Fire extinguishing agent for battery

Abstract

The present invention relates to a fire extinguishing agent for a battery, and provides a fire extinguishing agent capable of completely blocking a fire in the event of a battery fire, thereby realizing low cost and eco-friendliness.

Description

Fire extinguishing agent for batteries

[0001] The present invention relates to a fire extinguishing agent for batteries that can completely block a fire when a battery fire occurs, thereby enabling low cost and environmental friendliness.

[0002] In addition, the present invention relates to the Ulsan National Institute of Science and Technology internal project (Project No.: 2.241124.01) “Synthesis and performance verification of battery fire-retardant material FPM utilizing freezing point depression”.

[0003]

[0004] In the case of lithium-ion batteries (Li-ion batteries), there is a risk of fire because flammable organic materials are used as electrolytes. Furthermore, fires accompanied by thermal runaway can occur due to the provision of ignition points resulting from electrode short circuits and the supply of oxygen resulting from anode decomposition. In particular, as the ESS and EV markets grow, multiple batteries are used in the form of modules and packs. Consequently, high energy density and the concentration of numerous battery cells can lead to large-scale fires, potentially expanding the scale of fire damage. Therefore, there is a need for battery fire extinguishing agents.

[0005] Meanwhile, conventional battery fire extinguishing agents are based on solid materials and present problems such as the potential generation of harmful gases like hydrogen fluoride (HF) and the need to use expensive chemicals. Furthermore, in the case of solid aerosol fire extinguishing films, the potassium (K) in the solid aerosol attached to the film combines with oxygen upon combustion to extinguish the fire by suffocation, but it also generates harmful byproducts (such as NH3) and poses a risk of re-ignition due to insufficient cooling capabilities.

[0006] Accordingly, there is a need to develop a fire extinguishing agent composition that can achieve low cost and eco-friendliness by enabling the complete prevention of fire in the event of a battery fire.

[0007]

[0008] (Prior Art) Korean Patent Publication No. 10-2018-0128790

[0009]

[0010] The objective of the present invention is to provide a fire extinguishing agent for batteries that has improved wettability, processability, a low freezing point, and improved insulation properties.

[0011]

[0012] To achieve the above objective, a fire extinguishing agent for a battery according to one embodiment of the present invention comprises a high specific heat liquid; an oxygen-blocking polymer; an organic liquid; and an oxygen-blocking inorganic material.

[0013] The above high specific heat liquid may include distilled water (DI water), ammonia, or silicon oil.

[0014] The oxygen barrier polymer may be one or more selected from the group consisting of polyvinyl alcohol, polyethylene glycol, polyacrylic acid, polyacrylic acid derivatives, polysaccharides, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polydiallyldimethyl ammonium chloride, xanthan gum, guar gum, gelatin, pectin, cellulose derivatives, starch derivatives, alginate, and chitosan.

[0015] The above organic liquid may be ethylene glycol and / or propylene glycol.

[0016] The above oxygen-blocking mineral may be fumed silica and / or vermiculite.

[0017] Based on 100 wt% of the battery fire extinguishing agent composition, the high specific heat liquid may be 30 to 60 wt%, the oxygen blocking polymer 1 to 5 wt%, the organic liquid 35 to 65 wt%, and the oxygen blocking inorganic material 1 to 5 wt%.

[0018] More specifically, the high specific heat liquid may be 39.25 to 52 wt%, the oxygen blocking polymer 3.75 to 5 wt%, the organic liquid 42 to 55.65 wt%, and the oxygen blocking inorganic material 1 to 1.35 wt%.

[0019]

[0020] The present invention provides a high-viscosity fire extinguishing agent based on a high-viscosity liquid, and at the same time has the effect of creating an oxygen barrier that adheres to the surface of the combustible material at high temperatures.

[0021] In addition, the present invention can lower the temperature of the battery surface when a battery fire occurs and prevent temperature transfer to surrounding battery cells or battery modules.

[0022] In addition, the present invention has the effect of being able to be used effectively even at low temperatures due to its low freezing point and low volume expansion rate.

[0023] In addition, since the present invention does not contain salt, it has low corrosiveness and has the effects of high insulation, eco-friendliness, and low toxicity.

[0024]

[0025] Figure 1 illustrates the manufacturing process of a fire extinguishing agent for batteries according to one embodiment of the present invention.

