Thermal protection for lithium-ion batteries

Abstract

This invention provides a method for stopping thermal runaway in lithium-ion batteries and a fire prevention system. [Solution] The method includes the steps of providing a housing 101, providing a lithium-ion battery (LIB) type device 103 powered by a lithium-ion battery (LIB) 102 located within the housing, and providing a thermal runaway arrestor supply source 104. The supply source includes a container 105 and a two-way control valve 106, the container containing the thermal runaway arrestor, the two-way control valve being attached to the opening of the container, and the thermal runaway arrestor containing HFC-227ea. The method also includes the step of providing a thermosensing tube 107 containing an inert gas or thermal runaway arrestor at a predetermined pressure and temperature suitable for the normal operating conditions of the device. The thermosensing tube has two ends, one end communicating with the two-way control valve and the other end sealed via a tube end seal 108, is located within the housing, and is positioned close to the lithium-ion battery and includes a temperature sensor for detecting a threshold temperature.

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims priority to U.S. Provisional Patent Application No. 63 / 107,052, filed Oct. 29, 2020, the entire disclosure of which is incorporated herein by reference.

[0002] (Field of the Invention) This disclosure relates to the protection of lithium - ion batteries from thermal events, including fire extinguishment of flames and cessation of thermal runaway.

Background Art

[0003] Gas - based clean - agent fire suppressants such as FM - 200™ (HFC - 227ea, 1,1,1,2,3,3,3 - heptafluoropropane) and Novec™ 1230 (FK - 5 - 1 - 12, perfluoroethyl isopropyl ketone) are generally accepted within the specialty fire - suppression industry as being unable to stop the thermal runaway, particularly cascading thermal runaway, associated with lithium - ion battery (LIB) fires in currently available methods and systems, and being limited only to extinguishing liquid - electrolyte fires associated with LIBs. For example, Ingram discloses in "Lithium - Ion Batteries: A Potential Fire Hazard" (Data Center Journal, 2013) that "Gaseous agents will extinguish flames due to burning leaked electrolyte but have little or no effect on mitigating or preventing a thermal runaway occurring within Li - ion cells." More recently, Ingram disclosed in "Fire Suppression for Lithium Ion Battery Fires," presented at the 2019 annual conference of the Fire Suppression System Association, that "thermal runaway cannot be controlled by any suppression system."

[0004] U.S. Patent Application Publication 2010 / 0078182 discloses a device for generating and storing electrical or mechanical energy, such as a fuel cell, a conventional battery, or a rechargeable battery, and a method for fire prevention. At least one element of the device that generates or stores electrical or mechanical energy is located within an enclosure. A container for storing flame-retardant material is in contact with the enclosure. If multiple cells are present, the system does not separate the cells from each other to prevent damage to other cells. Furthermore, the system does not have a method for operating in the presence of an open flame. U.S. Patent Application Publication 2010 / 0078182 describes extinguishing flames but does not address stopping thermal runaway.

[0005] Chinese Patent Application Publication No. 206167681 discloses a device for protecting lithium-ion batteries in automobiles from fire, which involves the use of a fire detection / delivery tube placed inside the battery case enclosing the battery. The extinguishing agent can be heptafluoropropane. A pressure signal sensor is installed in the extinguishing agent delivery / fire detection tube inside the battery case. While Chinese Patent Application Publication No. 206167681 describes fire suppression, it does not address the cessation of thermal runaway.

[0006] U.S. Patent No. 7,823,650 discloses a hazard control system for delivering a fire extinguishing agent in response to the detection of a hazard such as a fire. The system may use a pressure pipe configured to leak in response to exposure to heat. The elements of the system include (1) a control unit, (2) a fire extinguishing agent, (3) a hazard detection system, (4) a hazard area, and (5) a delivery system for delivering the fire extinguishing agent to the hazard area. The hazard detection system generates a signal in response to the detection of a hazard, such as a change in pressure in the pressure pipe. While U.S. Patent No. 7,823,650 describes a fire control system, it does not address how to extinguish a fire or stop a thermal runaway. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] U.S. Patent Provisional Application No. 63 / 107,052 [Patent Document 2] U.S. Patent Application Publication No. 2010 / 0078182 [Patent Document 3] Chinese Patent Application Publication No. 206167681 [Patent Document 4] U.S. Patent No. 7823650 [Overview of the project] [Problems that the invention aims to solve]

[0008] The need to address thermal protection requirements associated with lithium-ion batteries remains, including stopping thermal runaway, extinguishing flames, and preventing re-ignition of extinguished fires. This invention satisfies these requirements. [Means for solving the problem]

[0009] This disclosure provides a method for extinguishing a flame and stopping thermal runaway in a device powered by a lithium-ion battery. The method includes (a) providing a housing; (b) providing a device disposed within the housing, the device comprising and powered by a lithium-ion battery; (c) providing a source of a thermal runaway deterrent, the source including a container and a two-way control valve, the container containing the thermal runaway deterrent, the two-way control valve being attached to an opening in the container, and the thermal runaway deterrent containing HFC-227ea; and (d) providing a temperature sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, the tube having two ends, (i) one end communicating with the two-way control valve and the other end being covered, and (ii) the tube being located within the housing and sensing a threshold temperature. The device includes (iii) a temperature sensor for the purpose of (iii) positioning a tube in close proximity to a lithium-ion battery, and (e) providing a thermal stimulus that generates a flame and initiates thermal runaway, wherein when the temperature sensor tube ruptures, an opening ("thermal stimulus forming opening") is formed in the temperature sensor tube, and an inert gas or thermal runaway arrestant inside the temperature sensor tube is released into the housing through the thermal stimulus forming opening of the temperature sensor tube, resulting in a decrease in the pressure inside the temperature sensor tube, which activates a two-way control valve to deliver a thermal runaway arrestant from a storage container to the temperature sensor tube through the two-way control valve, and delivers it out of the thermal stimulus forming opening of the temperature sensor tube into the housing, wherein the delivery of the thermal runaway arrestant is characterized by a release time, a thermal runaway arrestant concentration, and a retention time, thereby extinguishing the flame, stopping the thermal runaway, and preventing re-ignition after the flame has been extinguished.

[0010] Furthermore, a method is provided for extinguishing a flame and stopping thermal runaway in a device powered by a lithium-ion battery, the method comprising: (a) providing a housing; (b) providing a device disposed within the housing, the device comprising and powered by a lithium-ion battery; (c) providing a source of a thermal runaway deterrent, the source comprising a container and a three-way control valve, the container containing the thermal runaway deterrent, the three-way control valve being attached to the opening of the container, and the thermal runaway deterrent comprising HFC-227ea; and (d) providing a temperature sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, the tube having two ends, (i) one end communicating with the three-way control valve and the other end being covered; and (ii) the tube being located within the housing and a temperature sensing tube for detecting a threshold temperature. The device comprises the steps of: (iii) a tube positioned in close proximity to a lithium-ion battery; (e) a nozzle connecting tube communicating with a three-way control valve at one end and terminating at the other end with a nozzle in close proximity to the lithium-ion battery; and (f) a thermal stimulus that generates a flame and initiates thermal runaway, wherein when the temperature-sensing tube ruptures, an opening ("thermal stimulus forming opening") is formed in the temperature-sensing tube, and an inert gas or thermal runaway inhibitor inside the temperature-sensing tube is released into the housing through the thermal stimulus forming opening of the temperature-sensing tube, resulting in a decrease in the pressure inside the temperature-sensing tube, which activates the three-way control valve to deliver the thermal runaway inhibitor from the storage container through the three-way control valve to the nozzle connecting tube, thereby releasing the thermal runaway inhibitor from the nozzle into the housing, wherein the delivery of the thermal runaway inhibitor is characterized by the release time, the concentration of the thermal runaway inhibitor, and the retention time, thereby extinguishing the flame, stopping the thermal runaway, and preventing re-ignition after the flame has been extinguished.

