of the present disclosure, in the battery cell structure, the venting area is preferably designed to be small initially and configured to expand by rupture when the mesh portion is blocked, thereby minimizing the inflow of oxygen and facilitating gas discharge.

[0027] According to another aspect of the present invention, even if the mesh member is blocked by spark material that may be generated by gas during exhaust, the exhaust area can be expanded by rupture to continuously and effectively exhaust gas and prevent the injection of spark material and / or flame.

[0028] However, effects obtainable from the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned above will be clearly understood by those skilled in the art from the description of the present invention described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the detailed description of the present invention, are used to provide further understanding of the technical concept of the present disclosure; therefore, the present disclosure is not to be construed as being limited to the accompanying drawings.

[0030] Figure 1 is a perspective view showing the appearance of a battery cell structure according to the present disclosure.

[0031] Figure 2 is an exploded perspective view showing a battery cell structure according to the present disclosure.

[0032] Figure 3 is a diagram illustrating a battery case included in a battery cell structure according to the present disclosure.

[0033] Figures 4 to 7 is a front view of a battery case included in a battery cell structure according to the present disclosure.

[0034] Figure 8 is a diagram illustrating a battery case included in a battery cell structure according to the present disclosure.

[0035] Fig. 9 As an example along the lines of Figure 8 Schematic cross-sectional view taken along line AA' in FIG.

[0036] Fig.10 is a diagram showing a vehicle according to the present disclosure. DETAILED DESCRIPTION

[0037] Below, the preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present disclosure and are used together with the detailed description of the present invention to provide a further understanding of the technical concept of the present disclosure. Therefore, the present disclosure is not to be construed as being limited to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same elements. In addition, in order to effectively explain the technical features of the present disclosure, the thickness, ratio and size of the elements in the accompanying drawings may be exaggerated.

[0038] It should be understood that the terms used in the specification and the appended claims should not be interpreted as limited to general and dictionary meanings, but should be interpreted based on the meanings and concepts corresponding to the technical aspects of the present disclosure based on the principle allowing the inventor to appropriately define the terms for the best interpretation.

[0039] Although terms indicating directions such as upward, downward, left, right, forward, and backward are used in this specification, it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the position of the target object or the position of the observer.

[0040] Therefore, the configurations proposed in the embodiments of this specification and the drawings only indicate the most preferred embodiments of the present disclosure, rather than representing all technical ideas of the present disclosure, and therefore it should be understood that various equivalents and modifications may be made thereto when the present application is filed.

[0041] Figure 1 is a perspective view showing the appearance of a battery cell structure according to the present disclosure. Figure 2 is an exploded perspective view showing a battery cell structure according to the present disclosure. Figure 3 is a diagram illustrating a battery case included in a battery cell structure according to the present disclosure.

[0042] Reference Figures 1 to 3 , a battery unit structure 2 according to the present disclosure may include a battery cell 10 , a battery case 20 and a battery cover 30 .

[0043] A plurality of battery cells 10 may be provided. The battery cell 10 may refer to a secondary battery. The battery cell 10 may include an electrode assembly, an electrolyte, a battery case containing the electrode assembly and the electrolyte, and a pair of electrode leads connected to the electrode assembly and extending outside the battery case. The battery cell 10 may be, for example, a pouch-type secondary battery. However, other types of secondary batteries (such as cylindrical batteries or prismatic batteries) may also be applied to the battery cell 10 in the present disclosure.

[0044] The battery case 20 may have a housing space 21 and a vent portion 22. The housing space 21 may be configured to accommodate the battery cell 10 therein. The vent portion 22 may be provided on at least one side of the battery case 20. The vent portion 22 may be configured to discharge the gas generated from the battery cell 10 to the outside of the battery case 20. The vent portion 22 may be provided at a position where the gas generated inside the battery cell structure 2 needs to be discharged. A plurality of vent portions 22 may be provided.

[0045] The battery cover 30 may be configured to cover the battery cell 10. The battery cover 30 may have a plate shape. The battery cover 30 may be coupled to the battery case 20 so as to cover the battery cell 10. The battery cover 30 may be coupled to the battery case 20 so as to cover the accommodation space 21. The coupling may be performed by bolting or welding.

[0046] Figure 4 and Figure 5 is a front view of a battery case included in a battery cell structure according to the present disclosure.

[0047] Reference Figure 4 and Figure 5 The exhaust portion 22 may include a discharge portion 220 and a mesh portion 230 .

[0048] The exhaust portion 220 may include an exhaust hole 221 and a rupture portion 222 .

[0049] The vent 221 may be configured to exhaust gas. The vent 221 may be configured in the form of a simple hole that passes through the battery housing 20. However, the vent 221 is not limited to a fully open hole. The vent 221 may be configured to be closed in a normal state, rather than fully open, and open according to changes in pressure or temperature. For example, the vent 221 may be a hole configured to open and close according to the pressure of the gas generated inside the battery housing 20 by applying a one-way valve.

