Battery pack and vehicle

Abstract

The application relates to the technical field of batteries, in particular to a battery pack and a vehicle, the battery pack comprising: a cold plate; a plurality of battery cells, each of which is provided with a battery cell explosion-proof valve; a directional flow guide assembly spirally arranged on the side of a battery module and connected with the cold plate; a plurality of nozzles, which are arranged at intervals on the directional flow guide assembly, each of the nozzles being arranged towards one battery cell explosion-proof valve; a trigger assembly, the plurality of nozzles being connected with the trigger assembly; a shell; and a whole-pack explosion-proof valve arranged on the shell. The battery pack provided by the application can realize the combination of the battery module cooling and fire extinguishing functions, can spray the cooling liquid with the fire extinguishing function to the battery cell with thermal runaway in a targeted manner, realize the dual functions of directional cooling and heat resistance + global fire extinguishing / neutralization, reduce the thermal runaway spreading range, meanwhile, the battery pack can also treat and discharge the smoke generated by thermal runaway, so that the smoke sprayed through the whole-pack explosion-proof valve does not carry excessive toxic and harmful substances.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery pack and a vehicle. Background Technology

[0002] Currently, power batteries for new energy vehicles are widely used due to their high energy density and stable structure. However, extreme conditions such as abnormal charging and discharging, collisions, and short circuits can easily cause thermal runaway of the battery cells. After the explosion-proof valve ruptures, the release of high-temperature fumes, electrolyte vapors, and flammable substances may quickly ignite and spread, becoming a core safety bottleneck in the industry.

[0003] Existing power battery cooling systems rely solely on cold plates for daily heat dissipation, lacking fire extinguishing and gas neutralization functions, thus failing to address thermal runaway. Current fire extinguishing technologies often require independent extinguishing devices (fire extinguishing bombs, dry powder extinguishers, etc.), resulting in complex structures, large space requirements, high costs, and delayed response times. Furthermore, the coolant is often released in a generalized manner, making it difficult to extinguish open flames across the entire battery pack. Existing smoke treatment devices are often independently installed from the fire extinguishing system or involve adding complex purification structures outside the battery pack, but lack designs for coordinating coolant neutralization of harmful gases, allowing toxic fumes to easily spread after thermal runaway. In addition, existing solutions often require additional pumps, failing to fully utilize existing onboard components and the BMS system, further increasing the complexity and cost of the battery pack structure. Summary of the Invention

[0004] The purpose of this application is to provide a battery pack and vehicle that can, to some extent, solve the technical problem in the prior art where the power battery cooling system only achieves daily heat dissipation through a cold plate, lacks fire extinguishing and gas neutralization functions, and is difficult to deal with thermal runaway.

[0005] This application provides a battery pack, including: Cold plate; A battery module, comprising multiple battery cells, each of which is equipped with a cell explosion-proof valve; A directional drainage component is coiled on the side of the battery module and connected to the cold plate; The nozzles are multiple, and the number of nozzles is the same as the number of cell explosion-proof valves. The multiple nozzles are spaced apart on the directional drainage assembly, and each nozzle is oriented toward one of the cell explosion-proof valves. A triggering component, wherein the plurality of nozzles are respectively connected to the triggering component; The housing, the battery module, the directional drainage component, the plurality of nozzles and the triggering component are all disposed within the housing; A packaged explosion-proof valve, wherein the packaged explosion-proof valve is disposed in the housing.

[0006] In the above technical solution, the directional drainage component further includes: The manifold has a continuous bending structure; the cold plate is provided with a first connection port and a second connection port, one end of the manifold is connected to the first connection port, and the other end of the manifold is connected to the second connection port; The drainage branch pipes are multiple in number and are spaced apart from each other in the manifold, with each drainage branch pipe connected to the manifold. The number of drainage branches is the same as the number of nozzles, and each drainage branch is connected to one nozzle. In any of the above technical solutions, the nozzle further comprises: The main body is connected to the drainage branch pipe; A direct injection unit is disposed in the main body. The mist spraying section includes a plurality of atomizing nozzles, which are disposed on the main body and spaced apart circumferentially along the direct spraying section.

[0007] In any of the above technical solutions, the number of the packaged explosion-proof valves is at least one; the packaged explosion-proof valves include: A valve body for mounting to the housing; the valve body is provided with a discharge port facing the outside of the housing. A particulate trapping layer is disposed within the valve body; An adsorption layer is disposed within the valve body and is located between the particulate capture layer and the discharge port.

[0008] In any of the above technical solutions, the triggering component further includes: The detection unit is connected to the BMS in the battery pack. A control valve is connected to the BMS; the response time of the control valve is less than 50ms. The plurality of nozzles are respectively electrically or communicatively connected to the control valve.

[0009] In any of the above technical solutions, the triggering component further includes a control unit, the explosion-proof valve is provided with a cleaning unit, and the control unit is connected to the cleaning unit.

[0010] In any of the above technical solutions, the battery pack further includes a cooling circulation system connected to the cold plate to supply coolant to the cold plate.

[0011] In any of the above technical solutions, the coolant further comprises: a base liquid, an organic polymer fire extinguishing additive, a neutralizing component, and an adsorbent.