[0026] Figure 2 illustrates the viscosity analysis results for a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0027] Figure 3 illustrates the results of a thermogravimetric analysis of a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0028] Figure 4 shows a photographic image of the flowability analysis of a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0029] Figure 5 illustrates the results of the decomposition temperature analysis for a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0030] Figure 6 illustrates the results of a specific heat analysis for a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0031] FIG. 7 illustrates the results of a low-capacity battery single-cell thermal runaway test for a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0032] FIG. 8 illustrates a cell-specific photographic image for a thermal runaway test of an electric scooter high-capacity battery module for a battery fire extinguishing agent according to one embodiment of the present invention.

[0033] FIG. 9 illustrates the results of a thermal runaway transfer test of a large-capacity electric scooter battery module for a fire extinguishing agent for a battery according to one embodiment of the present invention.

[0034]

[0035] A fire extinguishing agent for a battery according to one embodiment of the present invention comprises a high specific heat liquid; an oxygen-blocking polymer; an organic liquid; and an oxygen-blocking inorganic material.

[0036] The above high specific heat liquid may include distilled water (DI water), ammonia, or silicon oil.

[0037] The oxygen barrier polymer may be one or more selected from the group consisting of polyvinyl alcohol, polyethylene glycol, polyacrylic acid, polyacrylic acid derivatives, polysaccharides, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polydiallyldimethyl ammonium chloride, xanthan gum, guar gum, gelatin, pectin, cellulose derivatives, starch derivatives, alginate, and chitosan.

[0038] The above organic liquid may be ethylene glycol and / or propylene glycol.

[0039] The above oxygen-blocking mineral may be fumed silica and / or vermiculite.

[0040] Based on 100 wt% of the battery fire extinguishing agent composition, the high specific heat liquid may be 30 to 60 wt%, the oxygen blocking polymer 1 to 5 wt%, the organic liquid 35 to 65 wt%, and the oxygen blocking inorganic material 1 to 5 wt%.

[0041]

[0042] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0043]

[0044] A fire extinguishing agent for a battery according to one embodiment of the present invention relates to a fire extinguishing agent composition based on a liquid, wherein the fire extinguishing agent for a battery comprises a cooling solution; and a suspension that lowers the freezing point. More specifically, the fire extinguishing agent for a battery comprises a high specific heat liquid; an oxygen-blocking polymer; an organic liquid; and an oxygen-blocking inorganic material.

[0045] At this time, based on 100 wt% of the fire extinguishing agent composition for the battery, the high specific heat liquid may be included in an amount of 30 to 60 wt%, the oxygen blocking polymer in an amount of 1 to 5 wt%, the organic liquid in an amount of 35 to 65 wt%, and the oxygen blocking inorganic material in an amount of 1 to 5 wt%.

[0046] In addition, more specifically, based on 100 wt% of the fire extinguishing agent composition for the battery, the high specific heat liquid may be 39.25 to 52 wt%, the oxygen blocking polymer may be 3.75 to 5 wt%, the organic liquid may be 42 to 55.65 wt%, and the oxygen blocking inorganic material may be 1 to 1.35 wt%.

[0047]

[0048] The above-mentioned high-specific-heat liquid; and the above-mentioned oxygen-blocking polymer constitute the cooling solution, wherein the cooling solution has a cooling effect in the event of a battery fire and simultaneously forms an oxygen-blocking film.

[0049] The above high specific heat liquid has high thermal conductivity and simultaneously has a high specific heat, and is capable of lowering the temperature in the event of a fire, and the above high specific heat liquid may include distilled water (DI water), ammonia, or silicon oil.

[0050] Based on 100 wt% of the fire extinguishing agent composition for the battery, the high specific heat liquid may be 30 to 60 wt%, and preferably 39.25 to 52 wt%.

[0051]

[0052] The above oxygen-blocking polymer may prevent the high-specific-heat liquid in the cooling solution from boiling in the event of a fire, and at the same time form a non-combustible film on the surface of the combustible material (e.g., battery) to block the combustible material from air.

[0053] Based on 100 wt% of the fire extinguishing agent composition for the battery, the oxygen blocking polymer may be 0.1 to 5 wt%, and preferably 3.75 to 5 wt%.

[0054] The oxygen barrier polymer may be one or more selected from the group consisting of polyvinyl alcohol, polyethylene glycol, polyacrylic acid, polyacrylic acid derivatives, polysaccharides, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polydiallyldimethyl ammonium chloride, xanthan gum, guar gum, gelatin, pectin, cellulose derivatives, starch derivatives, alginate, and chitosan.

[0055] The above cellulose derivative may be one or more selected from the group consisting of carboxymethyl cellulose, hydroxyethyl cellulose, and methyl cellulose.

