Thermal runaway flue gas treatment system, battery pack assembly and electric vehicle

Abstract

The utility model provides a thermal runaway flue gas treatment system, a battery pack assembly and an electric vehicle, and mainly solves the problem that potential safety hazards exist in discharge of thermal runaway flue gas after thermal runaway of a battery pack of an existing electric vehicle. The thermal runaway flue gas treatment system comprises a cooling and filtering device and an ignition device, the cooling and filtering device cools and filters electrolyte and impurities in the thermal runaway flue gas before the thermal runaway flue gas is ignited by the ignition device, and when the treated thermal runaway flue gas enters the ignition device to be combusted, combustion flames are stable, and the combustion efficiency is improved. And the defects of flame splashing, flame instability and the like generated when electrolyte and impurities in the thermal runaway flue gas are combusted together with combustible gas are overcome. Meanwhile, after being cooled and filtered in the cooling and filtering device, the thermal runaway flue gas is discharged at a relatively stable flow speed, so that the potential safety hazards that the pressure of the thermal runaway flue gas is suddenly increased and the thermal runaway flue gas cannot be timely ignited are avoided, and the safety of the battery pack during use is improved.

Description

Technical Field

[0001] The utility model belongs to the field of electric vehicle battery safety, and particularly relates to a thermal runaway flue gas treatment system, a battery pack assembly and an electric vehicle. Background Technique

[0002] The battery pack is an important part of an electric vehicle, mainly providing driving power for the electric vehicle. In order to pursue higher endurance, multiple single cells are closely arranged in the box body of the battery pack. The high-density arrangement makes the safety and thermal stability of the battery pack poor. At the same time, under the influence of factors such as overcharging, over-discharging, overheating, and mechanical collision, it is easy to cause the battery diaphragm of each single cell in the battery pack to collapse and internal short circuit, resulting in thermal runaway of the battery pack. When the battery pack has a thermal runaway, a large amount of thermal runaway flue gas will be generated. After the high-temperature and high-pressure thermal runaway flue gas is discharged from the battery pack, it will pose a safety hazard. Summary of the Invention

[0003] In order to solve the problem that there is a safety hazard in the discharge of thermal runaway flue gas after the thermal runaway of the existing battery pack, the utility model provides a thermal runaway flue gas treatment system, a battery pack assembly and an electric vehicle.

[0004] To achieve the above object, the technical solution of the utility model is:

[0005] A thermal runaway flue gas treatment system for an electric vehicle battery pack, comprising a cooling and filtering device and an ignition device; the cooling and filtering device includes at least one cooling and filtering tank, the flue gas inlet of the cooling and filtering tank is used to connect with the explosion relief port of the electric vehicle battery pack, and the flue gas outlet is connected with the ignition device through a flue gas pipeline; the cooling and filtering tank is filled with a coolant, which is used to cool and filter the thermal runaway flue gas discharged from the electric vehicle battery pack; the ignition device is used to ignite the thermal runaway flue gas processed by the cooling and filtering tank.

[0006] Further, one-way valves are provided at both the flue gas inlet and the flue gas outlet of the cooling and filtering tank.

[0007] Further, a shunt pipe is provided in the cooling and filtering tank for shunting the thermal runaway flue gas entering the cooling and filtering tank.

[0008] Further, at least one layer of filter plate is provided in the cooling and filtering tank, and the filter plate is arranged above the outlet of the shunt pipe.

[0009] Further, the cooling and filtering tank is fixed on the box body of the battery pack through a bracket.

[0010] Further, the ignition device includes a housing, an ignition assembly, and a flame arrester; the flame arrester is connected to the housing and forms a combustion zone with the top plate of the housing; at least one flue gas passage communicating with the combustion zone is provided on the housing, and the flue gas passage is used to convey the thermally out-of-control flue gas in the flue gas pipeline to the combustion zone; the ignition assembly is used to ignite the thermally out-of-control flue gas in the combustion zone.

[0011] Further, the housing is provided with a plurality of flue gas passages, and the flue gas passages are through holes provided on the side wall of the housing and penetrating longitudinally along the housing. The plurality of flue gas passages are all communicated with the combustion zone and are used to dispersedly introduce the thermally out-of-control flue gas into the combustion zone.

[0012] Further, the flue gas passage includes a mixing passage and a first passage arranged in sequence. The mixing passage is communicated with the combustion zone, and an oxygen mixing port communicating with the external environment is provided on the mixing passage.

[0013] Further, an installation pipe is connected to the end of the flue gas pipeline. The installation pipe is sleeved on the housing and is connected to the housing by a thread; the ignition assembly includes a trigger and an igniter; the igniter includes an ignition needle, a high-voltage package, and a circuit board. The ignition needle is arranged in the combustion zone, the high-voltage package and the circuit board are integrated in the installation frame of the installation pipe, and the trigger is connected to the flue gas pipeline.

[0014] Further, the flame arrester includes a plurality of flame arrester mesh covers nested in sequence, and each flame arrester mesh cover is formed by metal wire weaving.

[0015] The present utility model also provides a battery pack assembly, including a battery pack and the above-mentioned thermally out-of-control flue gas treatment system; a pressure relief port is provided on the box body of the battery pack, and the pressure relief port is connected to the flue gas inlet of the cooling and filtering tank through a pressure relief pipeline.

