Secondary battery fire suppressant, secondary battery fire suppression member, and secondary battery

Abstract

Embodiments of the present invention provide a fire suppressant, a fire suppression member, and a secondary battery containing the first substance, comprising one or more first substances having a decomposition initiation temperature and a second substance mixed with the first substances to bind the first substances, wherein the first substances decompose when they reach the decomposition initiation temperature, thereby decomposing flammable organic compounds and rendering them non-flammable.

Description

Technical Field

[0001] The present invention relates to a secondary battery fire suppressant, a secondary battery fire suppression member, and a secondary battery, and more particularly, to a secondary battery fire suppressant, a secondary battery fire suppression member, and a secondary battery that can effectively suppress a fire in a secondary battery.

Background Art

[0002] A secondary battery having a high degree of electrical energy integration can be vulnerable to impact.

[0003] A secondary battery instantaneously releases the high energy accumulated due to internal defects or external impacts, induces thermal runaway within a short time, and is accompanied by a fire, making it very difficult to deal with accidents.

[0004] When a fire occurs in a secondary battery, the normal countermeasure is to try to extinguish it.

[0005] Lithium present in a secondary battery liquefies at its melting point of 108.5°C and rapidly vaporizes at 500°C or higher. When a secondary battery undergoes thermal runaway, a white gas is generated, and the main component of this white gas is vaporized lithium. As lithium vaporizes, the pressure inside the battery cell increases and it completely vaporizes at 1337°C. If the battery cell ruptures due to the inability to withstand such an increase in pressure, the lithium gas rapidly reacts with oxygen, generating flame and heat, and causing thermal runaway.

[0006] Therefore, as a method for dealing with a fire in a secondary battery, it is not appropriate to rely on extinguishing the fire after it has occurred as in the prior art. That is, a new technology that can cut off the thermal runaway of a secondary battery beforehand or suppress the fire quickly even if thermal runaway occurs is required.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

[0008] The objective of this invention is to provide a fire suppressant and a fire suppression member containing the same that can effectively suppress fires in secondary batteries, in order to solve the technical problems that this invention aims to achieve. The technical problems that this invention aims to solve are not limited to those mentioned above, and other technical problems not mentioned can be clearly understood by a person skilled in the art to which this invention belongs from the following description. [Means for solving the problem]

[0009] A fire suppressant according to one embodiment of the present invention comprises one or more first substances having a decomposition initiation temperature, and a second substance that is mixed with the first substances to bind them, wherein the first substances decompose when they reach the decomposition initiation temperature, thereby decomposing flammable organic compounds and rendering them non-flammable.

[0010] The first substance may be a fire extinguishing agent, and the second substance may be an organic binder.

[0011] The fire-extinguishing substance comprises two or more fire-extinguishing substances, each having two or more decomposition initiation temperatures, and can decompose stepwise to render the flammable organic compound non-flammable.

[0012] The first substance may contain one or more of the following: carbonates, chlorides, hydroxides, and phosphates.

[0013] The carbonate may contain one or more of the following: sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), potassium carbonate (K2CO3), potassium bicarbonate (KHCO3), ammonium carbonate ((NH4)2CO3), and ammonium bicarbonate (NH4HCO3).

[0014] The chloride may contain one or more of the following: ammonium chloride (NH4Cl), potassium chloride (KCl), aluminum chloride (AlCl3), and sodium chloride (NaCl).

[0015] The hydroxide may include one or more of the following: sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), and magnesium hydroxide (Mg(OH)2).

[0016] The phosphate may contain one or more of ammonium phosphate ((NH4)3PO4), sodium phosphate (Na3PO4), and potassium phosphate (K3PO4).

[0017] The fire suppressant may be provided in one or more phases from among paste, liquid, and gaseous.

[0018] The second substance may include one or more organic adhesives and elastomers.

[0019] A fire suppression member according to another embodiment of the present invention comprises a pair of fiber members, one or more fire extinguishing substances provided between the pair of fiber members and having a decomposition initiation temperature upon reaching the decomposition initiation temperature, which decomposes to decompose a flammable organic compound, and a fire suppressant comprising an organic binder mixed with the fire extinguishing substances, thereby capable of decomposing a flammable organic compound.