[0056]

[0057] The above organic liquid; and the above oxygen-blocking inorganic material constitute the suspension, wherein the suspension suppresses a fire by raising the combustion point of a combustible material (e.g., battery) when a fire occurs, and enables the effective use of a fire extinguishing agent even at low temperatures by lowering the freezing point and reducing the volume expansion rate.

[0058] The above organic liquid lowers the freezing point and lowers the volume expansion rate, and the above organic liquid may be ethylene glycol and / or propylene glycol.

[0059] Based on 100 wt% of the fire extinguishing agent composition for the battery, the organic liquid may be 35 to 65 wt%, and more preferably 42 to 55.65 wt%.

[0060]

[0061] The oxygen-blocking inorganic material may not burn in a fire as the decomposition temperature of the fire extinguishing agent for the battery increases, and may form a non-combustible film on the surface of the combustible material (e.g., battery) to block the combustible material from air. The oxygen-blocking inorganic material may be fumed silica and / or vermiculite.

[0062] Based on 100 wt% of the fire extinguishing agent composition for the battery, the oxygen-blocking inorganic material may be 0.1 to 5 wt%, and more preferably 1 to 1.35 wt%.

[0063]

[0064] The present invention will be explained in more detail below through examples. These examples are merely illustrative for understanding the invention and do not limit the scope of the invention.

[0065]

[0066] Example 1. Method for manufacturing a fire extinguishing agent for batteries

[0067] Referring to FIG. 1, a method for manufacturing a fire extinguishing agent for a battery according to one embodiment of the present invention will be described.

[0068] 10 g of PVA (polyvinyl alcohol) is dissolved in 104 g of distilled water as a high specific heat liquid to prepare 114 g of an aqueous PVA solution as a cooling solution, and then the solution is cooled at room temperature until the color of the solution becomes transparent.

[0069] 2 g of fumed silica is added to 84 g of ethylene glycol to prepare 86 g of suspension.

[0070] A fire extinguishing agent for batteries is prepared by mixing 114 g of a manufactured PVA aqueous solution (cooling solution) and 86 g of a suspension (cooling solution:suspension = 6:4 (w:w)).

[0071]

[0072] Example 2. Method for manufacturing a fire extinguishing agent for batteries

[0073] Referring to FIG. 1, a method for manufacturing a fire extinguishing agent for a battery according to one embodiment of the present invention will be described.

[0074] 7.5 g of polyvinyl alcohol (PVA) is dissolved in 78.5 g of distilled water as a high specific heat liquid to prepare 86 g of an aqueous PVA solution as a cooling solution, and then the solution is cooled at room temperature until it becomes transparent.

[0075] 2.7 g of fumed silica is added to 111.3 g of ethylene glycol to prepare a suspension of 114 g.

[0076] A fire extinguishing agent for batteries is prepared by mixing 86 g of a manufactured PVA aqueous solution (cooling solution) and 114 g of a suspension (cooling solution:suspension = 4:6 (w:w)).

[0077]

[0078] The composition ratio (wt%) of each material in the battery fire extinguishing agents prepared in Examples 1 and 2 above is as shown in Table 1 below.

[0079] Classification Distilled Water PVA Ethylene Glycol Fumed Silica Example 152 wt% 5 wt% 42 wt% 1 wt% Example 239.25 wt% 3.75 wt% 55.65 wt% 1.35 wt%

[0080]

[0081] Experimental Example 1. Analysis of High Viscosity of Fire Extinguishing Agents

[0082] The viscosity of the fire extinguishing agent prepared in Example 1 above was measured using a BROOKFIELD AMETEK DV-1 Viscometer, and the viscosity of water and silicone oil was measured together as a control group and is shown in FIG. 2. Referring to FIG. 2, the viscosity of the fire extinguishing agent of the example can be confirmed to be 1000 to 2000 cp, and it can be confirmed that it has relatively high viscosity compared to the control group (water, silicone oil).

[0083]

[0084] Experimental Example 2. Low freezing point of fire extinguishing agent

[0085] The heat flow according to temperature was analyzed for the fire extinguishing agent prepared in Example 1 above using the TA Instrument-Q200 DSC equipment and is shown in Fig. 3(a), and the same measurement was taken for water as a control and is shown in Fig. 3(b).

[0086] Referring to Fig. 3, the presence of phase change and the freezing and melting points can be determined by identifying the material properties. As shown in Fig. 3 (b), the control group undergoes a phase change and produces a sharp peak (red dotted circle), whereas Example 1 in Fig. 3 (a) shows that no phase change occurs up to -40℃ and has a flat region.

