Battery thermal runaway eradication method and system based on ultrahigh-activity chemical reaction

Abstract

The invention discloses a battery thermal runaway eradication method and system based on an ultrahigh-activity chemical reaction, and the method comprises the steps: 1, judging that a battery enters a thermal runaway initial stage based on a battery management system by fusing temperature, voltage, gas concentration and air pressure multi-sensor signals; 2, according to the type and capacity of the battery, calculating the actual dosage of the ultrahigh-activity chemical agent; 3, injecting the ultrahigh-activity chemical preparation with the dosage calculated in the step 2 into the battery in the initial stage of thermal runaway through a preset fusible sealed micro injection channel of the battery; and 4, carrying out a violent chemical reaction on the ultrahigh-activity chemical preparation and the electrolyte and / or the active electrode material in the battery, instantaneously consuming key reactants in the electrolyte, and converting the key reactants into stable and non-combustible solid products and / or gas-phase products, so that irreversible inactivation of the electrolyte is realized, and the thermal runaway chain reaction of the battery is terminated. According to the method, the chemical basis of continuous thermal runaway is fundamentally eliminated.

Description

Technical Field

[0001] This invention relates to the field of new energy battery technology, specifically to a method and system for eliminating battery thermal runaway based on ultra-high activity chemical reactions. Background Technology

[0002] Thermal runaway is the ultimate challenge in the field of battery safety. Existing technical solutions are mostly passive defenses or external interventions, such as heat insulation, phase change heat absorption, or spraying traditional fire extinguishing agents. These solutions have inherent defects such as slow response, difficulty in penetration, treating the symptoms but not the root cause, and high re-ignition rate. These solutions cannot effectively deal with the violent and continuous electrochemical exothermic reactions inside the battery.

[0003] For example, Chinese invention patent application number CN116864833 A discloses a battery thermal runaway control method, device, and storage medium. The battery thermal runaway control method includes: determining whether a battery pack has experienced thermal runaway; if a battery pack experiences thermal runaway, then controlling the battery pack cooling system to maintain operation after the start of thermal runaway and before the thermal runaway parameters of the battery pack reach the explosion threshold. This invention proposes a method that can control the battery pack cooling system to continuously cool the battery pack after thermal runaway occurs, which can slow down the continuous temperature rise caused by the battery pack's self-generated heat characteristics after thermal runaway, prolonging the time it takes for the battery pack temperature to rise to a dangerously high temperature, thereby increasing the response time of relevant control strategies for thermal runaway faults and improving the safety of battery pack use.

[0004] For example, Chinese invention patent application CN119481454 A discloses a lithium battery thermal runaway control system, including a battery box and a battery placed inside the battery box. The battery includes a top cover with a positive terminal and a negative terminal, a short-circuit mechanism, and a pull-wire mechanism to activate the short-circuit mechanism. It also includes a water-spraying mechanism and a temperature sensing system. The water-spraying mechanism's nozzle is aligned with a valve port, and the temperature monitoring mechanism detects the internal temperature of the battery and sends an operation command to the pull-wire mechanism. This structure and system, when detecting an abnormal temperature rise in a lithium battery within the box and determining that thermal runaway is imminent, drives the pull-wire mechanism to actively create an external short circuit in the lithium battery, rapidly depleting its charge. The water-spraying mechanism continuously cools the short-circuit structure by spraying water. This method can quickly and effectively control the thermal runaway of one or more lithium batteries, preventing spontaneous combustion of the lithium battery without affecting other batteries.

[0005] For example, Chinese invention patent application CN113022310A discloses a method and device for controlling thermal runaway of vehicle power batteries, relating to the fields of new energy vehicles and vehicle electronics technology. This method, to a certain extent, facilitates the improvement of the timeliness and effectiveness of controlling the risk of thermal runaway in power batteries. The method includes: acquiring mechanical quantity sensing signals of the power battery; the mechanical quantity sensing signals include at least two types; determining whether the power battery has a risk of thermal runaway based on the mechanical quantity sensing signals; if a risk of thermal runaway is determined to exist, then performing thermal runaway processing on the power battery based on a preset control strategy. This invention is applicable to the detection and control of thermal runaway risks in new energy vehicle power batteries.

[0006] The aforementioned existing technologies have not overcome the limitation of not intervening in the chemical root cause of thermal runaway. They only address the superficial symptoms of thermal runaway through physical means such as heat insulation, cooling, or external environmental control to suffocate or extinguish the fire. They cannot solve the core contradictions of continuous electrolyte decomposition and exothermic electrode materials, resulting in slow response, poor effectiveness, high reignition rate, and limited adaptability. Based on the above-mentioned technical problems of existing technologies, this invention provides a method and system for eliminating battery thermal runaway based on ultra-high activity chemical reactions. Summary of the Invention

[0007] To address the aforementioned technical problems in the existing technology, this invention provides a method and system for eliminating battery thermal runaway based on ultra-high activity chemical reactions.

[0008] The present invention adopts the following technical solution:

[0009] This invention provides a method for eliminating battery thermal runaway based on ultra-highly active chemical reactions, comprising:

[0010] Step 1: Based on the battery management system, which integrates multiple sensor signals of temperature, voltage, gas concentration, and air pressure, when the temperature change rate ΔT / Δt > 10℃ / s and the air pressure change rate ΔP / Δt > 1kPa / s, or the temperature change rate ΔT / Δt > 10℃ / s and the carbon monoxide concentration > 200ppm, the battery is determined to have entered the thermal runaway initiation stage.

[0011] Step 2: Calculate the actual amount of ultra-high activity chemical agent to be used based on the battery type and capacity, according to the stoichiometry and safety excess factor;

[0012] Step 3: Inject the amount of ultra-high activity chemical agent calculated in Step 2 into the battery, which is in the initial stage of thermal runaway, through the battery's pre-set fusible sealed micro-injection channel.

[0013] Step 4: The ultra-highly active chemical agent undergoes a violent chemical reaction with the electrolyte and / or active electrode materials inside the battery, instantly consuming the key reactants in the electrolyte and converting them into stable, non-flammable solid products and / or gaseous products. This causes the electrolyte to undergo irreversible deactivation, eliminating the chemical basis for the continued thermal runaway and terminating the battery's thermal runaway chain reaction.

[0014] Furthermore, step 2 includes:

[0015] The ultra-high activity chemical agent is a substance that can trigger the above-mentioned violent chemical reaction within milliseconds, and the chemical reaction includes at least one of oxidation, reduction, halogenation, hydrolysis, alkylation, and complexation.