[0020] A secondary battery according to yet another embodiment of the present invention comprises one or more fire-extinguishing substances having a decomposition onset temperature; and an organic binder to be mixed with the fire-extinguishing substances; wherein the fire-extinguishing substances may include a fire suppressant that decomposes upon reaching the decomposition onset temperature, thereby rendering flammable organic compounds non-flammable. [Effects of the Invention]

[0021] According to an embodiment of the present invention, it is possible to provide a fire suppressant, a fire suppression member, and a secondary battery including the same that can effectively suppress a fire in a secondary battery.

Brief Description of Drawings

[0022] [Figure 1] It is a conceptual diagram of a secondary battery fire suppressant according to an embodiment of the present invention. [Figure 2] It is a Fourier transform infrared analysis (FRIT) experimental graph for carbon monoxide and acetylene gas generated during thermal runaway of a secondary battery cell according to an embodiment of the present invention. [Figure 3] It is a photographic view showing a paste image of a secondary battery fire suppressant according to an example of the present invention. [Figure 4] It is a photographic view showing a fire suppression member of a secondary battery according to an example of the present invention. [Figure 5] It is an exemplary diagram for explaining an example of use of a secondary battery fire suppression member according to an example of the present invention.

Modes for Carrying Out the Invention

[0023] Hereinafter, the present invention will be described with reference to the attached drawings. However, the present invention can be embodied in various different forms, and thus is not limited to the embodiments described herein. And, in order to clearly explain the present invention in the drawings, parts not related to the explanation are omitted, and similar reference numerals are given to similar parts throughout the specification.

[0024] In describing the present invention, when it is determined that a specific description of a known technique related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof is omitted. And, the terms described below are terms defined in consideration of the functions in the present invention, and these can be changed depending on the intention or convention of the user, operator, etc. Therefore, the definition thereof must be given based on the content throughout this specification.

[0025] The technical concept of the present invention is determined by the claims, and the following embodiments are merely means of efficiently explaining the technical concept of the present invention to a person ordinary skill in the art to which the present invention pertains.

[0026] The terms used herein are used solely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “includes” or “having” are intended to specify the existence of features, figures, stages, operations, components, parts, or combinations thereof described in the specification, and should not be understood to preemptively exclude the existence or possibility of adding one or more other features, figures, stages, operations, components, parts, or combinations thereof.

[0027] Embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0028] Figure 1 is a schematic example of a secondary battery fire suppressant according to one embodiment of the present invention.

[0029] As shown in Figure 1, the secondary battery fire suppressant 100 is for suppressing fires in secondary batteries and may contain a first substance and a second substance. The first substance is a substance that has a decomposition initiation temperature and is fire-extinguishing, and in describing embodiments of the present invention below, it will be referred to as one of a fire-extinguishing formulation, a fire-extinguishing substance, and a fire-extinguishing powder. The second substance is a substance that is mixed with the first substance to bind the first substance, and in describing embodiments of the present invention below, it may be referred to as an organic binder 120.

[0030] A secondary battery fire suppressant 100 according to one embodiment of the present invention may include a fire-extinguishing substance 110 and an organic binder 120. The fire-extinguishing substance 110 means a fire-extinguishing composition that can function in liquid, gaseous, solid, or phase-separated states, and may be described below as fire-extinguishing substance 110 or fire-extinguishing powder 110, but this is for the purpose of describing a representative example and is not to be interpreted as being limited to a specific state or form.

[0031] The fire-extinguishing substance 110 can induce suffocation against fire by blocking contact with oxygen, and may be a compound of a carbonate ion, which is reactive with lithium, and a monovalent or divalent cation.

[0032] The fire-extinguishing substance 110 may be an inorganic salt, for example, an inorganic salt powder. The inorganic salt preparation may contain alkali metals, alkaline earth metals, and ammonium-based substances on the periodic table that have strong oxygen radical suction capabilities.

[0033] Alkali metal compounds may include one or more of the following: sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), potassium carbonate (K2CO3), and potassium bicarbonate (KHCO3).

[0034] Furthermore, the alkaline earth metals may include one or more of the following: magnesium bicarbonate (Mg(HCO3)2), magnesium carbonate (MgCO3), calcium carbonate (CaCO3), and calcium bicarbonate (Ca(HCO3)2).

