Protective equipment

Abstract

This system enables the rapid and efficient removal of smoke generated by fires caused by batteries such as lithium-ion batteries, thereby protecting the area to be protected. [Solution] The protective equipment protects a parking facility 10 where a battery-loaded vehicle 34, which is loaded with a battery unit containing a lithium-ion battery, is parked. It comprises an abnormality detection unit having a carbon dioxide sensor 28, a carbon monoxide sensor 30, and a hydrogen sensor 32 that detects fires caused by thermal runaway of lithium-ion batteries; a charged spraying head 26 capable of spraying charged liquid particles; a high-voltage power supply device that supplies a predetermined high voltage to the charged spraying head 26; and a system control panel that controls the spraying operation to spray charged liquid particles from the charged spraying head 26 when the abnormality detection unit detects an abnormality. The system control panel controls the spraying operation to spray charged liquid particles from the charged spraying head 26 that have the opposite polarity to the charge polarity of the smoke generated by a fire caused by thermal runaway of lithium-ion batteries.

Description

Technical Field

[0001] The present invention relates to a protective facility for protecting a target area where a battery unit having a predetermined battery is arranged from abnormalities such as fires.

Background Art

[0002] Conventionally, as protective facilities for parking lots, foam fire extinguishing facilities, carbon dioxide fire extinguishing facilities, fire extinguishing facilities using water spray heads, etc. have been installed in parking facilities (Patent Documents 1, 2).

[0003] In recent years, with the spread of electric vehicles (mobile bodies) equipped with lithium-ion batteries, the number of fires in parking facilities (including underground parking facilities) has also been on the increase. Fires occurring in electric vehicles are caused by thermal runaway of lithium-ion batteries in which the temperature of the lithium-ion battery rapidly rises to about 1000 to 1200 °C, and the damage tends to be enormous and extensive. Therefore, protective facilities are required to cope with fires caused by thermal runaway of lithium-ion batteries. Further, not only in parking facilities, but also in various facilities such as storage facilities for storing lithium-ion batteries and energy storage facilities for storing electric power by lithium-ion batteries, similar countermeasures are required.

[0004] For this reason, in order to cope with fires caused by thermal runaway of lithium-ion batteries, a system for extinguishing fires by spraying a thermal runaway inhibitor containing a non-combustible haloolefin has been proposed (Patent Document 3).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

[0006] Incidentally, the gases generated when a lithium-ion battery experiences thermal runaway for any reason mainly consist of hydrogen, carbon monoxide, methane, carbon dioxide, and hydrocarbon-based volatile organic compounds (VOCs). VOCs are organic solvents used in the electrolyte of lithium-ion batteries or their thermal decomposition products, and include ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl carbonate (EC), all of which are toxic to humans and the environment.

[0007] Furthermore, the inventors of this invention have confirmed that smoke generated by thermal runaway of lithium-ion batteries, and containing these gases, hardly settles naturally compared to the smoke concentrations of cellulose-based and hydrocarbon-based smoke.

[0008] Therefore, smoke generated by a fire caused by thermal runaway of lithium-ion batteries will remain in the atmosphere for a long time after spreading in the parking lot without naturally settling. If there are people in the parking lot, the smoke will obstruct their visibility and severely restrict their evacuation, and the highly toxic VOCs contained in the smoke could cause life-threatening injuries.

[0009] However, conventional protective equipment installed in parking lots cannot quickly and adequately remove smoke generated by fires caused by thermal runaway of lithium-ion batteries.

[0010] Furthermore, fire extinguishing liquids sprayed in environments where highly toxic gases are present may contain components of those gases, and if these liquids are disposed of without proper treatment, they could have adverse effects on people and the environment. Moreover, it is essential to be able to reliably respond to fires caused by batteries, not just lithium-ion batteries.

[0011] The present invention aims to provide protective equipment that can quickly and efficiently remove smoke generated by fires caused by batteries such as lithium-ion batteries, thereby protecting the area to be protected. [Means for solving the problem]

[0012] (protective equipment) A protective device for protecting a protected area in which a battery unit having a predetermined battery is located, An abnormality detection unit that detects abnormalities, including fires, caused by battery components located in the protected area, A charged spraying head capable of spraying charged liquid particles, which are liquid particles of fire extinguishing liquid charged with electricity, onto a protected area, A voltage supply unit that supplies a predetermined high voltage to the charged spraying head when the charged spraying head sprays charged liquid particles, When the abnormality detection unit detects an abnormality, the control unit controls the spraying operation that sprays charged liquid particles from the charged spraying head, Equipped with, The control unit controls the spraying operation so that charged liquid particles with the opposite polarity to the charge polarity of a predetermined smoke generated by a fire caused by the battery unit are sprayed from the charged spraying head.

[0013] (Dispersion operation with switched charge polarity) The control unit controls the spraying operation so that the charge polarity of the charged liquid particles sprayed from the charged spraying head is switched at predetermined timings, and positively charged liquid particles and negatively charged liquid particles are sprayed alternately from the charged spraying head.

[0014] (Protective equipment to deal with fires caused by thermal runaway in lithium-ion batteries) The battery in the battery section is a lithium-ion battery. The abnormality detection unit detects a fire caused by thermal runaway of a lithium-ion battery as a fire originating from the battery section. The control unit controls the spraying operation so that positively charged liquid particles, which have the opposite polarity to the negatively charged smoke generated by a fire caused by thermal runaway of a lithium-ion battery, are sprayed from the charged spraying head.

[0015] (Method for Detecting Fire Caused by Thermal Runaway of Lithium-Ion Battery 1) The abnormality detection unit includes a hydrogen sensor, a carbon dioxide sensor, and a carbon monoxide sensor, When all the detection results of the hydrogen sensor, the carbon dioxide sensor, and the carbon monoxide sensor satisfy a predetermined detection condition, the control unit determines that the abnormality detection unit has detected a fire caused by the thermal runaway of the lithium-ion battery.

[0016] (Method for Detecting Fire Caused by Thermal Runaway of Lithium-Ion Battery 2) The abnormality detection unit includes an oxygen concentration detection unit that detects the oxygen concentration, Based on the detected oxygen concentration, the oxygen concentration detection unit detects a fire caused by the thermal runaway of the lithium-ion battery.

[0017] (Detection of Abnormality Based on Charged Amount of Smoke) The abnormality detection unit includes a smoke detection device capable of detecting the charged amount of smoke generated by an abnormality, The smoke detection device determines whether the detected charged amount is the charged amount of smoke generated by an abnormality, and when it determines that it is the charged amount of smoke generated by an abnormality, it detects the abnormality.

[0018] (Control of Spraying Operation Based on Charged Polarity of Detected Smoke) The smoke detection device is further capable of detecting the charged polarity of smoke generated by an abnormality, and when it detects an abnormality, it transmits information regarding the charged polarity of the detected smoke to the control unit, The control unit controls the spraying operation so that the charged polarity of the charged liquid particles is the opposite polarity of the charged polarity of the smoke detected by the smoke detection device.

[0019] (Detection of Abnormality Based on Charged Polarity of Smoke) The abnormality detection unit includes a smoke detection device capable of detecting the charged polarity of smoke generated by an abnormality, The smoke detection device determines whether the detected charged polarity is the charged polarity of smoke generated by an abnormality, and when it determines that it is the charged polarity of smoke generated by an abnormality, it detects the abnormality.

[0020] (Control of spraying behavior based on the detected charge polarity of smoke) When the smoke detection device detects an abnormality, it transmits information regarding the charge polarity of the detected smoke to the control unit. The control unit controls the dispersal operation so that the charge polarity of the charged liquid particles is the opposite polarity of the charge polarity of the smoke detected by the smoke detection device.

[0021] (Drainage structure) It is equipped with a drainage structure that collects the fire extinguishing liquid sprayed on the protected area into a wastewater recovery tank.

[0022] (Protective equipment for a protected area divided into protected zones) The area to be protected is divided into multiple protected sections corresponding to the location where the battery is placed. For each protected area, Anomaly detection unit, Electrostatic dispersal head and A fire extinguishing liquid spraying head for spraying fire extinguishing liquid onto the battery section of the protected area, A water curtain forming head sprays fire extinguishing liquid from the ceiling side of the protected area to form a water curtain surrounding the protected area to which it belongs, A system was established, When any of the abnormality detection units detect an abnormality, the control unit controls a spraying operation that, in addition to spraying charged liquid particles from the charged spraying head, sprays fire extinguishing liquid from the fire extinguishing liquid spraying head and sprays fire extinguishing liquid from the water curtain forming head to form a water curtain, for a predetermined protected area including the protected area where the abnormality was detected.

[0023] (Manual operation section of the water film forming head) A manual control unit is provided at a predetermined location corresponding to the area to be protected, which controls the start and stop of water discharge from the water curtain forming heads, each corresponding to the protected area.

[0024] (Protective equipment for parking facilities) The area to be protected is a parking facility for a mobile vehicle equipped with a battery unit, and is divided into multiple protected sections corresponding to the parking locations of the mobile vehicle.

[0025] (Protective equipment for battery storage facilities) The area to be protected is a battery storage facility where the battery unit is stored, and it is divided into multiple protected sections corresponding to the storage location of the battery unit.

[0026] (Protective equipment for energy storage facilities) The area to be protected is an energy storage facility that stores electricity using battery units, and is divided into multiple protected sections corresponding to the location of the battery units. [Effects of the Invention]

[0027] (Effectiveness of protective equipment) The present invention provides a protective device for protecting a protected area in which a battery unit having a predetermined battery is located, comprising: an abnormality detection unit that detects abnormalities, including fires, caused by the battery unit located in the protected area; a charged spraying head capable of spraying charged liquid particles, which are liquid particles of fire extinguishing liquid that have been charged; a voltage supply unit that supplies a predetermined high voltage to the charged spraying head when the charged spraying head sprays the charged liquid particles; and a control unit that controls the spraying operation to spray charged liquid particles from the charged spraying head when the abnormality detection unit detects an abnormality. The control unit controls the spraying operation to spray charged liquid particles from the charged spraying head that have the opposite polarity to the charge polarity of a predetermined smoke generated by a fire caused by the battery unit. As a result, the charged liquid particles, which are charged with the opposite polarity to the charge polarity of the generated smoke, are efficiently attracted to the smoke particles by electrostatic force, causing the smoke to settle quickly and efficiently, thereby ensuring the visibility necessary for evacuation, protecting people from toxic substances, and reliably reducing casualties.

[0028] (Effect of switching the charging polarity during spraying) The control unit controls the spraying operation so that the charge polarity of the charged liquid particles sprayed from the charged spraying head is switched at predetermined timings, and positively charged liquid particles and negatively charged liquid particles are sprayed alternately from the charged spraying head. This makes it possible to spray charged liquid particles with the appropriate polarity even when the charge polarity of the smoke changes over time or when multiple types of smoke with different polarities are generated, allowing the smoke to settle quickly and efficiently, ensuring the visibility necessary for evacuation, protecting people from toxic substances, and reliably reducing casualties.

[0029] (Effectiveness of protective equipment against fires caused by thermal runaway of lithium-ion batteries) Furthermore, if the battery in the battery unit is a lithium-ion battery, experiments by the inventors have confirmed that the smoke generated by a fire caused by thermal runaway of the lithium-ion battery is negatively charged. Therefore, by controlling the charged liquid particles sprayed from the charged spraying head to be positively charged, it is possible to quickly and efficiently settle the smoke generated by a fire caused by thermal runaway of the lithium-ion battery, thereby reliably reducing casualties.

[0030] (Effectiveness of Fire Detection Method 1 Caused by Thermal Runaway of Lithium-ion Batteries) Furthermore, since thermal runaway in lithium-ion batteries generates gases containing hydrogen, carbon dioxide, and carbon monoxide, the abnormality detection unit is equipped with a hydrogen sensor, a carbon dioxide sensor, and a carbon monoxide sensor. This allows for the detection of a fire caused by thermal runaway in a lithium-ion battery when all three sensors meet the predetermined detection conditions.

[0031] (Effectiveness of Fire Detection Method 2, which detects fires caused by thermal runaway in lithium-ion batteries) Furthermore, the inventors of this invention have experimentally confirmed that oxygen, as a combustion product resulting from the temperature rise of a lithium-ion battery that leads to thermal runaway, can be detected from the rising oxygen concentration. Therefore, the abnormality detection unit is equipped with an oxygen concentration detection unit that detects the oxygen concentration, and based on the oxygen concentration detected by the oxygen concentration detection unit, it is possible to detect a fire caused by thermal runaway of a lithium-ion battery.

[0032] (The effect of detecting anomalies based on the amount of electric charge in smoke) The anomaly detection unit is equipped with a smoke detection device capable of detecting the amount of charge generated by smoke due to an anomaly. The smoke detection device determines whether the detected charge is the amount of charge generated by smoke due to an anomaly, and if it determines that it is the amount of charge generated by smoke due to an anomaly, it detects an anomaly. This enables the detection of anomalies based on the amount of charge of smoke, which differs from conventional smoke detectors. Furthermore, detecting the amount of charge of smoke does not require an optical structure like that found in conventional smoke detectors, making it possible to create an anomaly detection unit with excellent resistance to contamination.

[0033] (The effect of detecting anomalies based on the charge polarity of smoke) The abnormality detection unit is equipped with a smoke detection device capable of detecting the charge polarity of smoke generated by an abnormality. The smoke detection device determines whether the detected charge polarity is that of smoke generated by an abnormality, and if it determines that it is the charge polarity of smoke generated by an abnormality, it detects the abnormality. This enables the detection of abnormalities based on the charge polarity of smoke, which differs from conventional smoke detectors. Furthermore, detecting the charge polarity of smoke does not require an optical structure like that found in conventional smoke detectors, making it possible to create an abnormality detection unit with excellent resistance to contamination.

[0034] (Effect of controlling spraying behavior based on the detected charge polarity of smoke) The smoke detection device transmits information regarding the charge polarity of the detected smoke to the control unit, and the control unit controls the spraying operation so that the charge polarity of the charged liquid particles is the opposite of the charge polarity of the smoke detected by the smoke detection device. As a result, it becomes possible to spray charged liquid particles with the opposite charge polarity of the smoke from the charged spraying head, thereby enhancing the smoke suppression effect.

[0035] (Effects of drainage structure) Furthermore, the system is equipped with a drainage structure that collects the fire extinguishing liquid sprayed on the protected area into a wastewater recovery tank. This prevents the used fire extinguishing liquid from being simply discarded, thus ensuring safety for people and the environment.

[0036] (Effectiveness of protective equipment in a protected area divided into protected zones) Furthermore, the protected area is divided into multiple protected compartments corresponding to the location where the battery unit is placed. Each protected compartment is provided with an abnormality detection unit, a charged spraying head, a fire extinguishing liquid spraying head that sprays fire extinguishing liquid onto the battery unit from the floor side of the protected compartment, and a water curtain forming head that sprays fire extinguishing liquid from the ceiling side of the protected compartment to form a water curtain surrounding the protected compartment to which it belongs. When any of the abnormality detection units detect an abnormality, the control unit controls a spraying operation that, in addition to spraying charged liquid particles from the charged spraying head, sprays fire extinguishing liquid from the fire extinguishing liquid spraying head and sprays fire extinguishing liquid from the water curtain forming head to form a water curtain for a predetermined protected compartment including the protected compartment where the abnormality was detected. As a result, a sufficient amount of fire extinguishing liquid is sprayed onto the battery unit by the fire extinguishing liquid spraying head to cool and extinguish the fire, and the water curtain formed by the water curtain forming head suppresses and prevents the propagation of radiant heat from the fire to other protected compartments, thereby preventing the spread of the fire.

[0037] Furthermore, since the spraying of fire extinguishing liquid can be controlled for each protected area, it is possible to spray fire extinguishing liquid only on specific protected areas, thereby suppressing and preventing unnecessary water damage.