[0016] Furthermore, the ultra-high activity chemical agent in step 2 includes:

[0017] The ultra-high activity chemical agent includes one or more of alkyl metal compounds, halogens and interhalogen compounds, strong Lewis acids, and active metal powders; wherein the alkyl metal compound is trimethylaluminum or n-butyllithium, the halogen and interhalogen compound is chlorine, chlorine trifluoride or bromine pentafluoride, the strong Lewis acid is antimony pentafluoride or boron trifluoride, and the active metal powder is nano-sized calcium powder or magnesium powder.

[0018] Furthermore, the actual amount of the ultra-high activity chemical agent used in step 2 includes:

[0019] Actual usage n3 = molar amount of key reactant in electrolyte n2 × reaction molar ratio r × safety factor k;

[0020] Among them, n2 is estimated based on battery capacity. The molar amount of key reactants in the electrolyte of a 1kWh ternary lithium-ion battery is 2.5mol, that of a 1kWh lithium iron phosphate battery is 2.2mol, that of a 1kWh lithium metal battery is 3.0mol, and that of a 1kWh sodium-ion battery is 2.0mol. The value of k ranges from 1.2 to 2.0. When the battery ambient temperature is >40℃ or the number of cycles is >80%, k is adjusted to 1.8.

[0021] Furthermore, the possible values ​​for the reaction molar ratio r include:

[0022] When the ultra-highly active chemical agent is trimethylaluminum, r = 1:1, which is the molar ratio of trimethylaluminum to the electrolyte solvent EC / DMC; when the ultra-highly active chemical agent is chlorine trifluoride, r = 3:1, which is the molar ratio of ClF3 to the electrolyte solvent EC / DMC.

[0023] Furthermore, the solid product and / or gaseous product in step 4 includes:

[0024] When the ultra-high activity chemical agent is trimethylaluminum, the solid products generated by the reaction of trimethylaluminum with the electrolyte EC / DMC are Al2O3, LiF, and carbon, and the gaseous product is CH4.

[0025] When the ultra-high activity chemical agent is chlorine trifluoride, the solid products generated by the reaction of chlorine trifluoride with the electrolyte are LiF and carbon slag, and the gaseous products are CF4, Cl2 and CO2.

[0026] Furthermore, the criteria for determining irreversible deactivation of the electrolyte in step 4 include:

[0027] The electrolyte ionic conductivity decreased from the initial 10.2 mS / cm to below 0.1 mS / cm, and the electrolyte solidification time was <100 ms, which was confirmed by shooting with a 1000fps high-speed camera.

[0028] This invention also provides a battery thermal runaway eradication system based on ultra-high activity chemical reactions, comprising:

[0029] The intelligent control unit communicates with the battery management system and is equipped with a thermal runaway initiation point judgment algorithm and a formulation dosage calculation module. It can determine the T1 point based on sensor signals, calculate the required formulation dosage, and output trigger commands.

[0030] The formulation storage unit includes at least one storage tank, which is made of Hastelloy C-276 or 316L stainless steel lined with polytetrafluoroethylene. The tank is kept in an inert atmosphere with a purity of ≥99.999%, and the oxygen content and water content in the atmosphere are <1ppm and <5ppm. The tank stores ultra-high activity chemical formulations, and the tank has a built-in pressure sensor that automatically opens the inert gas pressure relief valve when the pressure inside the tank is >1MPa.

[0031] The precision injection unit includes a corrosion-resistant pipeline connected to the formulation storage unit, an ultra-high-speed solenoid valve, and a retractable puncture-type guide nozzle. The retractable puncture-type guide nozzle includes a carbide needle tip, a brass nozzle body, a telescopic mechanism driven by a micro cylinder, and a flared guide sleeve. The precision injection unit can receive instructions from the intelligent control unit to drive the nozzle to align with the fusible seal micro injection channel of the battery, puncture the seal, and inject the formulation into the battery at a preset pressure.

[0032] The battery's internal channel, near the pressure relief valve on the battery cover, integrates a fusible seal-type miniature injection channel. The injection channel includes a stainless steel body, a fusible alloy sealing sheet, and an outer guide groove. The channel can be automatically opened by nozzle puncture or when the internal pressure is >1.5 atm.

[0033] Furthermore, the battery thermal runaway eradication system based on ultra-highly active chemical reactions also includes a safety protection unit, which includes:

[0034] The leakage monitoring module deploys dedicated sensors around the formulation storage unit and pipelines. Trimethylaluminum leakage is detected by infrared sensors, and ClF3 leakage is detected by ion-selective electrodes. An alarm is triggered when the leakage concentration is >0.1ppm.

[0035] Emergency neutralization module, equipped with anhydrous ethanol spray and calcium fluoride powder;

[0036] In addition to the pressure relief valve built into the storage tank, a pressure relief channel is added to the cabinet where the battery is located to prevent overpressure caused by gas generation during the reaction.

[0037] Furthermore, the precision injection unit has an injection pressure of 0.8 MPa, and after injection, the nozzle immediately retracts via a telescopic mechanism to avoid being damaged by the internal pressure of the battery.

[0038] Compared with the prior art, the superior effects of the present invention are as follows:

[0039] 1. The battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this invention transforms the electrolyte into stable and non-flammable solid products and / or low-risk gaseous products through reactions such as oxidation, reduction, halogenation, hydrolysis, and complexation. This completely destroys the chain cycle of electrolyte decomposition → exothermic reaction → accelerated reaction, with an expected re-ignition rate of zero, thus solving the core problem of existing technologies that only treat the symptoms and not the root cause.

[0040] 2. The battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this invention uses a pre-set fusible sealed micro-injection channel in the battery, which is directly connected to the electrolyte chamber. Combined with a retractable puncture-type guide nozzle, the preparation can be accurately injected into the electrode-electrolyte reaction zone inside the cell, solving the defect of existing technology that cannot reach the core reaction zone and ensuring that the reaction covers the root cause of thermal runaway.

[0041] 3. The battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this invention captures the chemical characteristics of the initial stage of thermal runaway, and can identify the T1 point before the battery surface temperature rises significantly. The warning time is 200-300ms earlier than the prior art, reserving a critical window for subsequent intervention.

[0042] 4. The battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this invention is based on the molar conservation calculation of reactants to ensure that the formulation exactly consumes the key components of the electrolyte; at the same time, the k value can be adjusted to 1.8 according to the ambient temperature > 40℃ or the number of cycles > 80%, so as to balance sufficient reaction and avoid excessive waste, thereby reducing the cost of use;

[0043] 5. The battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this invention addresses the root cause of thermal runaway by achieving a breakthrough in the principle of active chemical elimination. It realizes comprehensive advantages such as millisecond-level response, root cause termination, zero reignition rate, multi-system compatibility, and end-to-end safety. It not only solves the ultimate challenge in the current battery safety field but also provides underlying technical support for the safe implementation of next-generation high-energy-density batteries and new energy storage systems, demonstrating significant technological foresight and industrial value. Attached Figure Description

[0044] Figure 1 This is a block diagram illustrating the working principle of the battery thermal runaway eradication method based on ultra-high activity chemical reaction described in this embodiment of the invention.