[0050] The rupture portion 222 may be configured to rupture when the internal pressure of the accommodation space 21 reaches a predetermined pressure or more. The rupture portion 222 may be configured to have a lower strength than the surrounding portion. The rupture portion 222 may indicate a specific area configured to have a lower strength than the surrounding portion.

[0051] The mesh portion 230 may face the accommodation space 21, and the discharge portion 220 is between the mesh portion 230 and the accommodation space 21. The mesh portion 230 may be disposed on the outermost side of the battery case 20. The mesh portion 230 may be a mesh member disposed in each region corresponding to the vent hole 221 and the rupture portion 222. The mesh portion 230 may be configured to cover the entire region corresponding to the vent hole 221 and the rupture portion 222. The mesh portion 230 may have a plate shape disposed facing the discharge portion 220. The mesh portion 230 may be a member disposed separately from the discharge portion 220. The mesh portion 230 may include a mesh member disposed in each region corresponding to the vent hole 221 and the rupture portion 222. A predetermined space may be provided between the mesh portion 230 and the vent hole 221.

[0052] The mesh portion 230 may be configured to exhaust gas among materials generated during exhaust of the battery cell 10 and prevent spark materials including active materials and metals included in electrodes from being exhausted. The mesh portion 230 may be a mesh configured in a dense mesh.

[0053] The vent hole 221 may be configured to overlap a portion of the mesh portion 230. The vent hole 221 may be completely covered by the mesh portion 230. Except for the area overlapping the vent hole 221, at least a portion of the remaining area of ​​the mesh portion 230 may be configured to overlap the broken portion 222.

[0054] The rupture portion 222 may be configured to overlap a portion of the mesh portion 230. The rupture portion 222 may be completely covered by the mesh portion 230. Except for the area overlapping with the rupture portion 222, at least a portion of the remaining area of ​​the mesh portion 230 may be configured to overlap with the exhaust hole 221.

[0055] The above-mentioned battery cell structure 2 according to the present disclosure may be a battery module. The battery module may, for example, include a cell assembly (the cell assembly includes a plurality of battery cells 10 electrically connected to each other) and a module housing for accommodating the cell assembly. However, the battery cell structure 2 of the present disclosure is not limited thereto. The battery cell structure 2 may be a battery pack. Such a battery pack may be a battery pack manufactured by a cell-to-battery pack process without going through the process of manufacturing a battery module, and a battery pack including a plurality of battery modules. That is, the exhaust portion 22 according to the present disclosure may be disposed in a battery module housing and / or a battery pack housing.

[0056] If the exhaust hole 221 provided in the battery module housing and / or the battery pack housing is initially designed to be large to include an area corresponding to the ruptured portion 222, gas exhaust is easy but oxygen easily flows in from the outside, thereby increasing the risk of fire.

[0057] However, according to the structure of the present disclosure, the exhaust area may not be designed to be large at the beginning. If the mesh portion 230 is blocked, the exhaust area may be designed to expand by the rupture of the rupture portion 222, thereby solving the above-mentioned problem. In addition, in the case where spark materials and gases including metals and active materials included in the electrodes are generated due to an event such as thermal runaway inside the battery cell structure 2, even if the mesh portion 230 is blocked by spark materials that may be generated together with the gas during exhaust, the exhaust area may be expanded by the rupture of the rupture portion 222, thereby continuously and effectively exhausting the gas and preventing the ejection of spark materials and / or flames.

[0058] Return to reference Figure 5 , the rupture portion 222 may be disposed adjacent to the exhaust hole 221. According to this configuration, if the mesh portion 230 is clogged, the rupture portion 222 may be more easily ruptured by the gas advancing toward the exhaust hole 221.

[0059] Figure 6 and Figure 7 is a front view of a battery case included in a battery cell structure according to the present disclosure.

[0060] Reference Figure 6 and Figure 7 , the rupture portion 222 may include a plurality of vulnerable portions 222a.

[0061] The plurality of vulnerable portions 222a may be configured to have a lower strength than the surrounding portions. Each of the plurality of vulnerable portions 222a may be a region formed by a groove having a predetermined length to be thinner than the surrounding region. The plurality of vulnerable portions 222a may be formed along at least one straight line having a predetermined length. Figure 6, a plurality of vulnerable portions 222a may be formed along a straight line having a predetermined length in the X-axis direction. A plurality of vulnerable portions 222a may be formed to be spaced apart from each other by a predetermined distance. On the other hand, a plurality of vulnerable portions 222a may be formed continuously, rather than being spaced apart from each other.