[0016] The present utility model also provides an electric vehicle, including the above-mentioned battery pack assembly. The battery pack is arranged under the seat of the electric vehicle. The cooling and filtering device is fixed on the battery pack through a bracket or installed on the frame of the electric vehicle through a bracket, and the ignition device is fixed on one side of the rear wheel of the electric vehicle or above the rear wheel.

[0017] Compared with the prior art, the technical solution of the present utility model has the following advantages:

[0018] 1. The thermal runaway flue gas treatment system of the present utility model includes a cooling and filtering device and an ignition device. When any single battery in the battery pack undergoes thermal runaway, the cooling and filtering device and the ignition device can controllably treat the thermal runaway flue gas, avoiding potential safety hazards caused by the discharge of the thermal runaway flue gas. At the same time, before the thermal runaway flue gas is ignited by the ignition device, the cooling and filtering device cools the thermal runaway flue gas to reduce its temperature, thereby avoiding damage to the parts in the ignition device by the high-temperature thermal runaway flue gas. At the same time, the cooling and filtering device treats the electrolyte and impurities carried in the thermal runaway flue gas so that the treated thermal runaway flue gas is a gaseous substance. When the gaseous thermal runaway flue gas enters the ignition device for combustion, the combustion flame is relatively stable, avoiding defects such as flame splash and unstable flame when the electrolyte and impurities in the thermal runaway flue gas burn together with the combustible gas. At the same time, after being cooled and filtered in the cooling and filtering device, the thermal runaway flue gas is discharged at a relatively stable flow rate, avoiding potential safety hazards such as a sudden increase in the instantaneous pressure of the thermal runaway flue gas, the thermal runaway flue gas not being ignited in time, or the sudden increase in the combustion flame, and improving the safety of the battery pack during use.

[0019] 2. In the thermal runaway flue gas treatment system of the present utility model, check valves are provided at both the flue gas inlet and the flue gas outlet of the cooling and filtering tank. The two check valves prevent the coolant in the cooling and filtering tank from entering the battery pack and the ignition device, which may cause damage to the battery pack and the ignition device. At the same time, the two check valves also prevent the volatilization of the coolant in the cooling and filtering tank. Therefore, after the battery pack is used for a long time, the coolant in the cooling and filtering device can continuously maintain a better treatment effect.

[0020] 3. In the thermal runaway flue gas treatment system of the present utility model, a diversion pipe is provided in the cooling and filtering tank. The diversion pipe scatters and diverts the thermal runaway flue gas, and the diverted thermal runaway flue gas fully contacts the coolant in the cooling and filtering tank, thereby improving the treatment effect of the cooling and filtering tank and making the treatment of the thermal runaway flue gas more thorough.

[0021] 4. In the thermal runaway flue gas treatment system of the present utility model, at least one layer of filter plate is provided in the cooling and filtering tank. The filter plate treats the solid impurities in the thermal runaway flue gas from the battery pack, further improving the filtering effect of the cooling and filtering tank on the impurities in the thermal runaway flue gas.

[0022] 5. In the thermal runaway flue gas treatment system of the present utility model, the outer shell of the ignition device has a plurality of flue gas channels. The plurality of flue gas channels disperse the thermal runaway flue gas into the combustion area, and the thermal runaway flue gas is dispersed and ignited, which can effectively reduce the flame height when the thermal runaway flue gas burns, so as to control the combustion flame within a certain height range and improve the safety of the entire ignition device during use.

[0023] 6. In the thermal runaway flue gas treatment system of the present utility model, the flue gas passage is a through hole provided on the side wall of the outer casing and penetrating longitudinally along it. The flue gas passage with this structure is relatively simple to manufacture and process, and the outer shape of the outer casing is also relatively beautiful.

[0024] 7. In the thermal runaway flue gas treatment system of the present utility model, the flue gas passage includes a mixing passage and a first passage that are connected in sequence from top to bottom. The oxygen mixing port transports external air into the mixing passage, mixes it with the thermal runaway flue gas input from the first passage, and then transports it to the combustion area for combustion. This way of mixing thermal runaway flue gas and oxygen before ignition makes the combustion of thermal runaway flue gas more complete, and the height of the combustion flame is further reduced.

[0025] 8. In the thermal runaway flue gas treatment system of the present utility model, the flame arrester includes a plurality of flame arrestor mesh covers nested in sequence. This flame arrester can not only prevent the combustion flame from overflowing but also isolate the heat generated during combustion, thereby further improving the safety of the ignition device during use.