[0011] The concentration, release time, and retention time of the thermal runaway arrestant within the enclosure offer the following advantages over existing systems: (1) extinguishing flames once they occur, (2) stopping thermal runaway occurring in single-cell lithium-ion batteries, multi-cell lithium-ion batteries, or lithium-ion battery banks, and (3) preventing re-ignition after the flames have been extinguished.

[0012] Furthermore, a fire protection system is provided, which comprises (a) a housing; (b) a device located within the housing, comprising a lithium-ion battery and powered by the lithium-ion battery; (c) a source of thermal runaway deterrent, comprising a container and a two-way control valve, wherein the container contains the thermal runaway deterrent, the two-way control valve is attached to the opening of the container, and the thermal runaway deterrent contains HFC-227ea; and (d) a temperature sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, wherein the tube has two ends, (i) one end communicating with the two-way control valve and the other end covered, (ii) the tube is located within the housing and comprises a temperature sensor for detecting a threshold temperature, and (iii) the tube is located in close proximity to the lithium-ion battery and is capable of rupturing when it senses a threshold temperature.

[0013] Furthermore, a fire protection system is provided, which includes (a) a housing, (b) a device located within the housing, equipped with a lithium-ion battery and powered by the lithium-ion battery, (c) a thermal runaway arrestor source, comprising a container and a three-way control valve, the container containing the thermal runaway arrestor, the three-way control valve being attached to the opening of the container, and the thermal runaway arrestor containing HFC-227ea, and (d) a predetermined pressure and temperature suitable for the normal operating conditions of the device. A temperature sensing tube for containing an inert gas or thermal runaway arresting agent, having two ends, (i) one end communicating with a three-way control valve and the other end covered, (ii) the temperature sensing tube is located inside the housing and is equipped with a temperature sensor for detecting a threshold temperature, (iii) the temperature sensing tube is positioned close to a lithium-ion battery and is capable of rupturing when the temperature sensing tube senses a threshold temperature, and (e) a nozzle connecting tube which communicates with a three-way control valve at one end and terminates at the other end with a nozzle close to a lithium-ion battery.

[0014] Other features will be apparent to those skilled in the art based on this disclosure.

[0015] The present disclosure addresses the problem of lithium-ion batteries where a fire extinguishing agent cannot stop thermal runaway and no suppression system can stop thermal runaway. By selecting a specific thermal runaway inhibitor and administering the agent at a specific concentration and retention time over a specific release time within a device powered by a lithium-ion battery, not only is the fire in the device extinguished (initial fire extinguishing), but thermal runaway is stopped and re-ignition after initial fire extinguishing of the fire is prevented.

Brief Description of the Drawings

[0016] [Figure 1a] It is a diagram of one embodiment of the LIB protection system of the present disclosure. [Figure 1b] It is a diagram of one embodiment of the LIB protection system of the present disclosure. [Figure 2] It is a diagram of a second embodiment of the LIB protection system of the present disclosure. [Figure 3] It is a diagram of a third embodiment of the LIB protection system of the present disclosure. [Figure 4] It is a diagram of a fourth embodiment of the LIB protection system of the present disclosure. [Figure 5] It is a diagram of a typical lithium-ion battery (LIB).

Modes for Carrying Out the Invention

[0017] Method for extinguishing a fire and stopping thermal runaway Embodiment 1 In certain embodiments of the present disclosure, a method for extinguishing a fire and stopping thermal runaway in a device is provided. The method includes: (a) providing a housing; (b) providing a device disposed within the housing, the device comprising a lithium-ion battery and being powered by the lithium-ion battery; (c) providing a source of a thermal runaway inhibitor, the source including a container and a two-way control valve, the container containing the thermal runaway inhibitor, the two-way control valve being attached to an opening of the container, and the thermal runaway inhibitor including HFC-227ea; (d) providing a temperature-sensitive tube containing an inert gas or a thermal runaway inhibitor at a predetermined pressure and temperature suitable for normal operating conditions of the device, the tube having two ends, (i) one end communicating with the two-way control valve and the other end being covered, (ii) the tube being located within the housing and including a temperature sensor for detecting a threshold temperature, and (iii) the tube being disposed in proximity to the lithium-ion battery; and (e) providing a thermal stimulus that generates a fire and initiates thermal runaway, such that when the temperature-sensitive tube ruptures, an opening (thermal stimulus formation opening) is formed in the tube, and the inert gas or thermal runaway inhibitor within the temperature-sensitive tube is released into the housing through the thermal stimulus formation opening of the temperature-sensitive tube, as a result of which the pressure within the temperature-sensitive tube decreases, actuating the two-way control valve to deliver the thermal runaway inhibitor from the storage container through the two-way control valve to the temperature-sensitive tube and out of the thermal stimulus formation opening of the temperature-sensitive tube into the housing. The delivery of the thermal runaway inhibitor is characterized by a release time, a thermal runaway inhibitor concentration, and a hold time, thereby extinguishing the fire, stopping the thermal runaway, and preventing re-ignition after the fire is extinguished.

[0018] The two-way control valve is in sensor communication with the temperature-sensitive tube. In this embodiment, the temperature-sensitive tube is in fluid communication with the source through the two-way control valve such that when the two-way control valve is actuated, the thermal runaway inhibitor is delivered to the temperature-sensitive tube. In this embodiment, the temperature-sensitive tube functions to detect the thermal stimulus and deliver the thermal runaway inhibitor into the housing.

[0019] In one method of Embodiment 1, in step (d), the temperature-sensitive tube contains an inert gas. In another method of Embodiment 1, in step (d), the temperature-sensitive tube contains a thermal runaway inhibitor.

[0020] Embodiment 2 Furthermore, a method is provided for extinguishing a flame and preventing thermal runaway in a device powered by a lithium-ion battery, the method comprising: (a) providing a housing; (b) providing a device disposed within the housing, the device comprising a lithium-ion battery and powered by a lithium-ion battery; (c) providing a source of a thermal runaway deterrent, the source comprising a container and a three-way control valve, the container containing the thermal runaway deterrent, the three-way control valve being attached to the opening of the container, and the thermal runaway deterrent comprising HFC-227ea; and (d) providing a temperature-sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, the temperature-sensing tube having two ends, (i) one end communicating with the three-way control valve and the other end being covered; and (ii) the temperature-sensing tube being disposed within the housing and a temperature sensor for detecting a threshold temperature. The device comprises the steps of: (iii) providing a temperature-sensing tube positioned close to a lithium-ion battery; (e) providing a nozzle connecting tube communicating with a three-way control valve at one end and terminating at the other end with a nozzle close to a lithium-ion battery; and (f) providing a thermal stimulus that generates a flame and initiates thermal runaway, wherein when the temperature-sensing tube ruptures, an opening ("thermal stimulus forming opening") is formed in the temperature-sensing tube, and an inert gas or thermal runaway inhibitor inside the temperature-sensing tube is released into the housing through the thermal stimulus forming opening of the temperature-sensing tube, resulting in a decrease in the pressure inside the temperature-sensing tube, which activates the three-way control valve to deliver the thermal runaway inhibitor from a storage container through the three-way control valve to the nozzle connecting tube, thereby releasing the thermal runaway inhibitor from the nozzle into the housing, wherein the delivery of the thermal runaway inhibitor is characterized by the release time, the concentration of the thermal runaway inhibitor, and the retention time, thereby extinguishing the flame, stopping the thermal runaway, and preventing re-ignition after the flame has been extinguished.

