Battery cell fire-proof and explosion-proof device and battery pack

Abstract

The utility model provides a fire-proof and explosion-proof device for a battery cell, which is applied to a plurality of blade battery cells which are arranged on the same side of a battery cell explosion-proof valve and are distributed in the same row, and comprises an isolating sheet which is adhered to the blade battery cells and is over against the battery cell explosion-proof valve, and a protective cover which is buckled above the isolating sheet, an isolation channel is formed by the isolation piece and the protective cover, and the isolation channel has a closed state that the isolation channel is only communicated with a fire-fighting liquid inlet; and the communication state is that the shell of the blade battery cell is communicated with the isolation channel when the battery cell explosion-proof valve is exploded. The thermal runaway management device has the effects of facilitating thermal runaway management of the battery pack and improving the use quality of the battery pack.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, in particular to a fire and explosion prevention device for battery cells, and the utility model also relates to a battery pack equipped with the fire and explosion prevention device for battery cells. Background Art

[0002] When the battery pack is abused, thermal runaway is likely to occur due to heat accumulation inside the battery pack. When a single battery cell undergoes thermal runaway, if it cannot be effectively controlled, it is extremely likely to trigger a fire, which will then spread among battery modules, battery packs, and even the entire battery compartment, thus causing a fire or even an explosion accident.

[0003] In related technologies, an in-box fire protection scheme is mostly adopted. The common in-box fire protection scheme usually uses aerosol or perfluoromethylhexanone. When the aerosol scheme is adopted, the aerosol is usually placed inside the battery pack. When the battery cells inside the battery pack undergo thermal runaway, although the aerosol can extinguish the fire, since a large amount of combustible gas is generated when the battery cells are burning, there is a possibility of re-ignition. When the perfluoromethylhexanone scheme is adopted, each battery pack needs to be equipped with a detector, pipeline solenoid valve, etc., which is costly and not conducive to the thermal runaway management of the battery pack. Summary of the Utility Model

[0004] In view of this, the utility model aims to provide a fire and explosion prevention device for battery cells, so as to facilitate the thermal runaway management of the battery pack and improve the use quality of the battery pack.

[0005] To achieve the above object, the technical solution of the utility model is realized as follows:

[0006] A fire and explosion prevention device for battery cells is applied to a plurality of blade battery cells distributed on the same side and in the same row of the explosion-proof valve of the battery cells. The device includes:

[0007] An isolation sheet attached to the blade battery cells and facing the explosion-proof valve of the battery cells, and a protective cover buckled above the isolation sheet;

[0008] The isolation sheet and the protective cover form an isolation channel, and the isolation channel has a closed state that only communicates with a fire protection liquid inlet; and has a communication state in which the housing of the blade battery cells is communicated with the isolation channel when the explosion-proof valve of the battery cells bursts.

[0009] Further, a notch is engraved on the isolation sheet at a position facing the explosion-proof valve of the battery cells.

[0010] Further, a front cross beam and a rear cross beam are respectively arranged at the front end and the rear end along the arrangement direction of the blade battery cells; both the front cross beam and the rear cross beam have cavities; the protective cover extends to the front cross beam and the rear cross beam;

[0011] Exhaust and liquid drainage windows are provided on both the front cross beam and the rear cross beam; the exhaust and liquid drainage windows communicate with the cavity and the isolation channel.

[0012] Further, an exhaust and liquid drainage valve communicating with the cavity is connected to the rear cross beam.

[0013] Further, the exhaust and liquid drainage valve is placed outside the upper shell of the battery pack.

[0014] Further, a middle cylinder is arranged between multiple blade cells; both ends of the middle cylinder are open, and an explosion-proof film is provided on the middle cylinder. When the pressure in the isolation channel increases, the explosion-proof film enables the middle cylinder to communicate with the isolation channel.