[0012] In any of the above technical solutions, the housing is further provided with a plurality of flow guides, the plurality of flow guides being located at the bottom of the battery module, and the coolant being able to flow to the outside of the housing through the flow guides; The cold plate is provided with a flow guide groove, which is connected to the flow guide section. This application also provides a vehicle that includes the battery pack described in any of the above technical solutions, and thus has all the beneficial technical effects of the battery pack, which will not be repeated here.

[0013] Compared with the prior art, the beneficial effects of this application are as follows: The battery pack provided in this application includes: a cold plate; a battery module comprising multiple battery cells, each battery cell being equipped with a cell explosion-proof valve; a directional drainage assembly, which is coiled on the side of the battery module and connected to the cold plate; multiple nozzles, the number of which is the same as the number of cell explosion-proof valves, the multiple nozzles being spaced apart on the directional drainage assembly, each nozzle facing one cell explosion-proof valve; a trigger assembly, the multiple nozzles being connected to the trigger assembly respectively; a housing, the battery module, the directional drainage assembly, the multiple nozzles, and the trigger assembly being disposed within the housing; and a whole-pack explosion-proof valve, the whole-pack explosion-proof valve being disposed within the housing.

[0014] The battery pack provided in this application can combine battery module cooling and fire extinguishing functions, and can also spray fire-extinguishing coolant on cells that have thermal runaway, achieving a dual effect of directional cooling and heat insulation + all-area fire extinguishing / neutralization, reducing the spread of thermal runaway. At the same time, this battery pack can also treat and discharge the smoke generated by thermal runaway, preventing the smoke discharged through the whole pack explosion-proof valve from carrying excessive toxic and harmful substances. The vehicle provided in this application includes the aforementioned battery pack. Therefore, the battery pack can effectively improve the safety of the vehicle, reduce the risk of large-scale thermal runaway of the battery pack leading to complete loss of the vehicle, and thus improve the safety of the occupants. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1This is an exploded structural diagram of the battery pack provided in an embodiment of this application; Figure 2 This is a partial structural schematic diagram of the battery pack provided in an embodiment of this application; Figure 3 A cross-sectional view of the explosion-proof valve of the battery pack provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of the explosion-proof valve for the battery pack provided in the embodiments of this application.

[0017] Figure label: 1-Shell; 2-Battery module; 3-Battery cell; 4-Battery cell explosion-proof valve; 5-Cold plate; 6-Main coolant channel; 7-Directional drainage assembly; 71-Diverter manifold; 72-Drainage branch pipe; 8-Nozzle; 81-Direct spray section; 82-Mist spray section; 83-Atomizing spray hole; 9-Trigger assembly; 91-Detection unit; 92-Control valve; 93-Control unit; 10-Cooling circulation system; 101-Coolant storage tank; 102-Cooling circulation pump; 103-Temperature sensor; 11-Whole package explosion-proof valve; 111-Particulate trap; 112-Activated carbon adsorption layer; 113-Discharge port; 114-Cover plate; 115-Perforated section; 116-Sealed connection section; 117-Elastic connector; 12-Guide groove; 13-BMS. Detailed Implementation

[0018] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0019] The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0020] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] The following reference Figures 1 to 4 The battery pack and vehicle described in the embodiments of this application are explained.

[0024] See Figures 1 to 4As shown, an embodiment of this application provides a battery pack, which includes: a cold plate 5, a battery module 2, a cell explosion-proof valve 4, a directional drainage assembly 7, a nozzle 8, a trigger assembly 9, a housing 1, and a whole-pack explosion-proof valve 11. The battery module 2, the cell explosion-proof valve 4, the directional drainage assembly 7, the nozzle 8, and the trigger assembly 9 are all disposed inside the housing 1. The battery module 2 includes multiple cells 3, which are arranged in an array inside the housing 1. Optionally, the number of cells 3 is at least 16. Each cell 3 includes a cell cover plate. The number of cell explosion-proof valves 4 is the same as the number of cells 3 and corresponds one-to-one. Each cell cover plate of each cell 3 has a cell explosion-proof valve 4 disposed at the center. Each cell explosion-proof valve 4 is located on the same side of the battery module 2. A directional flow guide assembly 7 is coiled on the side of the battery module 2 where the cell explosion-proof valves 4 are located, and the flow path of the directional flow guide assembly 7 covers all cell explosion-proof valves 4. The directional flow guide assembly 7 is connected and communicates with the cold plate 5, allowing the coolant in the cold plate 5 to flow into the directional flow guide assembly 7. There are multiple nozzles 8, the same number as the cell explosion-proof valves 4. These nozzles 8 are spaced apart on the directional flow guide assembly 7, with each nozzle 8 facing a cell explosion-proof valve 4, so that when a nozzle 8 is opened, it can spray coolant towards the corresponding cell explosion-proof valve 4. Triggering component 9 is located inside housing 1. Each nozzle 8 is connected to triggering component 9. When the temperature of a battery cell 3 becomes abnormal, triggering component 9 controls the opening of the nozzle 8 corresponding to the battery cell 3 to spray coolant onto the cell explosion-proof valve 4 of that battery cell 3. This achieves cooling and prevents fire, reducing the risk of thermal runaway propagation. If the battery cell 3 catches fire, spraying coolant onto it for cooling and initial fire suppression can also prolong the thermal runaway propagation rate, providing time for overall fire suppression. The overall explosion-proof valve 11 is located on one side wall of housing 1. The overall explosion-proof valve 11 serves as the overall flue gas outlet for the battery pack. When thermal runaway occurs inside the battery pack, the flue gas with a certain pressure and temperature is released through the overall explosion-proof valve 11. During the process of the flue gas flowing out through the overall explosion-proof valve 11, the valve can treat the flue gas, significantly filtering out toxic and harmful components. Optionally, the cell explosion-proof valve 4 is circular, preferably with a diameter of 12mm.