[0026] Other advantages, objectives, and features of the present utility model will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 Structural schematic of the thermal runaway flue gas treatment system in Embodiment 1 Figure 1 ;

[0029] Figure 2 Structural schematic of the cooling and filtering tank with a shunt pipe in Embodiment 1;

[0030] Figure 3 Explosion diagram of the thermal runaway flue gas treatment system in Embodiment 1;

[0031] Figure 4 Cross-sectional view of the ignition device in Embodiment 1;

[0032] Figure 5 Structural schematic of the thermal runaway flue gas treatment system in Embodiment 1 Figure 2 ;

[0033] Figure 6Schematic structural diagram of the cooling and filtering tank with a filter plate in Embodiment 1;

[0034] Figure 7 Schematic structure of the electric vehicle in Embodiment 3 Figure 1 ;

[0035] Figure 8 Schematic installation diagram of the battery pack assembly in the electric vehicle in Embodiment 3;

[0036] Figure 9 Schematic structure of the electric vehicle in Embodiment 3 Figure 2 。

[0037] Reference numerals: 1 - battery pack, 2 - cooling and filtering device, 3 - ignition device, 4 - flue gas pipeline, 5 - electric vehicle, 6 - pressure relief pipeline, 11 - box body, 12 - explosion vent, 21 - cooling and filtering tank, 22 - flue gas inlet, 23 - flue gas outlet, 24 - check valve, 25 - filter plate, 26 - shunt pipe, 27 - bracket, 31 - outer shell, 32 - combustion zone, 33 - ignition assembly, 34 - flame arrester, 311 - top plate, 312 - flue gas channel, 3121 - first channel, 3122 - mixing channel, 3123 - oxygen mixing port, 331 - ignition needle, 332 - high voltage pack, 333 - circuit board, 334 - dry battery, 335 - trigger, 41 - installation pipe, 42 - installation bracket, 51 - seat, 52 - rear wheel. Detailed implementation manners

[0038] To make the above objects, features, and advantages of the present utility model more obvious and understandable, the following provides a detailed description of the specific implementation manners of the present utility model with reference to the accompanying drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0039] In this specification, "other embodiments" that appear in different places do not all refer to the same embodiment, nor are they separate or selectively exclusive embodiments from other embodiments. In the description of this specification, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0040] In the description of this specification, unless otherwise clearly specified and defined, the term "connection" 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 directly connected, indirectly connected through an intermediate member, or the communication inside two components. For those of ordinary skill in the art, the specific meaning of the above terms in this application can be understood according to specific circumstances.

[0041] Meanwhile, in the description of the present utility model, it should be noted that the orientation or positional relationship indicated by terms such as "top, bottom, inner, and outer" is based on the orientation or positional relationship shown in the drawings. It is 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. Therefore, it should not be construed as a limitation to the present utility model.

[0042] The battery pack is an important part of an electric vehicle, mainly providing driving power for the electric vehicle. Existing battery packs generally include multiple single cells (the single cells can be existing single cylindrical cells, square shell cells, soft-pack cells, etc.) and a battery management system. The multiple single cells are connected in series, parallel, or in series-parallel to meet different capacity requirements of the battery pack. The battery management system is mainly used to maintain and manage each single cell to prevent phenomena such as overcharging and over-discharging. During the use of the above multiple single cells, or during overcharging, over-discharging, and mechanical collision, thermal runaway is likely to occur, generating thermal runaway flue gas. This thermal runaway flue gas accumulates outside the battery pack, posing a safety hazard.

[0043] Based on this, the present utility model provides a thermal runaway flue gas treatment system. The thermal runaway flue gas treatment system includes a cooling and filtering device and an ignition device. When any single cell in the battery pack has a thermal runaway, the cooling and filtering device and the ignition device can controllably treat the thermal runaway flue gas to avoid the safety hazard caused by the discharge of the thermal runaway flue gas.

[0044] Before the thermal runaway flue gas is ignited by the ignition device, the above cooling and filtering device cools the thermal runaway flue gas to reduce the temperature of the thermal runaway flue gas, thereby avoiding damage to the parts in the ignition device by the high-temperature thermal runaway flue gas. At the same time, the cooling and filtering device filters the electrolyte and impurities carried in the thermal runaway flue gas, so that the treated thermal runaway flue gas is a gaseous substance. When the gaseous thermal runaway flue gas enters the ignition device for combustion, the combustion flame is relatively stable, avoiding defects such as flame splash and unstable flame generated when the electrolyte and impurities in the thermal runaway flue gas burn together; in addition, after the thermal runaway flue gas is cooled and filtered in the cooling and filtering device, it is discharged at a relatively stable flow rate, avoiding the safety hazard of sudden increase in instantaneous pressure of the thermal runaway flue gas, the thermal runaway flue gas cannot be ignited in time, or the combustion flame suddenly becomes large, improving the safety of the battery pack during use.

[0045] Example 1

[0046] As Figures 1 to 6 shown, this embodiment provides a thermal runaway flue gas treatment system for an electric vehicle battery pack. The thermal runaway flue gas treatment system includes a cooling and filtering device 2 and an ignition device 3. The cooling and filtering device 2 is used to connect to the explosion relief port 12 of the battery pack 1 to cool and filter the thermal runaway flue gas discharged from the battery pack 1. The ignition device 3 is connected to the cooling and filtering device 2 to ignite the thermal runaway flue gas processed by the cooling and filtering device 2.