[0038] (Effect of the manual control section of the water film forming head) A manual control unit is provided at a predetermined location corresponding to the area to be protected, which controls the start and stop of water discharge from the water curtain forming heads, corresponding to each protected section. Although the control unit basically sprays fire extinguishing liquid from the water curtain forming heads to form a water curtain, even if the water curtain is not formed properly due to a malfunction of the control unit, it is possible to form the water curtain by operating the manual control unit. [Brief explanation of the drawing]

[0039] [Figure 1] This is an explanatory diagram showing a front view of the first embodiment of the protective equipment. [Figure 2] This is an explanatory diagram showing a plan view of the first embodiment of the protective equipment. [Figure 3] This is an explanatory diagram showing the structure of the electrostatic dispersal head. [Figure 4] This is an explanatory diagram showing the configuration of the voltage supply unit together with the electrostatic dispersal head. [Figure 5] This is an explanatory diagram showing the time-dependent change in smoke concentration of smoke generated during a fire experiment involving a lithium-ion battery. [Figure 6] This is an explanatory diagram showing the time change in the charge polarity of a flame generated in a fire experiment involving a lithium-ion battery. [Figure 7] This is an explanatory diagram showing the time change in the charge polarity of smoke generated in a fire experiment involving a lithium-ion battery. [Figure 8] This is an explanatory diagram showing the protective equipment in operation in a battery-equipped vehicle during a fire caused by thermal runaway of a lithium-ion battery, as viewed from the front. [Figure 9] This is an explanatory diagram showing the protective equipment in operation in a battery-equipped vehicle when a fire occurs due to thermal runaway of a lithium-ion battery, as shown in a plan view. [Figure 10] This is an explanatory diagram showing a front view of a second embodiment of the protective equipment. [Figure 11] This is an explanatory diagram showing a plan view of the second embodiment of the protective equipment. [Figure 12] This is an explanatory diagram showing a front view of the third embodiment of the protective equipment. [Figure 13]This is an explanatory diagram showing the configuration of a smoke detection device. [Figure 14] This is an explanatory diagram showing the main unit of the smoke detection device. [Figure 15] This is an explanatory diagram showing the internal structure of a smoke detection device. [Figure 16] This is an explanatory diagram showing the rotating electrode of the main body of the device. [Figure 17] This is an explanatory diagram showing the cage electrodes of the device body removed and in an assembled / disassembled state. [Figure 18] This is an explanatory diagram showing the details of the first and second gauge electrodes that make up the cage electrode. [Figure 19] Figure 15 is an explanatory diagram showing the area around the circuit housing along with an oscilloscope. [Figure 20] This is an explanatory diagram showing the rotational positions of the rotating electrode relative to the flue pipe and cage electrode, divided into rotational positions of 0°, 45°, 90°, and 135°. [Figure 21] This is an explanatory diagram showing the charge distribution on the flue pipe and cage electrode when the rotating electrode is at a rotational position of 0°. [Figure 22] This is an explanatory diagram showing the charge distribution on the flue pipe and cage electrode when the rotating electrode is rotated at a 45° position. [Figure 23] This is an explanatory diagram showing the charge distribution on the flue pipe and cage electrode when the rotating electrode is rotated at a 90° position. [Figure 24] This is an explanatory diagram showing the charge distribution on the flue pipe and cage electrode at a rotational position of 135° for the rotating electrode. [Figure 25] These are explanatory diagrams showing the charge detection voltage signal that changes sinusoidally in accordance with the rotational position of the rotating electrode in Figures 21 to 24. [Figure 26] This is an explanatory diagram showing a front view of the fourth embodiment of the protective equipment. [Figure 27] This is an explanatory diagram showing a plan view of the fourth embodiment of the protective equipment. [Figure 28] This is an explanatory diagram showing a front view of the fifth embodiment of the protective equipment. [Figure 29]This is an explanatory diagram showing the time-dependent change in oxygen concentration measured in a lithium-ion battery fire experiment. [Modes for carrying out the invention]

[0040] Embodiments of the protective equipment according to the present invention will be described below with reference to the drawings. However, the present invention is not limited to the embodiments described below.

[0041] [Basic Concepts of the Embodiment] First, the basic concept of the embodiment will be explained. The embodiment generally relates to a protective device that protects a protected area, where a battery unit having a predetermined battery is located, from abnormalities such as fire.

[0042] "Specified batteries" refer to various types of batteries that can cause fires, including, for example, rechargeable batteries such as lithium-ion batteries and solid-state batteries.

[0043] The term "battery unit" includes mobile devices such as electric vehicles equipped with lithium-ion batteries, devices with batteries, batteries, etc., and also includes those consisting of only one or more batteries. Furthermore, the number of batteries contained in the battery unit is arbitrary and can be one or any number of batteries.

[0044] "Protective equipment" is equipment that protects a protected area by extinguishing fires, especially those caused by batteries in the battery section, such as thermal runaway of batteries. However, because it is configured to spray charged liquid particles that have both high fire extinguishing and smoke-reducing effects, it also includes the meaning of equipment that protects a protected area by suppressing smoke generated by fires or other abnormalities, and it is a concept that also includes "protective systems."

[0045] The term "protected area" is a concept that includes places or spaces protected by protective equipment, i.e., places or spaces where fire extinguishing liquid is sprayed, sources of smoke, fire sources, or places or spaces where these exist. Furthermore, the term "protected area" is not limited to places or spaces separated from the outside by walls, etc., but also includes places or spaces that are partially open to the outside.

[0046] Furthermore, the "protected area" includes parking facilities for mobile vehicles equipped with battery units, battery storage facilities for storing battery units, and energy storage facilities for storing electricity using battery units. "Mobile vehicles" include vehicles equipped with high-voltage batteries, such as hybrid vehicles, plug-in hybrid vehicles, electric vehicles, and fuel cell vehicles. In addition, "placing a battery unit in the protected area" includes parking a mobile vehicle loaded with a battery unit if the protected area is a parking facility, placing a battery unit for storage if the protected area is a battery storage facility, and installing a battery unit if the protected area is an energy storage facility.

[0047] Furthermore, the "protective equipment" of the embodiment includes an "abnormality detection unit," a "charged spraying head," a "voltage supply unit," and a "control unit" to enable the rapid and efficient removal of smoke generated by a fire caused by the battery unit.

[0048] The "anomaly detection unit" is a means for detecting anomalies, including fires caused by batteries in a battery unit located in the protected area. It should be noted that the anomaly detection unit is not limited to fires caused by batteries in the battery unit; it can also be configured to detect other anomalies, such as fires occurring in the protected area that are not caused by batteries.

[0049] Furthermore, in the case of a lithium-ion battery, thermal runaway of a lithium-ion battery generates gas (white smoke) containing various combustion products such as hydrogen, carbon dioxide, and carbon monoxide. Therefore, the "abnormality detection unit" is equipped with, for example, a hydrogen sensor, a carbon dioxide sensor, and a carbon monoxide sensor. When all three sensors meet predetermined detection conditions, the unit detects a fire caused by thermal runaway of the lithium-ion battery (a fire originating from the battery itself). Although this explanation uses a lithium-ion battery as an example, the components of the gas generated will differ depending on the battery material. Therefore, the sensors equipped in the abnormality detection unit and the detection conditions for detecting a fire originating from the battery itself will be selected as appropriate.

[0050] Furthermore, "thermal runaway of lithium-ion batteries" is a phenomenon in which a lithium-ion battery enters an abnormal heat state where it can reach high temperatures of 1000-1200°C due to certain causes, and in the worst case, it can ignite or explode. If it reaches the point of ignition or explosion, it can develop into a fierce fire. The causes of thermal runaway of lithium-ion batteries can be mainly divided into physical causes and electrical causes.

[0051] A lithium-ion battery primarily consists of a positive electrode, a negative electrode, a separator separating the positive and negative electrodes, and an electrolyte solution filled into each of the positive and negative electrode sections. During charging and discharging, lithium ions move through the separator and into the electrolyte solution. Lithium ions from the positive electrode move to the negative electrode, creating a potential difference between the two electrodes for charging, and lithium ions from the negative electrode move to the positive electrode, creating a potential difference between the two electrodes for discharging.

[0052] The physical cause of thermal runaway in lithium-ion batteries is physical damage or deformation of any part of the lithium-ion battery. For example, the separator may be damaged by impact or pressure. When the separator is damaged, a short circuit occurs between the positive and negative electrodes. When a short circuit occurs, current flows rapidly to the negative electrode, causing it to overheat. The heated negative electrode then heats the positive electrode, triggering an exothermic reaction in the positive electrode. This triggers various heat-generating chemical reactions, such as reactions between the negative and positive electrodes and the electrolyte, decomposition of the electrolyte itself, and combustion reactions caused by sparks during the short circuit and oxygen released due to the collapse of the positive electrode's crystal structure. Ultimately, this leads to thermal runaway.

[0053] Furthermore, the electrical cause of thermal runaway in lithium-ion batteries is overcharging or over-discharging. When overcharged, the potential of the positive electrode relative to the negative electrode increases, causing the electrolyte to oxidize and decompose, resulting in heat generation on the positive electrode side. This heat gradually causes the separator to shrink and deform, short-circuiting the positive and negative electrodes. This triggers various heat-generating chemical reactions, similar to those caused by physical factors, and accelerates the shrinkage and deformation of the separator, ultimately leading to thermal runaway.

[0054] Therefore, lithium-ion batteries are equipped with measures to prevent thermal runaway, such as programmed control to prevent overcharging and over-discharging, the use of flame retardants that do not ignite even when heated, and physical shutdown of reactions at high temperatures. However, it is difficult to completely prevent thermal runaway in lithium-ion batteries, and protective equipment is needed to protect against fires caused by thermal runaway in lithium-ion batteries.

[0055] Furthermore, if the battery is a lithium-ion battery, the "abnormality detection unit" may be equipped with an oxygen concentration detection unit that detects oxygen concentration instead of a hydrogen sensor, carbon dioxide sensor, and carbon monoxide sensor. The "oxygen concentration detection unit" detects a fire caused by thermal runaway of the lithium-ion battery based on the detected oxygen concentration.

[0056] The reason for using an oxygen concentration detection unit in the abnormality detection section is that the inventor of this application has confirmed through experiments that "oxygen" can be detected as a combustion product associated with the temperature rise of a lithium-ion battery leading to thermal runaway, based on the rising oxygen concentration. The "oxygen concentration detection unit" can detect a fire caused by thermal runaway of a lithium-ion battery by using the detected oxygen concentration value, its change, and its rate of change. It should be noted that there is no prerequisite for including an oxygen concentration detection unit in addition to a hydrogen sensor, carbon dioxide sensor, and carbon monoxide sensor. For example, if all of the hydrogen sensor, carbon dioxide sensor, and carbon monoxide sensor satisfy predetermined detection conditions, and the oxygen concentration detection unit detects a predetermined oxygen concentration, a fire caused by thermal runaway of a lithium-ion battery may be detected.

[0057] Furthermore, the "anomaly detection unit" may be equipped with a smoke detection device capable of detecting the amount of charge of smoke generated by an anomaly, the polarity of the charge of smoke, or both the amount of charge of smoke and the polarity of smoke. The "smoke detection device" determines whether the detected amount of charge or polarity is the amount of charge or polarity of smoke generated by an anomaly, and detects an anomaly if it is determined to be the amount of charge or polarity of smoke generated by an anomaly.

[0058] Furthermore, the "smoke detection device," when it can detect the charge polarity of smoke generated by an abnormality, transmits information regarding the detected charge polarity of the smoke to the control unit when an abnormality is detected, thereby enabling the dispersal of charged liquid particles with the opposite polarity to that of the smoke.

[0059] Furthermore, one type of "smoke detection device" capable of detecting the amount of electric charge and polarity of smoke is one equipped with a rotary chopper-type Faraday cage structure. Details of smoke detection devices equipped with a rotary chopper-type Faraday cage structure will be described later.

[0060] Furthermore, in the event of thermal runaway of a lithium-ion battery, a gas (white smoke) containing various combustion products such as hydrogen, carbon dioxide, and carbon monoxide is generated. A smoke detection device can detect the amount of charge and polarity of this white smoke, and an abnormality detection unit equipped with a smoke detection device can detect abnormalities that generate smoke, such as fires, caused by thermal runaway of a lithium-ion battery.

[0061] The "charged spraying head" sprays fire extinguishing liquid onto the area to be protected, and the "voltage supply unit" supplies the high voltage necessary to charge the liquid particles when the charged spraying head sprays the charged liquid particles to the open-type head, and the "charged spraying head" is able to spray charged liquid particles by receiving a predetermined high voltage from the voltage supply unit to charge the liquid particles of the fire extinguishing liquid.

[0062] Furthermore, the "charged spraying head" is capable of spraying charged liquid particles, but it can also spray uncharged liquid particles. By supplying a predetermined high voltage from the voltage supply unit, it is possible to selectively spray charged liquid particles and uncharged liquid particles.

[0063] Furthermore, the term "dispersion" is a concept that can include alternative terms such as release, spraying, eruption, and misting, depending on the meaning of the term.

[0064] Furthermore, the number of "anomaly detection units," "charged dispersal heads," and "voltage supply units" in the protective equipment is arbitrary and can be one or more depending on the size of the area to be protected.

[0065] The "control unit" controls the spraying operation, which involves spraying charged liquid particles from the charged spraying head when the abnormality detection unit detects an abnormality. By controlling the spraying operation to spray charged liquid particles from the charged spraying head that have the opposite polarity to the charge polarity of a predetermined smoke generated by a fire caused by the battery unit, the charged liquid particles are efficiently adsorbed to the smoke particles by electrostatic force, causing the smoke to settle quickly and efficiently. This ensures the visibility necessary for evacuation, protects people from toxic substances, and reliably reduces casualties.

[0066] In this case, if the battery in the battery unit is a lithium-ion battery, the inventor's experiments have confirmed that the smoke generated by a fire caused by thermal runaway of the lithium-ion battery is negatively charged. Therefore, if the battery in the battery unit is a lithium-ion battery, the control unit controls the spraying operation so that the charged liquid particles sprayed from the charged spraying head are positively charged.

[0067] Furthermore, in protective equipment, charged liquid particles charged with the opposite polarity to the smoke's charge polarity are sprayed from a charged spraying head, but how the charge polarity of the sprayed charged liquid particles is determined is arbitrary. For example, if the type of battery in the battery unit placed in the area to be protected is predetermined, the charge polarity of the smoke generated can be investigated in advance through experiments, etc., as with the lithium-ion battery mentioned above, and the charged liquid particles can be set to be charged with the opposite polarity to that smoke's charge polarity.

[0068] Furthermore, if the type of battery in the battery unit placed in the protected area is not determined and the charge polarity of the generated smoke cannot be determined in advance, the charge polarity of the smoke generated in the protected area can be detected by using a charge detector that detects the charge polarity of a particulate mixture including smoke particles, such as the one disclosed by the present inventor in Japanese Patent Application Publication No. 2023-033790 (Japanese Patent Application No. 2021-139693). The control unit can then be set to control the liquid particles to be charged with the opposite polarity to the detected charge polarity.

[0069] Furthermore, if the abnormality detection unit is equipped with the aforementioned smoke detection device, the abnormality detection unit can detect the charge polarity of the smoke. Therefore, without requiring any additional devices or equipment, the smoke detection device can detect the charge polarity of the smoke generated in the protected area, and the control unit can control the dispersal of charged liquid particles with the opposite polarity to the charge polarity of the smoke detected by the smoke detection device.

[0070] Furthermore, depending on the type of battery in the battery unit placed in the protected area, the charge polarity of the generated smoke may change over time, or positively charged and negatively charged smoke may be mixed together. Additionally, there may be multiple types of batteries in the battery unit placed in the protected area, resulting in the generation of smoke with different polarities depending on the battery type.

[0071] In such cases, it is not always appropriate to spray either positively or negatively charged liquid particles. Therefore, the "spraying operation in which charged liquid particles with the opposite polarity to the charged polarity of a predetermined smoke generated by a fire caused by the battery are sprayed from a charged spraying head" is not limited to spraying either positively or negatively charged liquid particles, but includes spraying operations in which charged liquid particles with different polarities are sprayed depending on the passage of time and the location where the charged liquid particles are sprayed.

[0072] For example, the "control unit" may control the spraying operation so that the charge polarity of the charged liquid particles sprayed from the charged spraying head is switched at predetermined timings, and positively charged liquid particles and negatively charged liquid particles are sprayed alternately from the charged spraying head.

[0073] Here, the "predetermined timing" for switching the charge polarity of the charged liquid particles is arbitrary, but includes, for example, setting a switching cycle and switching when one cycle has elapsed, or, as mentioned above, detecting the charge polarity of the smoke and switching when the detected charge polarity of the smoke changes. Furthermore, when periodically switching the charge polarity of the charged liquid particles, for example, the voltage supplied from the voltage supply unit to the charged spraying head may be an AC voltage or a pulsed voltage, and the voltage supplied from the voltage supply unit to the charged spraying head may change in an AC or pulsed manner over time.

[0074] Furthermore, because the extinguishing liquid used after spraying is hazardous and could have adverse effects on people and the environment if simply disposed of, the protective equipment is equipped with a "drainage structure" that collects the extinguishing liquid sprayed on the protected area into a wastewater recovery tank.

