CN119034150A

CN119034150A - Fire-fighting sand for battery cooling and preparation method and application thereof

Info

Publication number: CN119034150A
Application number: CN202411106043.8A
Authority: CN
Inventors: 张玉; 方淳; 黄志梅; 刘磊; 吴仕; 闫安; 吴小员
Original assignee: Nanjing Litai New Energy Technology Co ltd; HUST Wuxi Research Institute
Current assignee: Nanjing Litai New Energy Technology Co ltd; HUST Wuxi Research Institute
Priority date: 2024-08-13
Filing date: 2024-08-13
Publication date: 2024-11-29

Abstract

The present invention discloses a fire sand for cooling batteries and its preparation method and application, and relates to the technical field of fire extinguishing agents. The fire sand for cooling batteries is characterized in that it comprises: a liquid core and a core shell containing fire extinguishing components, and the two components are combined into the fire sand through high-speed stirring; wherein the components of the liquid core include: a flame retardant, a fluorocarbon surfactant, a nonionic surfactant, a gelling agent, and deionized water; the core shell is a hydrophobic granular material, and the fire sand is used with a dry powder fire extinguishing agent nozzle for cooling when the ambient temperature of the lithium energy storage battery rises rapidly and thermal runaway is about to occur. The fire extinguishing agent of the present invention can not only isolate oxygen when covering the surface of the lithium battery, but also absorb a large amount of heat through the evaporation of water inside the gel, so as to achieve the purpose of cooling and preventing thermal runaway of the battery cell.

Description

Fire-fighting sand for battery cooling and preparation method and application thereof

Technical Field

The invention relates to the technical field of fire extinguishing agents, in particular to fire-fighting sand for battery cooling and a preparation method and application thereof.

Background

The common fire extinguishing agents at present are foam fire extinguishing agents, dry powder fire extinguishing agents, water mist fire extinguishing agents, carbon dioxide fire extinguishing agents, aerosol fire extinguishing agents and the like. These extinguishing agents have a good effect on the initial fire suppression. However, the foam extinguishing agent has poor high temperature resistance, the extinguishing residue possibly pollutes the environment or needs special treatment, the water mist extinguishing agent has poor low temperature resistance, low auxiliary agent concentration and long extinguishing time, can cause water stain hazard, the powder extinguishing agent has general cooling effect, weak reburning resistance and is easy to reburning, and the aerosol extinguishing agent has complex production process flow and high cost and is unfavorable for large-scale popularization. The development of a novel fire extinguishing material with low cost and high fire extinguishing efficiency is one of the current research hotspots.

The dry water is white tiny powder, and is a core-shell structure formed by mixing hydrophobic silicon dioxide and aqueous solution which are mutually insoluble, and the water content can reach more than 60%. The fire extinguishing mechanism of the dry water is fine white powder particles with a core-shell structure, and the dry water is decomposed when meeting heat, and the purposes of cooling and extinguishing fire are achieved through the fire extinguishing mechanisms such as cooling effect, dilution oxygen effect, non-uniform chemical effect and the like. For lithium batteries, thermal runaway is initiated when the heat generated inside the lithium battery exceeds its potential to dissipate heat. Such imbalance often causes adverse chemical reactions and increases the temperature, which in turn causes explosions or fires. The dry water extinguishing agent can cover the surface of the battery, plays a role in isolating oxygen and continuously cooling, and reduces the danger of the battery and further causes thermal runaway. The dry water powder has little residual quantity after fire extinguishment, no volatile matters, no toxicity and no harm, and is an ideal fire extinguishment cooling material.

Disclosure of Invention

This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application.

The invention is provided in view of the problems of the prior fire-fighting sand for battery cooling, the preparation method and the application thereof.

The invention provides a technical scheme for solving the technical problems, which comprises a liquid core and a core shell which contain fire extinguishing components, and combining the two components into the fire extinguishing sand through high-speed stirring;

Wherein the liquid core comprises a flame retardant, a fluorocarbon surfactant, a nonionic surfactant, a gel and deionized water;

The core shell is a hydrophobic particulate material.

As a preferable scheme of the fire-fighting sand aiming at battery cooling, the fire retardant is one or more of ammonium dihydrogen phosphate, ammonium polyphosphate, trimethyl phosphate, dimethyl methylphosphonate, potassium chloride and potassium bicarbonate.

As a preferable scheme of the fire-fighting sand for battery cooling, the fluorocarbon surfactant is one or more of 1157, 1470, 1440, 1460, 1183 and 1475.

As a preferable scheme of the fire-fighting sand aiming at battery cooling, the nonionic surfactant is one or more of Tween 80, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, BAC-12, CAB-35 and imidazoline.

As a preferable scheme of the fire-fighting sand for battery cooling, the gel is one or more of gellan gum, xanthan gum, carboxymethyl cellulose, sodium alginate, carrageenan, agar and polyvinyl alcohol.

As a preferable scheme of the fire-fighting sand aiming at battery cooling, the core-shell is one or more of hydrophobic silicon dioxide (7-40 nm), titanium dioxide, aluminum oxide, montmorillonite and bentonite.

As a preferable scheme of the fire-fighting sand for battery cooling, the mass ratio of the liquid core to the core-shell material is (85-95): 5-15.

In addition, the invention also provides a preparation method of the fire-fighting sand aiming at battery cooling, which comprises the following steps:

Firstly, mixing a flame retardant, a fluorocarbon surfactant, a nonionic surfactant, a gel and deionized water according to a certain proportion to obtain a liquid core solution;

And secondly, selecting one or more of hydrophobic silica with the particle size of 7-40nm, titanium dioxide, aluminum oxide, montmorillonite and bentonite as a core shell, and stirring the core shell and the filter element solution prepared in the first step in stirring equipment with high rotating speed for not less than 30 seconds to prepare the sand control agent.