[0045] Figure 2 This is a schematic diagram of the reaction between the ultra-highly active chemical agent and the electrolyte in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the experimental apparatus of Embodiment 1 of the present invention;

[0047] Figure 4 This is a schematic diagram of a ClF3-based system applied to an energy storage battery cabinet in an embodiment of the present invention.

[0048] Figure label:

[0049] 1. Lithium battery; 2. Positive electrode; 3. Negative electrode; 4. Separator; 5. First electrolyte; 6. Pressure relief valve; 7. Thermal runaway initiation point; 8. Stable non-flammable solid products; 9. Quartz glass sealed reaction chamber; 10. Argon inlet; 11. Pressure relief valve; 12. Pressure sensor; 13. Thermocouple probe; 14. Heating dish; 15. TMA solution; 16. PID temperature-controlled heating power supply; 17. Sample tray; 18. Second electrolyte; 19. In-situ conductivity probe; 20. Conductivity meter; 21. Argon cylinder; 22. Camera; 24. Energy storage battery cabinet; 25. Battery module; 26. Sensor; 27. BMS; 28. Reagent storage tank; 29. ​​Nitrogen pressurization device; 30. Injection pipeline; 31. Ultra-high speed solenoid valve; 32. Retractable puncture nozzle; 33. Intelligent control unit; 34. Injection channel. Detailed Implementation

[0050] To better understand the above-mentioned objectives, features and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0051] Example

[0052] like Figure 1As shown, the battery thermal runaway eradication method based on ultra-high activity chemical reactions includes:

[0053] Step 1: Based on the battery management system, which integrates signals from multiple sensors such as temperature, voltage, gas concentration, and gas pressure, the battery is determined to have entered the initial stage of thermal runaway when the temperature change rate ΔT / Δt > 10℃ / s and the gas pressure change rate ΔP / Δt > 1kPa / s, or the temperature change rate ΔT / Δt > 10℃ / s and the carbon monoxide concentration > 200ppm.

[0054] Step 2: Calculate the actual amount of ultra-high activity chemical agent to be used based on the battery type and capacity, according to the stoichiometry and safety excess factor;

[0055] Step 3: Inject the amount of ultra-high activity chemical agent calculated in Step 2 into the battery, which is in the initial stage of thermal runaway, through the battery's pre-set fusible sealed micro-injection channel.

[0056] Step 4: The ultra-highly active chemical agent undergoes a violent chemical reaction with the electrolyte and / or active electrode materials inside the battery, instantly consuming the key reactants in the electrolyte and converting them into stable, non-flammable solid products and / or gaseous products. This causes the electrolyte to undergo irreversible deactivation, eliminating the chemical basis for the continued thermal runaway and terminating the battery's thermal runaway chain reaction.

[0057] Furthermore, step 2 includes:

[0058] The ultra-high activity chemical agent is a substance that can trigger the above-mentioned violent chemical reaction within milliseconds, and the chemical reaction includes at least one of oxidation, reduction, halogenation, hydrolysis, alkylation, and complexation.

[0059] Specifically, such as Figure 2 As shown, the present invention introduces one or more ultra-highly active chemical agents into the interior of a battery that has experienced thermal runaway. These agents can undergo a violent and self-sustaining chemical reaction with the battery electrolyte (solvent and / or lithium salt) and / or active electrode materials, instantly consuming the reactants and converting them into stable, non-flammable solid or gaseous products, thereby completely destroying the chemical environment in which thermal runaway occurs.

[0060] The following reaction process uses the reaction of trimethylaluminum with ternary lithium-ion battery electrolyte as an example:

[0061] Initial state:

[0062] The lithium battery 1 is initially a sealed ternary lithium-ion battery (abbreviated as: lithium battery 1). The internal structure consists of alternating stacked positive electrode 2, negative electrode 3, and separator 4. The first electrolyte 5 fills the pores of the electrode and separator 4. The battery cover integrates a fusible sealed miniature injection channel 34 and a pressure relief valve 6. The external structure is connected to an intelligent control unit 33 and associated with multiple pressure sensors 12 of the BMS27 (battery management system).

[0063] The positive electrode 2 uses a ternary active material, such as LiNi0.8Co0.1Mn0.1O2, with a thin SEI film coated on the surface. Under normal operating conditions, charging and discharging are achieved through Li+ insertion and extraction.

[0064] The negative electrode 3 is made of graphite material, with a stable SEI film formed on its surface. Lithium carbonate, alkyl lithium carbonate, etc., are inserted / extracted here.

[0065] Membrane 4 is a polypropylene / polyethylene composite microporous membrane with a pore size of 20-50 nm, which only allows Li+ to pass through and separates the positive electrode 2 and the negative electrode 3 to prevent short circuits.

[0066] Electrolyte 5 uses EC ethylene carbonate / DMC dimethyl carbonate as solvent at a volume ratio of 1:1 to dissolve LiPF6 lithium salt, with an ionic conductivity of 10.2 mS / cm, providing a medium for Li+ transport.

[0067] The pressure relief valve 6 is initially closed and is set to open at a pressure of 1.5 to 2 atm. It is used to discharge excess gaseous products in the event of thermal runaway to prevent the lithium battery 1 from exploding.

[0068] Thermal runaway initiation point 7, when not triggered, lithium battery 1 is normal, and point T1 is in a latent state;

[0069] Stable, non-flammable solid product 8 is initially absent and is only generated after the formulation reacts with the first electrolyte 5.

[0070] Phase 1: Thermal runaway begins, triggered at T1 point, with abnormal activation in various parts:

[0071] Thermal runaway initiation point 7, the triggering core is the surface of positive electrode 2. Due to overcharging, internal short circuit, or SEI film aging in the later stages of cycling of lithium battery 1, the local temperature rises sharply, and the SEI film on the surface of negative electrode 3 ruptures.

[0072] Li₂CO₃→Li₂O+CO₂↑

[0073] The ruptured SEI film loses its protective function, and the metallic lithium in the negative electrode graphite comes into direct contact with the solvent of the first electrolyte 5, triggering a violent exothermic reaction:

[0074] Li + EC → Li₂CO₃ + C₂H₄↑ + Heat

[0075] At the same time, the gas produced by the reaction causes a sudden increase in the internal gas pressure of the lithium battery 1, or the first electrolyte 5 decomposes to produce CO, which meets the T1 point judgment condition, and the intelligent control unit 33 triggers the preparation injection command.

[0076] The negative electrode 3 continuously undergoes a lithium-first electrolyte 5 reaction on its surface, causing the local temperature to rise above 85°C, which triggers the softening of the fusible alloy sheet of the fusible sealed micro injection channel 34 on the cover plate of the lithium battery 1.