[0075] Furthermore, the "protected area" may be divided into multiple protected compartments corresponding to the location where the battery unit is placed. If the protected area is divided into multiple protected compartments, each protected compartment is provided with an "abnormality detection unit," a "charged spraying head," a "fire extinguishing liquid spraying head," and a "water curtain forming head." When any of the abnormality detection units detect an abnormality, the "control unit" controls a spraying operation that, in addition to spraying charged liquid particles from the charged spraying head, sprays fire extinguishing liquid from the fire extinguishing liquid spraying head and sprays fire extinguishing liquid from the water curtain forming head to form a water curtain, for a predetermined protected compartment including the protected compartment where the abnormality was detected, such as the protected compartment where the abnormality was detected or a protected compartment located within a predetermined range from the protected compartment where the abnormality was detected.

[0076] Here, "protected compartments" do not necessarily have to be completely physically separated from adjacent storage compartments; there may be open spaces between adjacent protective compartments, and even if adjacent protective compartments are separated by wall members or the like, the protective members may be in a mesh shape or similar, and the adjacent storage compartments do not necessarily have to be completely separated. In other words, "protected compartments" encompass both physically separated compartments and conceptually separated compartments.

[0077] The "fire extinguishing liquid spraying head" sprays fire extinguishing liquid onto the battery section from, for example, the floor or ceiling side of the protected area, while the "water curtain forming head" sprays fire extinguishing liquid from the ceiling side of the protected area to form a water curtain that surrounds the protected area to which it belongs.

[0078] Furthermore, the "water curtain" formed by the water curtain forming head does not need to completely enclose the protected area to which it belongs. For example, if a wall member or the like is placed between the protected area and the outside or between adjacent protected areas, and such wall member or the like can suppress or prevent the propagation of radiant heat from fire to the outside of the protected area or other protected areas, then a water curtain does not need to be formed at the location of the wall member or the like. However, this does not prevent the formation of a water curtain including the location of the wall member or the like.

[0079] Furthermore, the area partitioned by the formation of a "water curtain" is called a "fire-resistant compartment," and the "fire-resistant compartment" does not necessarily have to be the same area as the protective compartment. It may be a smaller area than the protective compartment, for example, as long as it includes the location where the battery section of the protective compartment is located.

[0080] Furthermore, the number of "anomaly detection units," "electrostatic spraying heads," "fire extinguishing liquid spraying heads," and "water curtain forming heads" installed in each protected area is arbitrary and can be one or more depending on the size of the protected area; the number does not need to be the same for each area.

[0081] Furthermore, a manual control unit is provided at a predetermined location corresponding to the area to be protected, for example, near the entrance / exit of the area to be protected or outside the area to be affected by disaster prevention, to operate the start and stop of water discharge from the water curtain forming heads provided for each protected section.

[0082] Furthermore, if the "protected area" is a parking facility, the protected area corresponds to the parking location of the mobile vehicle, and if the "protected area" is a battery storage facility, the protected area corresponds to the storage location of the battery unit.

[0083] Furthermore, when the area to be protected against disasters is divided into multiple protected sections, the "voltage supply unit" may be provided individually for each protected section, or a common voltage supply unit may be provided for the entire protective equipment or a predetermined number of protected sections as a group, and different power wiring may be drawn from the common voltage supply unit to the electrostatic spraying heads of each protected section.

[0084] Furthermore, if the protective equipment includes a "fire extinguishing liquid spraying head" and a "water curtain forming head," the fire extinguishing liquid sprayed from these heads will also be collected in the drainage recovery tank of the drainage structure.

[0085] The following describes specific embodiments. In the following embodiments, the first embodiment is defined as the case where the "protected area" is a "parking facility for a mobile vehicle loaded with a battery unit," the "battery in the battery unit" is a "lithium-ion battery," the "fire caused by the battery unit" is a "fire caused by thermal runaway of the lithium-ion battery," the "fire extinguishing liquid" is "fire extinguishing water," and the "abnormality detection unit" is "equipped with a carbon dioxide sensor, a carbon monoxide sensor, and a hydrogen sensor." The second embodiment is defined as the first embodiment with a drainage structure added. The third embodiment is defined as the first embodiment with the abnormality detection unit changed to "equipped with a smoke detection device." The fourth embodiment is defined as the third embodiment where the "protected area" is an "energy storage facility." The fifth embodiment is defined as the case where the "abnormality detection unit" is "equipped with an oxygen concentration detection unit." These five embodiments will be described separately.

[0086] [Specific details of the embodiment] The specific details of the implementation using protective equipment will be explained separately as follows. a. First embodiment of protective equipment a1. Overall configuration of protective equipment a2. System control panel and pressurized water supply equipment a3. Structure of the electrostatic dispersal head a4. Configuration of the high-voltage power supply unit b. Fire characteristics of lithium-ion batteries b1. Smoke concentration and sedimentation velocity b2: Charge polarity of flame and smoke c. Operation of protective equipment d. Second embodiment of protective equipment e. Third embodiment of protective equipment e1. Configuration of protective equipment e2. Configuration of the smoke detection device e3. Detailed structure of the smoke detection device e4. Charge detection unit e5. Rotational position of the rotating electrode and charge generation of the cage electrode e6. Abnormality determination section f. Fourth embodiment of protective equipment f1. Configuration of protective equipment f2. Operation of protective equipment g. Fifth embodiment of protective equipment g1. Configuration of protective equipment g2. Changes in oxygen concentration during thermal runaway of lithium-ion batteries h. Modified Examples of the Invention

[0087] [a. First embodiment of protective equipment] First, a first embodiment of the protective equipment will be described.

[0088] (a1. Overall configuration of protective equipment) The overall configuration of the protective equipment will be explained. In this explanation, refer to Figure 1, which shows a front view (viewed from the front) of the first embodiment of the protective equipment, and Figure 2, which shows a top view (viewed from above) of the first embodiment of the protective equipment.

[0089] The parking facility 10 has multiple parking spaces 12(12-1) to 12(12-6), and each parking space 12(12-1) to 12(12-6) is capable of accommodating one mobile vehicle entering and exiting through the vehicle entrance 11. In this embodiment, as shown in Figure 1, battery-equipped vehicles 34(34-1), 34(34-2), and 34(34-4) are parked as mobile vehicles. The symbols for the battery-equipped vehicles correspond to the symbols for the parking spaces, with battery-equipped vehicle 34(34-1) parked in parking space 12(12-1), battery-equipped vehicle 34(34-2) parked in parking space 12(12-2), and battery-equipped vehicle 34(34-4) parked in parking space 12(12-4).

[0090] Here, the parking facility 10 is a three-dimensional space whose position can be determined by coordinates of mutually orthogonal X, Y, and Z axes, with the Y axis being the height direction (up and down direction), the Z axis being the front-to-back direction with the vehicle entrance / exit 11 side being the rear side, and the X axis being the left-to-right direction. This point is the same as in Figures 8 to 11. When parking spaces 12(12-1) to 12(12-6) are not distinguished, they are referred to as parking space 12, and when battery-carrying vehicles 34(34-1), 34(34-2), and 34(34-4) are not distinguished, they are referred to as battery-carrying vehicles 34. In addition, each of the parking spaces 12 in which a vehicle is parked in this embodiment corresponds to a protected area of ​​the area to be protected.

[0091] The battery-equipped vehicle 34 is a vehicle equipped with a battery unit containing a high-voltage battery housing multiple lithium-ion batteries. Each of the parking spaces 12(12-1) to 12(12-6) is also equipped with charging facilities for charging the battery unit mounted on the battery-equipped vehicle 34, but these are not shown in the illustration.

[0092] Multiple water spraying heads (fire extinguishing liquid spraying heads) 14 are embedded in the floor (underside) of the parking space 12, with the water spraying direction facing upward. In this embodiment, as shown in Figure 2, water supply pipes 16 are laid in three rows in the front-to-back direction in one parking space 12, and multiple water spraying heads 14 are connected to the water supply pipes 16 in each row at predetermined intervals, for example, eight water spraying heads at predetermined intervals within the range of 50 to 100 cm. The reason why the water spraying heads 14 are embedded in the floor of the parking space 12 is that the battery unit is mounted on the bottom side of the battery-equipped vehicle 34 parked in the parking space 12, but they are not limited to being embedded in the floor and may be installed on the ceiling side, for example.

[0093] Furthermore, the water spraying performance of the water spraying head 14 is arbitrary, as long as it has the water spraying performance to cool and extinguish the fire by spraying fire-extinguishing water onto the battery section in the battery section of the battery-equipped vehicle 34 in the event of a fire caused by thermal runaway of the lithium-ion battery in the battery section. For example, the water discharge pressure is set to a predetermined value in the range of 0.1 to 1.0 MPa, and the water discharge flow rate is set to a predetermined value in the range of 80 to 100 liters / minute.

[0094] In this embodiment, since 24 water spray heads 14 are embedded in one parking space 12, if the water discharge rate of one water spray head 14 is 100 liters / minute, the total amount of water discharged in one parking space 12 becomes 2400 liters / minute, enabling the discharge of a sufficient amount of firefighting water. Furthermore, the number of water spray heads 14 is arbitrary; for example, if the number is doubled to 48, the total amount of water discharged becomes 4800 liters / minute.

[0095] Furthermore, since the water spraying head 14 is oriented upwards, a protective cap or protective plate is attached to the water outlet to protect it. When firefighting water is supplied to the water spraying head 14, the protective cap or protective plate is removed and the spraying of firefighting water begins.

[0096] Water supply pipes 20 are laid on the ceiling (upper) side of the parking facility 10 so as to surround each parking space 12, and water curtain forming heads 18 are connected to the water supply pipes 20 at predetermined intervals so as to surround each parking space 12, with the water spraying direction facing downward.

[0097] The water curtain forming head 18 forms a water curtain around any parking space 12 by spraying fire-extinguishing water. The water spraying performance of the water curtain forming head 18 is arbitrary, as long as it is possible to form a water curtain that can suppress and prevent the propagation of radiant heat from a fire to other parking spaces 12. For example, the water discharge pressure is set to a predetermined value in the range of 0.1 to 1.0 MPa, and the water discharge flow rate is set to about 10 liters / minute. The installation interval of the water curtain forming heads 18 is set to a predetermined interval so that the water curtains formed by the water sprayed from adjacent water curtain forming heads 18 overlap each other and no gaps are formed between the water curtains formed by the water sprayed from each water curtain forming head 18.

[0098] Furthermore, each branch connection of the water supply pipe 20 is equipped with a remote on / off valve 22, and the remote on / off valve 22 is controlled to open and close in order to supply firefighting water to the water curtain forming head 18 corresponding to the parking area 12 that forms the water curtain. The area surrounded by the water curtain formed by the water spraying from the water curtain forming head 18 is called a fire-resistant area.

[0099] Furthermore, an electrostatic spraying head 26 is installed on the ceiling side of the parking space 12, and the electrostatic spraying head 26 is connected to the same water supply piping 20 as the water curtain forming head 18. The electrostatic spraying head 26 is capable of spraying charged liquid particles, which are made by charging liquid particles of fire extinguishing water, onto the corresponding parking space 12, and the spraying direction and spread of the charged liquid particles are set so that the corresponding parking space 12 is within the spraying area.

[0100] Furthermore, a high-voltage power supply unit (voltage supply unit) 36 is provided for the charged spraying head 26. The high-voltage power supply unit 36 ​​supplies a predetermined high voltage to the charged spraying head 26 so that when the charged spraying head 26 sprays charged liquid particles, the charged liquid particles have the opposite polarity to the charged polarity of the smoke generated by a fire caused by thermal runaway of a lithium-ion battery. As a result, the charged liquid particles are efficiently adsorbed to the smoke particles by electrostatic force, causing the smoke to settle quickly and efficiently, thereby ensuring the visibility necessary for evacuation, protecting people from toxic substances, and reliably reducing casualties.

[0101] Furthermore, since a runaway thermal event in a lithium-ion battery generates gases containing hydrogen, carbon monoxide, methane, carbon dioxide, and hydrocarbons, a carbon dioxide sensor 28, a carbon monoxide sensor 30, and a hydrogen sensor 32 are installed on the ceiling side of the parking space 12 as an abnormality detection unit to detect fires caused by a runaway thermal event in the lithium-ion battery of the battery unit installed in the battery-carrying vehicle 34. These sensors are connected to system control panels (control units) 50(50-1) and 50(50-2) by signal cables 54.

[0102] (a2. System control panel and pressurized water supply equipment) Next, we will describe the system control panel, which functions as the control unit, and the pressurized water supply equipment that supplies firefighting water to the water spraying head, water curtain forming head, and electrostatic spraying head. For this description, please refer to Figures 1 and 2.

[0103] In this embodiment, the system control panel 50(50-1) and the system control panel 50(50-2) are configured to communicate with each other, with the system control panel 50(50-1) controlling the fire monitoring of parking spaces 12(12-1) to 12(12-3), and the system control panel 50(50-2) controlling the fire monitoring of protected spaces 12(12-4) to 12(12-6).

[0104] Therefore, the carbon dioxide sensors 28, carbon monoxide sensors 30, and hydrogen sensors 32 in parking spaces 12(12-1) to 12(12-3) are connected to the system control panel 50(50-1) by signal cables 55, while the carbon dioxide sensors 28, carbon monoxide sensors 30, and hydrogen sensors 32 in parking spaces 12(12-4) to 12(12-6) are connected to the system control panel 50(50-2) by signal cables 55.

[0105] Furthermore, in this embodiment, the system control panels 50(50-1) and 50(50-2) determine that a fire (abnormality) has occurred when all of the carbon dioxide sensor 28, carbon monoxide sensor 30, and hydrogen sensor 32 satisfy predetermined detection conditions, for example, when the signal levels of all sensor detection signals from each sensor are above or above a predetermined threshold.

[0106] Furthermore, the system control panel 50(50-1) controls the spraying operation of the water spraying heads 14 in the parking spaces 12(12-1) to 12(12-6), and the system control panel 50(50-2) controls the spraying operation of the water curtain forming heads 18 and the electrostatic spraying heads 26 in the protected areas 12(12-1) to 12(12-6).

[0107] Furthermore, a first pressurized water supply system 15(15-1) is provided as a pressurized water supply system to supply firefighting water to the water spraying heads 14 in parking spaces 12(12-1) to 12(12-6), and a second pressurized water supply system 15(15-2) is provided as a pressurized water supply system to supply firefighting water to the water curtain forming heads 18 and the electrostatic spraying heads 26 in protected areas 12(12-1) to 12(12-6).

[0108] The first pressurized water supply equipment 15 (15-1) is equipped with a motor 38 (38-1), a pump 40 (40-1), a fire extinguishing water source tank 42 (42-1), and a pump control panel 52 (52-1). A water supply pipe 16 to which a water spray head 14 is connected is connected to the main water supply pipe 44 drawn from the pump 40 (40-1) via a simultaneous release valve 46 (46-1). An electric start valve 48 (48-1) is provided for the simultaneous release valve 46 (46-1), and the electric start valve 48 (48-1) is connected to a signal line from the system control panel 50 (50-1). Furthermore, the simultaneous release valve 46 (46-1) is provided at each branch point of the water supply pipe 16 to each parking space 12, allowing control of the supply and cessation of fire extinguishing water for each parking space 12.

[0109] The second pressurized water supply equipment 15 (15-2) is equipped with a motor 38 (38-2), a pump 40 (40-2), a fire extinguishing water source tank 42 (42-2), and a pump control panel 52 (52-2). In addition, a water supply pipe 20 is connected to the main water supply pipe 54 drawn out from the pump 40 (40-2), to which a water curtain forming head 18 and an electrostatic spraying head 26 are connected, and a remote on / off valve 22 is provided at the branch connection point.

[0110] Furthermore, a manual selector valve 24 is provided near the vehicle entrance / exit 11 of the parking facility 10, for example, which functions as a manual operation unit that allows for the operation of spraying fire-fighting water from a water curtain forming head 18 to form a water curtain. The manual selector valves 24 are, for example, separate manual selector valves 24 for the left parking spaces 12(12-1) to 12(12-3) and the right parking spaces 12(12-4) to 12(12-6). If a water curtain is not formed due to a malfunction of the remote on / off valve 22, it is possible to start and stop water spraying from the water curtain forming head 18 corresponding to the parking space 12 to which the water curtain is to be formed by operating either manual selector valve 24. Furthermore, the manual selection valve 24 may not be provided separately for the left parking spaces 12(12-1) to 12(12-3) and the right parking spaces 12(12-4) to 12(12-6), but rather may be provided corresponding to each of the parking spaces 12(12-1) to 12(12-6), or it may be provided in any other way that divides the spaces.