[0062] On the other hand, the plurality of vulnerable portions 222a may be substantially formed as a closed loop, rather than the above-mentioned straight line. In this case, when rupture occurs along the plurality of vulnerable portions 222a, the exhaust holes may be respectively provided in the regions corresponding to the plurality of vulnerable portions 222a, so that the exhaust region may be expanded. Figure 7 As shown, in the case where the rupture portion 222 is configured to be connected to the exhaust hole 221, the plurality of vulnerable portions 222a may not form a completely closed loop. In this case, when rupture occurs along the plurality of vulnerable portions 222a, the region corresponding to the plurality of vulnerable portions 222a may be connected to the exhaust hole 221, so that the size of the exhaust hole may be increased, so that the exhaust region can be expanded.

[0063] According to this configuration of the present disclosure, rupture may easily occur along the plurality of vulnerable portions 222a. In addition, the battery cell structure 2 may be designed such that the venting region expands into a desired shape according to the arrangement positions and shapes of the plurality of vulnerable portions 222a.

[0064] Figure 8 is a diagram showing a battery case 20 included in a battery cell structure 2 according to the present disclosure. Fig. 9 As an example along the lines of Figure 8 Schematic cross-sectional view taken along line AA' in FIG.

[0065] Reference Figure 8 and Fig. 9 , the exhaust portion 22 may include a guide portion 223 .

[0066] The guide portion 223 may be configured to guide gas from the exhaust hole 221 to the mesh portion 230. The guide portion 223 may protrude from the periphery of the exhaust hole 221 toward the mesh portion 230. The guide portion 223 may extend from the outer end of the exhaust hole 221 to the mesh portion 230 (in the +Y axis direction).

[0067] According to the configuration of the present disclosure, the guide portion 223 may guide the air flow from the exhaust hole 221 to the mesh portion 230 , thereby facilitating the gas discharge.

[0068] Fig.10 is a diagram showing a vehicle 1 according to the present disclosure.

[0069] Reference Fig.10, the vehicle 1 may include a battery cell structure 2. The vehicle 1 may be a hybrid vehicle 1 or an electric vehicle 1. In addition to the battery cell structure 2, the vehicle 1 according to the present disclosure may further include various other components included in the vehicle 1. For example, in addition to the battery cell structure 2 according to the present disclosure, the vehicle 1 according to the present disclosure may further include a vehicle body, a motor, and a control device (such as an ECU (Electronic Control Unit)).

[0070] As described above, although the present disclosure has been described based on the preferred embodiments with reference to the accompanying drawings, it is clear to those skilled in the art that various and obvious modifications can be made according to this description without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should be interpreted by the claims as covering various modified examples.

[0071] [Description of Reference Numerals] 1: Vehicle

[0072] 2: Battery cell structure

[0073] 10: Battery Cell

[0074] 20: Unit structure housing 21: Accommodation space

[0075] 22: Exhaust part

[0076] 30: Battery cover

[0077] 220: Discharge part

[0078] 221: Exhaust hole

[0079] 222: Broken part

[0080] 222a: Multiple vulnerable parts 223: Guide part 230: Net part

Claims

1. A battery cell structure, comprising: Battery cells; a battery case having an accommodation space configured to accommodate the battery cell therein and including, on at least one side thereof, a vent portion configured to exhaust gas generated from the battery cell; as well as a battery cover, the battery cover being configured to cover the battery cell, Wherein, the exhaust part comprises: a discharge portion including a gas discharge hole configured to discharge the gas and a rupture portion configured to rupture when an internal pressure of the accommodation space reaches a predetermined pressure or more; and A mesh portion is positioned to face the accommodation space, and the discharge portion is between the mesh portion and the accommodation space.

2. The battery cell structure according to claim 1, in, The exhaust hole is configured to overlap with a portion of the mesh portion.

3. The battery cell structure according to claim 1, in, The rupture portion is configured to overlap with a portion of the mesh portion.

4. The battery cell structure according to claim 1, in, The mesh portion is configured to discharge gas among materials generated during exhaust of the battery cell and prevent spark materials including active materials and metals included in electrodes from being discharged.

5. The battery cell structure according to claim 1, in, The rupture portion is disposed adjacent to the exhaust hole.

6. The battery cell structure according to claim 1, in, The rupture portion includes a plurality of fragile portions configured to have a lower strength than surrounding portions.

7. The battery cell structure according to claim 6, wherein: The plurality of vulnerable portions are formed along at least one straight line having a predetermined length.

8. The battery cell structure according to claim 6, in, The plurality of vulnerable portions are formed to be spaced apart from each other by a predetermined distance.

9. The battery cell structure according to claim 1, in, The exhaust portion includes a guide portion configured to guide the gas from the exhaust hole to the mesh portion.

10. The battery cell structure according to claim 9, in, The guide portion protrudes from a peripheral edge of the exhaust hole toward the mesh portion.

11. A vehicle comprising the battery cell structure according to any one of claims 1 to 10.

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