[0021] The three-way control valve communicates with the temperature-sensing tube. In this embodiment, the temperature-sensing tube is in fluid communication with the supply source, and when the three-way control valve is activated, the thermal runaway arrestant is delivered through a nozzle connecting tube that terminates at a nozzle adjacent to the lithium-ion battery, and the thermal runaway arrestant is released into the housing through the nozzle. In this embodiment, the temperature-sensing tube acts to detect thermal stimulation, and the nozzle connecting tube acts to deliver the thermal runaway arrestant into the housing.

[0022] In one method of Embodiment 2, in step (d), the temperature-sensing tube contains an inert gas. In an alternative method of Embodiment 2, in step (d), the temperature-sensing tube contains a thermal runaway arrester.

[0023] Fire protection system for lithium-ion batteries Embodiment 3 In certain embodiments of the present disclosure, a fire protection system is provided, the fire protection system comprising: (a) a housing; (b) a device disposed within the housing, comprising a lithium-ion battery and powered by the lithium-ion battery; (c) a source of a thermal runaway deterrent, the source comprising a container and a two-way control valve, the container containing the thermal runaway deterrent, the two-way control valve being attached to the opening of the container, and the thermal runaway deterrent comprising HFC-227ea; and (c) a temperature sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, the tube having two ends, (i) one end communicating with the two-way control valve and the other end covered, (ii) the tube disposed within the housing and comprising a temperature sensor for detecting a threshold temperature, and (iii) the temperature sensing tube being disposed in close proximity to the lithium-ion battery and capable of rupturing when the temperature sensing tube senses a threshold temperature.

[0024] In this embodiment, the two-way control valve communicates with the temperature-sensing tube. Furthermore, in this embodiment, the temperature-sensing tube is in fluid communication with a supply source so that a thermal runaway prevention agent is delivered to the temperature-sensing tube when the two-way control valve is activated. In this embodiment, the temperature-sensing tube detects thermal stimulation and acts to deliver the thermal runaway prevention agent into the housing.

[0025] In one fire protection system of Embodiment 3, the temperature-sensing tube of component (c) contains an inert gas. In an alternative fire protection system of Embodiment 3, the temperature-sensing tube of component (c) contains a thermal runaway arresting agent.

[0026] Embodiment 4 Furthermore, a fire protection system is provided, which includes (a) a housing, (b) a device located within the housing, equipped with a lithium-ion battery and powered by the lithium-ion battery, (c) a thermal runaway arrestor source, the source including a container and a three-way control valve, the container containing the thermal runaway arrestor, the three-way control valve being attached to the opening of the container, and the thermal runaway arrestor containing HFC-227ea, and (d) a predetermined pressure and temperature suitable for the normal operating conditions of the device. A temperature sensing tube for containing an inert gas or thermal runaway arrestor at a temperature of 10 degrees, wherein the tube has two ends, (i) one end communicating with a three-way control valve and the other end covered, (ii) the tube is placed inside a housing and equipped with a temperature sensor for detecting a threshold temperature, (iii) the temperature sensing tube is placed in close proximity to a lithium-ion battery and is capable of rupturing when the temperature sensing tube senses a threshold temperature, and (e) a nozzle connecting tube which communicates with a three-way control valve at one end and terminates at the other end with a nozzle in close proximity to a lithium-ion battery.

[0027] In this embodiment, the three-way control valve communicates with the temperature-sensing tube. Furthermore, in this embodiment, the three-way control valve is in fluid communication with the nozzle connecting tube so that when the three-way control valve is activated, the thermal runaway arrestant is delivered to the nozzle connecting tube. In this embodiment, the temperature-sensing tube functions as a temperature sensor and an actuator or activation (startup) device for the three-way control valve, but does not function as a delivery tube for the thermal runaway arrestant into the housing. In this embodiment, the nozzle connecting tube functions as a delivery tube.

[0028] In one fire protection system according to Embodiment 4, the temperature-sensing tube of component (c) contains an inert gas. In an alternative fire protection system according to Embodiment 4, the temperature-sensing tube of component (c) contains a thermal runaway arresting agent.

[0029] The terms used in this specification in a specific sense are listed below.

[0030] In this specification, "sensor communication" means that a control valve can receive a signal generated by a temperature-sensing tube, thereby activating the control valve to open the container and release the thermal runaway inhibitor from the container. Depending on the embodiment, the control valve may be a two-way or three-way control valve. The signal may be, for example, pneumatic or electronic.

[0031] In embodiments 1 and 3, the two-way control valve communicates with the temperature-sensing tube and the sensor. In embodiments 2 and 4, the three-way control valve communicates with the temperature-sensing tube and the sensor.

[0032] As used herein, a two-way control valve is a control valve having at least two ports. Therefore, those skilled in the art will understand that a two-way control valve may have three or more ports. In embodiments 1 and 3, however, the term "two-way control valve" includes control valves having at least three ports. For example, a two-way control valve having a third port may be used, in which case the third port provides an option for taking a sample of the container contents.

[0033] Similarly, a three-way control valve is a control valve having at least three ports. Therefore, it will be understood by those skilled in the art that a three-way control valve may have four or more ports. In embodiments 2 and 4, the term "three-way control valve" means that it includes a control valve having at least four ports. For example, a three-way control valve having a fourth port may be used, in which case the fourth port provides an option for taking a sample of the contents of the container.

[0034] "Fluid communication" means that a fluid can flow from the container through the control valve to either the temperature-sensing tube or the nozzle connection tube without being interrupted.

[0035] In embodiments 1 and 3, the two-way control valve is in fluid communication with the container and the temperature sensing tube. In embodiments 2 and 4, the three-way control valve is in fluid communication with the container and the nozzle connecting tube.

[0036] More specifically, in Embodiment 1, the rupture of the temperature-sensing tube in step (e) results in a flow from the thermal runaway arrestor container through the two-way control valve to the temperature-sensing tube and into the housing. More specifically, in Embodiment 2, the rupture of the temperature-sensing tube in step (f) results in a flow from the thermal runaway arrestor container through the three-way control valve to the nozzle connecting tube and into the housing through the nozzle adjacent to the lithium-ion battery.

[0037] Sensor communication and fluid communication are performed regardless of whether the power source is located inside or outside the enclosure.

[0038] device A device powered by a lithium-ion battery is any device powered by one or more lithium-ion batteries. Examples of lithium-ion battery-powered devices suitable for the methods and systems disclosed herein include data loggers, telecommunications equipment, personal electronic devices, power tools, energy storage systems, data centers, electric vehicles, and electric bicycles. Personal electronic devices include mobile phones, laptop computers, and gaming systems.