[0087] Additionally, photographic images of the fire extinguishing agent prepared in Example 1 and the control group, respectively, after being stored in a freezer set to -20°C for at least 4 hours and then visually inspected, are shown in Fig. 4.

[0088] Referring to Fig. 4(a), it can be seen that the fire extinguishing agent prepared in Example 1 does not freeze and maintains flowability even after being stored in a freezer set to -20°C for more than 4 hours. On the other hand, referring to Fig. 4(b), it can be seen that the control group becomes opaque and does not show flowability as crystallization occurs while freezing.

[0089]

[0090] Experimental Example 3. High decomposition temperature of fire extinguishing agent

[0091] Figure 5 shows the results of thermogravimetric analysis measured using a TA Instrument-Q500 TGA instrument for the fire extinguishing agent prepared in Example 1 above. Referring to Figure 5, 1.2% of the mass is maintained even at temperatures above 700°C, which confirms that it can withstand high temperatures (above 700°C) without burning or completely decomposing.

[0092]

[0093] Experimental Example 4. Analysis of Electrical Conductivity of Fire Extinguishing Agent

[0094] The electrical conductivity of the fire extinguishing agent prepared in Example 1 was measured using a Thermo Fischer Orionstar Conductivity meter, and the measurement result was 77.43 μS / cm. Meanwhile, considering that the electrical conductivity of commercially available concentrated coolant for eco-friendly vehicles is 1050–1150 μS / cm, the electrical conductivity of the fire extinguishing agent in Example 1 can be seen as a low value.

[0095]

[0096] Experimental Example 5. Acidity Measurement

[0097] It can be confirmed that the pH of the fire extinguishing agent prepared in Example 1 was measured to be approximately 5.547 using a Thermo Fischer Orion Vera Star Pro pH meter, which indicates that it is very weakly acidic, and thus the fire extinguishing agent of Example 1 is expected to have low corrosiveness.

[0098]

[0099] Experimental Example 6. Specific Heat Analysis of Fire Extinguishing Agents

[0100] The specific heat of the fire extinguishing agent prepared in Example 1 above was measured using Differential Scanning Calorimetry (DSC) from NETZSCH, a thermal analysis laboratory at Ajou University, and the results are shown in Fig. 6. Referring to Fig. 6, the measurement result was 3.597 J / g·K, confirming that it has a high specific heat at room temperature (25 ℃). Among liquids, water has the highest specific heat at 4.144 J / g·K, which is not much different from the developed fire extinguishing agent and is still a very high value compared to other substances.

[0101]

[0102] Experimental Example 7. Analysis of Thermal Conductivity of Fire Extinguishing Agent

[0103] The thermal conductivity of the fire extinguishing agents prepared in Examples 1 and 2 above was measured several times using a thermal conductivity meter (LFA457) from NETZSCH, Ajou University Thermal Analysis Laboratory, and the results are summarized in Table 2 (Example 1) and Table 3 (Example 2) below. Referring to Tables 2 and 3, the average thermal conductivity of the fire extinguishing agents in the above examples was confirmed to be 452 mW / m·K. This is evaluated to be higher than that of existing materials as shown in Table 4 below, and it is predicted that it will effectively dissipate the generated heat.

[0104] Measurement timesTemperature(℃)Conductivity(W / m·K)Diffusitivy(mm 2 / s)Cp(J / g·K)Laser voltage(V)Puse widthe(ms)1250.4500.1123.5972300.302250.4520.1133.5972300.303250.4530.1133.5972300.304250.4500.1133.5972300.305250. 4500.1133.5972300.306250.4530.1133.5972300.307250.4530.1133.5972300.308250.4530.1133.5972300.30Mean250.4520.1133.597

[0105] Measurement timesTemperature(℃)Conductivity(W / m·K)Diffusitivy(mm 2 / s)Cp(J / g·K)Laser voltage(V)Puse widthe(ms)1250.3920.1133.2172300.302250.3920.1123.2172300.303250.3890.1123.2172300.304250.3930.1133.2172300.305250. 3890.1123.2172300.306250.3900.1123.2172300.307250.3920.1133.2172300.308250.3890.1123.2172300.30Mean250.3910.1123.217

[0106] SubstanceThermal conductivity (W m -1 ·K -1 Air 0.026 Styrofoam 0.033 Water 0.60 89 Castor Oil 0.180 Ethanol 0.171

[0107]