[0077] The heat released from cathode 2 and anode 3 is conducted to cathode 2, causing the ternary material at cathode 2 to begin delithiation and release lattice oxygen.

[0078] LiNi0.8Co0.1Mn0.1O2→Li 1-x Ni0.8Co0.1Mn0.1O2+xLi + +xe - +O2↑

[0079] The released O2 further oxidizes the electrolyte solvent 5, exacerbating thermal runaway;

[0080] Under the dual effects of the exothermic reaction at the negative electrode 3 and the oxygen release at the positive electrode 2, the solvent EC / DMC in the first electrolyte 5 decomposes rapidly, and LiPF6 hydrolyzes to produce HF. The ionic conductivity of the first electrolyte 5 begins to decrease, but it still maintains high activity and continues to provide a medium for the chain reaction.

[0081] Due to the local high temperature, the PP layer of the diaphragm 4 begins to close its pores in an attempt to block Li+ transport. However, even after the pores are closed, liquid first electrolyte 5 remains in the pores of the diaphragm 4, which cannot prevent the decomposition reaction of the first electrolyte 5 that has already been initiated.

[0082] Pressure relief valve 6 is closed at this time because the internal gas pressure of lithium battery 1 has not yet reached the opening pressure of the pressure relief valve, thus creating a sealed environment for the subsequent targeted injection of preparations into lithium battery 1.

[0083] Phase 2: Injection of ultra-highly active chemical agents and core reaction:

[0084] The intelligent control unit 33 commands the precision injection unit to start, and the retractable piercing nozzle 32 is aligned with the injection channel 34 guide groove of the lithium battery 1 cover plate. The micro cylinder drives the nozzle to move forward, piercing the softened fusible alloy sheet, and injecting the calculated amount of liquid TMA solution 15 into the battery with a pressure of 0.8MPa.

[0085] Immediately after TMA solution 15 is injected, it undergoes a rapid and intense multi-step reaction with trace amounts of water, EC / DMC solvent, and LiPF6 lithium salt in the first electrolyte 5. The reaction process is as follows:

[0086] ① First step (hydrolysis reaction): TMA solution 15 preferentially reacts with trace amounts of water in the first electrolyte 5, releasing heat but posing no risk of combustion or explosion.

[0087] Al(CH3)3 + 3H2O → Al(OH)3↓ (white solid) + 3CH4↑ (gas phase product)

[0088] ② Second step (alkylation and solvent decomposition reaction): Excess TMA solution 15 undergoes an alkylation reaction with EC / DMC solvent, completely consuming solvent molecules:

[0089] Al(CH3)3 + EC → Al(CH3) x (OCO2C2H4) γ ↓(intermediate state) + C2H6↑

[0090] Al(CH3)3 + DMC → Al(CH3) a (OCO2CH3) β ↓(intermediate state) + CH4↑

[0091] ③ Third step (lithium salt decomposition reaction): The Al(OH)3 generated in the reaction reacts with LiPF6 in the electrolyte, destroying the lithium salt structure:

[0092] Al(OH)3 + LiPF6 → LiF↓ (white solid) + AlF3 + 3HF↑ (consumed by subsequent reactions in TMA solution 15)

[0093] The above reaction was completed within 80ms. The first electrolyte 5 rapidly changed from a transparent liquid to a viscous paste, and the ionic conductivity dropped sharply to 0.045mS / cm.

[0094] Some of the TMA solution 15 that did not react with the first electrolyte 5 diffused to the surfaces of the positive electrode 2 and the negative electrode 3, where it reacted with the O2 released from the positive electrode 2 and the lithium dendrites remaining in the negative electrode 3.

[0095] Reaction with positive electrode 2O2: 4Al(CH3)3 + 15O2 → 2Al2O3↓ (solid) + 12CO2↑ + 18H2O (the generated H2O participates again in the hydrolysis of TMA solution 15);

[0096] Reaction with lithium dendrites at the negative electrode: Al(CH3)3 + 3Li → AlLi3 + 3CH4↑ (consuming active lithium and avoiding short circuits caused by lithium dendrites);

[0097] The two types of reactions further eliminate thermally runaway reactants (O2, lithium dendrites) and enhance the termination effect.

[0098] The solid particles such as Al2O3 and LiF generated by the reaction of the first electrolyte 5 flow with the electrolyte and quickly fill the micropores of the membrane 4 to form a solid blocking layer. Even if the membrane 4 is not completely closed, it can completely block the Li+ transport path and terminate the electrochemical reaction from the ion conduction level.

[0099] The gaseous products such as CH4 and CO2 generated by the reaction of TMA solution 15 cause the internal gas pressure of lithium battery 1 to rise to 1.5-2 atm, reaching the opening pressure of pressure relief valve 6. Pressure relief valve 6 opens automatically, safely discharging the gaseous products outside lithium battery 1.

[0100] Phase 3: Thermal runaway completely terminated

[0101] After the reaction is complete, the solid products generated inside lithium battery 1 are mainly distributed in the following locations:

[0102] In the first electrolyte zone 5, Al2O3 and LiF are uniformly dispersed to form a non-flammable solid paste, completely replacing the original active electrolyte.

[0103] On the surfaces of positive electrode 2 and negative electrode 3: Al2O3 and carbon slag adhere to the surfaces of positive electrode 2 and negative electrode 3, forming an inert protective layer to prevent positive electrode 2 and negative electrode 3 from reacting further with the residual electrolyte;

[0104] The membrane has four pores: Al2O3 and LiF particles block the micropores, forming an ion-insulating layer;

[0105] All of the above solid products are stable and non-flammable substances, completely eliminating the chemical basis for the continuous thermal runaway reaction.

[0106] At thermal runaway initiation point 8, the SEI film rupture area on the surface of negative electrode 3 was covered by solid products, and the local temperature dropped from the peak to the ambient temperature. BMS27 monitored that ΔT / Δt < 0.1℃ / s and the CO concentration no longer increased, indicating that the chain reaction at thermal runaway initiation point 8 was completely terminated.

[0107] There is no continuous heat release or new gas generation inside lithium battery 1. As the gas pressure drops, the pressure relief valve 6 gradually closes, and lithium battery 1 enters a safe inert state. Even if the ambient temperature rises or it is subjected to vibration, it will not reignite, thus achieving the ultimate goal of eliminating thermal runaway.

[0108] Furthermore, the ultra-high activity chemical agent in step 2 includes:

[0109] The ultra-high activity chemical agent includes one or more of alkyl metal compounds, halogens and interhalogen compounds, strong Lewis acids, and active metal powders; wherein the alkyl metal compound is trimethylaluminum or n-butyllithium, the halogen and interhalogen compound is chlorine, chlorine trifluoride or bromine pentafluoride, the strong Lewis acid is antimony pentafluoride or boron trifluoride, and the active metal powder is nano-sized calcium powder or magnesium powder.