[0111] (a3. Structure of the electrostatic dispersal head) Next, the structure of the electrostatic spraying head will be explained. Refer to Figure 3, which shows the structure of the electrostatic spraying head, for this explanation. Note that in Figure 3, the spraying side is considered the bottom, Figure 3(A) shows a perspective view of the spraying head from below, and Figure 3(B) shows a cross-sectional view from the side.

[0112] The electrostatic spraying head 26, as shown in Figure 3 for example, consists of a body 2610, a spraying nozzle section 2620, an electrode holding section 2630, an induction electrode section 2640, a water-side electrode section 2650, and a pipe connection section 2660. The body 2610, spraying nozzle section 2620, electrode holding section 2630, and pipe connection section 2660 are made of insulating material.

[0113] The electrostatic spraying head 26 is assembled by first fitting a conductive water-side electrode section 2650 from below into a through hole formed inside the body 2610 along the direction of the spraying axis 2670, then fitting a pipe connection section 2660 above the water-side electrode section 2650 and a spray nozzle section 2620 below the water-side electrode section 2650, and finally attaching an induction electrode section 2640 to the open space below the spray nozzle section 2620 by an electrode holding section 2630. The configuration and structure of the induction electrode section 2640 are arbitrary, but for example, it is a ring shape formed by insulating a conductive electrode core material.

[0114] Furthermore, a water supply pipe 20 is connected to the pipe connection section 2660, and pressurized fire extinguishing water is supplied to the pipe connection section 2660 from the second pressurized water supply equipment 15 (15-2), causing liquid particles with an average particle diameter of, for example, about 100 to 300 μm to be sprayed from the spray nozzle section 2620.

[0115] Furthermore, high-voltage cables are connected to the cable connection portion 2642 of the induction electrode portion 2640 and the electrode connection portion 2652 of the water-side electrode portion 2650. Between the induction electrode portion 2640 and the water-side electrode portion 2650, a predetermined voltage (e.g., a DC voltage of 10kV) is applied from the high-voltage power supply 36, adjusted within a predetermined adjustment range (e.g., 0.5kV to 20kV) within a voltage range capable of charging liquid particles. This applied voltage creates a predetermined external electric field around the ring portion of the induction electrode portion 2640, and liquid particles sprayed from the spray nozzle portion 2620 are charged by the induction charging method as they pass through the ring portion of the induction electrode portion 2640.

[0116] Here, the predetermined adjustment range within the voltage range in which liquid particles can be charged may include a voltage range in which liquid particles cannot be charged, and it is sufficient that the voltage can be adjusted to a predetermined voltage in which liquid particles can be charged. In addition, the voltage polarity (positive / negative) of the applied voltage can be switched by the high-voltage power supply 36.

[0117] The charging of liquid particles in the charged spraying head 26 can be achieved by, for example, applying a predetermined DC voltage that makes the potential of the induction electrode 2640 positive, with the water-side electrode 2650 as the reference potential (earth potential, 0V). In this case, the liquid particles sprayed from the charged spraying head 26 will be negatively charged. Alternatively, applying a predetermined DC voltage that makes the potential of the induction electrode 2640 negative, with the water-side electrode 2650 as the reference potential (earth potential, 0V), will cause the liquid particles sprayed from the spraying nozzle 2620 to be positively charged. Furthermore, by setting the absolute value of the voltage applied between the induction electrode 2640 and the water-side electrode 2650 to, for example, a range of 0.5kV to 20kV, the generation of spark discharge is prevented, and charged liquid particles are generated while ensuring safety.

[0118] Furthermore, the configuration and structure of the charged spraying head 26 are arbitrary and are not limited to the charged spraying head 26 shown in Figure 3. Any suitable structure or known structure capable of generating liquid particles and simultaneously charging the generated liquid particles for spraying as charged liquid particles is included. Also, the voltage applied between the induction electrode section 2640 and the water-side electrode section 2650 is not limited to a DC voltage; a pulse voltage, pulsating voltage, or AC voltage may be applied.

[0119] (a4. Configuration of the high-voltage power supply unit) Next, the configuration of the high-voltage power supply unit will be described. In this description, please refer to Figure 4, which shows the configuration of the high-voltage power supply unit together with the electrostatic dispersal head.

[0120] The high-voltage power supply unit 36 ​​supplies the voltage necessary to generate charged liquid particles in the charged spraying head 26 via a high-voltage cable 35. Its configuration and functions are arbitrary, but for example, as shown in Figure 4, it includes a high-voltage variable circuit 3610 for adjusting the supplied voltage and a polarity reversal circuit 3620 for switching the voltage polarity of the supplied voltage. The high-voltage cable 35 is referred to as the voltage application cable 3510, which is connected to the induction electrode section 2640 side of the charged spraying head 26, and the cable connected to the water side electrode section 2650 side is referred to as the earth cable 3520.

[0121] A voltage application cable 3510 connected to the polarity reversal circuit 3620 of the high-voltage power supply unit 36 ​​is connected to the induction electrode portion 2640 of the charged spraying head 26 via a current limiting resistor 3630, and an earth cable 3520 connected to the polarity reversal circuit 3620 of the high-voltage power supply unit 36 ​​is connected to the water-side electrode portion 2650 of the charged spraying head 26. As a result, when a predetermined high voltage is applied between the induction electrode portion 2640 and the water-side electrode portion 2650, the liquid particles sprayed from the charged spraying head 26 are charged. Here, the voltage application cable 3510 and the earth cable 3520 are high-insulation, voltage-resistant cables. However, when applying only a DC voltage, the positive cable may be a voltage-resistant cable and the negative cable may be a normal low-voltage cable.

[0122] The high-voltage variable circuit 3610 adjusts the voltage applied between the induction electrode section 2640 and the water-side electrode section 2650 in response to a control signal transmitted from the system control panel 50 (50-2) via the signal cable 55. This allows the charged liquid particles with an appropriate charge level for fire extinguishing and smoke suppression to be sprayed from the charged spraying head 26. Furthermore, by reducing the absolute value of the applied voltage to create charged liquid particles with a reduced charge level, it is possible to prevent discharge accidents caused by an increase in the charge level that could occur in fire-extinguishing targets that are prone to becoming charged.

[0123] The polarity reversal circuit 3620 switches the voltage polarity of the voltage output from the high-voltage variable circuit 3610 in response to a control signal transmitted from the system control panel 50 (50-2) via the signal cable 55. This switches the charge polarity of the charged liquid particles sprayed from the charged spraying head 26, allowing for the spraying of charged water particles with a charge polarity suitable for fire extinguishing, smoke suppression, etc. Note that the voltage polarity switching by the polarity reversal circuit 3620 is not always performed, but is done as needed. Furthermore, if the object to be extinguished, the object to be protected from fire, the object to be smoke suppressed, etc., is charged or easily becomes charged, a higher fire extinguishing and smoke suppression effect can be expected by spraying charged liquid particles with the opposite polarity to the object's charge polarity.

[0124] [b. Fire characteristics of lithium-ion batteries] Next, we will explain the fire characteristics of lithium-ion batteries. For this explanation, please refer to Figure 5, which shows the change in smoke concentration over time in a fire experiment involving a lithium-ion battery; Figure 6, which shows the change in the charge polarity of the flame generated in the same experiment; and Figure 7, which also shows the change in the charge polarity of the smoke generated in the same experiment.

[0125] The lithium-ion battery fire experiment was conducted by heating an 18650 type lithium-ion battery with a gas burner in a sealed stainless steel space of a predetermined size. When the lithium-ion battery was heated with a gas burner, white smoke (electrolyte vapor) was emitted from the positive electrode, the emitted white smoke ignited and the entire battery was engulfed in flames, and then the flames subsided and a large amount of white smoke was emitted from the positive electrode.

[0126] (b1. Smoke concentration and sedimentation velocity) First, we will explain the smoke concentration and settling velocity obtained from the lithium-ion battery fire experiment. In the fire experiment, a dimming densitometer was placed at a predetermined height in a sealed space to measure the smoke concentration, and a graph showing the change in smoke concentration over time, as shown in Figure 5, was obtained. Note that in the graph in Figure 5, the smoke concentration is expressed as the dimming rate Cs(1 / m). In order to equalize the smoke concentration in the sealed space during the measurement of the smoke concentration, the smoke was stirred using a stirring fan.

[0127] As shown in Figure 5, the smoke concentration rises sharply when the flame is extinguished and a large amount of white smoke is released from the positive electrode. However, when the smoke is stirred to equalize the smoke concentration in the sealed space, the attenuation rate Cs is approximately 0.5 to 0.7 (1 / m), and even after time has passed, the smoke concentration (attenuation rate Cs) has hardly changed. This indicates that the smoke generated in the lithium-ion battery fire experiment hardly settles naturally, and this was confirmed to be the case when compared to the natural settling of cellulose-based and hydrocarbon-based smokes.

[0128] Furthermore, the white smoke contains combustion product gases, mainly hydrogen, carbon monoxide, methane, carbon dioxide, and VOCs, which are generated by the thermal runaway of lithium-ion batteries. It is thought that the reason for this is that the terminal velocity of the volatile white smoke is slow, and it is hardly affected by gravity sedimentation resistance.

[0129] Therefore, if a lithium-ion battery in a battery-equipped vehicle 34 parked in the parking facility 10 overheats and causes a fire, white smoke will rapidly spread throughout the parking facility 10 and remain in the atmosphere for a long time. If any people remain in the parking facility 10, their visibility will be obstructed, severely limiting their evacuation, and they will be exposed to highly toxic combustion gases, which could cause significant casualties.

[0130] (b2. Charge polarity of flame and smoke) Next, we will explain the charge polarity of flames and smoke obtained from fire experiments with lithium-ion batteries. In the fire experiments, a suction-type Faraday cage was placed on top of a lithium-ion battery in a sealed space, and the charge polarity of the flames and smoke was measured. A graph showing the time change of the charge polarity of the flame, as shown in Figure 6, and a graph showing the time change of the charge polarity of the smoke, as shown in Figure 7, were obtained.

[0131] In a fire experiment involving a lithium-ion battery, when the emitted white smoke ignited and the entire battery was engulfed in flames, the charge polarity of the flame was measured. As shown in Figure 6, it was confirmed that the flame had a positive charge polarity. Furthermore, when the charge polarity of the smoke was measured when a large amount of white smoke was emitted from the positive electrode, it was confirmed that the smoke had a negative charge polarity. As shown in Figure 7, the charge polarity of the smoke was negative.

[0132] Therefore, in order to remove smoke generated by a fire caused by thermal runaway of a lithium-ion battery, it is appropriate to spray positively charged liquid particles from the charged spraying head 26. In order to spray positively charged liquid particles from the charged spraying head 26, the system control panel 50 (50-2) controls the high-voltage power supply unit 36 ​​to apply a predetermined voltage so that the potential of the induction electrode unit 2640 becomes negative, with the water-side electrode unit 2650 of the charged spraying head 26 set to a reference potential (earth potential, 0V).

[0133] Furthermore, by spraying positively charged liquid particles from the charged spraying head 26, the charged liquid particles efficiently adhere to negatively charged smoke particles through electrostatic force, causing the smoke to settle quickly and efficiently, thereby securing the visibility necessary for evacuation, protecting people from toxic substances, and reliably reducing casualties.

[0134] [c. Operation of protective equipment] Next, the operation of the protective equipment will be explained. In this explanation, please refer to Figure 8, a front view showing the protective equipment in operation when a fire occurs in a battery-equipped vehicle due to thermal runaway of a lithium-ion battery, and Figure 9, a top view showing the protective equipment in operation when a fire occurs in a battery-equipped vehicle due to thermal runaway of a lithium-ion battery. Furthermore, the operation of the protective equipment will be explained using the example of a fire occurring in the battery section of battery-equipped vehicle 34 (34-1) parked in parking space 12 (12-1), due to thermal runaway of the lithium-ion battery. In Figure 8, battery-equipped vehicle 34 (34-2) is omitted in order to represent the situation in parking space 12 (12-1).

[0135] As shown in Figure 8, if a fire occurs in a battery-equipped vehicle 34 (34-1) parked in parking space 12 (12-1) due to thermal runaway of the lithium-ion battery in the battery section, all of the sensor detection signals transmitted from the carbon dioxide sensor 28, carbon monoxide sensor 30, and hydrogen sensor 32 installed on the ceiling side of parking space 12 (12-1) will satisfy the predetermined detection conditions, and the system control panel 50 (50-1) will determine that there is a fire in parking space 12 (12-1).

[0136] The system control panel 50 (50-1), having determined that there is a fire in parking space 12 (12-1), sends a pump start signal to the pump control panel 52 (52-1) of the first pressurized water supply equipment 15 (15-1). Upon receiving the pump start signal, the pump control panel 52 (52-1) drives the motor 38 (38-1) to start the pump 40 (40-1) and supplies pressurized firefighting water from the firefighting water source tank 42 (42-1) to the main water supply pipe 44.

[0137] Furthermore, the system control panel 50 (50-1) controls the opening of the starting electric valve 48 (48-1) corresponding to the parking space 12 (12-1), thereby driving the simultaneous opening valve 46 (46-1) corresponding to the parking space 12 (12-1) to open. As shown by the shaded area of ​​the parking space 12 (12-1) in Figure 9, the water spraying head 14 embedded in the floor of the parking space 12 (12-1) sprays fire-extinguishing water upwards, cooling and extinguishing the battery section located on the bottom of the battery-equipped vehicle 34 (34-1) where the fire is occurring. Note that in Figures 8 and 9, the water supply pipe 16 to which the fire-extinguishing water is supplied is shown by a thick line.

[0138] Meanwhile, the system control panel 50 (50-2) receives notification from the system control panel 50 (50-1) that there is a fire in the parking space 12 (12-1), and sends a pump start signal to the pump control panel 52 (52-2) of the second pressurized water supply equipment 15 (15-2). Upon receiving the pump start signal, the pump control panel 52 (52-2) drives the motor 38 (38-2) to start the pump 40 (40-2), and supplies pressurized firefighting water from the firefighting water source tank 42 (42-2) to the main water supply pipe 54.

[0139] Furthermore, as shown in Figure 9, the system control panel 50 (50-2) controls the remote on-off valve 22 so that fire extinguishing water is sprayed from the water curtain forming head 18 installed to surround the parking space 12 (12-1). As shown by the shaded area of ​​the parking space 12 (12-1) in Figure 9, the fire extinguishing water is sprayed downwards from the water curtain forming head 18 installed to surround the parking space 12 (12-1) to form a water curtain. By positioning the battery-equipped vehicle 34 (34-1) in the fire-resistant area formed by the water curtain, the propagation of radiant heat from the fire to other parking spaces is suppressed and prevented.

[0140] Furthermore, when forming a water curtain around the parking space 12 (12-1), as shown in Figure 9, the system control panel 50 (50-2) controls the closing of three remote on / off valves 22, which are shown in black, thereby supplying firefighting water to the locations of the water supply pipes 20 indicated by thick lines, and the firefighting water is sprayed from the water curtain forming heads 18 installed around the parking space 12 (12-1).

[0141] Furthermore, the system control panel 50 (50-2) sends a control signal to the high-voltage power supply unit 36 ​​of the charged spraying head 26 corresponding to the parking space 12 (12-1), and applies a predetermined voltage to the charged spraying head 26 such that the potential of the induction electrode 2640 becomes negative, with the water-side electrode 2650 of the charged spraying head 26 set to a reference potential (earth potential, 0V), causing the charged spraying head 26 to spray positively charged liquid particles.

[0142] Furthermore, while a fire compartment is formed in parking space 12(12-1) using the water curtain forming head 18, the location where the fire compartment is formed is arbitrary. For example, a fire compartment may also be formed in parking space 12(12-2), which is adjacent to parking space 12(12-1) that has been determined to be on fire, by spraying fire-extinguishing water from the water curtain forming head 18. Alternatively, a fire compartment may be formed in all of the parking spaces 12(12-1) to 12(12-3) located on the left side.

[0143] Furthermore, in this embodiment, the system control panel 50(50-1) and 50(50-2) are used to control fire monitoring and the spraying operation of the water spraying head 14, water curtain forming head 18, and electrostatic spraying head 26, but all of these controls may be performed by a single system control panel.

[0144] [d. Second embodiment of protective equipment] Next, a second embodiment of the protective equipment will be described. In this description, refer to Figure 10, which shows a front view (viewed from the front) of the second embodiment of the protective equipment, and Figure 11, which shows a top view (viewed from above) of the second embodiment of the protective equipment.