[0025] Specifically, the battery pack also includes a cooling circulation system 10, which is connected to the cold plate 5 to circulate coolant to the cold plate 5 and the directional drainage assembly 7. Optionally, the cooling circulation system 10 is disposed outside the housing 1 and fixed to the vehicle body using the battery pack. The housing 1 includes a mounting plate for the side panel, which is disposed at the bottom of the side panel. The battery module 2 is disposed inside the housing 1 on the mounting plate, and each cell has an explosion-proof valve 4 and a directional drainage assembly 7. The cooling circulation system 10 includes a coolant storage tank 101 and a cooling circulation pump 102. The coolant storage tank 101 is used to store coolant, and the cooling circulation pump 102 is connected to the coolant storage tank 101. The cold plate 5 is provided with an inlet and an outlet, which are respectively connected to the cooling circulation pump 102, so that the coolant can circulate between the coolant storage tank 101 and the cold plate 5 under the action of the cooling circulation pump 102.

[0026] Optionally, the cooling circulation pump 102 reuses the vehicle's original power battery cooling pump, eliminating the need for an additional independent pump body. Its power is directly controlled by the BMS13 to provide power for daily heat dissipation and emergency coolant supply. Optionally, the coolant storage tank 101 has a volume of 0.8L and stores the special composite coolant of this invention (conductivity 150μS / cm, latent heat of vaporization 2257kJ / kg). It reuses the vehicle's cooling circulation pump 102 (rated power 80W), and the temperature sensor 103 is located within the main coolant channel 6, with a measurement range of -40℃ to 300℃.

[0027] In this embodiment, the cold plate 5 is a stamped aluminum alloy liquid cooling plate 5, which is attached to the bottom of the battery module 2. It has an internal serpentine coolant main channel 6 that connects to the cooling circulation pump 102 for daily heat dissipation. The cold plate 5 has a reserved diversion interface for sealed connection with the directional flow guide assembly 7. Preferably, a temperature sensor 103 is installed in the coolant main channel 6 of the cold plate 5 to detect the coolant temperature in real time and feed it back to the BMS 13 for daily temperature regulation.

[0028] Furthermore, the coolant used in this embodiment contains fire extinguishing components and neutralizing components that can neutralize some components in the smoke. Specifically, the coolant includes: a base liquid, an organic polymer fire extinguishing additive, an alkaline neutralizing component, and an adsorbent. The base liquid is a common coolant used in battery packs in the prior art. The organic polymer fire extinguishing additive can be thermosensitive hydrogel, polyacrylamide, polyethylene oxide, superabsorbent polymer (SAP), xanthan gum, etc., which are common in the prior art. The neutralizing component can be other alkaline powders such as calcium hydroxide powder, magnesium oxide powder, and sodium hydroxide powder, all of which can undergo neutralization reactions with acidic toxic gases without changing the core function of the coolant. The adsorbent is modified activated carbon powder. Optionally, the composition ratio of the coolant in this embodiment is: 90% base coolant (ethylene glycol-water system), 5% organic polymer fire extinguishing additive, 3% calcium hydroxide powder, and 2% modified activated carbon powder. The conductivity at 25°C is ≤150μS / cm, and the high temperature resistance is ≥200°C. As can be seen, the battery pack provided in this embodiment uses a composite coolant formulation, which can achieve the following functions: Heat dissipation function: The ethylene glycol-water system achieves efficient heat conduction, and together with the serpentine channel of the cold plate 5, it removes the working heat of the battery cell 3 and maintains the temperature of the battery cell 3 at 25-45℃; Fire extinguishing function: Organic polymer additives capture high-energy free radicals during combustion, blocking the combustion chain reaction, and at the same time forming an aqueous film on the surface of combustibles to isolate oxygen; Neutralization function: After the calcium hydroxide powder is atomized with the coolant, it undergoes a neutralization reaction with the acidic and toxic gases such as hydrogen fluoride and hydrogen chloride generated by thermal runaway, producing harmless salts; Adsorption function: Modified activated carbon powder adsorbs harmful gases such as VOCs and carbon monoxide in flue gas, and together with the activated carbon in the whole package of explosion-proof valve 11, it achieves dual adsorption.

[0029] Optionally, vehicles using this battery pack also include a fan, which is located outside the battery pack and close to the explosion-proof valve 11 of the entire pack. When the explosion-proof valve 11 of the entire pack is opened, the fan is also turned on, which enhances the directional flow efficiency of airflow inside the battery pack and improves the exhaust efficiency of flue gas.