[0039] battery As used herein, “battery” means a container containing at least one cell into which chemical energy is converted into electricity and used as a power source. A “cell” includes a single anode and cathode separated by an electrolyte used to generate voltage and current. In a “battery bank” or “battery pack,” two or more batteries may be arranged in parallel, in series, or in a combination of both if there are three or more batteries.

[0040] Lithium-ion battery As used herein, "lithium-ion battery" or "LIB" means a battery that utilizes lithium-ion chemistry and includes an electrolytic cell having a lithium salt electrolyte. A lithium-ion battery may be a single-cell battery, a multi-cell battery, or a battery bank containing two or more lithium-ion batteries.

[0041] A lithium-ion battery (LIB) comprises an anode chamber containing an anode, a cathode chamber containing a cathode, and a semipermeable membrane separating the anode chamber from the cathode chamber. The anode is made of graphite protected by a solid electrolyte interface (SEI) layer. The cathode is made of a lithium metal oxide such as LiCoO2, LiFePO4, LiMn2O4, or LiNiMnCoO2. The anode chamber and cathode chamber are each filled with a liquid electrolyte. The liquid electrolyte is typically a flammable organic carbonate such as ethylene carbonate or diethyl carbonate. The liquid electrolyte contains lithium salts such as LiPF6, LiAsF6, LiClO4, LiBF4, and LiCF3SO3.

[0042] cabinet The lithium-ion battery device is housed within a housing. The housing is constructed of materials capable of withstanding temperatures and pressures sufficient to contain any flames generated by the battery. The housing forms a physical barrier between the LIB device and the surrounding area.

[0043] Source of thermal runaway deactivation agent A source for a thermal runaway arrester is provided. The source includes a storage container for storing the thermal runaway arrester during normal operation. The source further comprises a control valve attached to the container. Depending on the embodiment, the control valve may be a two-way control valve or a three-way control valve.

[0044] In any of the embodiments disclosed herein, the power source may be located within the housing.

[0045] Alternatively, in any of the embodiments disclosed herein, the supply source may be located outside the housing. In such embodiments, the housing has an opening that provides sensor communication between the temperature-sensing tube and the control valve. If this embodiment is Embodiment 1 or Embodiment 3, the housing also has an opening that provides fluid communication between the two-way control valve and the temperature-sensing tube for delivering the thermal runaway arrestor into the housing. If this embodiment is Embodiment 2 or Embodiment 4, the housing also has an opening that provides fluid communication between the three-way control valve and the nozzle connecting tube. The openings for sensor communication and fluid communication within the housing are sealed to maintain the integrity of the housing in the event of thermal stimulation.

[0046] Control valve In certain embodiments, including Embodiments 1 and 3, if the temperature-sensing tube ruptures due to excessive heat caused by flames from a LIB fire, a two-way control valve allows a thermal runaway arrestor to be released from the container through the temperature-sensing tube into the housing.

[0047] The two-way control valve communicates with the temperature-sensing tube. The two-way control valve can be any type of valve that receives a signal from the temperature-sensing tube and is activated by that signal. The signal is generated in the temperature-sensing tube when it ruptures due to thermal stimulation. When activated, the two-way control valve opens the fluid connection from the container through the valve to the temperature-sensing tube, delivering a thermal runaway arrestor to the vicinity of the lithium-ion battery.

[0048] In such embodiments, the thermal runaway arrestant is delivered into the housing through a thermal stimulation forming opening in the temperature-sensing tube. In such embodiments, the two-way control valve communicates with the temperature-sensing tube and fluid.

[0049] In certain embodiments, including Embodiments 2 and 4, if the temperature-sensing tube ruptures due to excessive heat caused by flames from a LIB fire, the three-way control valve allows a thermal runaway arrestor to be released from the container through the valve to the nozzle connecting pipe and into the housing.

[0050] The three-way control valve communicates with a temperature-sensing tube. The three-way control valve can be any type of valve that can receive a signal from the temperature-sensing tube and be activated by that signal. The signal is generated in the temperature-sensing tube when it ruptures due to thermal stimulation. When activated, the three-way control valve opens fluid communication from the container through the valve to the nozzle connecting tube, delivering a thermal runaway arrestor through the nozzle adjacent to the lithium-ion battery.

[0051] In such embodiments, the thermal runaway arrestant is delivered into the housing through a nozzle connecting tube. In such embodiments, the three-way control valve communicates with a temperature sensing tube and is in fluid communication with the nozzle connecting tube.

[0052] inert gas The inert gases used herein include gases selected from nitrogen, argon, helium, carbon dioxide, and mixtures thereof. Optionally, the inert gas may further include a thermal runaway arrestor.

[0053] Thermal runaway deactivator The thermal runaway arrestor comprises a sufficient amount of HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane or simply HFC-227ea) to provide a concentration of at least 17% v / v (volume / volume) of HFC-227ea when delivered to the enclosure. In a preferred embodiment, the thermal runaway arrestor comprises a sufficient amount of HFC-227ea to provide a concentration of at least 20% v / v of HFC-227ea when delivered to the enclosure.

[0054] The thermal runaway arrester may further include one or more inert gases. The inert gases may be selected from nitrogen, argon, helium, carbon dioxide, and mixtures thereof.

[0055] The total pressure of the HFC-227ea / inert gas mixture is preferably 120-600 psig at 70°F (0.8-4 MPa at 21°C). Higher pressures may be used, and the upper limit is based primarily on practicality, among other reasons.

[0056] The thermal runaway arrester may further contain one or more halocarbon gases. The halocarbon gas may be selected from pentafluoroethane (HFC-125), iodotrifluoromethane (CF3I), trifluoromethane (CF3H), 1,1,1,3,3,3-hexafluoroethane (HFC-236fa), E- or Z-1-chloro-3,3,3-trifluoropropene (E- or Z-HCFO-1233zd), E- or Z-1,3,3,3-tetrafluoropropene (E- or Z-HFO-1234ze), E- or Z-1-chloro-2,3,3,3-tetrafluoropropene (E or Z-1224yd), or perfluoroethylperfluoroisopropyl ketone (FK-5-1-12, (CF3)2CFC(O)CF2CF3).

[0057] temperature sensitive tube The thermosensing tube is housed within the casing. The thermosensing tube is a pressure tube, meaning it contains or is filled with an inert gas or thermal runaway arrestor at a predetermined pressure. Thermosensing tubes are commercially available, for example, from Rotarex in Luxembourg.

[0058] The predetermined pressure supplied to the inert gas or thermal runaway arrester within the temperature-sensing tube may be varied to produce different tube rupture temperatures. Higher pressure results in tube rupture at a lower temperature, while lower pressure results in tube rupture at a higher temperature.

[0059] "Tube rupture" means that the pressure of the inert gas or thermal runaway arrester inside the tube increases, causing the tube to rupture when a thermal stimulus occurs. In other words, a temperature-sensing tube is "potentially ruptured" when it senses a threshold temperature.

[0060] The threshold temperature is the temperature at which the thermosensing tube ruptures. The threshold temperature is determined by a predetermined pressure applied to the inert gas or thermal runaway arrester within the thermosensing tube, and based on the specific composition of the thermosensing tube. That is, by changing the detailed composition of the thermosensing tube, different threshold temperatures for tube rupture can be provided.