[0145] The second embodiment of the protective equipment is characterized by having a drainage structure that collects the fire-fighting water sprayed from the water spraying head 14, the water curtain forming head 18, and the electrostatic spraying head 26 into a wastewater recovery tank. The drainage structure comprises a drainage channel 56, a drainage pipe 58, a wastewater recovery tank 60, and a sewer inlet pipe 62. Since the protective equipment is basically the same as the first embodiment except for the inclusion of a drainage structure, the same reference numerals are used for other components and their descriptions are omitted.

[0146] As shown in Figure 11, the drainage structure 56 is laid in the front-to-back direction between the central passageway and the parking spaces 12, for example, on both the left and right sides of the central passageway that leads to the vehicle entrance / exit 11 of the parking facility 10. In addition, the floor surface of the parking facility 10 has a predetermined slope so that it slopes downward from both the left and right sides toward the center, so that the fire extinguishing water sprayed from the water spraying heads 14, water curtain forming heads 18 and electrostatic spraying heads 26 flows to the drainage channels 56.

[0147] Furthermore, as shown in Figure 10, the drainage channels 56 laid on both the left and right sides of the central passageway are connected to a wastewater recovery tank 60 by drainage pipes 58. Firefighting water sprayed from the water spraying heads 14, water curtain forming heads 18, and electrostatic spraying heads 26 is collected from the drainage channels 56 and stored in the wastewater recovery tank 60. After treatment such as filtration and dilution, the water is discharged into the sewer system through the sewer inlet pipe 62, thereby ensuring safety.

[0148] Furthermore, the wastewater recovery tank 60 does not have any treatment functions such as filtration or dilution, and may simply store the firefighting water that has been sprayed. In this case, the wastewater recovery tank 60 does not have a sewer inlet pipe 62 that connects to the sewer system, and the firefighting water stored in the wastewater recovery tank 60 is transported to a designated treatment facility for treatment.

[0149] [e. Third embodiment of protective equipment] Next, a third embodiment of the protective equipment will be described.

[0150] (e1. Configuration of protective equipment) First, the configuration of the protective equipment will be explained. In this explanation, refer to Figure 12, which shows a front view (viewed from the front) of the third embodiment of the protective equipment.

[0151] As shown in Figure 12, the third embodiment of the protective equipment is characterized by having a smoke detection device 70 instead of the carbon dioxide sensor 28, carbon monoxide sensor 30, and hydrogen sensor 32 as the abnormality detection unit. Since the protective equipment is basically the same as the first embodiment except for the inclusion of the smoke detection device 70, the same reference numerals are used for other components and their descriptions are omitted.

[0152] The smoke detection device 70 is capable of detecting the amount of charge in smoke generated by abnormalities such as thermal runaway of lithium-ion batteries. It determines whether the detected charge is the amount of charge in smoke generated by an abnormality, and if it determines that it is the amount of charge in smoke generated by an abnormality, it detects an abnormality and transmits an abnormality detection signal to the system control panels 50(50-1) and 50(50-2). For example, it is equipped with a rotary chopper type Faraday cage structure.

[0153] Furthermore, the smoke detection device 70, which is equipped with a rotary chopper-type Faraday cage structure, can also detect the charge polarity of smoke generated by abnormalities, and includes information on the charge polarity of the smoke in the abnormality detection signal transmitted to the system control panels 50(50-1) and 50(50-2). Therefore, upon receiving the abnormality detection signal, the system control panels 50(50-1) and 50(50-2) can control the spraying operation based on the information on the charge polarity of the smoke included in the abnormality detection signal, so that the charge polarity of the charged liquid particles sprayed from the charged spraying head 26 is the opposite of the charge polarity of the smoke detected by the smoke detection device 70, thereby efficiently adsorbing the charged liquid particles onto the smoke particles and rapidly causing the smoke to settle.

[0154] (e2. Configuration of the smoke detection device) Next, the configuration of the smoke detection device equipped with a rotary chopper-type Faraday cage structure will be described. In this description, refer to Figure 13, which shows the configuration of the smoke detection device, and Figure 14, which shows the main body of the smoke detection device. Note that in Figure 14, the orientation of the main body of the device is upside down compared to Figure 13, Figure 14(A) shows the view from the left side in Figure 13, Figure 14(B) shows the view from the same side as in Figure 13, and Figure 14(C) shows the view from the right side in Figure 13.

[0155] As shown in Figure 13, the smoke detection device 70 comprises a device body 72, a rotary drive unit 74, a connecting pipe 76, a charge detection unit 78, a suction unit 80, an operation control unit 82, and an abnormality determination unit 84.

[0156] The main body of the device 72 houses a rotating electrode, which will be described later. The rotation drive unit 74 of the rotating electrode is equipped with a motor 88 and three gears, including gears 9010 and 9012 that constitute the reduction unit 90.

[0157] The main body of the device 72 has air inlets and outlets 92 and 94 at both ends in the axial direction. In Figure 13, the suction unit 80 is connected to the left inlet / outlet 92 via a flexible connecting pipe 76 made of resin or rubber. The suction unit 80 houses a motor-driven blower inside and supplies air drawn in from the left intake port 8010 in Figure 13 to the main body of the device 72 via the connecting pipe 76. The air supplied to the main body of the device 72 passes through the inside of the main body of the device 72 and is discharged from the inlet / outlet 94. Alternatively, the suction unit 80 may be connected to the inlet / outlet 94 side, drawing in air from the monitoring area from the inlet / outlet 94, passing through the inside of the main body of the device 72, and discharging it from the inlet / outlet 92. The direction in which the air passes through the inside of the main body of the device 72 is not restricted.

[0158] The charge detection unit 78 is a functional unit realized by a circuit board located in a box-shaped circuit housing 79 located in the main body of the device 72. The charge detection unit 78 outputs a charge detection voltage signal corresponding to the amount of charge of smoke (smoke particles) contained in the passing air to the abnormality determination unit 84 from output terminals OUT1 and OUT2, based on the electrode structure within the main body of the device 72.

[0159] The abnormality determination unit 84 determines whether the detected charge amount is the amount of charge of smoke generated by an abnormality, based on the charge detection voltage signal output from the charge detection unit 78. If it determines that the amount of charge is the amount of charge of smoke generated by an abnormality, it senses an abnormality and outputs an abnormality detection signal to the system control panels 50(50-1) and 50(50-2) via the signal cable 55.

[0160] The operation control unit 82 controls the operations necessary for the operation of the smoke detection device 70. When power is supplied to the smoke detection device 70 via signal cables 55 from the system control panels 50(50-1) and 50(50-2), it outputs a drive signal to the motor 88 of the rotary drive unit 74 to rotate the rotating electrode located inside the device body 72 at a predetermined speed, and also outputs a drive signal to the suction unit 80 to start drawing in air and supply the drawn-in air to the device body 72. The device body 72 is also equipped with a rotation detector 86 that detects the rotation speed of the rotating electrode, and the operation control unit 82 controls the rotation speed by driving the motor 88 to eliminate the speed difference between the detection speed of the rotation detector 86 and a predetermined set speed. The operation control unit 82 and the abnormality determination unit 84 are functional units realized by circuit boards located inside the circuit housing unit 79, but for the sake of explanation, in Figure 13 the charge detection unit 78 is shown at the location of the circuit housing unit 79, and the operation control unit 82 and the abnormality determination unit 84 are shown at different locations.

[0161] As shown in Figure 14, the main body of the device 72 is, for example, a cylindrical metal body closed at both ends by a flange structure, and includes a box-shaped circuit housing 79 that houses a circuit board for realizing functional parts such as the charge detection unit 78. Therefore, it is installed near the ceiling of the parking facility 10 using the circuit housing 79 as a base. The orientation of the suction port 8010 of the suction unit 80 when installed is not limited, and for example, it may be installed facing downwards when installed in the parking facility 10.

[0162] (e3. Detailed structure of the smoke detection device) Next, the detailed structure of the smoke detection device will be described. In this description, please refer to Figure 15, which shows the internal structure of the smoke detection device; Figure 16, which shows the rotating electrode of the device body removed; Figure 17, which shows the cage electrode of the device body removed in an assembled and disassembled state; and Figure 18, which shows the details of the first gauge electrode and the second cage electrode that constitute the cage electrode.

[0163] In the explanation of Figure 15, the XYZ directions are mutually orthogonal. Specifically, when viewing the front of the device body 72 shown in Figure 15, the X direction is the left-right direction, the Y direction is the up-down direction, and the Z direction (towards the plane of the paper, not shown) is the front-back direction. Furthermore, in the X direction, the +X side is the right side and the -X side is the left side; in the Y direction, the +Y side is the upper side and the -Y side is the lower side; and in the Z direction, the +Z side is the front side and the -Z side is the rear side. This is the same in Figures 16 to 24. Although the XYZ directions are also defined in the parking facility 10, the XYZ directions defined in the parking facility 10 and the XYZ directions defined in the smoke detection device 70 do not necessarily coincide. Also, Figures 15 and 19 show the circuit configuration for realizing the charge detection unit 78 as the internal structure of the circuit housing 79, and this circuit is not restricted by the directions defined by the XYZ directions.

[0164] As shown in Figure 15, the main body of the device 72 is formed by connecting and fixing a flange member 98 to the left side of the cylindrical external electrode 106 to close it, and connecting and fixing a flange member 100 to the right side of the external electrode 116 to close it, thereby forming the outer casing of the main body of the device 72.

[0165] The flange members 98 and 100 have internal piping sections 9210 and 9410 integrally formed with externally protruding inlets and outlets 92 and 94. The internal piping sections 9210 and 9410 are arranged at a predetermined interval in the center, and a flue pipe 96, which functions as an insulating pipe member, is positioned between the opposing openings of the internal piping sections 9210 and 9410.

[0166] The flue pipe 96 is made of Teflon® resin. If the air passing through it contains charged smoke particles, the induced polarization of the charges of the charged smoke particles passing through the flue pipe 96 generates charges on the inner surface that are opposite in polarity to the charges of the charged smoke particles, while generating charges on the outer surface that are the same polarity as the charges of the charged smoke particles. For example, if the charged smoke particles have a positive charge (positive polarity), negative charges will be generated on the inner surface of the flue pipe 96, and positive charges will be generated on the outer surface. Also, if the charged smoke particles have a negative charge (negative polarity), positive charges will be generated on the inner surface of the flue pipe 96, and negative charges will be generated on the outer surface.

[0167] On the outside of the flue pipe 96, rotating electrodes 106 are rotatably arranged concentrically (coaxially) by bearings 102 and 104 located on both sides.

[0168] The rotating electrode 106 has the structure shown in Figure 16. Figure 16(A) shows a plan view, Figure 16(B) shows a cross-section along the cutting line aa in Figure 16(A), Figure 16(C) shows a cross-section along the cutting line bb in Figure 16(A), Figure 16(D) shows the left side view, and Figure 16(E) shows the right side view.

[0169] As shown in Figure 16, the rotating electrode 106 is a metallic cylindrical member with an internal passage 1064, and rectangular openings 1062 and 1063, which are elongated in the left-right direction, are opened on cylindrical surfaces 1060 that are opposite each other in the diametrical direction. A flange portion 1066 for connecting to the rotation drive unit is formed at the right end of the rotating electrode 106, and four screw holes 1068 are formed in the flange portion 1066. In addition, a grounding ring portion 1069 for grounding connection in the rotational state is formed on the outer circumferential surface of the left end of the rotating electrode 106.

[0170] The rotary drive unit 74 reduces the rotation of the motor 88 using the gears 9010, 9012, and 9014 of the reduction unit 90 and transmits it to the rotating electrode 106, which is rotatably supported by bearings 102 and 104. The rotational speed of the rotating electrode 106 is arbitrary, but for example, it rotates at 200 rpm.

[0171] In the rotating electrode 106, the region through which electric field lines pass due to the charge generated by induced polarization on the outer surface of the flue pipe 96 is restricted to rectangular openings 1062 and 1063. Since the positions of the rectangular openings 1062 and 1063 move with the rotation of the rotating electrode 106, the position through which the electric field lines pass also changes depending on the position of the rectangular openings 1062 and 1063.

[0172] Furthermore, a rotation detector 86 is provided on the left flange portion 98. The rotation detector 86 consists of a slit disc 8610 fixed to the left end of the rotating electrode 106 and a photointerrupter 8612 positioned between a light-receiving unit and a light-emitting unit so that the slit disc 8610 passes through it. The rotation detector 86 detects the rotation speed of the rotating electrode 106 in pulses and outputs it to the operation control unit 82.

[0173] Cage electrodes are arranged concentrically (coaxially) around the rotating electrode 106. The cage electrodes have the structure shown in Figures 17 and 18 and consist of a first cage electrode 108 and a second cage electrode 110. Figure 18(A) shows the plan view of the first and second cage electrodes in their assembled and disassembled states, Figure 18(B) shows the front view of the first and second cage electrodes in their assembled and disassembled states, Figure 18(C) shows the assembled state of the first and second cage electrodes, and Figure 18(D) shows the cross-section of the cutting line cc in Figure 18(C).

[0174] As shown in Figure 15, the first cage electrode 108 and the second cage electrode 110 are fixed concentrically (coaxially) on the outside of the rotating electrode 106 and are insulated and isolated from the inner rotating electrode 106 and the outer external electrode 116 by insulating rings 112 and 114.

[0175] As shown in Figures 17 and 18, the first cage electrode 108, which is fixedly positioned on the left side of the main body 72 of the apparatus, is a cylindrical metal member and has an electrode structure in which a pair of curved electrode pieces 1082 and 1084 are notched (extended) from the annular portion 1080 at the left end to the right.

[0176] The second cage electrode 110, which is fixedly positioned on the right side of the main body 72 of the device, is a cylindrical metal member and has an electrode structure in which a pair of curved electrode pieces 1102 and 1104 are notched (extended) from the annular portion 1100 at the right end to the left side.

[0177] The first cage electrode 108 and the second cage electrode 110 are positioned opposite each other and separated, for example, such that the curved electrode pieces 1102 and 1104 of the second cage electrode 110 are positioned between the curved electrode pieces 1082 and 1084 of the first cage electrode 108.

[0178] As electric field lines due to charges induced on the outer surface of the flue pipe 96 pass through the rectangular openings 1062 and 1063 of the rotating electrode 106, charges of the opposite polarity to those on the outer surface of the flue pipe 96 are generated by electrostatic induction in the portion of the cage electrode corresponding to the rectangular openings 1062 and 1063 of the rotating electrode 76. Since the region of the first cage electrode 108 opposite to the rectangular openings 1062 and 1063 changes periodically as the rectangular openings 1062 and 1063 rotate, the amount of induced charge induced in the first cage electrode 108 changes periodically.

[0179] Similarly, the same applies to the second cage electrode 110. The region of the second cage electrode 110 where the rectangular apertures 1062 and 1063 face each other changes periodically as the rectangular apertures 1062 and 1063 rotate. As a result, the amount of induced charge in the second cage electrode 110 also changes periodically.

[0180] Furthermore, since the curved electrode pieces 1102 and 1104 of the second cage electrode 110 are positioned at a 90° rotation around the left-right axis relative to the curved electrode pieces 1082 and 1084 of the first cage electrode 108, the periodic change in the amount of induced charge induced in the second cage electrode 110 has a 90° phase difference (time delay) compared to the periodic change in the amount of induced charge induced in the first cage electrode 108.

[0181] Here, the first cage electrode 108 and the second cage electrode 110 (cage electrodes) correspond to the inner Faraday cage in a rotating chopper type Faraday cage, the external electrode 116, which is grounded outside the cage electrodes, corresponds to the outer Faraday cage, and the rotating electrode 106 functions as a rotating chopper that alternately induces charges in the inner Faraday cage (cage electrodes) as the rectangular opening rotates.

[0182] (e4. Charge detection unit) Next, the charge detection unit will be described. For this description, please refer to Figure 19, which shows the area around the circuit housing in Figure 15 together with an oscilloscope.

[0183] The charge detection unit 78 is a functional unit realized by a circuit mounted on the circuit board 125. It outputs the potential difference between the first cage electrode 108 and the second cage electrode 110, each of which are electrostatically induced on the outer surface of the rotating electrode 106 as the charge corresponding to the charge of charged smoke particles contained in the air passing through the flue pipe 96 is generated, and the external electrode 116, as charge detection voltage signals V1 and V2.

[0184] The circuit section that outputs the charge detection voltage signal V1 (first charge detection circuit section) comprises an operational amplifier 122 and a feedback resistor 126. A grounded external electrode 116 is connected to the non-inverting input terminal (+ input terminal) of the operational amplifier 122 via an electrode pin 119, and a first cage electrode 108 is connected to the inverting input terminal (- input terminal) of the operational amplifier 122 via an electrode pin 118, as well as to the output terminal of the operational amplifier 122 via a feedback resistor 126.