[0030] Furthermore, the directional drainage assembly 7 includes a manifold 71 and multiple drainage branches 72. The manifold 71 has a continuous bending structure. One end of the manifold 71 is provided with a first connector, and the other end of the manifold 71 is provided with a second connector. The cold plate 5 is provided with a first connection port and a second connection port. The first connector is connected to the first connection port, and the second connector is connected to the second connection port, so that the coolant in the cold plate 5 can flow into the manifold 71.

[0031] There are multiple drainage branch pipes 72, which are spaced apart on the manifold 71. The number of drainage branch pipes 72 is the same as the number of nozzles 8 and the number of cell explosion-proof valves 4, and they are set in a one-to-one correspondence. Each drainage branch pipe 72 is equipped with a nozzle 8, and the nozzle 8 is positioned directly opposite a cell explosion-proof valve 4. When the nozzle 8 is opened, it can spray coolant toward the corresponding cell explosion-proof valve 4.

[0032] Preferably, the manifold 71 is made of aluminum alloy and has 16 branch interfaces. Each branch pipe 72 is made of polytetrafluoroethylene and is covered with a ceramic composite strip (temperature resistant to over 1200°C). It extends along the side wall of the battery cell 3 to directly above the battery cell explosion-proof valve 4 and is connected to the nozzle 8 at the end.

[0033] Furthermore, the nozzle 8 includes a main body and a valve core. One end of the main body is connected to the drainage branch pipe 72, and the other end of the main body is the spray end, which is set towards the battery cell explosion-proof valve 4. The valve core is set inside the main body. The specific setting of the valve core and the main body can refer to the setting of a two-position solenoid valve. Multiple nozzles 8 are respectively electrically connected or communicatively connected to the trigger component 9. The trigger component 9 can control each nozzle 8 to open individually or partially at the same time.

[0034] The spray end is provided with a direct spray section 81 and a mist spray section 82 that are connected to the internal space of the main body. Preferably, the nozzle 8 is made of high temperature resistant electrical insulation material (polytetrafluoroethylene) and has an integral structure. It is divided into a direct spray section 81 and a surrounding mist spray section 82. The two parts have independent flow channels and are connected to the diversion branch pipe 72. Coolant is supplied synchronously.

[0035] The direct injection section 81 is centrally located and is used to spray coolant. Specifically, the direct injection section 81 is a cylindrical direct injection nozzle with an inner diameter preferably of 3-5mm. It is directly opposite the cell explosion-proof valve 4 and is 5-10mm away from the cell explosion-proof valve 4. It adopts a direct injection method, and the coolant is sprayed in a columnar shape onto the surface of the cell explosion-proof valve 4 and the top of the cell 3. By utilizing the efficient heat conduction and latent heat of vaporization of the coolant, it quickly absorbs the high temperature heat around the cell explosion-proof valve 4, reduces the temperature of the cell 3, prevents thermal runaway from spreading to the surrounding cells 3, and cools the cell explosion-proof valve 4 to prevent it from cracking due to continuous high temperature.

[0036] The misting section 82 includes multiple atomizing nozzles 83, which are spaced apart circumferentially along the direct spray section 81. The number of atomizing nozzles 83 is 8-12, arranged in a ring around the outside of the direct spray section 81. Preferably, the diameter of the atomizing nozzles 83 is 0.5-0.8 mm, and they are sprayed into the internal space of the battery pack at a 45° angle. The coolant forms micron-sized droplets after passing through the nozzles. The mist-like coolant quickly extinguishes open flames inside the battery pack. Simultaneously, the neutralizing components and adsorbents in the droplets diffuse with the airflow, neutralizing acidic toxic gases and adsorbing harmful organic gases within the pack, thus aiding in gas purification. In this embodiment, the nozzle 8 has both liquid spraying and mist spraying functions. It is made of stainless steel. The direct spray section 81 has an inner diameter of 4 mm and is 8 mm away from the cell explosion-proof valve 4. The surrounding misting section 82 has 10 atomizing nozzles 83 (0.6 mm diameter), spraying into the pack at a 45° angle.

[0037] Furthermore, the number of the packaged explosion-proof valve 11 is at least one. Preferably, in this embodiment, the number of packaged explosion-proof valves 11 is two, and the two packaged explosion-proof valves 11 have the same structure. The packaged explosion-proof valve 11 includes a valve body, which is disposed on one side wall of the housing 1. One end of the valve body is connected to the internal space of the housing 1, and the other end of the valve body is provided with a discharge port 113 for releasing the flue gas accumulated in the housing 1 after the thermal runaway of the battery cell 3.