[0015] Further, the blade cells have one row or multiple rows;

[0016] The fire-fighting liquid inlet is communicated with a fire-fighting liquid inlet pipe.

[0017] Further, a temperature probe and / or a pressure sensor are connected to the top of the protective cover.

[0018] Compared with the prior art, the present utility model has the following advantages:

[0019] In the cell fire and explosion prevention device of the present utility model, an isolation channel is formed by arranging an isolation sheet and a protective cover above the cell explosion-proof valve; when the blade cells generate heat normally, the fire-fighting liquid entering the isolation channel from the fire-fighting liquid inlet fills the isolation channel; when the heat generation of the blade cells is abnormal, the air pressure in the blade cells increases, thereby detonating the cell explosion-proof valve. Under the action of the cell explosion-proof valve, the isolation sheet at the corresponding position is ejected, and then the fire-fighting liquid in the isolation channel fills into the blade cells with abnormal heat generation, achieving the effect of facilitating the management of thermal runaway of the battery pack and improving the use quality.

[0020] By providing a notch at the position of the isolation sheet facing the cell explosion-proof valve, when a certain blade cell malfunctions and causes the cell explosion-proof valve to burst, it is convenient to eject the isolation sheet at the corresponding position, achieving the effect of improving the feedback accuracy and ensuring the quality of the thermal runaway management of the battery pack.

[0021] By providing a front cross beam and a rear cross beam with cavities, and communicating the cavity with the isolation channel by opening exhaust and liquid drainage windows, the fire-fighting liquid capacity of this group of blade cells is increased; by connecting an exhaust and liquid drainage valve to the rear cross beam, when one or more blade cells have a thermal runaway and cause the pressure in the isolation channel to increase, the pressure causes the exhaust and liquid drainage valve to open, enabling the fire-fighting liquid in the isolation channel to flow out, and then facilitating more fire-fighting liquid to flow through the isolation channel to cool down or extinguish the blade cells.

[0022] By arranging the exhaust and drainage valve outside the upper shell of the battery pack, high-temperature fire-fighting liquid or flammable and explosive liquid is discharged outside the battery pack, reducing the impact of thermal runaway of a certain blade battery cell in the battery pack on the entire battery pack.

[0023] By arranging a middle cylinder with an explosion-proof sheet in the middle of the blade battery cells, when the pressure in the isolation channel increases, the explosion-proof sheet bursts into the middle cylinder. At this time, the fire-fighting liquid flows from both open ends of the middle cylinder into the battery pack, thereby realizing water fire-fighting for the whole battery pack and improving the overall safety of the battery pack.

[0024] By connecting a temperature probe and a pressure sensor to the top of the protective cover, it is convenient to monitor the temperature and pressure in the isolation channel. When a certain blade battery cell malfunctions due to use, it is convenient to send an alarm signal in advance, which is conducive to quickly troubleshooting problems.

[0025] The present utility model also provides a battery pack, including the above-mentioned battery cell fire and explosion protection device.

[0026] For the battery pack of the present utility model, by assembling the above-mentioned battery cell fire and explosion protection device, when the blade battery cells have thermal runaway, the fire-fighting liquid in the isolation channel can timely cool down or extinguish the blade battery, improving the use safety and quality of the battery pack.

[0027] By arranging a shell explosion-proof valve on the upper shell, when the overall pressure in the battery pack is too high, the shell explosion-proof valve bursts to discharge the high-temperature flammable gas in the battery pack, and at the same time facilitates the circulation of the fire-fighting liquid in the battery pack, improving the safety of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings forming a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0029] Figure 1 is a schematic diagram showing the arrangement of blade battery cells in an embodiment of the present utility model;

[0030] Figure 2 is a schematic diagram showing the fixing of the isolation sheet on the blade battery cells in an embodiment of the present utility model;

[0031] Figure 3 is a schematic diagram showing the protective cover in an embodiment of the present utility model;