[0110] Specifically, alkyl metal compounds, such as trimethylaluminum (TMA) and n-butyllithium, function to undergo vigorous hydrolysis and alkylation reactions with trace amounts of water, solvent molecules, esters, and ethers in the electrolyte, consuming the solvent and generating metal oxides / hydroxides and alkane gases.

[0111] Halogens and interhalogen compounds, such as chlorine (Cl2), chlorine trifluoride (ClF3), and bromine pentafluoride (BrF5), function as strong oxidizing and halogenating agents to thoroughly oxidize and halogenate organic solvents, causing them to carbonize or generate non-flammable halogenated hydrocarbons.

[0112] Strong Lewis acids, such as antimony pentafluoride (SbF5) and boron trifluoride (BF3), function to strongly complex anions in the electrolyte, such as PF6. - This disrupts the lithium salt structure and simultaneously catalyzes the decomposition and polymerization of solvent molecules.

[0113] Active metal powders, such as nano-sized calcium powder and magnesium powder, function to react directly with electrolyte 5 and consume the evolved oxygen to generate stable metal oxides.

[0114] Trimethylaluminum TMA solution 15, protected in liquid and inert atmosphere;

[0115] n-Butyllithium exists in solution form in inert solvents, such as n-hexane and cyclohexane, and is sealed in a container filled with an inert atmosphere, such as high-purity nitrogen or argon.

[0116] Cl2, compressed liquefied petroleum gas; chlorine trifluoride ClF3, compressed liquefied petroleum gas; bromine pentafluoride BrF5, compressed liquefied petroleum gas; antimony pentafluoride SbF5, viscous liquid; boron trifluoride BF3, compressed liquefied petroleum gas; nano-metal powders (such as Ca, Mg) and inert gases (such as N2, Ar) form aerosols.

[0117] For high-risk formulations such as TMA solution 15 which spontaneously combusts upon contact with water and ClF3 which is highly corrosive / combustion-supporting, safety measures are designed according to different scenarios:

[0118] Storage cell security:

[0119] Tank material: Hastelloy C-276, resistant to ClF3 corrosion or 316L stainless steel lined with PTFE, resistant to TMA solution 15;

[0120] Atmosphere control: Fill with 99.999% argon gas, inert atmosphere, oxygen content <1ppm, water content <5ppm, to prevent spontaneous combustion of TMA solution after hydrolysis at 15°C;

[0121] Pressure monitoring: Built-in pressure sensor automatically opens the inert gas relief valve when the overpressure is >1MPa, preventing direct discharge;

[0122] Safe to use:

[0123] Remote triggering: The injection command is issued remotely from the central control room, requiring no on-site operation.

[0124] Leakage detection involves deploying dedicated sensors around the storage tank and pipelines. Sensor 26 (temperature, pressure, voltage) is used for TMA solution 15, and ion-selective electrodes are used for ClF3. An alarm is triggered when the leakage concentration is >0.1ppm.

[0125] For emergency neutralization, TMA solution 15 leakage was neutralized by spraying with anhydrous ethanol to generate harmless Al(OEt)3, and ClF3 leakage was adsorbed by calcium fluoride powder to generate stable CaF2.

[0126] Personnel protection: Maintenance personnel are equipped with positive pressure respirators, fluororubber protective clothing and chemical-resistant gloves, and are strictly prohibited from bringing water-containing items into the storage area.

[0127] Furthermore, the actual amount of the ultra-high activity chemical agent used in step 2 includes:

[0128] Actual usage n3 = molar amount of key reactant in electrolyte n2 × reaction molar ratio r × safety factor k;

[0129] Among them, n2 is estimated based on battery capacity. The molar amount of key reactants in the electrolyte of a 1kWh ternary lithium-ion battery is 2.5mol, that of a 1kWh lithium iron phosphate battery is 2.2mol, that of a 1kWh lithium metal battery is 3.0mol, and that of a 1kWh sodium-ion battery is 2.0mol. The value of k ranges from 1.2 to 2.0. When the battery ambient temperature is >40℃ or the number of cycles is >80%, k is adjusted to 1.8.

[0130] Furthermore, the possible values ​​for the reaction molar ratio r include:

[0131] When the ultra-highly active chemical agent is trimethylaluminum, r = 1:1, which is the molar ratio of trimethylaluminum to the electrolyte solvent EC / DMC; when the ultra-highly active chemical agent is chlorine trifluoride, r = 3:1, which is the molar ratio of ClF3 to the electrolyte solvent EC / DMC.

[0132] Furthermore, the solid product and / or gaseous product in step 4 includes:

[0133] When the ultra-high activity chemical agent is trimethylaluminum, the solid products generated by the reaction of trimethylaluminum with the electrolyte EC / DMC are Al2O3, LiF, and carbon, and the gaseous product is CH4.

[0134] When the ultra-high activity chemical agent is chlorine trifluoride, the solid products generated by the reaction of chlorine trifluoride with the electrolyte are LiF and carbon slag, and the gaseous products are CF4, Cl2 and CO2.

[0135] Furthermore, the criteria for determining irreversible deactivation of the electrolyte in step 4 include:

[0136] The electrolyte ionic conductivity decreased from the initial 10.2 mS / cm to below 0.1 mS / cm, and the electrolyte solidification time was <100 ms, which was confirmed by shooting with a 1000fps high-speed camera.

[0137] This invention also provides a battery thermal runaway eradication system based on ultra-high activity chemical reactions, comprising:

[0138] The intelligent control unit communicates with the battery management system and is equipped with a thermal runaway initiation point judgment algorithm and a formulation dosage calculation module. It can determine the T1 point based on sensor signals, calculate the required formulation dosage, and output trigger commands.

[0139] The formulation storage unit includes at least one storage tank, which is made of Hastelloy C-276 or 316L stainless steel lined with polytetrafluoroethylene. The tank is kept in an inert atmosphere with a purity of ≥99.999%, and the oxygen content and water content in the atmosphere are <1ppm and <5ppm. The tank stores ultra-high activity chemical formulations, and the tank has a built-in pressure sensor that automatically opens the inert gas pressure relief valve when the pressure inside the tank is >1MPa.

[0140] The precision injection unit includes a corrosion-resistant pipeline connected to the formulation storage unit, an ultra-high-speed solenoid valve, and a retractable puncture-type guide nozzle. The retractable puncture-type guide nozzle includes a carbide needle tip, a brass nozzle body, a telescopic mechanism driven by a micro cylinder, and a flared guide sleeve. The precision injection unit can receive instructions from the intelligent control unit to drive the nozzle to align with the fusible seal micro injection channel 34 of the battery, puncture the seal, and inject the formulation into the battery at a preset pressure.