[0038] The explosion-proof valve 11 also includes a cover plate 114, a fixing plate, and an elastic connector 117. The elastic connector 117 is specifically a spring. The cover plate 114 is provided with a sealing connection part 116, and the fixing plate is provided with a hollow part 115. The hollow part 115 can communicate with the internal space of the battery pack. There are multiple hollow parts 115, which are spaced apart circumferentially along the sealing connection part 116. The sealing connection part 116 is connected to the valve body. Under normal conditions, the cover plate 114 can seal each hollow part 115 to ensure the sealing performance of the explosion-proof valve 11. When thermal runaway occurs... After the flue gas flows through the perforated part 115, it rushes towards the cover plate 114, causing the cover plate 114 to move. The sealing connection part 116 moves a distance relative to the valve body, creating a gap between them. The elastic connector 117, which was originally in a compressed state, releases a certain length and abuts against the cover plate 114, keeping the cover plate 114 open relative to each perforated part 115. The cover plate 114 is provided with a connecting groove. Optionally, the connecting groove is annular and runs through both sides of the cover plate 114. The flue gas flows through each perforated part 115 and the connecting groove to the side of the cover plate 114 away from the internal space of the housing.

[0039] The explosion-proof valve 11 also includes a particulate trapping layer, specifically a honeycomb ceramic particulate trap 111 with a certain thickness of sheet-like structure, a specific filtration accuracy of 0.3μm, and a capture rate of 99.5%. Furthermore, the explosion-proof valve 11 also includes an adsorption layer, specifically an activated carbon adsorption layer 112 with a certain thickness of sheet-like structure, 25mm thick, and a specific surface area of ​​1000m² / g. The particulate trap 111 is positioned close to the inlet of the explosion-proof valve 11, and the adsorption layer is positioned between the particulate trapping layer and the discharge port 113, close to the discharge port 113. This allows the high-temperature flue gas generated after thermal runaway of the battery cell 3 to pass sequentially through the particulate trapping layer and the adsorption layer, significantly filtering out toxic and harmful components in the high-temperature flue gas.

[0040] Optionally, the particle capture layer can also be a metal fiber filter carrier with a filtration accuracy ≥0.3μm, achieving equally efficient particle capture. Furthermore, the metal fiber carrier is easier to regenerate at high temperatures. The adsorption layer can be made of activated carbon with high specific surface area, such as coconut shell activated carbon, coal-based activated carbon, or wood-based activated carbon, with an adsorption efficiency ≥90%, all capable of adsorbing toxic gases.

[0041] Furthermore, the packaged explosion-proof valve 11 also includes a cleaning device. A maintenance interface is provided on the side of the packaged explosion-proof valve 11, and the cleaning device is located at the maintenance interface. Specifically, the cleaning device can be a heating element or other device that can heat up the particle capture layer and adsorption layer. By heating up the particle capture layer and adsorption layer, impurities and dust on the particle capture layer and adsorption layer can be removed by heating and burning. Alternatively, the cleaning device can be a cleaning pipeline located at the maintenance interface, which removes impurities and dust on the particle capture layer and adsorption layer by rinsing. The packaged explosion-proof valve 11 is cleaned and maintained regularly by the cleaning device to prevent the packaged explosion-proof valve 11 from becoming blocked and unable to open normally. As can be seen, the explosion-proof valve 11 in this embodiment adopts the basic structure of the existing power battery pack explosion-proof valve. The particulate trap 111 and the activated carbon adsorption layer 112 are integrated in the internal flue gas channel and arranged sequentially along the flue gas flow direction without occupying additional battery pack space. The particulate trap 111 adopts a honeycomb ceramic filter carrier similar to the structure of diesel engine DPF, with a filtration accuracy of ≥0.3μm, capturing solid particles, dust, electrolyte combustion residue, etc. in the flue gas, with a capture rate of ≥99%. The activated carbon adsorption layer 112: uses high specific surface area coconut shell activated carbon, filled at the rear end of the particulate trap 111, with a thickness of 20-30mm, adsorbing toxic and harmful gases such as hydrogen fluoride, VOCs, and carbon monoxide that have not been neutralized by the coolant in the flue gas, with an adsorption efficiency of ≥90%.

[0042] Furthermore, the triggering component 9 includes a detection unit 91 and a control valve 92. The detection unit 91 includes a temperature detection sensor for detecting the overall temperature inside the battery pack and determining whether there is a risk of thermal runaway. The detection unit 91 and the control valve 92 are respectively connected to the BMS 13. The detection unit 91 can send the detection results to the BMS 13. The BMS 13 can determine which cell(s) 3 have experienced thermal runaway. The control valve 92 controls the nozzle 8 facing the corresponding cell 3 to open according to the judgment structure of the BMS 13. Alternatively, the number of detection units 91 is the same as the number of cells 3 and corresponds one-to-one. Each cell 3 is equipped with a detection unit 91 to detect the temperature of each cell 3. Each detection unit 91 is connected to the BMS 13 and can transmit the detection results to the BMS 13. The BMS 13 then transmits a command to the control valve 92 to open the corresponding nozzle 8, thereby spraying coolant and cooling spray onto the cell 3 that has experienced thermal runaway or has a risk of thermal runaway, reducing the risk and scope of thermal runaway propagation. As the control core of this battery pack, BMS13 integrates all functions including thermal runaway detection, alarm, component triggering, power regulation, and status monitoring, eliminating the need for an additional independent control unit 93, thus simplifying the system structure and improving response speed. Optionally, the number of detection units 91 is the same as the number of battery cells 3 and is set in a one-to-one correspondence. Preferably, the detection unit 91 also includes a smoke sensor. More preferably, the battery pack has two smoke concentration sensors. The temperature detection sensor, smoke sensor, and smoke concentration sensor are all electrically connected to the vehicle BMS13.