[0061] As will be further described below in this specification, thermal stimulation may be the result of heat applied to the housing from an external or internal heat source.

[0062] An external heat source is any heat source that is physically located outside the enclosure, such as a high-temperature engine or an external flame.

[0063] The internal heat source may be the LIB itself, or it may be overheating caused by a mechanical, electrical, or faulty event, which generates heat within the enclosure. Further information is provided below.

[0064] When the tube ruptures, it releases the inert gas or thermal runaway arrestor that was previously contained inside. Furthermore, a person skilled in the art will understand that when the tube ruptures, the inert gas or thermal runaway arrestor inside the temperature-sensing tube is released into the housing.

[0065] The thermosensing tube is positioned close to the lithium-ion battery within the device housing so that the heat released from a thermal stimulus causes the tube to rupture.

[0066] When a temperature-sensing tube ruptures, an opening is formed in the tube, and the inert gas or thermal runaway prevention agent that was normally maintained inside the tube during operation is released into the housing. The rupture also generates a signal, for example, from the pressure loss inside the temperature-sensing tube, which is relayed to the control valve.

[0067] In Embodiment 1, the signal activates a two-way control valve, releasing a thermal runaway arrestor from the storage container through the two-way control valve into the temperature-sensing tube and out through the thermal stimulation-forming opening of the temperature-sensing tube, thereby extinguishing the flame and stopping the thermal runaway, and preventing re-ignition after the initial extinguishing of the flame. In this embodiment, the temperature-sensing tube functions as a temperature sensor, an actuator or operating device for the two-way control valve, and a delivery tube for delivering the thermal runaway arrestor into the housing.

[0068] In Embodiment 2, the signal generated by the rupture of the tube is relayed to a three-way control valve, which activates the valve to release the thermal runaway arrestor from the container through the valve to the nozzle connecting tube. The nozzle connecting tube is separated from the temperature sensing tube. In this embodiment, the nozzle connecting tube has a nozzle at its distal end from the three-way control valve inside the housing. In this embodiment, the temperature sensing tube functions as a temperature sensor and an actuator or an operating device for the three-way control valve, but does not function as a delivery tube for the thermal runaway arrestor into the housing. In this embodiment, the nozzle connecting tube functions as a delivery tube.

[0069] Normal operating conditions "Normal operating conditions" in this specification means that the device powered by the lithium-ion battery is operating under conditions of temperature, pressure, and environmental factors that do not cause the temperature sensor tube to burst.

[0070] thermal stimulation A thermal stimulus is an event that causes heat generation within the enclosure, such as when a LIB ignites, resulting in flames and thermal runaway within the device. A thermal stimulus can be a mechanical, thermal, electrical, or defect event.

[0071] A typical description of LIB thermal runaway events can be found in Chapter 3.9.3 of "Lithium-Ion Battery Chemistries" by John T. Warner [Elsevier 2019]. While the exact temperatures shown in this description are not precise, as they depend on the cell design and chemical properties, it will be understood by those skilled in the art that the sequence of events involved in thermal runaway is similar for different LIB designs, as described below.

[0072] Thermal runaway occurs when the temperature inside a LIB cell rises above the normal operating temperature, resulting in the initiation of a chain reaction within the cell that automatically continues due to uncontrolled temperature rise and oxygen generation.

[0073] According to Warner, when the cell temperature reaches approximately 80°C, the protective solid electrolyte interface (SEI) layer on the anode begins to decompose in an exothermic reaction (generating heat) between lithium and the electrolyte solvent. At approximately 100°C–120°C, the electrolyte (typically a flammable organic carbonate) begins to decompose in another exothermic reaction, subsequently generating various gases such as CO2 and hydrocarbons within the cell. As the temperature approaches 120°C–130°C, the separator between the anode and cathode melts, allowing contact between the anode and cathode, causing an internal short circuit and generating even more heat. As the temperature continues to rise, at approximately 130°C–150°C, the cathode begins to decompose in another exothermic chemical reaction with the electrolyte, also generating oxygen.

[0074] The release of oxygen from the cathode's dielectric breakdown and its contact with the flammable electrolyte causes a fire (flame) within the cell. Cathode dielectric breakdown is also a highly exothermic reaction that generates a considerable amount of heat, continuing to drive the cell toward eventual failure and further intensifying the fire within the cell.

[0075] If the temperature rises above 150°C to 180°C, and the cell cannot rapidly dissipate the heat it has generated, the chain reaction may automatically continue. At this point, the cell is in a state called "thermal runaway" as the temperature rises, and oxygen generation automatically continues the fire. If gas continues to accumulate inside the cell, the cell may rupture or the gas may be released through a safety valve. At this point, the cell may rupture or release the flammable hydrocarbon gas and hydrofluorocarbon electrolyte. Introducing a spark may ignite the electrolyte and gas, causing flames, fire, and potentially an explosion.

[0076] "Mechanical events" refer to physical damage to the LIB, such as penetration by a sharp or blunt object, crushing by a heavy object, or collision with a car.

[0077] A "thermal event" means that the LIB is exposed to a temperature that causes the LIB to degrade. The source of the temperature can be internal, such as a loose connection that causes the LIB to overheat from the inside, or external, such as a nearby heat source, an external flame, or loss of environmental control within the environmental control area.

[0078] "Electrical event" means that the LIB experiences a problem that disrupts or interrupts the normal flow of electrons through the LIB, such as a short circuit or overcharge.

[0079] A "defective event" means that the design or manufacture of the LIB (e.g., inadequate quality control, insufficient insulation, loose connections) introduces a defect that prevents the LIB from protecting itself from short circuits or overheating during normal operation.

[0080] Two or more mechanical, thermal, electrical, or defect events can combine to cause a thermal stimulus. For example, in one embodiment, a short circuit (electrical event) may cause the LIB to overheat (thermal event), resulting in a combined event as a thermal stimulus. In another embodiment, a mechanical event such as a puncture or through-hole in the LIB may cause a short circuit (electrical event) leading to rapid heating (thermal event) as a thermal stimulus. In yet another embodiment, a loose connection (defect event) may lead to overheating (thermal event) as a thermal stimulus. The embodiments described above are merely examples and are not intended to be exhaustive.

[0081] When thermal stimulation occurs, the temperature-sensing tube may rupture, releasing an inert gas or thermal runaway arrester into the housing.

[0082] Thermal runaway arresters are released at specified release times, concentrations, and retention times to stop both flames and thermal runaway, and to prevent re-ignition after initial flame extinguishing. Generally accepted definitions of agent concentration, release time, and retention time are understood by those skilled in the art, as provided in the NFPA 2001 standard for Clean Agent Fire Protection Systems, available at https: / / www.nfpa.org / codes-and-standards / all-codes-and-standards / list-of-codes-and-standards / detail?code=2001.

[0083] The thermal runaway arrestor is released into the enclosure at a specified release time, concentration, and retention time, each sufficient to extinguish any existing flames and to stop the thermal runaway. The release of the thermal runaway arrestor is also provided with a retention time sufficient to cool the enclosure and LIB to a temperature sufficient to prevent re-ignition.