[0032] Figure 4 is a partial cross-sectional view showing the isolation channel in an embodiment of the present utility model;

[0033] Figure 5 is a partial part schematic diagram showing the exhaust and drainage valve in an embodiment of the present utility model;

[0034] Figure 6 This is a schematic diagram showing the relative position between the exhaust and drainage valve and the upper shell in the embodiment of the present utility model;

[0035] Figure 7 This is a schematic diagram showing the fire-fighting liquid inlet and the fire-fighting liquid inlet pipe in the embodiment of the present utility model;

[0036] Figure 8 This is a schematic diagram showing the housing explosion-proof valve in the embodiment of the present utility model.

[0037] Description of reference numerals:

[0038] 1. Isolation sheet;

[0039] 101. Score mark;

[0040] 2. Protective cover;

[0041] 201. Temperature probe; 202. Pressure sensor;

[0042] 3. Isolation channel;

[0043] 4. Blade battery cell;

[0044] 401. Battery cell explosion-proof valve;

[0045] 5. Fire-fighting liquid inlet;

[0046] 6. Front crossbeam;

[0047] 7. Rear crossbeam;

[0048] 701. Exhaust and drainage valve;

[0049] 8. Cavity;

[0050] 9. Exhaust and drainage window;

[0051] 10. Middle cylinder;

[0052] 1001. Explosion-proof sheet;

[0053] 11. Fire-fighting liquid inlet pipe;

[0054] 12. Upper shell;

[0055] 1201. Housing explosion-proof valve;

[0056] 13. Bottom plate. Detailed implementation manners

[0057] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0058] In the description of the present utility model, it should be noted that if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "outer", etc. appear, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, if terms such as "first", "second", etc. appear, they are also only for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0059] In addition, in the description of the present utility model, unless otherwise clearly defined, the terms "installation", "connection", "connection", "connecting member" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in combination with specific situations.

[0060] The present utility model will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0061] Embodiment 1

[0062] This embodiment relates to a fire and explosion prevention device for battery cells, so as to facilitate the thermal runaway management of the battery pack and improve the use quality of the battery pack.

[0063] In terms of the overall structure, as Figures 1 to 8 shown, this fire and explosion prevention device for battery cells is applied to a plurality of blade batteries 4 distributed on the same side and in the same row as the explosion-proof valve 401 of the battery cell. The device includes: an isolation sheet 1 attached to the blade battery 4 and facing the explosion-proof valve 401 of the battery cell, and a protective cover 2 buckled above the isolation sheet 1; the isolation sheet 1 and the protective cover 2 form an isolation channel 3, and the isolation channel 3 has a closed state that only communicates with a fire liquid inlet 5; and has a communication state in which when the explosion-proof valve 401 of the battery cell explodes, the housing of the blade battery 4 communicates with the isolation channel 3.

[0064] By arranging the isolation sheet 1 and the protective cover 2 above the explosion-proof valve 401 of the battery cell to form the isolation channel 3; when the blade battery 4 generates heat normally, the fire liquid entering the isolation channel 3 from the fire liquid inlet 5 fills the isolation channel 3; when the heat generation of the blade battery 4 is abnormal, the air pressure inside the blade battery 4 increases, thereby detonating the explosion-proof valve 401 of the battery cell. Under the action of the explosion-proof valve 401, the isolation sheet 1 at the corresponding position is sprayed open, and then the fire liquid in the isolation channel 3 fills into the blade battery 4 with abnormal heat generation, achieving the effect of facilitating the thermal runaway management of the battery pack and improving the use quality.