[0185] When negative feedback is applied to the operational amplifier 122 via the feedback resistor 126, it performs an imaginary short circuit (virtual ground) so that the potential difference between the non-inverting input terminal (+ input terminal) and the inverting input terminal (- input terminal) becomes 0V. This converts the amount of induced charge at the first cage electrode 108 into a charge detection voltage signal V1, which is output from OUT1.

[0186] Furthermore, since the amount of induced charge at the first cage electrode 108 changes sinusoidally in synchronization with the rotation of the rotating electrode 106, the charge detection voltage signal V1 also changes sinusoidally. For example, when the charge detection voltage signal V1 is input to an oscilloscope 130 and observed when positively charged smoke particles pass through the flue pipe 96, a sinusoidal waveform 132 is obtained, as shown by the solid line on the screen of the oscilloscope 130 in Figure 19.

[0187] The circuit section that outputs the charge detection voltage signal V2 (second charge detection circuit section) is basically the same as the first charge detection circuit section, and includes an operational amplifier 124 and a feedback resistor 128. The grounded external electrode 116 is connected to the non-inverting input terminal (+ input terminal) of the operational amplifier 124 via electrode pin 121, and the second cage electrode 110 is connected to the inverting input terminal (- input terminal) of the operational amplifier 124 via electrode pin 120, and is also connected to the output terminal of the operational amplifier 124 via the feedback resistor 128.

[0188] When negative feedback is applied to the operational amplifier 124 via the feedback resistor 128, it performs an imaginary short circuit (virtual ground) so that the potential difference between the non-inverting input terminal (+ input terminal) and the inverting input terminal (- input terminal) becomes 0V. This converts the amount of induced charge at the second cage electrode 110 into a charge detection voltage signal V2, which is output from OUT2.

[0189] Furthermore, since the amount of induced charge of the second cage electrode 110 also changes sinusoidally in synchronization with the rotation of the rotating electrode 106, the charge detection voltage signal V2 also changes sinusoidally, and the charge detection voltage signal V2 has a phase difference of 90° with respect to the charge detection voltage signal V1. For example, when the charge detection voltage signal V2 is input to an oscilloscope 130 and observed when positively charged smoke particles pass through the flue pipe 96, a sinusoidal waveform 134 is obtained, as shown by the dotted line on the screen of the oscilloscope 130 in Figure 19.

[0190] Furthermore, if the rotational speed of the rotating electrode 106 is 200 rpm, for example, the charge detection voltage signals V1 and V2 will be observed as sinusoidal waveforms with a frequency of 3.3 Hz.

[0191] (e5. Rotational position of the rotating electrode and charge generation of the cage electrode) Next, the rotational position of the rotating electrode and the charge generation of the cage electrode will be explained. In this explanation, refer to Figure 20, which shows the rotational position of the rotating electrode relative to the flue pipe and cage electrode, which are fixedly arranged concentrically (coaxially), divided into rotational positions of 0°, 45°, 90°, and 135°; Figure 21, which shows the charge distribution of the flue pipe and cage electrode at the rotational position of the rotating electrode at 0°; Figure 22, which shows the charge distribution of the flue pipe and cage electrode at the rotational position of the rotating electrode at 45°; Figure 23, which shows the charge distribution of the flue pipe and cage electrode at the rotational position of the rotating electrode at 90°; Figure 24, which shows the charge distribution of the flue pipe and cage electrode at the rotational position of the rotating electrode at 135°; and Figure 25, which shows the charge detection voltage signal that changes sinusoidally in correspondence with the rotational position of the rotating electrode in Figures 21 to 24.

[0192] Figures 20(A) to (D) show the rotational positions of the rotating electrode 106 divided into 0°, 45°, 90°, and 135°, and a marker 105 indicating the rotational position of the rotating electrode 106 is shown for clarity of explanation.

[0193] In Figure 20(A), when the rotation position of the rotating electrode 106 is 0°, the rectangular openings 1062 and 1063 of the rotating electrode 106 are located above and below the curved electrode pieces 1082 and 1084, which are positioned above and below the fixed first cage electrode 108. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 is maximized, and the amount of induced charge induced in the curved electrode pieces 1082 and 1084 is maximized.

[0194] On the other hand, the rectangular openings 1062 and 1063 of the rotating electrode 106 do not face the curved electrode pieces 1102 and 1104 located before and after the fixedly positioned second cage electrode 110. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1102 and 1104 is minimized (determined as zero in this case), and the amount of induced charge in the curved electrode pieces 1102 and 1104 is zero.

[0195] At the rotational position of the rotating electrode 106 at 45° as shown in Figure 20(B), a portion (approximately half) of the rectangular openings 1062 and 1063 of the rotating electrode 106 faces the curved electrode pieces 1082 and 1084 located above and below the fixedly positioned first cage electrode 108. As a result, the area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 is reduced to approximately half of its maximum value, and the amount of induced charge induced in the curved electrode pieces 1082 and 1084 is also reduced from the maximum amount of induced charge to approximately half of the maximum amount of induced charge.

[0196] On the other hand, a portion (approximately half) of the rectangular openings 1062 and 1063 of the rotating electrode 106 faces the curved electrode pieces 1102 and 1104 located before and after the fixedly positioned second cage electrode 110. As a result, the area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1102 and 1104 increases from zero to approximately half of the maximum area, and the amount of induced charge induced in the curved electrode pieces 1102 and 1104 also increases from zero to approximately half of the maximum induced charge amount.

[0197] In the rotation position of the rotating electrode 106 shown in Figure 20(C), the rectangular openings 1062 and 1063 of the rotating electrode 106 do not face the curved electrode pieces 1082 and 1084 located above and below the fixedly positioned first cage electrode 108. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 is minimized (determined as zero in this case), and the amount of induced charge in the curved electrode pieces 1082 and 1084 is zero.

[0198] On the other hand, the rectangular openings 1062 and 1063 of the rotating electrode 106 are located in the same positions in front of and behind the curved electrode pieces 1102 and 1104, which are located in front of and behind the fixedly positioned second cage electrode 110. As a result, the area of ​​contact between the rectangular openings 1062 and 1063 and the curved electrode pieces 1102 and 1104 is maximized, and the amount of induced charge induced in the curved electrode pieces 1102 and 1104 is maximized.

[0199] At the rotation position of the rotating electrode 106 at 135° shown in Figure 20(D), a portion (approximately half) of the rectangular openings 1062 and 1063 of the rotating electrode 106 faces the curved electrode pieces 1082 and 1084 located above and below the fixedly positioned first cage electrode 108. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 increases to approximately half of the maximum area, and the amount of induced charge induced in the curved electrode pieces 1082 and 1084 also increases from zero to approximately half of the maximum induced charge amount.

[0200] On the other hand, a portion (approximately half) of the rectangular openings 1062 and 1063 of the rotating electrode 106 faces the curved electrode pieces 1102 and 1104 located before and after the fixedly positioned second cage electrode 110. As a result, the area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1102 and 1104 is reduced to approximately half of its maximum value, and the amount of induced charge induced in the curved electrode pieces 1102 and 1104 is also reduced from the maximum amount of induced charge to approximately half of its maximum value.

[0201] Then, when the rotating electrode 106 rotates another 45° clockwise from the state shown in Figure 20(D), it returns to the same state as in Figure 20(A), and thereafter the states shown in Figures 20(A) to (D) are repeated in sequence.

[0202] Next, the rotational position of the rotating electrode and the charge generation of the cage electrode will be explained in detail with reference to Figures 21 to 25. Note that Figures 21 to 25 describe the case where positively charged smoke particles pass through the flue pipe 96.

[0203] Figure 21 shows the case where the rotating electrode 106 shown in Figure 20(A) is at a rotational position of 0°. Due to the induced polarization of the insulator flue pipe 96 based on the positive charge of the charged smoke particles passing through the flue pipe 96, a negative charge is induced on the inner surface of the flue pipe 96 and a positive charge is induced on the outer surface.

[0204] At this time, the rectangular openings 1062 and 1063 of the rotating electrode 106 face the curved electrode pieces 1082 and 1084 of the first cage electrode 108, and the area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 is maximized. Due to electrostatic induction, a negative charge corresponding to the maximum induced charge amount is induced on the inner surface of the curved electrode pieces 1082 and 1084, and a positive charge is induced on the outer surface. Therefore, as shown in Figure 25, at a rotation position of 0°, the charge detection voltage signal V1 output from the first charge detection circuit unit becomes a peak value Vp corresponding to the maximum induced charge amount.

[0205] In contrast, the rectangular openings 1062 and 1063 of the rotating electrode 106 do not face the curved electrode pieces 1102 and 1104 of the second cage electrode 110. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1102 and 1104 is minimized (determined as zero in this case). As a result, the electric field lines due to the positive charge induced on the outer surface of the flue pipe 96 are blocked by the cylindrical surface 1060 of the rotating electrode 106 and do not pass through, resulting in zero induced charge on the curved electrode pieces 1102 and 1104. Therefore, as shown in Figure 25, at a rotation position of 0°, the charge detection voltage signal V2 output from the second charge detection circuit is at its minimum value of 0V.

[0206] Next, Figure 22 shows the case where the rotating electrode 106 shown in Figure 20(B) is positioned at a rotational position of 45°. The rectangular openings 1062 and 1063 of the rotating electrode 106 face a portion (approximately half) of the curved electrode pieces 1082 and 1084 of the first cage electrode 108 and a portion (approximately half) of the curved electrode pieces 1102 and 1104 of the second cage electrode 110. The induced dielectric charge of the curved electrode pieces 1082 and 1084 decreases from the maximum dielectric charge to approximately half of the maximum dielectric charge, while the induced dielectric charge of the curved electrode pieces 1102 and 1104 increases from zero to approximately half of the maximum dielectric charge.

[0207] Therefore, as shown in Figure 25, at a rotational position of 45°, the charge detection voltage signal V1 output from the first charge detection circuit decreases to approximately half of its peak value Vp, while the charge detection voltage signal V2 output from the second charge detection circuit increases to approximately half of its peak value Vp.

[0208] Next, Figure 23 shows the case where the rotating electrode 106 shown in Figure 20(C) is at a rotational position of 90°. The rectangular openings 1062 and 1063 of the rotating electrode 106 face the curved electrode pieces 1102 and 1104 of the second cage electrode 110, and the area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1102 and 1104 is maximized. As a result, the amount of induced dielectric charge on the curved electrode pieces 1102 and 1104 increases from approximately half of the maximum dielectric charge to the maximum dielectric charge. Therefore, as shown in Figure 25, at a rotational position of 90°, the charge detection voltage signal V2 output from the second charge detection circuit increases to its peak value Vp.

[0209] In contrast, the rectangular openings 1062 and 1063 of the rotating electrode 106 do not face the curved electrode pieces 1082 and 1084 of the first cage electrode 108. The area of ​​the rectangular openings 1062 and 1063 facing the curved electrode pieces 1082 and 1084 is minimized (determined as zero in this case), and the dielectric charge of the curved electrode pieces 1082 and 1084 decreases from approximately half of the maximum dielectric charge to zero. Therefore, as shown in Figure 25, at a rotational position of 90°, the charge detection voltage signal V1 output from the first charge detection circuit decreases to its minimum value of 0V.

[0210] Next, Figure 24 shows the case where the rotating electrode 106 shown in Figure 20(D) is positioned at a rotational position of 135°. The rectangular openings 1062 and 1063 of the rotating electrode 106 face a portion (approximately half) of the curved electrode pieces 1082 and 1084 of the first cage electrode 108 and a portion (approximately half) of the curved electrode pieces 1102 and 1104 of the second cage electrode 110. The induced dielectric charge of the curved electrode pieces 1082 and 1084 increases from zero to approximately half of the maximum dielectric charge, and the induced dielectric charge of the curved electrode pieces 1102 and 1104 decreases from the maximum dielectric charge to approximately half of the maximum dielectric charge.

[0211] Therefore, as shown in Figure 25, at a rotational position of 135°, the charge detection voltage signal V1 output from the first charge detection circuit increases to approximately half of its peak value Vp, while the charge detection voltage signal V2 output from the second charge detection circuit decreases to approximately half of its peak value Vp.

[0212] Then, when the rotating electrode 106 is rotated another 45° clockwise from the state shown in Figure 24, it returns to the same state as in Figure 21, and the states in Figures 21 to 24 are repeated sequentially thereafter. Note that when negatively charged smoke particles pass through the flue pipe 96, the polarity of the charge shown in the flue pipe 76, the first cage electrode 108, and the second cage electrode 110 shown in Figures 21 to 24 becomes reversed, and the charge detection voltage signals V1 and V2 shown in Figure 25 become signals with a negative peak value Vp.

[0213] (f6. Abnormality judgment section) Next, the abnormality detection unit will be described. The abnormality detection unit 84 uses charge detection voltage signals V1 and V2 based on the amount of charge detected by the charge detection unit 78 to determine whether the amount of charge detected by the charge detection unit 78 is the amount of charge of smoke generated by the abnormality. If it is determined that the detected amount of charge is the amount of charge of smoke generated by the abnormality, the unit detects an abnormality. The method of determination is arbitrary, and one example of such determination method is as follows.

[0214] When charged smoke particles pass through the flue pipe 96, the abnormality detection unit 84 receives charge detection voltage signals V1 and V2 that periodically change between a peak value Vp and zero, as shown in Figure 25. Based on the absolute value of the peak value Vp of the charge detection voltage signals V1 and V2, there is a determination method to determine whether the amount of charge detected by the charge detection unit 78 is the amount of charged smoke generated by an abnormality. For example, the absolute value of the peak value Vp is compared with a predetermined threshold, and if the absolute value of the peak value Vp is greater than or equal to the threshold, it is determined to be the amount of charged smoke generated by an abnormality, and if the absolute value of the peak value Vp is less than the threshold, it is determined not to be the amount of charged smoke generated by an abnormality.

[0215] Furthermore, the absolute value of the peak value Vp is used for determination because, when negatively charged smoke particles pass through the flue pipe 96, the peak value Vp will be negative, and when positively charged smoke particles pass through the flue pipe 96, the peak value Vp will be positive. This allows for a common threshold value for the peak value Vp, which will have different signs depending on the polarity of the charged smoke particles. Alternatively, separate threshold values ​​could be set for when negatively charged smoke particles pass through the flue pipe 96 and when positively charged smoke particles pass through the flue pipe 96, and the determination could be made based on the peak value Vp.

[0216] Furthermore, the peak value Vp used for the determination does not need to be just one; multiple peak values ​​Vp that differ over time (depending on the rotational position of the rotating electrode 106) may be used for the determination. When multiple peak values ​​Vp are used, for example, the absolute value of the average of the peak values ​​Vp is compared with a threshold for determination. When multiple peak values ​​Vp are used, only the peak value Vp of the charge detection voltage signal V1 or only the peak value Vp of the charge detection voltage signal V2 may be used, or both the peak values ​​Vp of the charge detection voltage signal V1 and V2 may be used. When determining using only one peak value Vp, the peak value Vp of either the charge detection voltage signal V1 or V2 will be used.

[0217] Furthermore, since the abnormality determination unit 84 receives two charge detection voltage signals, V1 and V2, in addition to comparing the absolute value of the peak value Vp with a predetermined threshold, it may also compare the peak value Vp of charge detection voltage signal V1 with the peak value Vp of charge detection voltage signal V2, and then determine whether the amount of charge detected by the charge detection unit 78 is the amount of charged charge of smoke generated by the abnormality.

[0218] When charged smoke particles pass through the flue pipe 96, a 90° phase difference is created between the charge detection voltage signals V1 and V2. However, there is almost no difference in the peak value Vp. Therefore, if the absolute value of the peak value Vp used for the determination is greater than or equal to the threshold, the peak value Vp of charge detection voltage signal V1 and the peak value Vp of charge detection voltage signal V2 are compared. For example, the error between the peak value Vp of charge detection voltage signal V1 and the peak value Vp of charge detection voltage signal V2 is calculated. If the error is within 10%, it is determined that the amount of charged smoke is due to an anomaly. If the error exceeds 10%, it is determined that the amount of charged smoke is not due to an anomaly, thereby improving the accuracy of the determination.

[0219] Furthermore, when comparing the peak value Vp of charge detection voltage signal V1 with the peak value Vp of charge detection voltage signal V2, it is not necessary to use only one peak value Vp; multiple peak values ​​Vp may be used. If multiple peak values ​​Vp are used, for example, the average value of the peak values ​​Vp may be used for comparison.