[0035] Furthermore, the ammonium-based substance may include one or more of the following: ammonium carbonate ((NH4)2CO3) and ammonium bicarbonate (NH4HCO3).

[0036] The fire-extinguishing substance 110 may specifically be an inorganic carbonate.

[0037] When carbonates are decomposed by heat, reactive decomposition gases and cationic metal ions may be automatically released.

[0038] If a secondary battery is damaged due to internal or external factors such as damage to the separator membrane or the application of external pressure, the resistance will increase due to a short circuit between the positive and negative electrodes caused by the damage to the separator membrane. This generates resistance heat, and in parallel with a rapid exothermic reaction that induces thermal decomposition of the electrolyte material and the release of flammable and toxic gases, the temperature and internal pressure of the secondary battery will rise rapidly as shown in Table 1 below.

[0039] [Table 1]

[0040] Here, when a carbonate contained in the fire suppressant for secondary batteries according to the embodiment of the present invention, for example, a carbonate contained in a lithium battery, is exposed to such heat, it can react and decompose as shown in the following reaction equation.

[0041] While this phenomenon is partly due to the influence of organic matter inside the battery cell, the most significant factor is that, as shown in chemical formulas 1 and 2 below, lithium ions either gain electrons and become lithium metal, which then vaporizes into itself, or they combine with nitrogen in the air to form lithium nitride.

[0042] [ka]

[0043] [ka]

[0044] Then, as shown in chemical formulas 3 to 5 below, lithium and lithium nitride rapidly react with water vapor and oxygen, burning as lithium peroxide or lithium oxide while generating a lot of heat.

[0045] [ka]

[0046] [ka]

[0047] [ka]

[0048] On the other hand, in such a high-temperature environment, the carbonate according to the embodiment of the present invention may decompose, generating reactive decomposition gases and cationic metal ions.

[0049] The reactive decomposition gas produced can deflammate the flammable gas (lithium gas) ejected from secondary batteries. The reactive decomposition gas ejected when carbonates are decomposed by heat can be carbon dioxide (CO2).

[0050] Furthermore, cationic metal ions can absorb radicals generated from electrical sparks or fires, thereby interrupting the chain reaction of combustion.

[0051] As shown in chemical formulas 6 and 7 below, if a fire occurs in a secondary battery, the heat generated can decompose the carbonate and release carbon dioxide. Then, the vaporized lithium can be converted into carbonate by reacting with carbon dioxide and oxygen, thereby becoming non-flammable.

[0052] Thus, as carbonates decompose, they release carbon dioxide, and the suffocating effect of the carbon dioxide blocks the access of oxygen, which can effectively mitigate or extinguish combustion caused by secondary battery fires.

[0053] [ka]

[0054] [ka]

[0055] On the other hand, in situations where the temperature and internal pressure of a secondary battery rise rapidly due to various causes, sparks generated inside the secondary battery can induce ignition by generating radical ions.

[0056] When the carbonate contained in the fire-extinguishing substance 110 according to the embodiment of the present invention is decomposed by heat, cationic metal ions (for example, alkali metals or alkaline earth metals) may be generated.

[0057] Here, radical ions can be absorbed by cationic metal ions. Through this, the generation of sparks in the secondary battery can be suppressed, and ignition of the secondary battery can be blocked. In other words, such a subcatalytic effect can suppress the chain reaction of combustion in the secondary battery. Therefore, it is possible to prevent fires in secondary batteries by including the secondary battery fire suppressant according to the embodiment of the present invention, and the spread of any fires that do occur can be suppressed.

[0058] Here, the carbonates that may be included in the fire extinguishing substance 110 according to the embodiment of the present invention may be one or more of the following: sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), potassium carbonate (K2CO3), potassium bicarbonate (KHCO3), magnesium bicarbonate (Mg(HCO3)2), magnesium carbonate (MgCO3), calcium carbonate (CaCO3), calcium bicarbonate (Ca(HCO3)2), ammonium carbonate ((NH4)2CO3), and ammonium bicarbonate (NH4HCO3). Here, depending on the decomposition onset temperature of each carbonate as shown in Table 2 below, only one carbonate may be included, or two or more of these may be included in a combination.