[0084] In a preferred embodiment, the thermal runaway arrestor contains an amount of HFC-227ea sufficient to provide a concentration of 17% to 30% v / v when delivered to the housing. In another embodiment, the thermal runaway arrestor contains an amount of HFC-227ea sufficient to provide a concentration of 18% to 28% v / v. In yet another embodiment, the thermal runaway arrestor contains an amount of HFC-227ea sufficient to provide a concentration of 20% to 23% v / v.

[0085] In preferred embodiments, the release time is in the range of 18 to 180 seconds, or 25 to 120 seconds, and / or 45 to 120 seconds. “Release time” as used herein means the time from the start of drug delivery into the housing to the time when 95% of the drug has been delivered into the housing.

[0086] In preferred embodiments, the holding time is in the range of 10 to 15 minutes, 15 to 30 minutes, or 30 to 60 minutes. “Holding time” as used herein means the period during which the concentration of the agent in the housing remains at the desired concentration (over time, the agent may slowly leak out through small openings in the housing, such as holes or ventilation holes).

[0087] In one embodiment, the release time is at least 18 seconds, and the thermal runaway arrestor contains a sufficient amount of HFC-227ea to provide a concentration of at least 17% v / v of HFC-227ea, providing sufficient cooling to extinguish the flame, stop thermal runaway in a single or multiple cell configuration, and prevent re-ignition. Longer release times and higher concentrations may be used, and the upper limits are based particularly on practicality among other reasons.

[0088] Detailed description of the drawing Figures 1a and 1b illustrate a LIB protection system disclosed herein, used in a method for extinguishing flames and stopping thermal runaway in a device powered by a lithium-ion battery disclosed herein. The housing 101 is a hazardous area that may experience a lithium-ion battery fire originating from a LIB 102 located within a lithium-ion battery (LIB) device 103. The LIB fire protection system includes a thermal runaway arrestor supply source 104, which includes a thermal runaway arrestor container 105 and a two-way control valve 106 connected to the thermal runaway arrestor container 105 and a temperature-sensing tube 107. The temperature-sensing tube 107 has an end sealed via a tube end seal 108. The temperature-sensing tube 107 is pressurized to a desired pressure with an inert gas or thermal runaway arrestor. In the case of a flame 109 generated from the LIB-type device 103, the portion of the temperature-sensing tube 107 where the maximum heat (threshold temperature) is detected ruptures (see Figure 1b), forming a thermal stimulation opening 110. This releases an inert gas or thermal runaway arrester from inside the temperature-sensing tube 107 into the housing 101, simultaneously causing a pressure drop inside the temperature-sensing tube 107. This pressure drop activates the control valve 106, delivering the thermal runaway arrester from the thermal runaway arrester storage container 105 through the control valve 106 into the temperature-sensing tube 107. The arrester then exits through the thermal stimulation opening 110 (see Figure 1b) and is delivered to the temperature-sensing tube 107 and into the housing 101. The release of the thermal runaway arrester into the housing 101 extinguishes the flame and stops the thermal runaway in the LIB-type device 103, preventing re-ignition after the initial extinguishing of the flame.

[0089] Figure 1b is the same as Figure 1a, but in Figure 1b, the temperature-sensing tube 107 has ruptured due to the flame 109, and the thermal stimulation-forming opening 110 is visible.

[0090] In the LIB fire protection system shown in Figures 1a and 1b, the temperature sensing tube 107 functions as a temperature sensor (which can also be considered a fire detection device), an actuator or operating device for a two-way control valve (which can also be considered a system activation device), and a delivery tube for delivering a thermal runaway prevention agent into the housing.

[0091] Figure 2 is a diagram of a LIB protection system disclosed herein, used in a method for extinguishing flames and stopping thermal runaway in a lithium-ion battery-powered device disclosed herein. The housing 201 is a hazardous area that may experience a LIB fire originating from a LIB 202 located inside a lithium-ion battery (LIB) device 203. The LIB fire protection system includes a thermal runaway arrestor supply source 204 comprising a thermal runaway arrestor container 205 and a three-way control valve 206 connected to the thermal runaway arrestor container 205 and a temperature-sensing tube 207, the end of which is sealed via a tube end seal 208. The temperature-sensing tube 207 is pressurized to a desired pressure with an inert gas or thermal runaway arrestor. A nozzle connecting tube 211 is connected to the three-way control valve 206 and terminates at a delivery nozzle 212. In the event of a fire occurring in the LIB-type device 203, the portion of the temperature-sensing tube 207 that detects the maximum heat (threshold temperature) ruptures, releasing the inert gas or thermal runaway arrestant inside the temperature-sensing tube 207 into the housing 201. Simultaneously, this causes a pressure drop inside the temperature-sensing tube 207, which activates the three-way control valve 206, diverting the flow from the temperature-sensing tube 207 to the nozzle connection pipe 211. The thermal runaway arrestant is then delivered from the thermal runaway arrestant storage container 205 through the three-way control valve 206 into the nozzle connection pipe 211, and then delivered to the outside through the delivery nozzle 212. The release of the thermal runaway arrestant into the housing 201 extinguishes the flame and stops the thermal runaway in the LIB-type device 203, preventing re-ignition after the initial extinguishing of the flame.

[0092] In the LIB fire protection system shown in Figure 2, the temperature sensing tube 207 functions as a temperature sensor (which can also be considered a fire detection device) and as an actuator or activation device for the control valve 206 (which can also be considered a system activation device), but it does not function as a delivery tube for delivering the thermal runaway arrestant into the housing 201. The nozzle connecting tube 211 functions as a delivery tube having a delivery nozzle 212.

[0093] Figure 3 shows a diagram of a LIB protection system disclosed herein used in a method for extinguishing flames and stopping thermal runaway in a lithium-ion battery-powered device such as those disclosed herein, wherein the thermal runaway cessation container is located inside the housing 301 rather than outside the housing. The housing 301 is a hazardous area that may experience a LIB fire originating from a LIB 302 located inside a lithium-ion battery (LIB) device 303. The LIB fire protection system includes a thermal runaway cessation agent supply source 304 comprising a thermal runaway cessation agent container 305 and a two-way control valve 306 connected to the thermal runaway cessation agent container 305 and a temperature-sensing tube 307, the end of which is sealed via a tube end seal 308. The temperature-sensing tube 307 is pressurized to a desired pressure with an inert gas or thermal runaway cessation agent. If a fire occurs in the LIB-type device 303, the portion of the temperature-sensing tube 307 that detects the maximum heat (threshold temperature) ruptures, forming an opening and releasing inert gas or thermal runaway arrestor from inside the temperature-sensing tube 307 into the housing 301. Simultaneously, this causes a pressure drop inside the temperature-sensing tube 307, which activates the two-way control valve 306, releasing the thermal runaway arrestor from the thermal runaway arrestor storage container 305 through the two-way control valve 306 into the temperature-sensing tube 307. The thermal stimulation of the temperature-sensing tube causes the arrestor to exit through the opening formed and be delivered into the housing 301. The release of the thermal runaway arrestor into the housing 301 extinguishes the flame and stops the thermal runaway in the LIB-type device 303, preventing re-ignition after the initial extinguishing of the flame.

[0094] Figure 3 is similar to Figures 1a and 1b. In the LIB fire protection system shown in Figure 3, the temperature sensing tube 307 functions as a temperature sensor (which can also be considered a fire detection device), an actuator or operating device for a control valve (which can also be considered a system activation device), and a delivery tube for delivering a thermal runaway arrestant into the housing.