[0220] Another determination method involves determining whether the detected charge amount is the charge amount of smoke generated by an anomaly, based on the absolute value of the integral of the voltages of the charge detection voltage signals V1 and V2 over a predetermined period. For example, the absolute value of the integral is compared with a predetermined threshold, and if the absolute value of the integral is greater than or equal to the threshold, it is determined to be the charge amount of smoke generated by an anomaly; if the absolute value of the integral is less than the threshold, it is determined not to be the charge amount of smoke generated by an anomaly.

[0221] Here, the period for calculating the integral value is arbitrary, but for example, the starting point is the rising edge of the signal (when the charge detection voltage signal is at its minimum) or the falling edge (when the charge detection voltage signal reaches its peak value Vp), and the integral value is calculated for a predetermined period from the starting point, for example, one cycle or half a cycle. Furthermore, the detection of the starting point, such as the rising edge or falling edge, may be based on the voltage of the charge detection voltage signals V1 and V2, or on the rotational position of the rotating electrode 106.

[0222] Furthermore, the reason for using the absolute value of the integral for the determination is to unify the threshold when negatively charged smoke particles pass through the flue pipe 96 and when positively charged smoke particles pass through the flue pipe 96. If separate thresholds are set for when negatively charged smoke particles pass through the flue pipe 96 and when positively charged smoke particles pass through the flue pipe 96, the determination can be made using the integral value.

[0223] Furthermore, the integral value used for the determination may be the integral value of only the charge detection voltage signal V1 or only the charge detection voltage signal V2, or of course, the integral values ​​of both charge detection voltage signals V1 and V2 may be used. Also, when using multiple integral values ​​for the determination, for example, the average value of the integral values ​​may be used for the determination.

[0224] Furthermore, since the abnormality determination unit 84 receives two charge detection voltage signals, V1 and V2, in addition to comparing the absolute value of the integral value with a predetermined threshold, it may also compare the integral value of charge detection voltage signal V1 with the integral value of charge detection voltage signal V2, and then determine whether the amount of charge detected by the charge detection unit 78 is the amount of charged smoke generated by the abnormality.

[0225] When charged smoke particles pass through the flue pipe 96, a 90° phase difference is created between the charge detection voltage signals V1 and V2. However, there is almost no difference in the peak value Vp and the period of one cycle. Therefore, if the conditions for determining the integral value (starting point, period, etc.) are the same, there is almost no difference in the integral value. For this reason, if the absolute value of the integral value is greater than or equal to a threshold, the integral value of the charge detection voltage signal V1 and the integral value of the charge detection voltage signal V2 obtained under the same conditions are compared. For example, the error between the integral value of the charge detection voltage signal V1 and the integral value of the charge detection voltage signal V2 is calculated. If the error is within 10%, it is determined that the amount of charge is from smoke generated by an anomaly. If the error exceeds 10%, it is determined that the amount of charge is not from smoke generated by an anomaly.

[0226] Furthermore, the determination may be made based on both the peak value Vp and the integral value, or one or more other appropriate conditions related to the amount of charged charge, such as the time-dependent changes (degree of change, rate of change, amount of change) of the charge detection voltage signals V1 and V2, may be set to make the determination.

[0227] Furthermore, when positively charged smoke particles pass through the flue pipe 96, the peak value Vp and integral value are positive, and when negatively charged smoke particles pass through the flue pipe 96, the peak value Vp and integral value are negative. Therefore, the abnormality determination unit 84 can detect the charge polarity of the smoke (charged smoke particles) generated by the abnormality based on the polarity (positive or negative) of the peak value Vp or integral value, in either the determination method using the peak value Vp or the determination method using the integral value. If the peak value Vp or integral value is positive, the charge polarity of the smoke is set to positive, and if the peak value Vp or integral value is negative, the charge polarity of the smoke is set to negative.

[0228] Then, if the abnormality detection unit 84 determines that the amount of charge detected by the charge detection unit 78 is the amount of charge generated by the smoke due to the abnormality and detects an abnormality, it will transmit an abnormality detection signal containing information about the charge polarity of the smoke to the system control panels 50(50-1) and 50(50-2). The operation of the protective equipment after the system control panels 50(50-1) and 50(50-2) receive the abnormality detection signal and determine that an abnormality has occurred is basically the same as in the first embodiment, so the explanation will be omitted.

[0229] [f. Fourth embodiment of protective equipment] Next, a fourth embodiment of the protective equipment will be described. In this description, refer to Figure 26, which shows a front view (viewed from the front) of the fourth embodiment of the protective equipment, and Figure 27, which shows a top view (viewed from above) of the fourth embodiment of the protective equipment.

[0230] (f1. Configuration of protective equipment) First, the configuration of the protective equipment will be described. The fourth embodiment of the protective equipment is an embodiment in which the third embodiment, which is equipped with a smoke detection device 70 as an abnormality detection unit, is applied to an energy storage facility.

[0231] The energy storage facility 200 is equipped with multiple battery clusters 210. In this embodiment, as shown in Figure 27, 15 battery clusters 210 are arranged in three rows in the front-to-back direction and five rows in the left-to-right direction. To distinguish the sections in which the battery clusters 210 are installed, as shown in Figure 27, the five rows in the left-to-right direction are distinguished by the letters A to E, and the three rows in the front-to-back direction are distinguished by the numbers 1 to 3. Each section is designated by a combination of letter and number, for example, "A1," and each of sections A1 to E3 corresponds to one of the protected sections of the area to be protected.

[0232] Here, the energy storage facility 200, like the parking facility 10, is a three-dimensional space whose position can be determined by coordinates of mutually orthogonal X, Y, and Z axes. The Y axis is defined as the height direction (up and down direction), the X axis is defined as the left-right direction with the side of the opening / closing door 230 that allows access to the interior of the energy storage facility 200 being the right side, and the Z axis is defined as the front-back direction. Although the XYZ directions are also defined for the parking facility 10 and the smoke detection device 70, the XYZ directions defined for the parking facility 10 and the smoke detection device 70 do not necessarily coincide with the XYZ directions defined for the energy storage facility 200.

[0233] The battery cluster 210 houses, for example, a battery section 220 containing a high-voltage battery that houses multiple lithium-ion batteries. As shown in Figure 26, for example, it has a shelf structure divided into seven levels in the vertical direction, with battery sections 220 housed in five locations, excluding the bottom and top levels. The energy storage facility 200 also includes equipment for supplying power stored by the battery sections 220 housed in each of the battery clusters 210 to the outside, and equipment for charging the battery sections 220 to store power, but these are not shown in the figure.

[0234] Water supply pipes 20 are laid on the ceiling (upper) side of the energy storage facility 200, corresponding to the positions of each of the compartments A1 to E3 (protected compartments). Water spraying heads 14 and electrostatic spraying heads 26 are connected to the water supply pipes 20 via remote release valves 22. Furthermore, because the water spraying heads 14 and electrostatic spraying heads 26 are connected to the water supply pipes 20 via remote release valves 22, it is possible to spray fire extinguishing water for each of the compartments A1 to E3.

[0235] Furthermore, a high-voltage power supply unit (voltage supply unit) 36 is provided for each of the charged spraying heads 26, and the high-voltage power supply unit 36 ​​supplies a predetermined high voltage to the charged spraying heads 26 when the charged spraying heads 26 spray charged liquid particles.

[0236] Furthermore, smoke detection devices 70 are installed on the ceiling side of each of the sections A1 to E3 as abnormality detection units that detect abnormalities that generate smoke, such as fires caused by thermal runaway of lithium-ion batteries. Note that the smoke detection devices 70 may be installed on the battery cluster 210 side instead of on the ceiling side of the energy storage facility 200. For example, since the battery section 220 is not housed in the uppermost section of the battery cluster 210, the smoke detection devices 70 may be installed in the uppermost section of the battery cluster 210.

[0237] Furthermore, the remote release valve 22, the high-voltage power supply unit 36, and the smoke detection device 70 are connected to the system control panel 50 by a signal cable 54. Note that the water spraying head 14, the electrostatic spraying head 26, the high-voltage power supply unit 36, and the smoke detection device 70 are basically the same as those described in the previously mentioned embodiments, so a detailed explanation of them will be omitted.

[0238] In the fourth embodiment, a single system control panel 50 controls the monitoring of abnormalities in all sections A1 to E3, and determines that an abnormality has occurred when it receives an abnormality detection signal from the smoke detection device 70.

[0239] In addition, the system control panel 50 controls the spraying operations of the water spraying heads 14 and the charged spraying heads 26 in all compartments A1 to E3, and a pressurized water supply facility 15 is provided as a pressurized water supply facility for supplying fire extinguishing water to the water spraying heads 14 and the charged spraying heads 26.

[0240] The pressurized water supply facility 15 includes a motor 38, a pump 40, a fire extinguishing water source water tank 42, and a pump control panel 52. Also, the main water supply pipe 54 drawn out from the pump 40 is connected to the water supply pipe 20 connecting the water spraying heads 14 and the charged spraying heads 26.

[0241] (f2. Operation of protection equipment) Subsequently, the operation of the protection equipment will be described.

[0242] For example, when a thermal runaway occurs in the lithium-ion battery of the battery unit 220 housed in the battery cluster 210 installed in compartment A2, the smoke detection device 70 corresponding to compartment A2 senses the abnormality and transmits an abnormality detection signal to the system control panel 50. The system control panel 50 that receives the abnormality detection signal determines that there is an abnormality in compartment A2.

[0243] The system control panel 50 that determines an abnormality in compartment A2 transmits a pump start signal to the pump control panel 52 of the pressurized water supply facility 15. The pump control panel 52 that receives the pump start signal drives the motor 38 to start the operation of the pump 40, supplies pressurized fire extinguishing water from the fire extinguishing water source water tank 42 to the main water supply pipe 54, and drives the remote control valve 22 corresponding to compartment A2 to open, enabling the spraying of fire extinguishing water from the water spraying heads 14 and the spraying of charged liquid particles from the charged spraying heads 26.

[0244] Furthermore, the system control panel 50 determines the charge polarity of the charged liquid particles to be sprayed from the charged spraying head 26 based on information regarding the charge polarity of the smoke included in the abnormality detection signal, and transmits a control signal to the high-voltage power supply unit 36 ​​corresponding to section A2. In this case, since the smoke is generated by thermal runaway of the lithium-ion battery and the charge polarity of the smoke is negative, a predetermined voltage is applied to the water-side electrode section 2650 of the charged spraying head 26 so that the potential of the induction electrode section 2640 becomes negative, with the water-side electrode section 2650 of the charged spraying head 26 being the reference potential (earth potential, 0V), and positively charged liquid particles are sprayed from the charged spraying head 26.

[0245] Although the system control panel 50 is currently configured to perform the spraying operation on section A2, the sections to be sprayed are arbitrary. For example, the system control panel may also be configured to perform the spraying operation on sections A1, A3, and B2, which are adjacent to section A2, where an abnormality has been detected.

[0246] Furthermore, although the fourth embodiment performed all control with a single system control panel 50, similar to the first embodiment, the system control panel 50 (50-1) and 50 (50-2) may be used to perform fire monitoring control and spraying operation control of the water spraying head 14 and the charged spraying head 26, respectively. Also, although the protective equipment in the fourth embodiment does not include a water curtain forming head 18, it may include a water curtain forming head 18, similar to the first embodiment. In this case, the water curtain forming head 18 is installed to surround each section, and a water curtain is formed around the section deemed abnormal by the fire extinguishing water sprayed from the water curtain forming head 18.

[0247] [g. Fifth embodiment of protective equipment] Next, we will describe the fifth embodiment of the protective equipment.

[0248] (g1. Configuration of protective equipment) First, the configuration of the protective equipment will be explained. In this explanation, please refer to Figure 28, which shows a front view (viewed from the front) of the fifth embodiment of the protective equipment.

[0249] As shown in Figure 28, the fifth embodiment of the protective equipment is characterized by having an oxygen concentration detection unit 300 instead of the carbon dioxide sensor 28, carbon monoxide sensor 30, and hydrogen sensor 32 as the abnormality detection unit. Since the protective equipment is basically the same as the first embodiment except for the inclusion of the oxygen concentration detection unit 300, the same reference numerals are used for other components and their descriptions are omitted.

[0250] The oxygen concentration detection unit 300 is capable of detecting the rising oxygen concentration that occurs with the temperature rise leading to thermal runaway of the lithium-ion battery. Based on the detected oxygen concentration, it detects an abnormality, such as a fire caused by thermal runaway of the lithium-ion battery, and transmits an abnormality detection signal to the system control panels 50(50-1) and 50(50-2).

[0251] (g2. Changes in oxygen concentration during thermal runaway of lithium-ion batteries) Next, we will explain the change in oxygen concentration during thermal runaway of lithium-ion batteries. For this explanation, please refer to Figure 29, which shows the change in oxygen concentration over time as measured in a fire experiment involving lithium-ion batteries.

[0252] To briefly explain lithium-ion batteries and their thermal runaway again, a lithium-ion battery mainly consists of a positive electrode, a negative electrode, a separator separating the positive and negative electrodes, and an electrolyte that is filled into each of the positive and negative electrode sections. When a lithium-ion battery is charged or discharged, lithium ions move through the separator and into the electrolyte. Lithium ions on the positive electrode side move to the negative electrode side, creating a potential difference between the positive and negative electrodes, which charges the battery. Lithium ions on the negative electrode side move to the positive electrode side, creating a potential difference between the positive and negative electrodes, which discharges the battery.

[0253] "Thermal runaway of lithium-ion batteries" is a phenomenon in which a lithium-ion battery enters an abnormal heat state where it can reach high temperatures of 1000-1200°C due to certain causes, and in the worst case, it can ignite or explode. If it reaches the point of ignition or explosion, it can develop into a fierce fire. The causes of thermal runaway in lithium-ion batteries can be mainly divided into physical and electrical causes. In addition, when a lithium-ion battery experiences thermal runaway, it releases gases (white smoke) containing various combustion products such as hydrogen, carbon dioxide, and carbon monoxide.

[0254] The physical cause of thermal runaway in lithium-ion batteries is physical damage or deformation of any part of the lithium-ion battery. For example, the separator may be damaged by impact or pressure. When the separator is damaged, a short circuit occurs between the positive and negative electrodes. When a short circuit occurs, current flows rapidly to the negative electrode, causing it to overheat. The heated negative electrode then heats the positive electrode, triggering an exothermic reaction in the positive electrode. This triggers various heat-generating chemical reactions, such as reactions between the negative and positive electrodes and the electrolyte, decomposition of the electrolyte itself, and combustion reactions caused by sparks during the short circuit and oxygen released due to the collapse of the positive electrode's crystal structure. Ultimately, this leads to thermal runaway.

[0255] Furthermore, the electrical cause of thermal runaway in lithium-ion batteries is overcharging or over-discharging. When overcharged, the potential of the positive electrode relative to the negative electrode increases, causing the electrolyte to oxidize and decompose, resulting in heat generation on the positive electrode side. This heat gradually causes the separator to shrink and deform, short-circuiting the positive and negative electrodes. This triggers various heat-generating chemical reactions, similar to those caused by physical factors, and accelerates the shrinkage and deformation of the separator, ultimately leading to thermal runaway.

[0256] Furthermore, the inventors of this invention noted that while it can be difficult to experimentally measure hydrogen, carbon monoxide, nitric oxide, nitrogen dioxide, benzene, butadiene, and other combustion products generated during thermal runaway of lithium-ion batteries, it is relatively easy to experimentally measure carbon dioxide and oxygen. Therefore, they focused on oxygen among the combustion products generated during thermal runaway of lithium-ion batteries and measured the change in oxygen concentration during thermal runaway of lithium-ion batteries through fire experiments with lithium-ion batteries.

[0257] A fire experiment using a lithium-ion battery to measure changes in oxygen concentration was conducted by placing an 18650-type lithium-ion battery in a chamber of a predetermined size and heating the battery from below with a rod heater. The heating temperature of the rod heater, the temperature of the lithium-ion battery, and the oxygen concentration in the chamber were measured. The temperature of the lithium-ion battery was measured on the upper side (unheated surface) opposite the lower side heated by the rod heater, and the oxygen concentration in the chamber was measured by placing an oxygen concentration meter at a predetermined height away from the lithium-ion battery.

[0258] Figure 29 shows the time evolution of oxygen concentration obtained from the fire experiment, along with the time evolution of the heating temperature of the rod heater and the temperature of the lithium-ion battery. As shown by the dotted line in Figure 29, heating by the rod heater started after about 5 minutes and continued while gradually increasing the heating temperature until about 40 minutes had elapsed.