[0047] As Figure 1 、 Figure 2 、 Figure 5 and Figure 6 shown, the cooling and filtering device 2 in this embodiment includes at least one cooling and filtering tank 21. The number of cooling and filtering tanks 21 can be set according to the number and requirements of the single cells in the battery pack 1. Each cooling and filtering tank 21 is provided with a flue gas inlet 22 and a flue gas outlet 23. If there are multiple cooling and filtering tanks 21, the flue gas inlets 22 and flue gas outlets 23 of adjacent cooling and filtering tanks 21 can be connected in series through pipelines. After series connection, the flue gas inlet 22 of the first cooling and filtering tank 21 is connected to the explosion relief port 12 of the battery pack 1 through a pressure relief pipeline 6, and the flue gas outlet 23 of the last cooling and filtering tank 21 is connected to the ignition device 3 through a flue gas pipeline 4. In actual use, considering cost and installation space, generally one cooling and filtering tank 21 is the best. At this time, the flue gas inlet 22 of this cooling and filtering tank 21 is connected to the explosion relief port 12 of the battery pack 1 through a pressure relief pipeline 6, and the flue gas outlet 23 is connected to the ignition device 3 through a flue gas pipeline 4. The above-mentioned pressure relief pipeline 6 and flue gas pipeline 4 generally adopt high-temperature and corrosion-resistant metal pipelines. At the same time, for the convenience of installation, the pressure relief pipeline 6 and flue gas pipeline 4 are preferably metal bellows.

[0048] The shape of the cooling and filtering tank 21 in this embodiment is not limited and can be a rectangular tank body, a circular tank body, an oval tank body, etc. The circular tank body is preferably used, and the circular tank body has good pressure-bearing performance. Each cooling and filtering tank 21 is filled with a coolant, and the coolant is a liquid such as water, alkali solution, fluorinated liquid, etc. The coolant cools the thermal runaway flue gas discharged from the battery pack 1. At the same time, when the thermal runaway flue gas passes through the coolant, the electrolyte and impurities carried in the thermal runaway flue gas are filtered and retained in the coolant, which can effectively avoid problems such as flame splashing and flame overflow caused by the simultaneous combustion of the electrolyte and impurities with combustible gas. If the coolant is an alkali solution, the alkali solution can not only remove the solid impurities and electrolyte in the thermal runaway flue gas, but also adsorb part of the thermal runaway flue gas, so that the subsequent ignition device 3 can fully process the remaining thermal runaway flue gas.

[0049] When the flue gas inlets 22 and flue gas outlets 23 on each of the above cooling and filtering tanks 21 are specifically arranged, the flue gas inlet 22 is generally arranged at the bottom of the cooling and filtering tank 21. At this time, the thermally out-of-control flue gas can smoothly pass through the coolant, and then the coolant can fully treat the thermally out-of-control flue gas. The flue gas outlet 23 is generally arranged at the top of the cooling and filtering tank 21. At this time, the gas in the thermally out-of-control flue gas can smoothly discharge from the cooling and filtering tank 21. At the same time, the thermally out-of-control flue gas is not likely to carry the liquid and impurities in the cooling and filtering tank 21 out of the cooling and filtering tank 21.

[0050] As Figure 1 and Figure 6 shown, when the cooling and filtering tank 21 in this embodiment is specifically connected, check valves 24 are provided at both the flue gas inlet 22 and the flue gas outlet 23 of the cooling and filtering tank 21. The two check valves 24 prevent the coolant in the cooling and filtering tank 21 from flowing into the battery pack 1 and the ignition device 3, which may cause damage to the battery pack and the ignition device. At the same time, the two check valves 24 can seal the coolant in the cooling and filtering tank 21 to prevent the coolant from volatilizing. After the battery pack is used for a long time, the coolant in the cooling and filtering device can continuously maintain a better treatment effect. In addition, the check valve 24 at the flue gas outlet can ensure the flow direction of the thermally out-of-control flue gas and prevent the occurrence of backfire.

[0051] As Figure 2 shown, to further improve the treatment effect of the coolant on the thermally out-of-control flue gas, a flow dividing pipe 26 is provided in the cooling and filtering tank 21 in this embodiment. The inlet of the flow dividing pipe 26 is connected to the flue gas inlet 22, and the outlet is immersed in the coolant. A plurality of through holes are formed in the side wall of the flow dividing pipe 26, and the thermally out-of-control flue gas is dispersed in the coolant through the plurality of through holes on the flow dividing pipe 26. The flow dividing pipe 26 breaks up and diverts the thermally out-of-control flue gas. After the diversion, the thermally out-of-control flue gas fully contacts the coolant in the cooling and filtering tank 21, thereby improving the treatment effect of the cooling and filtering tank, and the treatment of the thermally out-of-control flue gas is more thorough.

[0052] As Figure 2 and Figure 6 shown. It should be noted that when there is a flow dividing pipe 26 in the cooling and filtering tank 21, the flue gas inlet 22 can be arranged at the top or the side wall of the cooling and filtering tank 21.

[0053] As Figure 6 shown, at least one layer of filter plate 25 can also be provided in the cooling and filtering tank 21. The filter plate 25 treats the electrolyte and solid impurities in the thermally out-of-control flue gas in the battery pack 1, further improving the treatment effect of the cooling and filtering tank 21. When the filter plate 25 is installed, the filter plate is arranged above the outlet of the flow dividing pipe and close to the flue gas outlet 23, and filters the thermally out-of-control flue gas when the thermally out-of-control flue gas discharges from the cooling and filtering tank 21.