[0065] Based on the above overall introduction, the separator 1 in this embodiment, as Figures 1 to 4 shown, is pasted above a plurality of blade-shaped battery cells 4 arranged in the thickness direction. The separator 1 is made of mica as the raw material. The fire inlet 5 is opened on the separator 1 or the protective cover 2, so that the fire inlet 5 is located at one end of the isolation channel 3, and it can realize filling the fire extinguishing liquid into the isolation channel 3 without affecting the assembly of the blade-shaped battery cells 4. When the blade-shaped battery cell 4 has a thermal runaway, the isolation channel 3 changes from a closed state to a connected state, and then the fire extinguishing liquid can be introduced into the shell of the blade-shaped battery cell 4. The fire extinguishing liquid can be a liquid with good fluidity and non-flammability. For example, water is selected as the fire extinguishing liquid in this embodiment.

[0066] Based on the purpose that when the blade-shaped battery cell 4 has a thermal disorder, the isolation channel 3 switches from a closed state to a connected state, in order to facilitate the separator 1 at the position corresponding to the blade-shaped battery cell 4 with thermal disorder to be easily blown open; a notch 101 is engraved on the separator 1 opposite to the cell explosion-proof valve 401. By opening the notch 101 at the position of the separator 1 opposite to the cell explosion-proof valve 401, when a certain blade-shaped battery cell 4 malfunctions and the cell explosion-proof valve 401 explodes, it is convenient to blow open the separator 1 at the corresponding position, achieving the effect of improving the feedback accuracy and ensuring the quality of the thermal runaway management of the battery pack.

[0067] When a single or multiple blade-shaped batteries have a thermal runaway, in order to increase the fire extinguishing liquid in the isolation channel 3, a front cross beam 6 and a rear cross beam 7 are respectively arranged at the front end and the rear end along the arrangement direction of the blade-shaped battery cells 4; both the front cross beam 6 and the rear cross beam 7 have cavities 8; the protective cover 2 extends to the front cross beam 6 and the rear cross beam 7; exhaust and drainage windows 9 are opened on both the front cross beam 6 and the rear cross beam 7; the exhaust and drainage windows 9 communicate the cavities 8 and the isolation channel 3. An exhaust and drainage valve 701 communicating with the cavity 8 is connected to the rear cross beam 7.

[0068] By arranging the front cross beam 6 and the rear cross beam 7 with cavities 8 and opening the exhaust and drainage windows 9 to communicate the cavities 8 with the isolation channel 3, the fire extinguishing liquid capacity of this group of blade-shaped battery cells 4 is increased; by connecting the exhaust and drainage valve 701 to the rear cross beam 7, when a single or multiple blade-shaped battery cells 4 have a thermal runaway and cause the pressure in the isolation channel 3 to increase, the pressure opens the exhaust and drainage valve 701, so that the fire extinguishing liquid in the isolation channel 3 flows out, and then it is convenient for more fire extinguishing liquid to flow through the isolation channel 3 to cool down or extinguish the fire of the blade-shaped battery cells 4.

[0069] It can be understood that when the exhaust and drainage windows 9 communicate the cavities 8 and the isolation channel 3, there can be various setting methods for the separator 1 and the protective cover 2. For example, in one method provided in this embodiment, the upper surfaces of the front cross beam 6 and the rear cross beam 7 are coplanar with the separator 1 fixed on the blade-shaped battery cells 4. At this time, the protective cover 2 extends to the front cross beam 6 and the rear cross beam 7 and is fixedly sealed with the front cross beam 6 and the rear cross beam 7.

[0070] Based on the purpose of increasing the fire extinguishing liquid flowing through the isolation channel 3 due to the exhaust and drainage valve 701 being connected to the rear crossbeam 7, as Figures 5 to 6 shown, in order to reduce the influence of the thermal runaway blade cell 4 on other cells; the exhaust and drainage valve 701 is placed outside the upper shell 12 of the battery pack. By setting the exhaust and drainage valve 701 outside the upper shell 12 of the battery pack, the high-temperature fire extinguishing liquid or flammable and explosive liquid is discharged outside the battery pack, reducing the influence of the thermal runaway of a certain blade cell 4 in the battery pack on the entire battery pack.