[0141] The battery has an internal channel. Near the pressure relief valve, the battery cover plate integrates a fusible seal-type miniature injection channel 34. The injection channel 34 includes a stainless steel body, a fusible alloy sealing sheet, and an outer guide groove. The channel can be automatically opened by nozzle puncture or when the internal pressure is >1.5 atm.

[0142] Specifically, the formulation storage unit is composed of a tank made of special corrosion-resistant alloy or lined with anti-corrosion material, and the interior is maintained in an inert atmosphere for the safe storage of the ultra-high activity chemical formulation.

[0143] The precision injection unit, including an ultra-high-speed solenoid valve, corrosion-resistant piping and nozzles, is used to inject a fixed amount of preparation into the battery or a predetermined location after receiving an instruction.

[0144] The basic parameters of different battery systems are shown in Table 1. The basis for determining n2 is as follows:

[0145] Table 1

[0146]

[0147] The dosage correspondence is shown in Table 2. Taking TMA as an example, r = 1:1, k = 1.5:

[0148] Table 2

[0149]

[0150] The total electrolyte volume is estimated by considering the battery's rated capacity, energy density, and electrolyte percentage. For example, a 100kWh ternary lithium battery weighs approximately 400kg, so the electrolyte mass = 400kg × 15% = 60kg, the volume ≈ 60L, and the electrolyte density ≈ 1g / cm³. 3 );

[0151] Safety factor adjustment: When the battery is in a high temperature environment >40℃ or the number of cycles >80%, k is increased to 1.8. Because the electrolyte may partially decompose, the amount of formulation needs to be increased.

[0152] On-site calibration: For the first application, a verification experiment was conducted using a small-capacity 10Ah battery, and the amount of micro-adjustment was adjusted based on the actual curing time (target <100ms).

[0153] The intelligent control unit, based on the battery management system BMS27, determines the thermal runaway initiation point 7T1 by integrating multiple sensor signals such as voltage, temperature, air pressure, and gas, and issues a trigger command.

[0154] The multi-sensor 26-fusion judgment logic has quantifiable thresholds as shown in Table 3:

[0155] Table 3

[0156]

[0157]

[0158] The triggering condition is that if both temperature and air pressure are abnormal, or temperature and gas are abnormal, then it is determined to be point T1 and a trigger command is issued.

[0159] Safety protection unit (optional), including subsystems such as leak detection, emergency neutralization, and pressure relief, is used to improve the safety of the entire system.

[0160] Furthermore, the battery thermal runaway eradication system based on ultra-highly active chemical reactions also includes a safety protection unit, which includes:

[0161] The leakage monitoring module deploys dedicated sensors around the formulation storage unit and pipelines. Trimethylaluminum leakage is detected by infrared sensors, and ClF3 leakage is detected by ion-selective electrodes. An alarm is triggered when the leakage concentration is >0.1ppm.

[0162] Emergency neutralization module, equipped with anhydrous ethanol spray and calcium fluoride powder;

[0163] In addition to the pressure relief valve built into the storage tank, a pressure relief channel is added to the cabinet where the battery is located to prevent overpressure caused by gas generation during the reaction.

[0164] Furthermore, the precision injection unit has an injection pressure of 0.8 MPa, and after injection, the nozzle immediately retracts via a telescopic mechanism to avoid being damaged by the internal pressure of the battery.

[0165] The working principle and method of this invention:

[0166] Early warning: BMS27 has identified early thermal runaway T1 characteristics through a multi-parameter fusion algorithm;

[0167] The decision-making and control unit locates the fault point and calculates the required dosage.

[0168] Triggering the injection unit activates the system, injecting the formulation through the battery pressure relief valve or a dedicated channel;

[0169] The reaction occurs when the preparation enters the battery and comes into contact with components such as the electrolyte, resulting in a violent chemical reaction, as shown in the examples below, accompanied by a large amount of exothermic / endothermic and gas production.

[0170] Example reaction, using alkylaluminum as an example:

[0171] Al(CH3)3+3H2O→Al(OH)3↓+3CH4↑

[0172] Al(CH3)3+(EC / DMC) → ...complex decomposition and alkylation reactions;

[0173] Termination occurs when the electrolyte is consumed or converted into solid residue, the ion transport pathway is completely destroyed, and the thermal runaway reaction is eradicated.

[0174] The battery has a dedicated injection channel 34 designed for it.

[0175] A fusible, sealed micro-injection channel needs to be integrated during the battery design phase, with the specific structure as follows:

[0176] The channel is located on the battery cover near the pressure relief valve, at a distance of ≤5mm, and is directly connected to the electrolyte chamber inside the battery; the channel structure is as follows:

[0177] The main body is made of stainless steel, with an inner diameter of 1.5mm and a length of 5mm. The inner wall is treated with anti-corrosion coating and sprayed with polytetrafluoroethylene.

[0178] The sealing element at the channel inlet uses a fusible alloy sheet with a melting point of 85℃ and a composition of Bi50 / Pb25 / Sn25, with a thickness of 0.2mm; the auxiliary structure has a guide groove with a diameter of 3mm on the outside of the channel inlet for nozzle alignment and positioning.

[0179] Triggering mechanism:

[0180] Active puncture: After receiving the command, the injection unit drives the nozzle needle tip to puncture the fusible alloy sheet;

[0181] Passive activation: If the pressure rises above 1.5 atm in the initial stage of thermal runaway, the fusible alloy sheet will automatically rupture, opening the channel.

[0182] Nozzle design scheme:

[0183] It adopts a retractable puncture-type guide nozzle, as described in detail below:

[0184] Core structure:

[0185] The needle tip, made of WC-Co carbide, has a tip diameter of 0.5mm and is used for piercing seals.

[0186] The nozzle body is made of brass with an inner diameter of 1mm. The outlet has a conical structure with a diffusion angle of 15° to improve the spray coverage.

[0187] The telescopic mechanism, driven by a miniature cylinder, has a stroke of 10mm and a telescopic speed of 0.1m / s, ensuring rapid docking.

[0188] The guide sleeve has a flared shape at the front end of the nozzle, with an inner diameter of 3mm, which matches the groove of the battery channel and has a positioning accuracy of ±0.2mm.

[0189] Workflow:

[0190] Alignment: The nozzle is moved to the top of the battery channel guide groove via a mechanical positioning mechanism;

[0191] The cylinder drives the nozzle forward, and the needle tip punctures the fusible alloy sheet.

[0192] The agent is sprayed from the nozzle at a pressure of 0.8 MPa and injected into the battery through the channel;

[0193] After spraying, the nozzle should be retracted immediately to avoid damage from the internal pressure of the battery.