[0059] [Table 2]

[0060] Here, the decomposition initiation temperature may be the temperature at which the decomposition of the carbonate begins. As shown in Table 2, each carbonate may have its own unique decomposition initiation temperature. The carbonate may be selected according to user requirements, such as the temperature at which the required carbonate should decompose and exhibit its fire suppression function, or for weight adjustment due to differences in reactivity with organic substances that may be contained in secondary batteries or molecular weight, and may be included in secondary battery fire suppressants.

[0061] In addition, as shown in Table 3 below, two or more carbonates may be included in the secondary battery fire suppressant. Such formulations are intended to achieve gradual fire suppression and have the effect of further guaranteeing the fire suppression effect. Here, the fire suppression function is achieved when the carbonates listed in Table 2 begin to decompose at the decomposition initiation temperature at which they decompose. The secondary battery fire suppressant according to the embodiment of the present invention may contain 50% or more of carbonates having a decomposition initiation temperature closest to the fire hazard temperature. Alternatively, it may contain 50% or more of carbonates having a decomposition initiation temperature that is the same as or lower than the hazard temperature and closest to the fire hazard temperature.

[0062] [Table 3]

[0063] Here, a decomposition initiation temperature at which the decomposition of carbonate begins can be selected to suppress fire. Such a selection can be based on the settings of the lithium-ion secondary battery producer or the producer of the product in which the lithium-ion secondary battery is installed. The temperature considered a hazardous temperature may differ depending on the production and usage environment of the secondary battery user. For example, a temperature of 60°C or higher may be considered a fire hazard for lithium-ion secondary batteries, or it may be considered that a fire has occurred. Depending on the situation, a temperature of 100°C or higher may be considered a fire hazard for lithium-ion secondary batteries, or it may be considered that a fire has occurred. Therefore, a specific temperature range considering the operating temperature range of the secondary battery may be considered a hazardous temperature range, and carbonate may be included so that its decomposition initiation temperature falls within that hazardous temperature range, or carbonate with a decomposition initiation temperature lower or higher than that hazardous temperature may be additionally selected and blended.

[0064] For example, as shown in Table 3, if the user's perceived hazardous temperature range is 60°C or higher, the carbonate may contain 55% by weight ammonium carbonate, 20% by weight potassium bicarbonate, and 5% by weight magnesium carbonate. The carbonate can be formed from these proportions. In this case, ammonium carbonate, which accounts for the largest weight percentage, may decompose first at the hazardous temperature of 60°C, allowing the primary fire extinguishing process (first fire extinguishing process) to proceed. However, if the fire is not extinguished by the primary fire extinguishing process and the temperature rises further to 100-120°C, potassium bicarbonate, which accounts for the next largest weight percentage, may decompose, allowing the secondary fire extinguishing process (second fire extinguishing process) to proceed. Nevertheless, if the temperature continues to rise and reaches the decomposition start temperature of magnesium carbonate, the tertiary fire extinguishing process (third fire extinguishing process) by magnesium carbonate may proceed. In other words, as the temperature rises, the fire extinguishing process can proceed in stages.

[0065] If the carbonate consists solely of substances with decomposition initiation temperatures within the hazardous temperature range, all substances will decompose at the relevant decomposition initiation temperature, and the fire extinguishing process will be carried out. However, if complete extinguishing is not achieved despite this process, it will not be possible to prevent a rapid rise in the fire temperature, and the occurrence of thermal runaway will not be delayed. This would not provide the vehicle driver with enough time to evacuate the vehicle.

[0066] However, as in the embodiment of the present invention, when two or more carbonates are blended, and the carbonates are not included in the hazardous temperature range, and the carbonates have a decomposition onset temperature that is the same as or lower than the lower limit of the hazardous temperature range, and the fire extinguishing process is carried out in stages, a rapid rise in fire temperature can be prevented, and the occurrence of thermal runaway can be delayed. This has the effect of providing time for the vehicle driver to evacuate.

[0067] Rechargeable batteries contain many types of organic compounds as the positive electrode, negative electrode, and electrolyte. A characteristic phenomenon of rechargeable battery fires is thermal runaway, where high-temperature flammable gases are ejected from the cells inside the battery, combine with oxygen inside and outside the pack, and cause an electrical short circuit or ignition due to high temperature. This thermal runaway and flame generation can generate toxic substances during this process.

[0068] Table 4 below shows the main gases generated during thermal runaway in an example secondary battery.