[0071] To facilitate the overall temperature adjustment of the battery pack, as Figures 7 to 8 shown, a middle cylinder 10 is provided between multiple blade cells 4; both ends of the middle cylinder 10 are open, and the middle cylinder 10 is provided with an explosion-proof film 1001. When the pressure in the isolation channel 3 increases, the explosion-proof film 1001 connects the middle cylinder 10 with the isolation channel 3. By setting the middle cylinder 10 with an explosion-proof film 1001 in the middle of the blade cell 4, when the pressure in the isolation channel 3 increases, the explosion-proof film 1001 explodes into the middle cylinder 10. At this time, the fire extinguishing liquid flows from the open ends at both ends of the middle cylinder 10 into the battery pack, thereby realizing water fire protection for the entire battery pack and improving the overall safety of the battery pack.

[0072] It can be understood that based on reducing the influence of a single or a certain blade cell 4 on all cells in the battery pack, the connection strength between the explosion-proof film 1001 and the middle cylinder 10 is set higher than that of the isolation film 1 with a notch 101, and higher than the strength of the exhaust and drainage valve 701. That is, when a certain blade cell 4 has a thermal runaway, the isolation film 1 at the corresponding position explodes first. When the pressure continues to increase, under the action of air pressure and water pressure, the exhaust and drainage valve 701 opens; when the pressure in the isolation channel 3 still continues to increase when the exhaust and drainage valve 701 is open, the explosion-proof film 1001 explodes. At this time, the fire extinguishing liquid fills the entire battery pack, adjusts the temperature of the battery pack and conducts water fire protection on the battery pack.

[0073] There are various connection methods between the isolation film 1 and the middle cylinder 10. For example, in an implementation manner provided in this embodiment, since the middle cylinder 10 is located between multiple blade cells 4, at this time, the isolation film 1 is fixed at other positions outside the middle cylinder 10, forming an avoidance of the middle cylinder 10; and the surface of the isolation film 1 fixed on the blade cell 4 is coplanar with the surface of the middle cylinder 10 connecting the explosion-proof film 1001.

[0074] The blade cell 4 has one row or multiple rows; the fire extinguishing liquid inlet 5 is connected to a fire extinguishing liquid inlet pipe 11. According to different volume requirements of the battery pack, the blade cell 4 can be set with one row or multiple rows. If multiple rows are set, the fire extinguishing liquid inlet pipe 11 is connected to multiple fire extinguishing liquid inlets 5. The number of pipes for introducing the fire extinguishing liquid into the battery pack is reduced.

[0075] To facilitate the monitoring of the air pressure or temperature in the isolation channel 3, a temperature probe 201 and / or a pressure sensor 202 are connected to the top of the protective cover 2. By connecting the temperature probe 201 and the pressure sensor 202 to the top of the protective cover 2, it is convenient to monitor the temperature and pressure in the isolation channel 3. When a certain blade cell 4 malfunctions due to use, an alarm signal can be sent in advance, which is conducive to quickly troubleshooting problems.

[0076] When the cell fire and explosion prevention device of this embodiment is in use, a fire-fighting liquid with a certain pressure is introduced into the isolation channel 3 through the fire-fighting liquid inlet pipe 11 from the fire-fighting liquid inlet 5. When the blade cell 4 generates heat normally, the fire-fighting liquid entering the isolation channel 3 from the fire-fighting liquid inlet 5 fills the isolation channel 3. However, when a certain blade cell 4 undergoes thermal runaway, the air pressure inside the blade cell 4 increases, thereby detonating the cell explosion-proof valve 401. The cell explosion-proof valve 401 explodes, and at this time, the isolation sheet 1 at the corresponding position of the blade cell 4 explodes from the notch 101, and the fire-fighting liquid flows into the blade cell 4. When the pressure in the isolation channel 3 still gradually increases, the exhaust and drainage valve 701 opens, thereby increasing the flow rate of the fire-fighting liquid in the isolation channel 3. When the pressure in the isolation channel 3 still increases, the explosion-proof sheet 1001 explodes, and the fire-fighting liquid enters the battery pack from the middle cylinder 10 to cool down and conduct water fire-fighting on the entire battery pack, which is convenient for the thermal runaway management of the battery pack and improves the use quality of the battery pack.