[0054] As Figure 1As shown, when the above-mentioned cooling and filtering tank 21 is installed, it can be specifically fixed on the box body 11 of the battery pack 1 through the bracket 27. It can also be installed on the frame of the electric vehicle 5 through the bracket, and the installation can be specifically carried out according to the specific structures of the electric vehicle 5 and the battery pack 1.

[0055] Based on the above structure, the cooling and filtering tank 21 in this embodiment has the following functions:

[0056] First, when the thermal runaway flue gas passes through the cooling and filtering tank 21, the instantaneous pressure of the thermal runaway flue gas drops. When the subsequent ignition device 3 ignites, the flame is relatively stable; at the same time, it also avoids the potential safety hazard that the instantaneous pressure of the thermal runaway flue gas suddenly increases, and the thermal runaway flue gas cannot be ignited in time or the combustion flame suddenly becomes larger.

[0057] Second, filter the electrolyte and impurities carried in the thermal runaway flue gas so that the processed thermal runaway flue gas is a gaseous substance. When the gaseous thermal runaway flue gas enters the ignition device 3 for combustion, the combustion flame is relatively stable, avoiding defects such as flame splashing and unstable flame when the electrolyte and impurities in the thermal runaway flue gas burn together with the combustible gas, and improving the safety of the thermal runaway flue gas during combustion.

[0058] Third, cool the thermal runaway flue gas discharged from the battery pack 1, remove the high-temperature property of the thermal runaway flue gas, and avoid damage to the subsequent pipelines and the components in the ignition device 3 caused by the high-temperature thermal runaway flue gas.

[0059] In this embodiment, the flue gas outlet 23 of the cooling and filtering tank 21 is connected to the ignition device 3 through the flue gas pipeline 4. After the cooling and filtering tank 21 processes the thermal runaway flue gas, the ignition device 3 ignites the thermal runaway flue gas processed by the cooling and filtering tank 21.

[0060] As Figures 2 to 4 shown, the ignition device 3 in this embodiment mainly includes an outer shell 31, a flame arrester 34 and an ignition assembly 33; the flame arrester 34 is connected to the outer shell 31 and forms a combustion area 32 with the top plate 311 of the outer shell 31. The combustion area 32 provides a combustion space for the combustion of the thermal runaway flue gas; at least one flue gas channel 312 communicating with the combustion area 32 is provided on the outer shell 31, and the flue gas channel 312 conveys the thermal runaway flue gas into the combustion area 32; the ignition assembly 33 is used to ignite the thermal runaway flue gas in the combustion area 32.

[0061] In this embodiment, as Figure 4As shown in the figure, there are multiple flue gas channels 312, and the multiple flue gas channels 312 are all connected to the combustion zone 32, and are used to disperse and introduce the thermally runaway flue gas into the combustion zone 32. The multiple flue gas channels 312 disperse and introduce the thermally runaway flue gas into the combustion zone 32, and the thermally runaway flue gas is dispersed and burned in the combustion zone 32. Compared with a centralized single combustion point, the combustion flame of the dispersed combustion is relatively small, which can reduce the flame height when the thermally runaway flue gas burns, control the flame height of the thermally runaway flue gas combustion within a certain range, and improve the safety when the entire thermally runaway flue gas is ignited.

[0062] As Figure 3 and Figure 4 As shown in the figure, the outer casing 31 in this embodiment is a cylindrical structure with a top plate 311. The top plate 311 and the fire retardant cover 34 above the top plate 311 form a combustion zone 32. There are multiple flue gas channels 312 provided on the side wall of the outer casing 31. The flue gas channels 312 are through holes provided on the side wall of the outer casing 31 and longitudinally penetrating the outer casing 31. The multiple flue gas channels 312 penetrate along the longitudinal direction of the cylinder and are connected to the combustion zone 32 at the top of the outer casing 31. The above-mentioned flue gas channels 312 can be mainly realized in the following ways:

[0063] First, there are multiple ribs extending along the length direction provided on the side wall of the outer casing 31. The flue gas channels 312 are through holes provided on the ribs and longitudinally penetrating. During specific processing, since the flue gas channels 312 are processed on the ribs, the requirement for the side wall thickness of the outer casing 31 is relatively low;

[0064] Second, multiple through holes longitudinally penetrating are processed on the side wall of the outer casing 31 to form the flue gas channels 312; when processing the flue gas channels 312 with this structure, it is required that the side wall of the outer casing 31 has a certain thickness;

[0065] Among the above various structural forms, the second structure with relatively simple manufacturing and processing is preferably selected. During specific processing, the number of flue gas channels 312 is 4 to 10, preferably 5 to 6. The multiple flue gas channels 312 can be evenly distributed along the circumference of the outer casing 31, and are preferably arranged in a circular shape with the longitudinal axis of the outer casing 31 as the center. This setting makes multiple uniformly dispersed combustion points formed when the thermally runaway flue gas is ignited, and the combustion flame heights of the respective dispersed combustion points are relatively uniform.

[0066] As Figure 4As shown in the figure, to further reduce the flame height during the combustion of thermal runaway flue gas, the thermal runaway flue gas can be mixed with oxygen before ignition. At the same time, after mixing with oxygen, the combustion of the thermal runaway flue gas is more complete. Specifically, the above-mentioned flue gas passage 312 may include a first passage 3121 and a mixing passage 3122 that are connected in sequence. The mixing passage 3122 is connected to the combustion zone 32. The mixing passage 3122 is provided with an oxygen mixing port 3123 that communicates with the external environment. The oxygen mixing port 3123 transports external air into the mixing passage 3122, mixes it with the thermal runaway flue gas input from the first passage 3121, and then transports it to the combustion zone 32.