[0194] Example 1, such as Figure 3 As shown, a laboratory demonstration based on trimethylaluminum (TMA) vapor injection:

[0195] Objective: To verify the ability of the ultra-high activity formulation to cause transient failure of the second electrolyte 18;

[0196] Set up in a quartz glass sealed reaction chamber 9, place a shallow dish of commercial lithium-ion battery second electrolyte 18, 1M LiPF6 in EC / DMC, and place a small amount of trimethylaluminum TMA solution 15 in a heating dish.

[0197] In the process, the TMA solution 15 is remotely heated to release its vapor and bring it into contact with the vapor of the second electrolyte 18;

[0198] As a result, a large amount of white smoke (Al(OH)3 and lithium salt decomposition products) and bubbles (CH4, etc.) were observed to be generated instantaneously, and the second electrolyte 18 quickly solidified and failed. This experiment directly proves that violent chemical reactions can cause electrolytes to deactivate instantaneously.

[0199] The parameters of the experimental setup are shown in Table 4:

[0200] Table 4

[0201] Parameter categories Specific values Control method Reaction chamber specifications 5L capacity, made of quartz glass Sealed type, with pressure relief valve (set pressure 2 atm) initial temperature 25℃±0.5℃ Thermostatic water bath jacket temperature control Initial pressure 1 atm (at normal pressure) Equilibrium after purging with inert gas (argon) Heating dish parameters 50W power, stainless steel material Remote PID temperature control, heating rate 10℃ / s

[0202] The dosage and specifications of the reagents are shown in Table 5:

[0203] Table 5

[0204]

[0205] The quantitative characterization of the experimental results is shown in Table 6:

[0206] Table 6

[0207]

[0208] The quartz glass sealed reaction chamber 9 provides a transparent, sealed, and corrosion-resistant reaction vessel to meet the needs of experimental observation and inert environment;

[0209] Argon inlet 10 serves as an inert gas inlet channel, creating a water-free and oxygen-free protective atmosphere for the reaction chamber;

[0210] Pressure relief valve 11 controls the pressure inside the reaction chamber to prevent overpressure explosion caused by gas production during the reaction and to ensure experimental safety.

[0211] Pressure sensor 12 monitors pressure changes in the reaction chamber in real time, providing a basis for pressure relief valve linkage and experimental data recording;

[0212] Thermocouple probe 13 accurately measures the real-time temperature inside the reaction chamber and the electrolyte to verify whether the exothermic reaction is controllable.

[0213] The heating dish 14 holds the TMA solution 15. By heating, the TMA solution 15 is converted from liquid to vapor, realizing the experimental design of vapor injection.

[0214] TMA solution 15 is a carrier for experimental ultra-high activity chemical reagents, providing the vapor of TMA solution 15 required for the reaction;

[0215] The PID temperature control heating power supply 16 precisely controls the heating rate and target temperature of the heating dish 14, ensuring stable and controllable release of vapor from the TMA solution 15;

[0216] The sample tray 17 carries the electrolyte 18 and provides a contact reaction interface between the vapor of the TMA solution 15 and the electrolyte.

[0217] The second electrolyte 18 is the target reaction medium in the experiment, simulating the electrolyte components in an actual battery, and verifying the deactivation effect of TMA solution 15 on it.

[0218] The in-situ conductivity probe 19 monitors the changes in ionic conductivity of the second electrolyte 18 in real time and in situ, and quantifies the degree of deactivation of the second electrolyte 18.

[0219] The conductivity meter 20 receives the signal from the in-situ conductivity probe 19, converts the conductivity data into readable values, and records them.

[0220] Argon cylinder 21 provides the high-purity inert gas required for the experiment, and provides an anhydrous and oxygen-free environment for the storage and reaction of TMA solution 15;

[0221] Camera 22 visually records the entire experimental process, quantifies the electrolyte solidification time, and intuitively verifies the instantaneous nature of the reaction.

[0222] Example 2, as Figure 4 As shown, the conceptual system design based on ClF3 is as follows:

[0223] The purpose is to describe a complete system concept;

[0224] The system uses Hastelloy C-276 alloy storage tanks to store liquid ClF3, and the piping and valves are all specially treated for corrosion protection. The storage tanks are connected to the fire-fighting piping of a large energy storage battery cabinet;

[0225] During the process, when the BMS and gas sensors detect signs of thermal runaway of the battery inside the cabinet, the control unit commands the valve to open and inject a fixed amount of ClF3 vapor into the cabinet.

[0226] The expected effect is that ClF3 reacts violently with the leaked electrolyte vapor and combustible gas to generate CF4, Cl2, CO2, as well as solid lithium fluoride and carbon slag, instantly eliminating combustibles and terminating the reaction.

[0227] The energy storage battery cabinet 24 serves as the physical carrier and safety boundary of the entire system, integrating battery modules, agent injection system and safety protection functions to meet the large-scale needs of energy storage scenarios.

[0228] Battery module 25, the energy storage unit of the energy storage system, is also a potential point of thermal runaway and needs to provide an adaptation structure for ClF3 injection;

[0229] Sensor 26 enables dual functions of thermal runaway early warning and formulation leakage monitoring, providing decision-making basis for intelligent control unit 33, and is key to early detection and early intervention of the system;

[0230] The BMS27 battery management system connects the battery status and the intelligent control unit, providing basic cell data and assisting in thermal runaway detection.

[0231] The intelligent control unit 33, the brain of the system, is responsible for thermal runaway determination, dosage calculation, and command issuance. It is the core central hub for achieving active annihilation.

[0232] Formulation storage tank 28 is used to safely store ClF3, ensuring its stability and corrosion resistance.

[0233] The nitrogen pressurization device 29 provides stable power for the delivery of ClF3, ensuring that it is injected into the battery at a preset pressure;

[0234] The injection pipeline 30 connects the preparation storage tank 28 and the nozzle 32 to achieve leak-free delivery of ClF3 and is compatible with the multi-module layout of the energy storage cabinet.

[0235] The ultra-high-speed solenoid valve 31 controls the start and stop of ClF3 injection and the dosage accuracy, and is a key actuator for achieving quantitative injection.

[0236] The retractable puncture nozzle 32 breaks through the battery shell barrier and precisely injects ClF3 into the runaway battery cell, which is the key to intervention in the core reaction area.

[0237] Injection channel 34 provides a directional channel for ClF3 injection, ensuring that the formulation reaches the electrolyte reaction zone inside the cell directly. Sensor 26 and BMS 27 capture the T1 point signal, and intelligent control unit 33 quickly determines and calculates the amount of ClF3 used. Nitrogen pressurization device 29 pushes ClF3 in storage tank 28 through injection pipeline 30 and ultra-high speed solenoid valve 31 to telescopic puncture nozzle 32. Telescopic puncture nozzle 32 punctures injection channel 34 to inject ClF3 into the runaway cell, reacting with second electrolyte 18 to generate stable solid products such as LiF and carbon slag, completely eliminating the chemical basis of thermal runaway.