[0077] Embodiment 2

[0078] This embodiment relates to a battery pack, including the cell fire and explosion prevention device as above.

[0079] For the battery pack of the present utility model, by assembling the cell fire and explosion prevention device as above, when the blade cell 4 malfunctions thermally, the fire-fighting liquid in the isolation channel 3 can timely cool down or extinguish the blade battery, improving the use safety and quality of the battery pack.

[0080] As Figures 7 to 8 shown, the battery pack further includes an upper shell 12 and a bottom plate 13, and a group of blade cells 4 equipped with the cell fire and explosion prevention device are assembled in the battery pack housing formed by the upper shell 12 and the bottom plate 13. A housing explosion-proof valve 1201 is assembled on the upper shell 12.

[0081] By providing the housing explosion-proof valve 1201 on the upper shell 12, when the overall pressure in the battery pack is too high, the housing explosion-proof valve 1201 explodes to facilitate the discharge of the high-temperature and flammable gas in the battery pack, and at the same time facilitates the circulation of the fire-fighting liquid in the battery pack, improving the safety of the battery pack.

[0082] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A fire and explosion prevention device for a battery cell, applied to a plurality of blade battery cells distributed in the same row and on the same side of a battery cell explosion-proof valve, characterized in that: The device includes: An isolation sheet attached to the blade battery cell and facing the battery cell explosion-proof valve, and a protective cover buckled on the isolation sheet; The isolation sheet and the protective cover form an isolation channel, and the isolation channel has a closed state in which only a fire-fighting liquid inlet is connected; and has a connected state in which the shell of the blade battery cell is connected to the isolation channel when the battery cell explosion-proof valve explodes.

2. The battery core fire and explosion prevention device according to claim 1, characterized in that: A notch is carved on the isolation sheet at a position directly opposite to the battery core explosion-proof valve.

3. The battery core fire and explosion proof device according to claim 1, characterized in that: A front crossbeam and a rear crossbeam are respectively provided at the front end and the rear end along the arrangement direction of the blade cells; the front crossbeam and the rear crossbeam both have cavities; the protective cover extends to the front crossbeam and the rear crossbeam; The front crossbeam and the rear crossbeam are both provided with exhaust and drainage windows; the exhaust and drainage windows are connected with the cavity and the isolation channel.

4. The battery core fire and explosion proof device according to claim 3, characterized in that: The rear cross beam is connected with an exhaust and liquid discharge valve which is in communication with the cavity.

5. The battery core fire and explosion proof device according to claim 4, characterized in that: The exhaust and liquid discharge valve is arranged outside the upper shell of the battery pack.

6. The battery core fire and explosion proof device according to claim 1, characterized in that: A middle tube is arranged between the plurality of blade cells; the two ends of the middle tube are open, and an explosion-proof plate is provided on the middle tube, and when the pressure in the isolation channel increases, the explosion-proof plate enables the middle tube to communicate with the isolation channel.

7. The battery core fire and explosion proof device according to claim 1, characterized in that: The blade cells have one or more rows; The fire-fighting liquid inlet is connected with a fire-fighting liquid inlet pipe.

8. The battery core fire and explosion proof device according to any one of claims 1 to 7, characterized in that: The top of the protective cover is connected with a temperature probe and / or a pressure sensor.

9. A battery pack, characterized in that: The battery pack is provided with a battery cell fire and explosion prevention device as claimed in any one of claims 1 to 8.

10. The battery pack according to claim 9, characterized in that: The utility model comprises an upper shell, on which a shell explosion-proof valve is assembled.

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