[0069] [Table 4]

[0070] Figure 2 is a graph for investigating the gases generated during thermal runaway and fire in a secondary battery containing a fire suppressant according to one embodiment of the present invention.

[0071] Fire suppressants can be included in secondary batteries in various forms. Figure 2 shows Fourier transform infrared analysis (FRIT) experimental graphs for hydrogen chloride and hydrogen fluoride gases generated during thermal runaway and fire in secondary batteries, when a component impregnated with a secondary battery fire suppressant according to an embodiment of the present invention is attached ('CO ppm component' and 'C2H 6 ppm component') and when it is not attached ('CO ppm' and 'C2H 6 ppm').

[0072] As shown in Figure 2, it can be confirmed that a secondary battery containing the secondary battery fire suppressant 100 effectively suppresses carbon monoxide (CO) and acetylene (C2H6), which are flammable gases generated during a secondary battery fire, compared to a secondary battery without the suppressant. Thus, the secondary battery fire suppressant 100 according to one embodiment of the present invention can effectively suppress or neutralize thermal runaway and fires generated during a secondary battery fire.

[0073] Such neutralization can be explained by adsorption and conversion reactions. That is, a secondary battery fire suppressant may be a compound comprising one (1) or two (2) or more carbonate ions, chloride ions, hydroxide ions, and phosphate ions that undergo adsorption and conversion reactions against fires that occur when a secondary battery experiences thermal runaway, and one (1) or two (2) or more monovalent, divalent, and trivalent cations.

[0074] A fire suppressant for a secondary battery according to one embodiment of the present invention may be provided in one (1)1 or two (2) or more of the following states: paste, liquid, or gas. The fire suppressant for a secondary battery provided in this manner may be located in a separately partitioned area inside the secondary battery. Alternatively, the fire suppressant for a secondary battery may be located inside the secondary battery without being located in a separately partitioned area, but impregnated with a sheet or the like. In this case, the sheet impregnated with the fire suppressant for a secondary battery may be located on the outer surface, inner surface, or inner surface as an intermediate layer of the pouch forming each cell of the secondary battery, and may be included in the entire surface of the pouch, or in a part of the surface of the pouch.

[0075] Furthermore, the sheet impregnated with the secondary battery fire suppressant may be applied to or attached to the inner surface of the battery pack case housing the secondary battery, or sprayed from the inside or outside of the battery pack.

[0076] When the fire suppressant in a secondary battery decomposes due to thermal runaway in a secondary battery according to an embodiment of the present invention, reactive decomposition gases and cationic metal ions may be generated and ejected.

[0077] The reactive decomposition gas that is ejected can detoxify toxic gases ejected from secondary batteries. The reactive decomposition gas ejected when a secondary battery fire suppressant according to an embodiment of the present invention, which contains one (1) or two (2) or more of carbonates, chlorides, hydrates, or phosphates, is decomposed by heat may contain one (1) or two (2) or more of carbon dioxide (CO2), chlorine gas, hydroxide radicals, or phosphoric acid gas.

[0078] Furthermore, cationic metal ions can absorb radicals generated from electrical sparks or fires, thereby interrupting the chain reaction of combustion reactions and suppressing the chain reaction of fires.

[0079] The carbonate contained in the fire suppressant for secondary batteries according to the embodiments of the present invention may be a fire suppressant for secondary batteries containing one or more of the following: sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), potassium carbonate (K2CO3), potassium bicarbonate (KHCO3), ammonium carbonate ((NH4)2CO3), and ammonium bicarbonate (NH4HCO3).

[0080] The chlorides that may be included in the fire suppressant for secondary batteries according to the embodiments of the present invention may be fire suppressants containing one (1) or two (2) or more of the following: ammonium chloride (NH4Cl), potassium chloride (KCl), aluminum chloride (AlCl3), and sodium chloride (NaCl).

[0081] The hydroxides that may be included in the fire suppressant for secondary batteries according to the embodiments of the present invention may be fire suppressants containing one (1) or two (2) or more of the following: sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), and magnesium hydroxide (Mg(OH)2).

[0082] The phosphates that may be included in the fire suppressant for secondary batteries according to the embodiments of the present invention may be fire suppressants containing one (1) or two (2) or more of ammonium phosphate ((NH4)3PO4), sodium phosphate (Na3PO4), and potassium phosphate (K3PO4).