[0067] Preferably, the central axes of the first passage 3121 and the mixing passage 3122 are coaxial. The cross-sectional size of the first passage 3121 is smaller than that of the mixing passage 3122, and the length of the first passage 3121 is greater than that of the mixing passage 3122. This kind of setting can not only increase the size of the oxygen mixing port 3123 and ensure the oxygen mixing ratio of the thermal runaway flue gas. At the same time, since both the first passage 3121 and the mixing passage 3122 are structures similar to capillary tubes, the capillary tubes can increase the flow velocity of the thermal runaway flue gas, ensure better oxygen mixing of the thermal runaway flue gas, and better oxygen mixing makes the combustion of the thermal runaway flue gas more complete, reducing the generation of yellow fire and even achieving flameless combustion.

[0068] During actual processing, since the size of the mixing passage 3122 is larger than that of the first passage 3121, the preferred solution in this embodiment is that the first passage 3121 is formed by a through hole provided on the side wall of the outer casing 31; the mixing passage 3122 is formed by a through hole provided on the convex rib of the outer casing 31. This kind of structure can not only ensure the strength of the outer casing 31, but also increase the number of oxygen mixing ports 3123 by arranging the mixing passage 3122 on the convex rib.

[0069] As Figure 3 and Figure 4 shown, the above-mentioned outer casing 31 is connected to the cooling and filtering tank 21 through the flue gas pipeline 4 to realize the transportation of the thermal runaway flue gas. When connecting, the flue gas pipeline 4 is sleeved on the outer casing 31, and at this time, the size of the outer casing 31 and the size of the flue gas pipeline 4 need to be matched. During actual assembly, the pipe diameter size of the flue gas pipeline 4 is generally smaller than the size of the outer casing 31, and the two cannot be matched for installation. Therefore, at this time, an installation pipe 41 that matches the size of the outer casing 31 can be fixedly connected to the end of the flue gas pipeline 4. The installation pipe 41 is sleeved on the outer casing 31 and is threadedly connected to the outer casing 31.

[0070] As Figure 3 and Figure 4As shown, in this embodiment, the ignition assembly 33 mainly includes a trigger 335 and an igniter; the igniter is used to ignite the thermal runaway flue gas in the combustion zone 32. The above-mentioned igniter can be implemented with different structures. For example, an existing arc igniter or a resistance wire igniter can be used. In this embodiment, an arc igniter can be specifically used, and this arc igniter can be specifically powered by a dry battery 334 or by an external circuit. The above-mentioned arc igniter specifically includes an ignition needle 331, a high-voltage package 332, a circuit board 333, etc. During specific installation, the ignition needle 331 is installed in the combustion zone 32, and the high-voltage package 332 and the circuit board 333 are integrated together and installed outside the combustion zone 32 to avoid damage to them caused by the combustion flame or heat of the thermal runaway flue gas.

[0071] As Figure 3 shown, when the high-voltage package 332, the circuit board 333, and the dry battery 334 of the above-mentioned igniter are specifically installed, they can be integrally installed on the outer housing 31 or the mounting pipe 41. At this time, a mounting bracket 42 can be added to the outer housing 31 or the mounting pipe 41, and the high-voltage package 332, the circuit board 333, and the dry battery 334 are integrated in the mounting bracket 42. At this time, the ignition needle 331 passes through the top plate 311 of the outer housing 31 and is connected to the high-voltage package 332. This installation method can not only protect the high-voltage package 332, the circuit board 333, and the dry battery 334 from being damaged during use or transportation.

[0072] As Figure 5 and Figure 6 shown, in this embodiment, since the flue gas channel 312 is preferably provided on the side wall of the outer housing 31, at this time, the outer housing 31 can be processed into a hollow structure, and the high-voltage package 332, the circuit board 333, and the dry battery 334 of the above-mentioned igniter can be arranged in the inner cavity of the outer housing 31. This installation method can not only protect the high-voltage package 332, the circuit board 333, the dry battery 334, and the trigger 335 from being damaged during use or transportation when they are installed outside the outer housing 31, but also make full use of the internal space of the outer housing 31 to realize the integrated installation of various devices and reduce the installation space of the entire device.

[0073] The above trigger 335 is used to start the igniter when the thermal runaway flue gas passes through the outer housing 31 or the flue gas pipeline 4. The trigger 335 can specifically adopt a sensor. When the battery pack undergoes thermal runaway and generates thermal runaway flue gas, the sensor monitors the flow rate, pressure, temperature, gas composition, etc. of the thermal runaway flue gas in real time. When the monitored data exceeds the threshold, a signal is sent to the igniter to start ignition. The sensor in this embodiment can specifically adopt an air flow sensor, a flow sensor, a pressure sensor, a temperature sensor, etc. The air flow sensor can specifically adopt an e-cigarette microphone head, etc. When the trigger 335 is specifically installed, the air flow sensor is arranged at the bottom of the inner cavity of the outer housing 31, and can directly receive the direct impact trigger of the thermal runaway flue gas, ensuring that the igniter can be triggered in a timely and reliable manner after the battery undergoes thermal runaway. The flow sensor, pressure sensor or temperature sensor can be installed on the flue gas pipeline 4 to start the igniter in a timely manner when the thermal runaway flue gas passes through the flue gas pipeline 4.