[0095] Figure 4 shows a diagram of a LIB protection system disclosed herein used in a method for extinguishing flames and stopping thermal runaway in a device powered by a lithium-ion battery, as disclosed herein, wherein the thermal runaway stop container is located inside the housing 401 rather than outside the housing.

[0096] The enclosure 401 is a hazardous area that may experience a LIB fire originating from a LIB 402 located inside a lithium-ion battery (LIB) device 403. The LIB fire protection system includes a thermal runaway arrestor supply source 404 comprising a thermal runaway arrestor container 405 and a three-way control valve 406 connected to the thermal runaway arrestor container 405 and a temperature-sensing tube 407, the end of which is sealed via a tube end seal 408. The temperature-sensing tube 407 is pressurized to a desired pressure with an inert gas or thermal runaway arrestor. A nozzle connecting tube 411 is connected to the three-way control valve 406 and terminates at a delivery nozzle 412. In the event of a fire occurring in the LIB-type device 403, the part of the temperature-sensing tube 407 that detects the maximum heat (threshold temperature) ruptures, releasing the inert gas or thermal runaway arrestant inside the temperature-sensing tube 407 into the housing 401. Simultaneously, this causes a pressure drop inside the temperature-sensing tube 407, which activates the three-way control valve 406, diverting the flow from the temperature-sensing tube 407 to the nozzle connection pipe 411. The thermal runaway arrestant is then delivered from the thermal runaway arrestant storage container 405 through the three-way control valve 406 into the nozzle connection pipe 411, and then delivered to the outside through the delivery nozzle 412. The release of the thermal runaway arrestant into the housing 401 extinguishes the flame and stops the thermal runaway in the LIB-type device 403, preventing re-ignition after the initial extinguishing of the flame.

[0097] Figure 4 is similar to Figure 2. In the LIB fire protection system shown in Figure 4, the temperature sensing tube 407 functions as a temperature sensor (which can also be considered a fire detection device) and as an actuator or operating device for the control valve 406 (which can also be considered a system activation device), but it does not function as a delivery tube for delivering the thermal runaway arrestant into the housing 401. The nozzle connecting tube 411 functions as a delivery tube having a delivery nozzle 412.

[0098] Figure 5 is a schematic diagram of a typical lithium-ion battery (LIB). The LIB consists of an outer casing 520, within which the anode 521 is located in the anode chamber 522 of the LIB and the cathode 523 is located in the cathode chamber 524 of the LIB. The anode chamber 522 and the cathode chamber 524 are separated by a semipermeable membrane separator 525. The anode 521 is connected to a load 526 via an anode-load connector 527, and the cathode 523 is connected to the load 526 via a cathode-load connector 528. The anode 521 is protected by a solid electrolyte interface (SEI) layer 529. Both the anode chamber 522 and the cathode chamber 524 are filled with a liquid electrolyte (not shown). [Examples]

[0099] material 6700mAh lithium-ion power packs and aluminum-cased 3.2V DC LiFePO4 lithium-ion polymer batteries are commercially available from multiple suppliers including Duracell, Ravpower, and Tenergy. Chemours FM-200 (trademark) fire extinguishing agent (HFC-227ea) is available from The Chemours Company FC, LLC (Wilmington, Delaware). Rotarex direct low-pressure valves, Rotarex pressure switches, Rotarex FireDETEC temperature sensors, and termination adapters are all available from Rotarex SA in Luxembourg. The Harbin Coslight Model GYFP4875T data logger is available from Harbin Coslight Storage Battery Co., Ltd. in Heilongjiang Province, China.

[0100] Example 1 (Comparative Example). Free-burn test: Initiation of thermal runaway of the power pack due to mechanical failure. A 6700mAh lithium-ion power pack in a plastic case was subjected to thermal runaway due to mechanical damage. A weighted plunger with a drilling tip was used to observe a 1.15m closed-circuit television (CCTV) with an observation window. 3The battery was dropped through a guide pipe onto a power pack placed inside a steel test enclosure. When the battery was punctured, flames and thermal runaway occurred, which lasted for approximately 15 minutes.

[0101] Example 2 (Comparative Example). Free-burn test: Initiation of thermal runaway in a 3.2V DC LiFEPO4 battery due to mechanical failure. The procedure of Example 1 was repeated to induce thermal runaway in a 3.2V DC LiFePO4 lithium-ion polymer battery in an aluminum case. When the battery was punctured, flames and thermal runaway occurred, which lasted for approximately 15 minutes.

[0102] Example 3. Suppression of fire and thermal runaway in lithium-ion batteries: mechanical damage The procedure of Example 2 was repeated with the addition of a protective system installed inside the test enclosure. The protective system consisted of (1) a fire extinguishing agent storage container containing 2 kg of Chemors FM-200® fire extinguishing agent (for delivery of FM-200 at a concentration of 19.3%), (2) a Rotarex direct low-pressure valve positioned on the storage cylinder, (3) a Rotarex pressure switch positioned on the low-pressure valve, (4) a Rotarex FireDETEC temperature sensor tube of a certain length pressurized to 15 bar with nitrogen gas and positioned approximately 6 inches above the lithium-ion battery, and (5) a Rotarex termination line adapter fixed to the end of the temperature sensor tube. When the battery was punctured with a weighted plunger device, thermal runaway occurred, as demonstrated by flames. 22 seconds after the onset of thermal runaway, the system automatically started and released the FM-200® agent, and all flames were extinguished within 2 seconds. The release time was approximately 2 minutes. No re-ignition occurred after a 15-minute holding period, and no re-ignition occurred even when the test enclosure was opened and its contents were exposed to air.

[0103] Example 4. Suppression of fire and thermal runaway in lithium-ion batteries: Overcharge / overheated batteries Suppression tests were conducted against lithium-ion battery fire occurring in a Harbin Coslight model GYFP4875T data logger, which is powered by a battery pack consisting of 12 series-connected 3.2V DC LiFePO4 lithium-ion polymer batteries in aluminum cases. The data logger was placed in a 1m enclosure equipped with an observation window and protective system. 3 The system was housed in a 2-bay outdoor cabinet (ODC). The protection system consisted of (1) a fire extinguishing agent storage container containing 2 kg of Chemors FM-200® fire extinguishing agent (for delivery of FM-200 at 21.6% v / v), (2) a Rotarex direct low-pressure valve located on the storage cylinder, (3) a Rotarex pressure switch located on the low-pressure valve, (4) a Rotarex FireDETEC thermal sensor tube of a certain length pressurized to 15 bar with nitrogen gas and located approximately 6 inches above the lithium-ion battery, and (5) a Rotarex termination line adapter fixed to the end of the thermal sensor tube. Eleven batteries were charged to 100% charge, and one battery was overcharged by applying 3.4–3.6 volts (100–110 A). After 11 minutes of overcharging, a heater located on the overcharged cell was turned on to provide additional heating until thermal runaway, demonstrated by combustion, began. After 2 minutes, the system automatically started and released FM-200® agent (release time 2 minutes), and all flames were extinguished within 20 seconds. No re-ignition occurred after a 15-minute holding period, and no re-ignition occurred even when the test enclosure was opened and its contents were exposed to air.