[0238] This invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims.

Claims

1. A method for eliminating battery thermal runaway based on ultra-highly active chemical reactions, characterized in that, include: Step 1: Based on the battery management system, which integrates multiple sensor signals of temperature, voltage, gas concentration, and air pressure, when the temperature change rate ΔT / Δt > 10℃ / s and the air pressure change rate ΔP / Δt > 1kPa / s, or the temperature change rate ΔT / Δt > 10℃ / s and the carbon monoxide concentration > 200ppm, the battery is determined to have entered the thermal runaway initiation stage. Step 2: Calculate the actual amount of ultra-high activity chemical agent to be used based on the battery type and capacity, according to the stoichiometry and safety excess factor; Step 3: Inject the amount of ultra-high activity chemical agent calculated in Step 2 into the battery, which is in the initial stage of thermal runaway, through the battery's pre-set fusible sealed micro-injection channel. Step 4: The ultra-highly active chemical agent undergoes a violent chemical reaction with the electrolyte and / or active electrode materials inside the battery, instantly consuming the key reactants in the electrolyte and converting them into stable, non-flammable solid products and / or gaseous products. This causes the electrolyte to undergo irreversible deactivation, eliminating the chemical basis for the continued thermal runaway and terminating the battery's thermal runaway chain reaction.

2. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 1, characterized in that, Step 2 includes: The ultra-high activity chemical agent is a substance that can trigger the above-mentioned violent chemical reaction within milliseconds, and the chemical reaction includes at least one of oxidation, reduction, halogenation, hydrolysis, alkylation, and complexation.

3. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 2, characterized in that, The ultra-high activity chemical agent in step 2 includes: The ultra-high activity chemical agent includes one or more of alkyl metal compounds, halogens and interhalogen compounds, strong Lewis acids, and active metal powders; wherein the alkyl metal compound is trimethylaluminum or n-butyllithium, the halogen and interhalogen compound is chlorine, chlorine trifluoride or bromine pentafluoride, the strong Lewis acid is antimony pentafluoride or boron trifluoride, and the active metal powder is nano-sized calcium powder or magnesium powder.

4. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 1, characterized in that, The actual amount of the ultra-high activity chemical agent used in step 2 includes: Actual usage n3 = molar amount of key reactant in electrolyte n2 × reaction molar ratio r × safety factor k; Among them, n2 is estimated based on battery capacity. The molar amount of key reactants in the electrolyte of a 1kWh ternary lithium-ion battery is 2.5mol, that of a 1kWh lithium iron phosphate battery is 2.2mol, that of a 1kWh lithium metal battery is 3.0mol, and that of a 1kWh sodium-ion battery is 2.0mol. The value of k ranges from 1.2 to 2.

0. When the battery ambient temperature is >40℃ or the number of cycles is >80%, k is adjusted to 1.

8.

5. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 4, characterized in that, The possible values ​​for the reaction molar ratio r include: When the ultra-highly active chemical agent is trimethylaluminum, r = 1:1, which is the molar ratio of trimethylaluminum to the electrolyte solvent EC / DMC; when the ultra-highly active chemical agent is chlorine trifluoride, r = 3:1, which is the molar ratio of ClF3 to the electrolyte solvent EC / DMC.

6. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 1, characterized in that, The solid products and / or gaseous products in step 4 include: When the ultra-high activity chemical agent is trimethylaluminum, the solid products generated by the reaction of trimethylaluminum with the electrolyte EC / DMC are Al2O3, LiF, and carbon, and the gaseous product is CH4. When the ultra-high activity chemical agent is chlorine trifluoride, the solid products generated by the reaction of chlorine trifluoride with the electrolyte are LiF and carbon slag, and the gaseous products are CF4, Cl2 and CO2.

7. The battery thermal runaway eradication method based on ultra-high activity chemical reaction according to claim 1, characterized in that, The criteria for determining irreversible deactivation of the electrolyte in step 4 include: The electrolyte ionic conductivity decreased from the initial 10.2 mS / cm to below 0.1 mS / cm, and the electrolyte solidification time was <100 ms, which was confirmed by shooting with a 1000fps high-speed camera.

8. A battery thermal runaway eradication system based on ultra-highly active chemical reactions, applied to the method described in any one of claims 1 to 7, characterized in that, include: The intelligent control unit communicates with the battery management system and is equipped with a thermal runaway initiation point judgment algorithm and a formulation dosage calculation module. It can determine the T1 point based on sensor signals, calculate the required formulation dosage, and output trigger commands. The formulation storage unit includes at least one storage tank, which is made of Hastelloy C-276 or 316L stainless steel lined with polytetrafluoroethylene. The tank is kept in an inert atmosphere with a purity of ≥99.999%, and the oxygen content and water content in the atmosphere are <1ppm and <5ppm. The tank stores ultra-high activity chemical formulations, and the tank has a built-in pressure sensor that automatically opens the inert gas pressure relief valve when the pressure inside the tank is >1MPa. The precision injection unit includes a corrosion-resistant pipeline connected to the formulation storage unit, an ultra-high-speed solenoid valve, and a retractable puncture-type guide nozzle. The retractable puncture-type guide nozzle includes a carbide needle tip, a brass nozzle body, a telescopic mechanism driven by a micro cylinder, and a flared guide sleeve. The precision injection unit can receive instructions from the intelligent control unit to drive the nozzle to align with the fusible seal micro injection channel of the battery, puncture the seal, and inject the formulation into the battery at a preset pressure. The battery's internal channel, near the pressure relief valve on the battery cover, integrates a fusible seal-type miniature injection channel. The injection channel includes a stainless steel body, a fusible alloy sealing sheet, and an outer guide groove. The channel can be automatically opened by nozzle puncture or when the internal pressure is >1.5 atm.

9. The battery thermal runaway eradication system based on ultra-high activity chemical reaction according to claim 8, characterized in that, It also includes a security protection unit, which includes: The leakage monitoring module deploys dedicated sensors around the formulation storage unit and pipelines. Trimethylaluminum leakage is detected by infrared sensors, and ClF3 leakage is detected by ion-selective electrodes. An alarm is triggered when the leakage concentration is >0.1ppm. Emergency neutralization module, equipped with anhydrous ethanol spray and calcium fluoride powder; In addition to the pressure relief valve built into the storage tank, a pressure relief channel is added to the cabinet where the battery is located to prevent overpressure caused by gas generation during the reaction.

10. The battery thermal runaway eradication system based on ultra-high activity chemical reaction according to claim 8, characterized in that, The precision injection unit has an injection pressure of 0.8 MPa, and after injection, the nozzle immediately retracts via a telescopic mechanism to avoid being damaged by the internal pressure of the battery.

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