[0083] Examples of carbonate substances used in secondary battery fire suppressants can be implemented as shown in Table 5.

[0084] [Table 5]

[0085] Examples of chloride-based formulations for secondary battery fire suppressants can be implemented as shown in Table 6.

[0086] [Table 6]

[0087] Examples of hydroxide formulations among secondary battery fire suppressants can be implemented as shown in Table 7.

[0088] [Table 7]

[0089] Examples of phosphate formulations among secondary battery fire suppressants can be implemented as shown in Table 8.

[0090] [Table 8]

[0091] Here, considering the presence of flammable gases, a carbonate may be selected for inclusion in the secondary battery fire suppressant according to the embodiment of the present invention. The secondary battery containing the secondary battery fire suppressant according to the embodiment of the present invention may be selected by the secondary battery manufacturer or user, taking into consideration the operating environment (such as operating temperature) and the type of gas deemed to be a dangerous flammable gas.

[0092] In other words, depending on the usage and operating environment, the flammable gas that can be judged as potentially causing a dangerous fire when using a secondary battery may differ. For example, CO can be judged as a gas that can cause a dangerous fire in a secondary battery. In this case, depending on the flammable gas that can cause a dangerous fire, a portion of the carbonate may be appropriately selected and used alone or in combination with other carbonates.

[0093] For example, if the flammable gas that can induce a dangerous fire is carbon monoxide (CO), the mixture may contain 55% by weight of sodium carbonate, 20% by weight of sodium bicarbonate, and 5% by weight of magnesium carbonate. Carbonates can be formed from these formulations. It may also contain 30% by weight of ammonium chloride, 20% by weight of potassium chloride, and 10% by weight of aluminum chloride. Chlorides can be formed by combining these. It may also contain 40% by weight of sodium hydroxide, 20% by weight of calcium hydroxide, and 10% by weight of magnesium hydroxide. Hydroxyl salts can be formed from these formulations. It may also contain 20% by weight of ammonium phosphate, 20% by weight of potassium phosphate, 10% by weight of calcium phosphate, and 10% by weight of magnesium phosphate. Phosphates can be formed from these formulations. One or more of the carbonates, chlorides, hydroxides, or phosphates may also be included.

[0094] On the other hand, the organic binder 120 can be mixed with the carbonate 121.

[0095] Furthermore, the organic binder 120 may contain one or more organic adhesives and elastomers. This allows the secondary battery fire suppressant 100 to take any form.

[0096] Figure 3 is a photograph showing the paste state of a secondary battery fire suppressant according to one embodiment of the present invention.

[0097] As shown in Figure 3, the fire suppressant for secondary batteries can be formed in a paste state by mixing it with an organic binder 120 containing one or more organic adhesives and rubbers.

[0098] As a specific example, the fire suppressant for the secondary battery shown in Figure 3 is a mixture of 80% by weight of carbonate and 20% by weight of soft polyurethane with organic binder 120.

[0099] Such a paste-like secondary battery fire suppressant can be applied to or coated on the inner surface of the case housing the secondary battery (corresponding to the battery pack cover 20 when referring to Figure 5).

[0100] If a fire occurs in a secondary battery and the temperature rises to a range deemed dangerous, each carbonate can be sequentially decomposed according to its decomposition initiation temperature, releasing carbon dioxide and cationic metal ions.

[0101] This allows the flammable gas generated from the secondary battery to be blocked from oxygen by the suffocating effect of carbon dioxide. Furthermore, lithium, which could cause ignition, is converted to lithium carbonate, making it non-flammable, and radicals generated by sparks are absorbed, thereby suppressing the spread of fire.

[0102] The secondary battery fire suppressant may be provided in the form of an elastic pad.

[0103] When multiple secondary batteries are provided, a secondary battery fire suppressant pad according to one embodiment of the present invention, provided in the form of a pad, can be positioned between at least one of the multiple secondary batteries.

[0104] When a fire breaks out in a secondary battery and heat is generated, reaching a temperature range deemed dangerous, each carbonate in the secondary battery fire suppressant pad decomposes sequentially according to the decomposition start temperature, releasing carbon dioxide and cationic metal ions. This can suppress the spread of the fire or extinguish it.