[0043] Preferably, the control valve 92 is a two-position two-way control valve 92, which is located near the interface between the manifold 71 and the first connection port to ensure a response time of ≤50ms, preferably 40ms.

[0044] Furthermore, the triggering component 9 also includes a control unit 93, which is electrically or communicatively connected to the cleaning device. Optionally, the control unit 93 is electrically or communicatively connected to the BMS13, and the control unit 93 is used to control the opening or closing of the cleaning device.

[0045] Furthermore, the mounting plate has multiple flow guides distributed in a grid pattern, and all flow guides correspond to and cover the spraying area of ​​each nozzle 8. The side of the cold plate 5 facing the mounting plate is provided with a flow guide groove 12, which can communicate with the flow guides. The bottom of the housing 1 or the cold plate 5 is also provided with a drain port. The coolant sprayed from the nozzle 8 flows out through each flow guide and then flows away along the flow guide groove 12. The coolant finally flows out through the drain port, thus avoiding accumulation in the battery pack.

[0046] Furthermore, the battery pack also includes a manually triggered valve, which is located on one side wall of the housing 1 and is connected to the control valve 92. When the detection unit 91 fails, the operator can manually trigger the valve to open the control valve 92, ensuring the reliability of the emergency function.

[0047] Furthermore, in the battery pack provided in this embodiment, the flow rate curve of nozzle 8 and the total cooling capacity have the following relationship to ensure that the coolant supply matches the heat generated by thermal runaway.

[0048] Specifically, based on the three core parameters of latent heat of vaporization of coolant (r), heat generated by thermal runaway of cell 3 (Q), and heat generated by thermal runaway of cell 3 (P), the total flow curve of nozzle 8 and the total amount of coolant used are calculated through the principle of thermal balance.

[0049] Wherein: Latent heat of vaporization r of the coolant: The latent heat of vaporization of the special coolant of this invention at 100℃ is 2257kJ / kg (measured value); Thermal runaway heat generation Q of cell 3: The total heat generation during the entire thermal runaway process of a single cell 3 is determined by the chemical system and capacity of cell 3. For example, Q of ternary lithium cell 3 (200Ah) is 800kJ (industry measured value). Thermal runaway power P(t) of cell 3: The curve of thermal runaway power of cell 3 changing with time. P(t)=dQ / dt. In the early stage of thermal runaway (0-10s), the thermal power rises rapidly to the peak value Pmax. In the middle stage (10-30s), Pmax is maintained. In the later stage (after 30s), it gradually decreases, showing a "peak-shaped" curve, such as 40kJ / s for ternary lithium cell 3.

[0050] (a) Calculation of instantaneous flow rate of a single nozzle with 8 nozzles During thermal runaway, the coolant needs to completely offset the heat generated by cell 3 through vaporization and sensible heat absorption. That is, the heat absorbed by the coolant per unit time is greater than or equal to the instantaneous heat generation power of cell 3, as shown in the formula: m(t)×(c×ΔT+r)≥P(t) in: m(t): Instantaneous coolant mass flow rate (kg / s) for a single nozzle; c: Specific heat capacity of the coolant; the coolant of this invention has c=3.5kJ / (kg·℃); ΔT: Coolant temperature rise, from room temperature (25℃) to vaporization temperature (100℃), ΔT = 75℃; P(t): Instantaneous heat generation power of cell 3 (kJ / s).

[0051] The instantaneous volumetric flow rate of a single nozzle (coolant density ρ = 1 kg / L) is derived as follows: V(t)=m(t)≥P(t) / (c×ΔT+r).

[0052] (ii) Flow curve of nozzle 8 Substituting the thermal runaway heat generation power curve P(t) of cell 3 into the above formula, we obtain the instantaneous volumetric flow rate curve V(t) of single nozzle 8, which is positively correlated with P(t): In the early stage of thermal runaway (0-10s): V(t) rises rapidly from 0 to the peak value Vmax, such as Vmax=0.016L / s (16mL / s). Mid-stage of thermal runaway (10-30s): V(t) is maintained at Vmax to ensure rapid cooling and fire suppression; In the later stage of thermal runaway (after 30s): V(t) gradually decreases with P(t) until the temperature of cell 3 drops below 80℃.

[0053] (III) Calculation of total coolant consumption The total coolant consumption for a single cell 3 is the integral of the flow rate curve over the entire thermal runaway process, and the formula is: V_total = 0t_endV(t)dt Where t_end is the thermal runaway end time (cell 3 temperature ≤ 80℃), for example, for ternary lithium cell 3 (200Ah) V_total = 0.5-0.8L / cell, the total coolant usage of the battery pack is the single cell usage × the number of cells 3, while reserving a 20%-30% margin to ensure fire extinguishing effect.

[0054] This battery pack has a single ternary lithium battery cell with a thermal runaway heat generation of Q=800kJ and a peak heat generation power of Pmax=40kJ / s. Calculations show that: The peak instantaneous flow rate of a single nozzle is Vmax = 0.016 L / s (16 mL / s). The total coolant usage per cell is V_total = 0.6L / cell, and the total coolant usage of the battery pack is 0.6 × 1.3 = 0.8L (with a 30% margin).