Claims

1. A method for extinguishing a flame and stopping thermal runaway in a device powered by a lithium-ion battery, comprising: (a) providing a housing; (b) providing a device disposed within the housing, wherein the device comprises a lithium-ion battery and is powered by the lithium-ion battery; (c) providing a source of a thermal runaway deterrent, wherein the source includes a container and a two-way control valve, the container containing the thermal runaway deterrent, the two-way control valve being attached to an opening in the container, and the thermal runaway deterrent containing HFC-227ea; and (d) providing a temperature-sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, wherein the tube has two ends, (i) one end communicating with the control valve and the other end covered; and (ii) the tube being in the housing (iii) The tube is located inside the body and functions as a temperature sensor for detecting a threshold temperature, and the steps include (iii) the tube is positioned in close proximity to the lithium-ion battery, and (e) providing a thermal stimulus that generates a flame and initiates thermal runaway, wherein when the temperature-sensing tube ruptures, an opening ("thermal stimulus forming opening") is formed in the temperature-sensing tube, and the inert gas or thermal runaway arrestant inside the temperature-sensing tube is released into the housing through the thermal stimulus forming opening of the temperature-sensing tube, resulting in a decrease in the pressure inside the temperature-sensing tube, which activates the control valve to deliver the thermal runaway arrestant from the container through the control valve to the temperature-sensing tube, and delivers it out of the thermal stimulus forming opening of the temperature-sensing tube into the housing, wherein the delivery of the thermal runaway arrestant is characterized by the release time, the concentration of the thermal runaway arrestant, and the retention time, thereby extinguishing the flame, stopping the thermal runaway, and preventing re-ignition after the flame has been extinguished. A method wherein the thermal runaway arrestant comprises an amount of HFC-227ea sufficient to provide a concentration of HFC-227ea of ​​17% v / v or more when delivered to the housing.

2. The method according to claim 1, wherein in step (d), the temperature sensing tube contains an inert gas.

3. The method according to claim 2, wherein the inert gas is selected from nitrogen, argon, helium, carbon dioxide, and mixtures thereof.

4. The method according to claim 3, wherein the inert gas further comprises the thermal runaway arresting agent.

5. A method for extinguishing a flame and stopping thermal runaway in a device powered by a lithium-ion battery, comprising: (a) providing a housing; (b) providing a device disposed within the housing, wherein the device comprises a lithium-ion battery and is powered by the lithium-ion battery; (c) providing a source of a thermal runaway deterrent, wherein the source includes a container and a three-way control valve, the container containing the thermal runaway deterrent, the three-way control valve being attached to an opening in the container, and the thermal runaway deterrent containing HFC-227ea; and (d) providing a temperature-sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, wherein the tube has two ends, (i) one end communicating with the three-way control valve and the other end covered; (ii) the tube being located within the housing and functioning as a temperature sensor for detecting a threshold temperature; and (iii) (e) providing a nozzle connecting tube which communicates with the three-way control valve at one end and terminates at a nozzle adjacent to the lithium-ion battery at the other end; and (f) providing a thermal stimulus which generates a flame and initiates thermal runaway, wherein when the temperature sensing tube ruptures, an opening ("thermal stimulus forming opening") is formed in the temperature sensing tube, and the inert gas or thermal runaway arrestant inside the temperature sensing tube passes through the thermal stimulus forming opening of the temperature sensing tube. The process includes the step of releasing the thermal runaway arrestor into the housing, which in turn reduces the pressure inside the temperature sensing tube, activating the three-way control valve to deliver the thermal runaway arrestor from the container through the three-way control valve to the nozzle connecting tube, thereby releasing the thermal runaway arrestor from the nozzle into the housing, wherein the delivery of the thermal runaway arrestor is characterized by the release time, the concentration of the thermal runaway arrestor, and the holding time, thereby extinguishing the flame, stopping the thermal runaway, and preventing re-ignition after the flame has been extinguished. A method wherein the thermal runaway arrestant comprises an amount of HFC-227ea sufficient to provide a concentration of HFC-227ea of ​​17% v / v or more when delivered to the housing.

6. The method according to claim 5, wherein in step (d), the temperature-sensing tube contains an inert gas.

7. The method according to claim 6, wherein the inert gas is selected from nitrogen, argon, helium, carbon dioxide, and mixtures thereof.

8. The lithium-ion battery comprises an anode chamber containing an anode, a cathode chamber containing a cathode, and a semipermeable membrane separating the anode chamber from the cathode chamber, wherein the anode is made of graphite protected by a solid electrolyte interface layer, and the cathode is made of LiCoO 2 LiFePO 4 LiMn 2 O 4 Or LiNiMnCoO 2 The method according to any one of claims 1 to 7, comprising a lithium metal oxide selected from.

9. A fire prevention system comprising: (a) a housing; (b) a device disposed within the housing, comprising a lithium-ion battery and powered by the lithium-ion battery; (c) a thermal runaway deterrent source comprising a container and a two-way control valve, wherein the container contains the thermal runaway deterrent, the two-way control valve is attached to the opening of the container, and the thermal runaway deterrent contains HFC-227ea; and (d) a temperature sensing tube containing an inert gas or thermal runaway deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device, wherein the tube has two ends, (i) one end communicating with the two-way control valve and the other end covered, (ii) the tube located within the housing and functioning as a temperature sensor for detecting a threshold temperature, and (iii) the tube positioned close to the lithium-ion battery and capable of rupturing when the tube senses the threshold temperature. A fire protection system wherein the thermal runaway arrestant contains an amount of HFC-227ea sufficient to provide a concentration of HFC-227ea of ​​17% v / v or higher when delivered to the housing.

10. The fire protection system according to claim 9, wherein the temperature-sensing tube of component (c) contains an inert gas.

11. The fire prevention system according to claim 9, wherein the temperature-sensing tube of component (c) contains a thermal runaway arresting agent.

12. A fire prevention system comprising: (a) a housing; (b) a device disposed within the housing, comprising a lithium-ion battery and powered by the lithium-ion battery; (c) a thermal runaway deterrent supply source comprising a container and a three-way control valve, wherein the container contains the thermal runaway deterrent, the three-way control valve is attached to the opening of the container, and the thermal runaway deterrent contains HFC-227ea; and (d) an inert gas or thermal deterrent at a predetermined pressure and temperature suitable for the normal operating conditions of the device. A temperature-sensing tube for containing a deterrent, having two ends, (i) one end communicating with a three-way control valve and the other end covered, (ii) the temperature-sensing tube located inside the housing and functioning as a temperature sensor for detecting a threshold temperature, (iii) the temperature-sensing tube positioned close to the lithium-ion battery and capable of rupturing when the temperature-sensing tube detects the threshold temperature, and (e) a nozzle connecting tube, one end communicating with the three-way control valve and the other end terminating at a nozzle close to the lithium-ion battery, A fire protection system wherein the thermal runaway arrestant contains an amount of HFC-227ea sufficient to provide a concentration of HFC-227ea of ​​17% v / v or higher when delivered to the housing.

13. The fire protection system according to claim 12, wherein the temperature-sensing tube of component (c) contains an inert gas.

14. The fire prevention system according to claim 12, wherein the temperature-sensing tube of component (c) contains a thermal runaway arresting agent.

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