[0074] In this embodiment, the flame arrester 34 forms a combustion zone 32 when the thermal runaway flue gas burns safely. The flame arrester 34 prevents the surrounding substances from being damaged by high temperature when the thermal runaway flue gas burns, and can also prevent rainwater from entering the igniter head. The flame arrester 34 can be implemented by the following structure:

[0075] First, the flame arrester 34 is a cylindrical structure with an open bottom. The side wall and the top of the cylinder are provided with air holes. To maintain aesthetics and installation convenience, the shape of the flame arrester 34 is preferably the same as that of the outer housing 31. The flame arrester 34 can prevent the flame from overflowing and isolate the heat generated during combustion;

[0076] Second, as Figure 4 shown, the flame arrester 34 includes a plurality of flame arrester wire meshes nested in sequence. Each flame arrester wire mesh is formed by weaving metal wires, specifically by weaving heat-insulating iron wire meshes; when the thermal runaway flue gas enters the combustion zone 32 and is ignited by the ignition assembly 33, a combustion flame will be generated. Under normal circumstances, the combustion flame has a relatively high combustion temperature, and the longer the combustion flame lasts, the higher the temperature, and it is very easy to burn through a single-layer flame arrester wire mesh. Therefore, two or more layers of flame arrester wire meshes are designed, which can ensure that the combustion flame burns inside the flame arrester wire mesh. The multi-layer flame arrester wire mesh can effectively reduce the probability that the high-temperature flame burns through the wire mesh and the flame overflows. In addition, the multi-layer flame arrester wire mesh can also isolate the heat generated when the thermal runaway flue gas burns, improving the safety of the device during use.

[0077] When the above flame arrester 34 is installed, it can be directly sleeved on the outside of the outer housing 31. At this time, an annular connecting boss is provided on the outside of the outer housing 31, and there is an external thread on the annular connecting boss. The inner wall of the flame arrester 34 has an internal thread, and the flame arrester 34 is connected to the annular connecting protrusion by a thread. Or, a connecting plate can also be provided at the open end of the bottom of the flame arrester 34, and the flame arrester 34 is fixed to the top plate 311 of the outer housing 31 through the connecting plate and bolts.

[0078] Example 2

[0079] As Figures 1 to 6 shown, this embodiment provides a battery pack assembly, which includes a battery pack 1 and a thermal runaway flue gas treatment system. An explosion vent 12 is provided on the box body 11 of the battery pack 1, and the explosion vent 12 is connected to the flue gas inlet 22 of the cooling and filtering tank 21 through a flue gas pipeline 4.

[0080] The battery pack 1 of this embodiment includes a box body 11 and battery modules arranged in the box body. The box body mainly integrally installs the battery modules and also provides safety protection for the battery modules, so that the battery modules are protected from impacts, vibrations, drops, etc. in the external environment. The shape and size of the box body can be designed according to the application scenario of the battery modules into shapes that are convenient for placement, such as cylinders, prisms, cubes, etc. In addition, to avoid the risk of short circuits between the battery modules in the box body and external devices, the above box body is generally made of insulating materials and materials with high stiffness.

[0081] The battery modules of the battery pack 1 mainly include a battery management system, wiring terminals, and multiple single cells. The multiple single cells are connected in series to meet different capacity requirements. The single cells can be existing single cylindrical cells, square shell cells, or soft pack cells. The battery modules are electrically connected to an external circuit or an electrical device through the wiring terminals. The wiring terminals can be arranged on the box body and exposed outside the box body for convenient charging and discharging. The battery management system (BMS) mainly monitors the working states of the single cells.

[0082] This embodiment adds a set of cooling and filtering device 2 and an ignition device 3 on the basis of the above battery pack. After the battery pack 1 undergoes thermal runaway, the thermal runaway flue gas first enters the cooling and filtering tank 21 for cooling and filtering to completely remove the electrolyte and solid impurities, and then triggers a sensor, and then the igniter starts to ignite the cooled and filtered thermal runaway flue gas.

[0083] When a one-way valve 24 is provided at the flue gas inlet 22 of the cooling and filtering tank 21, the explosion vent 12 on the box body 11 of the battery pack 1 is directly connected to the flue gas pipeline 4, and the explosion vent 12 is sealed through the one-way valve 24; if a one-way valve 24 is not provided at the flue gas inlet 22 of the cooling and filtering tank 21, a bursting part is provided on the explosion vent 12 on the box body 11 of the battery pack 1, and the bursting part can specifically be a bursting film or a bursting valve. At the same time, the installation height of the explosion vent is greater than the liquid level height of the coolant in the cooling and filtering tank 21 to prevent the liquid in the cooling and filtering tank 21 from entering the battery pack. If a one-way valve 24 is not provided at the flue gas outlet 23 of the cooling and filtering tank 21, at this time, the installation height of the ignition device 3 is greater than the liquid level height of the coolant in the cooling and filtering tank 21 to prevent the coolant in the cooling and filtering tank 21 from entering the ignition device 3.