[0055] This battery pack has the following operating modes during use: Firstly, during the daily heat dissipation phase The vehicle BMS13 controls the cooling circulation pump 102 to operate at normal power. The special composite coolant circulates in the serpentine main channel of the cold plate 5, carrying away the working heat of the battery cell 3 through heat conduction. The temperature sensor 103 detects the coolant temperature in real time. When the temperature exceeds 45°C, the BMS13 increases the pump power to accelerate the coolant circulation and maintain the temperature of the battery cell 3 within a suitable range. At this time, the control valve 92 is in the closed state, there is no coolant flow in the directional diversion assembly 7 and the nozzle 8, the integrated explosion-proof valve 11 is in the normally closed state, and the flue gas treatment structure is on standby.

[0056] Secondly, the thermal runaway emergency phase When a battery cell 3 experiences initial thermal runaway, its temperature rises rapidly, and the explosion-proof valve is about to rupture. The system triggers the emergency procedure, which is centrally controlled by the vehicle's BMS13. All components work together, and the steps are as follows: 1. Signal detection and judgment: When the detection unit 91 around the cell explosion-proof valve 4 detects a temperature ≥150℃ or detects that the smoke / fume concentration exceeds the standard, it transmits the signal to BMS13 in real time. BMS13 immediately determines that it is the initial stage of thermal runaway, determines the location of the runaway cell 3, sends a thermal runaway alarm to the vehicle cab, and sends a trigger command to the control valve 92 and control unit 93. 2. Directional delivery of coolant: Control valve 92 opens rapidly within 50ms, BMS13 controls the cooling circulation pump 102 to increase to 1.5 times the rated power, and the special composite coolant in the cold plate 5 flows to the nozzle 8 through the manifold 71 and the branch pipe 72; 3. Nozzle 8 in operation: Nozzle 8 is activated for the runaway cell 3. Coolant is sprayed in a columnar shape through the direct spray section 81 of nozzle 8 to the cell explosion-proof valve 4, which quickly cools down and blocks heat diffusion. At the same time, micron-sized droplets are formed through the surrounding mist spray section 82, which cover the inside of the battery pack, extinguish open flames, and the neutralizing components in the droplets neutralize and adsorb the toxic gases in the entire pack with the adsorbent. 4. Precise coolant supply: Nozzle 8 supplies coolant according to the calculated flow curve until the temperature of cell 3 drops below 80°C. The total amount used does not exceed the calculated value. Excess coolant falls into the leak-proof guide section and is discharged from the battery pack through the drain interface to avoid accumulation and short circuit. 5. Smoke collection and purification: The smoke generated by thermal runaway flows naturally to the explosion-proof valve 11 of the whole pack under the pressure inside the battery pack. The smoke passes through the particulate trap 111 inside the explosion-proof valve to filter solid particles, and then through the activated carbon adsorption layer 112 to adsorb toxic gases. At the same time, the harmless gas neutralized by the coolant droplets mixes with the purified smoke and is discharged in compliance with the standards after passing through the explosion-proof valve of the whole pack. 6. System Restore Standby: Optionally, when BMS13 detects that the temperature of cell 3 is ≤80℃, it sends a stop command, the control valve 92 closes, the cooling circulation pump 102 resumes normal power, and the nozzle 8 stops supplying liquid; after the residual smoke in the battery pack is completely purified, the system returns to the normal heat dissipation stage.

[0057] The battery pack provided in this application, when one of the cells 3 experiences thermal runaway, triggers the system within 50ms. The nozzle 8 supplies coolant according to the flow curve, extinguishes the open flame of cell 3 within 30 seconds, and the temperature of cell 3 drops from 200℃ to below 80℃, effectively preventing heat diffusion to surrounding cells 3. The mist-like coolant neutralizes more than 85% of the hydrogen fluoride in the battery pack. Combined with the activated carbon in the explosion-proof valve 11 of the entire pack, the toxic gas adsorption rate is ≥90%. The particulate trap 111 captures 99.5% of solid particulate matter, and the purified flue gas fully complies with the GB / T 30484-2013 standard. The total coolant consumption in the entire process is 11.52L, with no waste. Excess coolant is discharged through the guide section, eliminating the risk of battery short circuit. The system has a fast response and good effect, and is fully suitable for vehicle application scenarios.

[0058] In summary, the battery pack provided in this application can combine cooling and fire extinguishing functions of the battery module 2, and can selectively spray fire-extinguishing coolant on the battery cell 3 that has thermal runaway, achieving a dual effect of directional cooling and heat insulation + all-area fire extinguishing / neutralization, reducing the spread of thermal runaway. At the same time, this battery pack can also treat and discharge the smoke generated by thermal runaway, preventing the smoke emitted through the whole pack explosion-proof valve 11 from carrying excessive amounts of toxic and harmful substances.