[0105] On the other hand, if necessary, the secondary battery fire suppressant 100 may further contain solid powder.

[0106] Figure 4 is a photograph showing a fire suppression member for a secondary battery according to one embodiment of the present invention, and Figure 5 is an exploded view of the interlayers of the fire suppression member for a secondary battery according to one embodiment of the present invention.

[0107] As shown in Figures 4 and 5, the secondary battery fire suppression member 1000 may include a pair of fiber members 210 and 220 and a secondary battery fire suppressant 100.

[0108] The pair of fiber members 210 and 220 may be non-flammable fiber members. The secondary battery fire suppressant 100 may be provided between the pair of fiber members 210 and 220.

[0109] In this embodiment, the secondary battery fire suppression member 1000 may be formed by first applying a paste-like secondary battery fire suppressant 100 to one of the fiber members 220, and then covering it with another fiber member 210. A coater may be used for coating the paste-like secondary battery fire suppressant 100.

[0110] Alternatively, the secondary battery fire suppression member 1000 may be formed by first molding the secondary battery fire suppressant 100 into a pad shape, and then attaching a pair of fiber members 210 and 220 to both sides of the pad-shaped secondary battery fire suppressant pad.

[0111] The secondary battery fire suppression member 1000 may be provided so as to cover at least a portion of the secondary battery. Referring to Figure 4, the secondary battery fire suppression member 1000 may be provided so as to cover the battery pack 10 inside the battery pack cover 20.

[0112] Since the secondary battery fire suppression member 1000 can be formed to conform to the shape of the battery pack 10, it can stably cover the entire battery pack 10.

[0113] When a fire breaks out in a secondary battery and the temperature rises to a dangerous temperature range, the carbonate in the secondary battery fire suppression member 1000 decomposes sequentially according to the decomposition start temperature, and carbon dioxide and cationic metal ions may be ejected. Through this, the spread of the fire can be suppressed or extinguished.

[0114] As shown in Figure 5, the secondary battery fire suppression member 1000 may also include a pair of fiber members 210, 220, a secondary battery fire suppressant 100, a heating wire 300, and a switch 400.

[0115] The pair of fiber members 210, 220 and the secondary battery fire suppressant 100 may be the same as those described in Figures 4 and 5.

[0116] The heating element 300 may be placed on one of the pair of fiber members 210, 220, specifically on fiber member 220. The heating element 300 can be in direct contact with the secondary battery fire suppressant 100. The heating element 300 may also be connected to the secondary battery 11.

[0117] The switch 400 can then be connected to the heating element 3W. In one embodiment, the switch 400 can be connected to the heating element 300 on the outside of the fiber member 220.

[0118] When the detected temperature exceeds a preset allowable temperature, the switch 400 can cause the secondary battery 11 to apply current to the heating element 300 located in the fiber member 220, thereby heating the heating element 300. The heating element 300 can be heated in Joules. Here, the allowable temperature may be a hazardous temperature required by the user.

[0119] Therefore, if a fire occurs and the temperature exceeds the dangerous temperature, the current from the secondary battery 11 may be applied to the heating element 300, causing it to heat up. The heat from the heating element 300 may then decompose the carbonate.

[0120] At this time, the heating element 300 may be heated to a temperature corresponding to the lowest decomposition initiation temperature of the powder contained in the fire extinguishing material, thereby allowing the powder with the lowest decomposition initiation temperature to undergo primary decomposition. If the fire is not brought under control in the primary fire extinguishing process, the temperature will rise, and secondary and tertiary fire extinguishing processes may then proceed.

[0121] The switch 400 may be configured to allow setting of an acceptable temperature according to the hazardous temperature required by the user. This allows the starting temperature of the fire suppression process of the secondary battery's fire suppression member 1000 to be easily and accurately set to match the diverse hazardous temperatures required by different users.

[0122] For example, the switch 400 can be configured to include a bimetallic strip that enables automatic switching operation depending on the temperature.

[0123] Furthermore, the secondary battery fire suppression member 1000 may further include a temperature sensor unit 500 for temperature sensing. In this case, the switch 400 may be configured to switch based on the temperature sensed by the temperature sensor unit 500.

[0124] On the other hand, the secondary battery fire suppression member 1000 is not limited to sensing temperature, but can also sense other things. For example, the secondary battery fire suppression member 1000 can also sense pressure.