[0259] As shown by the solid line in Figure 29, the lithium-ion battery's temperature rises due to heating by the rod heater. When it reaches approximately 150°C, the safety valve activates and the temperature temporarily drops. However, after that, it can be confirmed that the temperature rapidly rises to approximately 550°C due to thermal runaway. Furthermore, as shown by the dashed line in Figure 29, the oxygen concentration gradually increases with the rise in temperature of the lithium-ion battery. At the time the safety valve activates, it has increased by approximately 1 vol% compared to before heating by the rod heater. After thermal runaway, it has increased by another approximately 1 vol% compared to the time the safety valve activates. This change in oxygen concentration confirms the release of oxygen from the lithium-ion battery in response to the temperature rise leading to thermal runaway. The release of oxygen from the lithium-ion battery is due to the exothermic reaction (thermal decomposition) of the positive electrode caused by the temperature rise, as mentioned above, which leads to the collapse of the crystal structure of the positive electrode.

[0260] Therefore, the oxygen concentration detection unit 300 pre-sets a threshold corresponding to the oxygen concentration at the timing when the safety valve activates (the timing immediately before thermal runaway occurs) as a condition for detecting thermal runaway of the lithium-ion battery. The detected oxygen concentration is compared with the threshold, and if an oxygen concentration equal to or exceeding the threshold is detected, a fire caused by thermal runaway of the lithium-ion battery is detected at an early stage.

[0261] In Figure 29, the oxygen concentration at the time the safety valve activates is approximately 21.8 vol%, and after thermal runaway, the oxygen concentration rises to approximately 22.8 vol%. However, this oxygen concentration is merely an example of data obtained through experimentation and is not limited to this value. The oxygen concentration threshold set in the oxygen concentration detection unit 300 can also be set to an appropriate value. Furthermore, the detection of fire caused by thermal runaway of the lithium-ion battery based on oxygen concentration by the oxygen concentration detection unit 300 is not limited to the oxygen concentration value. For example, fire caused by thermal runaway of the lithium-ion battery may be detected based on the amount or rate of change (amount of change / time) of change in oxygen concentration.

[0262] [h. Variations of the present invention] A modified example of the protective equipment according to the present invention will be described. The protective equipment of the present invention includes the following modifications in addition to the above-described embodiments.

[0263] (Battery storage facility) The above-described embodiment took, as an example, protective equipment for a parking facility where a battery-loaded vehicle is parked and an energy storage facility. However, the protected area targeted by the protective equipment is not limited to this. For example, it may be protective equipment for a battery storage facility that stores a battery unit (such as a battery pack) having a lithium-ion battery, and a protection section is formed corresponding to the storage location of the battery unit.

[0264] (Parking facility and energy storage facility) In the above-described embodiment, the parking facility has a total of six parking sections, three sections on each side of the central passage, and one vehicle entrance / exit is provided. However, the structure of the parking facility is not limited to this. Also, in the energy storage facility, the battery clusters are installed in 15 sections, and one opening / closing door is provided. However, the structure of the energy storage facility is not limited to this. The number and arrangement of the parking sections corresponding to the protection sections of the protected area and the sections where the battery clusters are installed are arbitrary, and the number and arrangement of the vehicle entrance / exit and the opening / closing doors are also arbitrary.

[0265] (Number and installation position of the charged liquid spraying head) <0​​​​​​​​​​​ In the above embodiment, high-voltage power supplies were individually provided for each electrostatic spraying head. However, a common high-voltage power supply may be provided for the entire protective facility or for each section where a predetermined number of parking spaces or battery clusters are installed, and individual high-voltage cables may be drawn from the common high-voltage power supply to the electrostatic spraying heads of each protective section.

[0268] (Battery in the battery section) In the above embodiment, the case where the battery is a lithium-ion battery is used as an example, but the type of battery is not limited to this. For example, the battery contained in the battery section may be an all-solid-state battery.

[0269] The structure of an all-solid-state battery is similar to that of a lithium-ion battery; the positive and negative electrodes are the same as those of a lithium-ion battery. However, unlike lithium-ion batteries which use an electrolyte, all-solid-state batteries do not. Nevertheless, even without an electrolyte, there is still a possibility of fire occurring due to an all-solid-state battery. A short-circuited all-solid-state battery can reach temperatures of around 1800°C in the event of thermal runaway, which is significantly higher than that of a lithium-ion battery. Therefore, the area where the battery section containing the all-solid-state battery is located should also be protected by protective equipment.

[0270] (spreading operation) In the above embodiment, we take the example of a case where the generated smoke has a negative charge polarity and the dispersed charged liquid particles have a positive charge polarity, but we are not limited to this. In addition, depending on the type of battery placed in the area to be protected, it is conceivable that smoke may be positively charged during combustion, smoke whose charge polarity changes over time, or a mixture of positively charged and negatively charged smoke may be present.

[0271] Therefore, if the smoke is positively charged, negatively charged liquid particles are sprayed. Also, if the charge polarity of the smoke changes over time, the charge polarity of the liquid particles is changed according to the change in the smoke's charge polarity before spraying. Furthermore, if positively charged and negatively charged smoke are present, the charge polarity of the liquid particles is changed periodically, for example, to alternately spray positively charged and negatively charged liquid particles. In addition, the voltage applied from the high-voltage power supply (voltage supply unit) to the charged spraying head in order to alternately spray positively charged and negatively charged liquid particles may be changed in an alternating current manner or in a pulsed manner.

[0272] (Protective equipment combining multiple embodiments) In the above embodiments, the first embodiment was used as the basic embodiment when the area to be protected is a parking facility. A second embodiment with an added drainage structure, a third embodiment equipped with a smoke detection device as an abnormality detection unit, and a fifth embodiment equipped with an oxygen concentration detection unit as an abnormality detection unit were discussed. However, any combination of these embodiments is permitted. For example, the second embodiment with an added drainage structure may be applied to the third or fifth embodiment. Alternatively, the third or fifth embodiment may be combined with the first embodiment to provide a smoke detection device and an oxygen concentration detection unit in addition to a hydrogen sensor, carbon dioxide sensor, and carbon monoxide sensor as an abnormality detection unit. Furthermore, in the fourth embodiment, the third embodiment equipped with a smoke detection device as an abnormality detection unit was applied to an energy storage facility when the area to be protected is an energy storage facility. However, embodiments of the first, second, and fifth embodiments may also be applied to an energy storage facility.

[0273] (Charge detection unit of smoke detection device) In the above embodiment, the charge detection unit of the smoke detection device had two charge detection signal outputs, but the charge detection signal output may be just one output.

[0274] (Smoke detection device abnormality detection unit) In the above embodiment, the abnormality determination unit of the smoke detection device detected an abnormality by determining whether the detected charge amount is the charge amount of smoke generated by the abnormality. However, it is not limited to this, and it may also detect an abnormality by determining whether the detected charge polarity is the charge polarity of smoke generated by the abnormality.

[0275] For example, experiments conducted by the inventors of this invention have confirmed that the charge polarity of the white smoke produced when a fire (abnormality) occurs due to thermal runaway of a lithium-ion battery is negative. Therefore, when the abnormality determination unit of the smoke detection device detects negative polarity, there is a high probability that smoke caused by a fire due to thermal runaway of a lithium-ion battery has been detected. Thus, it is possible to determine that this detected negative polarity is the charge polarity of smoke produced by a fire (abnormality) caused by thermal runaway of a lithium-ion battery, and to detect a fire (abnormality) caused by thermal runaway of a lithium-ion battery.

[0276] As an example, we have discussed a fire caused by thermal runaway of a lithium-ion battery, but even in the case of other abnormalities that generate smoke, if the type of battery in the battery section is fixed and the charge polarity of the smoke generated by the abnormality has been investigated in advance through experiments, the abnormality detection unit of the smoke detection device can similarly determine whether the detected charge polarity is the charge polarity of the smoke generated by the abnormality and detect the abnormality.

[0277] (Detection of fires caused by thermal runaway in lithium-ion batteries using an oxygen concentration detection unit) In the above embodiment, an oxygen concentration detection unit was used to detect a fire caused by thermal runaway of the lithium-ion battery based on the oxygen concentration. However, in order to consider the temperature rise in addition to the rise in oxygen concentration leading up to thermal runaway when detecting a fire caused by thermal runaway of a lithium-ion battery, a temperature detection unit may be provided as an abnormality detection unit, and the fire caused by thermal runaway of the lithium-ion battery may be detected based on the oxygen concentration and temperature.

[0278] (others) Furthermore, the present invention includes appropriate modifications that do not impair its purpose and advantages, and is not limited by the numerical values ​​shown in the above embodiments. [Explanation of symbols]

[0279] 10: Parking facilities 11: Vehicle entrance / exit 12,12(12-1)~12(12-6): Parking spaces 14: Water spray head 15: Pressurized water supply equipment 15(15-1): First Pressurized Water Supply Equipment 15(15-2): Second Pressurized Water Supply Equipment 16,20: Water supply piping 18: Water film forming head 22: Remote-controlled valve 24: Manual selector valve 26: Electrostatic dispersal head 2610: Body 2620: Spray nozzle section 2630: Electrode holding part 2640: Induction electrode part 2642: Cable connection part 2650: Water side electrode part 2652: Electrode connection part 2660: Pipe connection 2670:Scatter axis 28: Carbon dioxide sensor 30: Carbon monoxide sensor 32: Hydrogen sensor 34, 34(34-1), 34(34-2), 34(34-4): Battery-powered vehicles 35: High-voltage cable 3510: Voltage application cable 3520: Earth cable 36: High-voltage power supply 3610: High-voltage variable circuit 3620: Polarity Reversal Circuit 3630: Current limiting resistor 38,38(38-1),38(38-2): Motor 40,40(40-1),40(40-2): Pump 42,42(42-1),42(42-2): Fire water source water tank 44, 54: Main water supply pipe 46(46-1): Simultaneous opening valve 48(48-1): Starter electric valve 50, 50(50-1), 50(50-2): System control panel 52, 52(52-1), 52(52-2): Pump control panel 55: Signal cable 56: Drain 58: Drain pipe 60: Wastewater recovery tank 62: Sewer inlet piping 70: Smoke detection device 72: Main unit of the device 74: Rotary drive unit 76: Connecting pipe 78: Charge detection unit 79: Circuit storage section 80:Suction part 8010: Inlet 82: Operation Control Unit 84: Abnormality determination section 86: Rotation detector 8610: Slit disk 8612: Photo Interrupter 88: Motor 90: Reduction section 9010, 9012, 9014: Gear 92,94: Entrance / exit 9210, 9410: Internal piping section 96: Flue pipe 98,100: Flange member 102,104: Bearings 105: Marker 106: Rotating electrode 1060: Cylindrical surface 1062,1063: Rectangular opening 1064: Internal passage 1066: Flange section 1068: Screw hole 1069: Grounding ring section 108: First cage electrode 1080: Circular section 1082,1084: Curved electrode piece 110: Second cage electrode 1100: Circular section 1102, 1104: Curved electrode piece 112,114: Insulating ring 116: External electrode 118, 119, 120, 121: Electrode pins 122,124: Operational amplifier 125: Circuit board 126,128: Feedback resistors 130: Oscilloscope 132,134: Sine waveform 200: Energy storage facilities 210: Battery cluster 220: Battery section 230: Opening and closing doors 300: Oxygen concentration detection unit

Claims

1. A protective device for protecting a protected area in which a battery unit having a predetermined battery is located, An abnormality detection unit that detects abnormalities, including fires, caused by the battery unit located in the protected area, A charged spraying head capable of spraying charged liquid particles, which are liquid particles of fire extinguishing liquid that have been charged, onto the area to be protected, A voltage supply unit that supplies a predetermined high voltage to the charged spraying head when the charged spraying head sprays the charged liquid particles, When the abnormality detection unit detects the abnormality, a control unit controls the spraying operation to spray the charged liquid particles from the charged spraying head, Equipped with, The protective device is characterized in that the control unit controls the spraying operation so as to spray charged liquid particles from the charged spraying head that have the opposite polarity to the charge polarity of a predetermined smoke generated by a fire caused by the battery unit.

2. The protective equipment according to claim 1, The protective equipment is characterized in that the control unit controls the spraying operation so that the charge polarity of the charged liquid particles sprayed from the charged spraying head is switched at a predetermined timing, and positively charged liquid particles and negatively charged liquid particles are sprayed alternately from the charged spraying head.

3. The protective equipment according to claim 1, The predetermined battery in the battery section is a lithium-ion battery. The abnormality detection unit detects a fire caused by thermal runaway of the lithium-ion battery as a fire originating from the battery unit, The protective equipment is characterized in that the control unit controls the spraying operation so as to spray positively charged liquid particles from the charged spraying head, which have the opposite polarity to the negatively charged smoke generated by a fire caused by thermal runaway of the lithium-ion battery.

4. The protective equipment according to claim 3, The abnormality detection unit includes a hydrogen sensor, a carbon dioxide sensor, and a carbon monoxide sensor. The protective system is characterized in that the control unit determines that the abnormality detection unit has detected a fire caused by thermal runaway of the lithium-ion battery when all of the detection results from the hydrogen sensor, the carbon dioxide sensor, and the carbon monoxide sensor satisfy predetermined detection conditions.

5. The protective equipment according to claim 3, The abnormality detection unit includes an oxygen concentration detection unit that detects the oxygen concentration, The protective device is characterized in that the oxygen concentration detection unit detects a fire caused by thermal runaway of the lithium-ion battery based on the detected oxygen concentration.

6. The protective equipment according to claim 1, The abnormality detection unit includes a smoke detection device capable of detecting the amount of electric charge of smoke generated by the abnormality. The smoke detection device is a protective device characterized by determining whether the detected charge amount is the charge amount of smoke generated by the abnormality, and detecting the abnormality if it is determined to be the charge amount of smoke generated by the abnormality.

7. The protective equipment according to claim 6, The smoke detection device is also capable of detecting the charge polarity of smoke generated by an abnormality, and when an abnormality is detected, it transmits information regarding the detected charge polarity of the smoke to the control unit. The protective equipment is characterized in that the control unit controls the dispersal operation so that the charge polarity of the charged liquid particles is the opposite polarity of the charge polarity of the smoke detected by the smoke detection device.

8. The protective equipment according to claim 1, The abnormality detection unit includes a smoke detection device capable of detecting the charge polarity of smoke generated by the abnormality. The smoke detection device is a protective device characterized by determining whether the detected charge polarity is the charge polarity of smoke generated by the abnormality, and detecting the abnormality if it is determined to be the charge polarity of smoke generated by the abnormality.

9. The protective equipment according to claim 8, When the smoke detection device detects an abnormality, it transmits information regarding the charge polarity of the detected smoke to the control unit. The protective equipment is characterized in that the control unit controls the dispersal operation so that the charge polarity of the charged liquid particles is the opposite polarity of the charge polarity of the smoke detected by the smoke detection device.

10. The protective equipment according to claim 1, A protective device characterized by having a drainage structure for collecting the fire extinguishing liquid sprayed on the protected area into a wastewater collection tank.

11. The protective equipment according to claim 1, The area to be protected is divided into multiple protective compartments corresponding to the positions where the battery unit is located. For each of the aforementioned protective compartments, The abnormality detection unit, The aforementioned electrostatic dispersal head, A fire extinguishing liquid spraying head for spraying the fire extinguishing liquid onto the battery section of the protected area, A water curtain forming head that sprays the fire extinguishing liquid from the ceiling side of the protected compartment to form a water curtain surrounding the protected compartment to which it belongs, A system was established, The protective equipment is characterized in that, when any of the abnormality detection units detect an abnormality, the control unit controls a spraying operation to form a water curtain by spraying the fire extinguishing liquid from the fire extinguishing liquid spraying head and the fire extinguishing liquid from the water curtain forming head, in addition to the spraying operation of spraying the charged liquid particles from the charged spraying head for a predetermined protected area including the protected area where the abnormality was detected.

12. The protective equipment according to claim 11, A protective device characterized in that a manual operation unit is provided at a predetermined position corresponding to the area to be protected, for operating the start and stop of water discharge from the water curtain forming heads, which are provided corresponding to each protected section.

13. The protective equipment according to claim 1, The protective equipment is characterized in that the area to be protected is a parking facility for a mobile body on which the battery unit is loaded, and is divided into a plurality of protective sections corresponding to the parking locations of the mobile body.

14. The protective equipment according to claim 1, The protective equipment is characterized in that the area to be protected is a battery storage facility for storing the battery unit, and is divided into a plurality of protective compartments corresponding to the storage location of the battery unit.

15. The protective equipment according to claim 1, The protective equipment is characterized in that the area to be protected is an energy storage facility that stores electricity using the battery unit, and is divided into a plurality of protective compartments corresponding to the location where the battery unit is installed.

Images