[0059] In addition, this battery pack has the following advantages: Scientific coolant supply and precise energy saving: Based on the latent heat of vaporization, heat generation and heat generation power, the nozzle 8 flow curve and total coolant consumption are calculated to achieve on-demand coolant supply, avoid waste, and ensure cooling and fire extinguishing effects. Compared with the traditional generalized coolant supply method, the coolant utilization rate is increased by more than 60%. Simplified structure and reduced cost: The vehicle-mounted pump body and BMS13 system are reused, eliminating the need for an additional independent power source and control unit 93; the flue gas treatment structure is integrated into the explosion-proof valve 11 of the whole pack, eliminating the need for complex external purification devices, reducing the internal space occupied by the battery pack by 40%, and reducing the overall production cost by more than 30%. Highly efficient and safe flue gas treatment: The explosion-proof valve 11 integrates a particulate trap 111 and activated carbon to achieve primary treatment of flue gas through "particulate filtration-gas adsorption". Combined with coolant mist neutralization, it removes toxic gases in two ways. The purified flue gas meets the "Safety Requirements for Recycling and Utilization of Power Batteries for New Energy Vehicles" (GB / T 30484-2013) standard, preventing the spread of toxic flue gas. 5. Strong adaptability and convenient maintenance: The device can be adapted to various existing power battery modules 2. The nozzle 8 and the diversion branch pipe 72 can be flexibly adjusted according to the size of the battery cell 3. The activated carbon in the whole package explosion-proof valve 11 can be replaced regularly through the maintenance interface. The particulate trap 111 can be self-cleaned by using the vehicle-mounted high-temperature regeneration function. The maintenance frequency is low and it is suitable for actual vehicle-mounted application scenarios. Multiple protections, no secondary hazards: The coolant uses a low conductivity formula (≤150μS / cm at 25℃), the drainage branch pipe 72 and nozzle 8 are made of high temperature resistant electrical insulation material, and the leakage prevention drainage part collects excess coolant to avoid coolant accumulation causing battery short circuit, thus eliminating secondary safety hazards from the source.

[0060] Embodiments of this application also provide a vehicle including the battery pack described in any of the above embodiments, thus possessing all the beneficial technical effects of the battery pack, which will not be repeated here.

[0061] By equipping this vehicle with the aforementioned battery pack, the safety of the vehicle can be effectively improved, reducing the risk of large-scale thermal runaway of the battery pack leading to complete loss of the vehicle, thereby improving the safety of the occupants.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A battery pack, characterized in that, include: Cold plate; A battery module, comprising multiple battery cells, each of which is equipped with a cell explosion-proof valve; A directional drainage component is coiled on the side of the battery module and connected to the cold plate; The nozzles are multiple, and the number of nozzles is the same as the number of cell explosion-proof valves. The multiple nozzles are spaced apart on the directional drainage assembly, and each nozzle is oriented toward one of the cell explosion-proof valves. A triggering component, wherein the plurality of nozzles are respectively connected to the triggering component; The housing, the battery module, the directional drainage component, the plurality of nozzles and the triggering component are all disposed within the housing; A packaged explosion-proof valve, wherein the packaged explosion-proof valve is disposed in the housing.

2. The battery pack according to claim 1, characterized in that, The targeted drainage component includes: The manifold has a continuous bending structure; the cold plate is provided with a first connection port and a second connection port, one end of the manifold is connected to the first connection port, and the other end of the manifold is connected to the second connection port; The drainage branch pipes are multiple in number and are spaced apart from each other in the manifold, with each drainage branch pipe connected to the manifold. The number of drainage branches is the same as the number of nozzles, and each drainage branch is connected to one nozzle.

3. The battery pack according to claim 2, characterized in that, The nozzle includes: The main body is connected to the drainage branch pipe; A direct injection unit is disposed in the main body. The mist spraying section includes a plurality of atomizing nozzles, which are disposed on the main body and spaced apart circumferentially along the direct spraying section.

4. The battery pack according to claim 1, characterized in that, The number of the packaged explosion-proof valves is at least one; the packaged explosion-proof valves include: A valve body for mounting to the housing; the valve body is provided with a discharge port facing the outside of the housing. A particulate trapping layer is disposed within the valve body; An adsorption layer is disposed within the valve body and is located between the particulate capture layer and the discharge port.

5. The battery pack according to claim 1, characterized in that, The triggering component includes: The detection unit is connected to the BMS in the battery pack. A control valve is connected to the BMS; the response time of the control valve is less than 50ms. The plurality of nozzles are respectively electrically or communicatively connected to the control valve.

6. The battery pack according to claim 5, characterized in that, The triggering component also includes a control unit, and the explosion-proof valve is equipped with a cleaning unit, with the control unit connected to the cleaning unit.

7. The battery pack according to any one of claims 1 to 6, characterized in that, The battery pack also includes a cooling circulation system connected to the cold plate to supply coolant to the cold plate.

8. The battery pack according to claim 7, characterized in that, The coolant comprises: a base liquid, organic polymer fire extinguishing additives, neutralizing components, and an adsorbent.

9. The battery pack according to claim 7, characterized in that, The housing is provided with multiple flow guides, which are located at the bottom of the battery module, allowing the coolant to flow to the outside of the housing via the flow guides. The cold plate is provided with a flow guide groove, which is connected to the flow guide section.

10. A vehicle, characterized in that, The battery pack includes any one of claims 1 to 9.

Images