[0084] Example 3

[0085] As Figures 7 to 9 shown, this embodiment provides an electric vehicle, and the electric vehicle 5 includes the battery pack assembly in Embodiment 2. The battery pack assembly is mounted on the vehicle body of the electric vehicle 5 and is used to supply power to the electrical devices of the electric vehicle 5.

[0086] During specific installation, as Figure 8 and Figure 9 shown, the battery pack 1 can be mounted under the seat 51 of the electric vehicle 5 or under the footrest. The cooling and filtering tank 21 can be fixed on the box body 11 of the battery pack 1 through the bracket 27 or can be mounted on the vehicle frame of the electric vehicle 5 through the bracket. The ignition device 3 is fixed on one side of the rear wheel 52 of the electric vehicle 5 or above the rear wheel 52.

[0087] In this embodiment, the cooling and filtering device 2 and the ignition device are integrated on the electric vehicle. When a thermal runaway occurs in the battery pack of the electric vehicle 5 and thermal runaway smoke is generated, the thermal runaway smoke enters the cooling and filtering device. After being processed in the cooling and filtering device, it enters the ignition device 3, and the ignition device 3 can perform a safe and controllable ignition treatment on the remaining thermal runaway smoke to reduce the safety hazards generated after the thermal runaway of the battery pack.

Claims

1. A thermal runaway flue gas treatment system for an electric vehicle battery pack, characterized in that: Including cooling and filtering device and ignition device; The cooling filter device comprises at least one cooling filter tank, the smoke inlet of the cooling filter tank is used to be connected to the explosion vent of the electric vehicle battery pack, and the smoke outlet is connected to the ignition device through the smoke pipeline; the cooling filter tank contains coolant for cooling and filtering the thermal runaway smoke discharged from the electric vehicle battery pack; The ignition device is used to ignite the thermal runaway flue gas after being treated by the cooling filter tank.

2. The thermal runaway flue gas treatment system according to claim 1, characterized in that: One-way valves are provided at the smoke inlet and the smoke outlet of the cooling filter tank.

3. The thermal runaway flue gas treatment system according to claim 1, characterized in that: A shunt pipe is provided in the cooling filter tank for shunting the thermal runaway flue gas entering the cooling filter tank.

4. The thermal runaway flue gas treatment system according to claim 3, characterized in that: At least one layer of filter plate is arranged in the cooling filter tank, and the filter plate is arranged above the outlet of the diversion pipe.

5. The thermal runaway flue gas treatment system according to claim 4, characterized in that: The cooling filter tank is fixed on the box body of the battery pack through a bracket.

6. The thermal runaway flue gas treatment system according to any one of claims 1 to 5, characterized in that: The ignition device comprises an outer shell, an ignition assembly and a flame arrester hood; the flame arrester hood is connected to the outer shell and forms a combustion zone with the top plate of the outer shell; the outer shell is provided with at least one smoke channel connected to the combustion zone, and the smoke channel is used to transport the thermal runaway smoke in the smoke pipeline to the combustion zone; the ignition assembly is used to ignite the thermal runaway smoke in the combustion zone.

7. The thermal runaway flue gas treatment system according to claim 6, characterized in that: The outer shell is provided with a plurality of smoke passages, which are through holes arranged on the side wall of the outer shell and extending longitudinally through the outer shell. The plurality of smoke passages are all connected to the combustion zone and are used to disperse the thermal runaway smoke into the combustion zone.

8. The thermal runaway flue gas treatment system according to claim 7, characterized in that: The flue gas channel comprises a mixing channel and a first channel which are arranged in sequence. The mixing channel is communicated with the combustion zone, and an oxygen mixing port which is communicated with the external environment is arranged on the mixing channel.

9. The thermal runaway flue gas treatment system according to claim 8, characterized in that: The end of the flue gas pipeline is connected with a mounting pipe, which is sleeved on the outer shell and connected to the outer shell by threads; The ignition assembly includes a trigger and an igniter; the igniter includes an ignition needle, a high-voltage package and a circuit board, the ignition needle is arranged in the combustion zone, the high-voltage package and the circuit board are integrated in the mounting frame of the mounting tube, and the trigger is connected to the flue gas pipeline.

10. The thermal runaway flue gas treatment system according to claim 6, characterized in that: The fire-blocking cover comprises a plurality of fire-blocking mesh covers which are nested in sequence, and each fire-blocking mesh cover is formed by weaving metal wires.

11. A battery pack assembly, characterized in that: It comprises a battery pack and a thermal runaway flue gas treatment system as claimed in any one of claims 1 to 10; an explosion vent is provided on the box of the battery pack, and the explosion vent is connected to the flue gas inlet of the cooling filter tank through a pressure relief pipeline.

12. An electric vehicle, characterized in that: It includes the battery pack assembly as described in claim 11, wherein the battery pack is arranged under the seat of the electric vehicle, the cooling filter device is fixed to the battery pack through a bracket, or is installed on the frame of the electric vehicle through a bracket, and the ignition device is fixed to one side of the rear wheel of the electric vehicle or fixed above the rear wheel.

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