[0108] Experimental Example 8. Thermal Runaway Test of a Low-Capacity Single Cell Battery

[0109] An experiment was conducted to forcibly induce thermal runaway in a 100 mAh low-capacity pouch battery by overcharging. When thermal runaway occurred, the results when the extinguishing agent from Example 1 was applied are shown in FIG. 7 (a), the results when not applied (external air) are shown in FIG. 7 (b), and the results when a fluorocarbon-based extinguishing agent was applied are shown in FIG. 7 (c). Referring to FIG. 7, when battery thermal runaway occurred, the maximum temperature rose to 499.7 ℃ in FIG. 7 (b) when not applied (external air) and to 498.3 ℃ when the fluorocarbon-based extinguishing agent was applied in FIG. 7 (c), whereas when the extinguishing agent from Example 1 was applied as shown in FIG. 7 (a), the temperature decreased by up to 160 ℃ compared to the control material ( FIG. 7 (b) and (c)).

[0110]

[0111] Experimental Example 9. Thermal Runaway Transition Test of High-Capacity Electric Scooter Battery

[0112] As shown in FIG. 8, a thermal runaway test was performed on a 13S 4P battery module used in an electric scooter, and the thermal runaway cell (“TR cell”), adjacent cell 1 (“T1 cell”) and adjacent cell 2 (“T2 cell”) adjacent to the thermal runaway cell are indicated in FIG. 8.

[0113] As shown in FIG. 8, the test results of the thermal runaway cell (“TR cell”), adjacent cell 1 (“T1 cell”), and adjacent cell 2 (“T2 cell”) according to the case of causing thermal runaway, and a photographic image of the thermal runaway cell (“TR cell”) are shown in FIG. 9 (a).

[0114] In addition, the test results of the thermal runaway cell (“TR cell”), adjacent cell 1 (“T1 cell”), and adjacent cell 2 (“T2 cell”) and a photographic image of the thermal runaway cell (“TR cell”) are shown in FIG. 9(b), in the case where thermal runaway occurs when the fire extinguishing agent prepared in Example 1 is applied. In FIG. 9(b), the fire extinguishing agent prepared in Example 1 is positioned to surround the surface of the thermal runaway cell (“TR cell”).

[0115] Referring to Fig. 9(a), it can be seen that the battery module has been completely burned (right image of Fig. 9(a)).

[0116] Meanwhile, referring to FIG. 9(b), when the fire extinguishing agent of Example 1 is applied, the fire caused by thermal runaway of the electric scooter battery module is immediately extinguished and the degree of battery damage is significantly reduced. Furthermore, it can be confirmed through the test result graph (left image of FIG. 9(b)) that adjacent cells (“T1 cell”, “T2 cell”) are unburned, and the remaining fire extinguishing agent (fire extinguishing agent in Example 1) can be confirmed through the right image of FIG. 9(b).

[0117]

[0118] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

1. A high specific heat liquid; an oxygen barrier polymer; an organic liquid; and an oxygen barrier inorganic material comprising, Fire extinguishing agent for batteries.

2. In Paragraph 1, The above high specific heat liquid comprises distilled water (DI water), ammonia, or silicon oil. Fire extinguishing agent for batteries.

3. In Paragraph 1, The oxygen barrier polymer is one or more selected from the group consisting of polyvinyl alcohol, polyethylene glycol, polyacrylic acid, polyacrylic acid derivatives, polysaccharides, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polydiallyldimethyl ammonium chloride, xanthan gum, guar gum, gelatin, pectin, cellulose derivatives, starch derivatives, alginate, and chitosan. Fire extinguishing agent for batteries.

4. In Paragraph 1, The above organic liquid is ethylene glycol and / or propylene glycol, Fire extinguishing agent for batteries.

5. In Paragraph 1, The above oxygen-blocking mineral is fumed silica and / or vermiculite, Fire extinguishing agent for batteries.

6. In Paragraph 1, The above high specific heat liquid is 30 to 60 wt%, the above oxygen barrier polymer is 1 to 5 wt%, the above organic liquid is 35 to 65 wt%, and the above oxygen barrier inorganic material is 1 to 5 wt%. Fire extinguishing agent for batteries.

7. In Paragraph 1, The above high specific heat liquid is 39.25 to 52 wt%, the above oxygen barrier polymer is 3.75 to 5 wt%, the above organic liquid is 42 to 55.65 wt%, and the above oxygen barrier inorganic material is 1 to 1.35 wt%. Fire extinguishing agent for batteries.

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