[0125] When pressure is the target of detection, the secondary battery fire suppression member 1000 may further include a pressure sensor (not shown).

[0126] The pressure sensor unit can sense the internal pressure of the secondary battery 11.

[0127] If a fire occurs and the internal pressure of the secondary battery 11 increases, and the sensed pressure exceeds a preset allowable pressure, the switch 400 can be configured to apply current from the secondary battery 11 to the heating element 300 located in the fiber member 220, thereby heating the heating element 300.

[0128] The above description of the present invention is illustrative, and a person with ordinary skill in the art to which the invention pertains will understand that it can be easily modified into other specific forms without altering the technical idea or essential features of the invention. Accordingly, the embodiments described above should be understood to be illustrative and not limiting in all respects. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0129] The scope of the present invention is defined by the claims described below, and all modifications or alterations derived from the meaning and scope of the claims and the concept of equivalents thereof should be interpreted as being included within the scope of the present invention. [Explanation of Symbols]

[0130] 10: Battery Pack 11: Secondary battery 20: Battery pack cover 100: Secondary battery fire suppressant 110: Fire extinguishing substances 120: Organic Binder 210, 220: Fiber members 300: Heating wire 400: Switch 500: Temperature sensor unit 1000: Secondary battery fire suppression component

Claims

1. A fire suppressant comprising one or more first substances having a decomposition initiation temperature, and a second substance mixed with the first substances to bind them, wherein the first substances decompose when they reach the decomposition initiation temperature, thereby decomposing flammable organic compounds.

2. The fire suppressant according to claim 1, wherein the first substance is a fire extinguishing substance and the second substance is an organic binder.

3. The fire suppressant according to claim 2, wherein the fire extinguishing substance comprises two or more fire extinguishing substances, the two or more fire extinguishing substances have two or more decomposition initiation temperatures, and can decompose stepwise to make the flammable organic compound non-flammable.

4. The fire suppressant according to claim 1, wherein the first substance comprises one or more of carbonates, chlorides, hydroxides, and phosphates, and can deflammate flammable organic compounds.

5. The carbonate is sodium carbonate (Na ２ CO ３ ), sodium bicarbonate (NaHCO ３ ), potassium carbonate (K ２ CO ３ ), potassium bicarbonate (KHCO ３ ), ammonium carbonate ((NH ４ ) ２ CO ３ ), ammonium bicarbonate (NH ４ HCO ３ ), and includes one or more of them, and can render the combustible organic compound non-combustible. The fire suppressant according to claim 4

6. The aforementioned chloride is ammonium chloride (NH ４ Cl), potassium chloride (KCl), aluminum chloride (AlCl ３ The fire suppressant according to claim 4, comprising one or more of the following: ), sodium chloride (NaCl), and capable of making flammable organic compounds non-flammable.

7. The hydroxides mentioned above are sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (Ca(OH) ２ ), magnesium hydroxide (Mg(OH) ２ The fire suppressant according to claim 4, comprising one or more of the above, which can make flammable organic compounds non-flammable.

8. The phosphate is ammonium phosphate ((NH ４ ) ３ PO ４ ), sodium phosphate (Na ３ PO ４ ), potassium phosphate (K ３ PO ４ The fire suppressant according to claim 4, comprising one or more of the above, which can make flammable organic compounds non-flammable.

9. The fire suppressant according to claim 2, wherein the fire suppressant is provided in one or more phases from among paste, liquid, and gaseous.

10. The fire suppressant according to claim 1, wherein the second substance comprises one or more organic adhesives and elastomers, and can make flammable organic compounds non-flammable.

11. A pair of fibrous members, one or more fire-extinguishing substances provided between the pair of fibrous members, having a decomposition initiation temperature, which decomposes upon reaching the decomposition initiation temperature to render flammable organic compounds non-flammable, and A fire suppression member comprising a fire suppressant containing an organic binder mixed with the aforementioned fire-extinguishing substance, which can deflammable organic compounds.

12. A secondary battery comprising one or more fire-extinguishing substances having a decomposition initiation temperature, and an organic binder mixed with the fire-extinguishing substances, wherein the fire-extinguishing substances include a fire suppressant that decomposes upon reaching the decomposition initiation temperature, thereby rendering flammable organic compounds non-flammable.

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