As a preferable scheme of the fire-fighting sand for battery cooling and the preparation method and application thereof, the liquid core comprises, by mass, 10-15% of flame retardant, 0.1-2% of fluorocarbon surfactant, 0.1-5% of nonionic surfactant, 1-5% of gelling agent and the balance deionized water.

The application of the fire-fighting sand for cooling the battery aims at the rapid rise of the environmental temperature of the lithium battery energy storage battery, and the fire-fighting sand is matched with a dry powder extinguishing agent nozzle for cooling when thermal runaway is about to happen.

The multifunctional dry water fire extinguishing agent prepared by the preparation method has the beneficial effects that the dry water powder fire extinguishing agent is in a structure that small gel drops are wrapped by hydrophobic nano particles. Aiming at oil fire or wood fire, in the fire extinguishing process, powder can be attached to the surface of a combustion object to play roles in isolating air and preventing re-combustion, so that the utilization rate of water is improved, and meanwhile, chemical substances contained in a liquid core can generate chemical reaction in a fire disaster, so that the combustion capacity of the fire is reduced, and the fire disaster is extinguished. For the application in the aspect of lithium battery energy storage, because the energy storage space of lithium battery is limited, when the heat in the battery is gathered in a large amount, the temperature of the battery and the surrounding environment rises rapidly, thermal runaway is very easy to occur, and the fire extinguishing agent not only can isolate oxygen on the surface of the lithium battery, but also can absorb a large amount of heat through the evaporation of the water in the gel, thereby achieving the purpose of cooling and preventing the thermal runaway of the battery core.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

Fig. 1 is a schematic flow chart of a method for preparing fire-fighting sand for battery cooling;

fig. 2 is a schematic diagram showing the fire extinguishing time of the fire-fighting sand for battery cooling in example 5 and the comparison of the battery cooling rate.

Detailed Description

In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.

Further, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic can be included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

The embodiment 1 provides fire-fighting sand for battery cooling, a preparation method and application thereof, wherein the fire-fighting agent comprises a liquid core and a core shell which contain fire-fighting components, and the two components are combined into the fire-fighting sand through high-speed stirring;

The liquid core comprises a flame retardant, a fluorocarbon surfactant, a nonionic surfactant, a gel and deionized water, and the core shell is made of a hydrophobic particle material.

The fire-fighting sand is matched with a dry powder extinguishing agent nozzle to cool down when thermal runaway is about to occur aiming at the rapid rise of the ambient temperature of the lithium battery energy storage battery.

In the embodiment 1, referring to FIG. 1, the mass ratio of each component is (85-95) of flame retardant (10-15%), fluorocarbon surfactant (0.1-2%), nonionic surfactant (0.1-5%), gel (0.1-5%) and core-shell material (5-15).

The specific preparation method comprises the steps of firstly, heating 10g of monoammonium phosphate, 0.5g of 1157, 1g of sodium dodecyl sulfate, 1g of polyvinyl alcohol and 87.5g of deionized water at 40 ℃ and stirring at the rotating speed of 300r/min for 2 hours, cooling to room temperature, and successfully preparing a liquid core;

And step two, taking 5.3g of hydrophobic silica, mixing the hydrophobic silica with a liquid core at 5000r/min, and stirring for 30s to obtain the multifunctional dry water fire extinguishing agent.

Example 2

The multifunctional dry water fire extinguishing agent is prepared from (by mass) flame retardant 10-15%, fluorocarbon surfactant 0.1-2%, nonionic surfactant 0.1-5%, gel 0.1-5%, and liquid core and core-shell material at a mass ratio of (85-95) and (5-15).

The preparation method comprises the steps of firstly, heating 13g of monoammonium phosphate, 0.5g1157, 0.5g1470,1g of sodium dodecyl sulfate, 1g of APG-0810,2g of polyvinyl alcohol and 82g of deionized water, stirring for 2 hours at the temperature of 40 ℃ at the rotating speed of 300r/min, cooling to the room temperature, and successfully preparing a liquid core;

Example 3

The preparation method comprises the steps of firstly, heating 10g of ammonium polyphosphate, 2g of potassium chloride, 1.5g of 1470, 1g of APG-0810,2g of xanthan gum, 0.5g of carrageenan and 83g of deionized water at 50 ℃ and stirring at the rotating speed of 300r/min for 2 hours, cooling to room temperature, and successfully preparing a liquid core;

Step two, 10g of hydrophobic silicon dioxide and a liquid core are taken and stirred for 25 seconds at 6000r/min to obtain the multifunctional dry water fire extinguishing agent.

Example 4

A preparation method of a multifunctional dry water fire extinguishing agent comprises the following components, by mass, 10-15% of a flame retardant, 0.1-2% of a fluorocarbon surfactant, 0.1-5% of a nonionic surfactant, and 0.1-5% of a gel, wherein the mass ratio of a liquid core to a core-shell material is (85-95): 5-15.

Example 5

The preparation method comprises the following steps of firstly, heating 8g of dimethyl methylphosphonate, 2g of potassium bicarbonate, 1.5g of 1475, 1.5g of Tween 80, 2g of sodium alginate, 1g of carrageenan and 84 deionized water at 50 ℃ and stirring for 2 hours at the rotating speed of 300r/min, cooling to room temperature, and successfully preparing a liquid core;

And step two, 8g of hydrophobic silica and 2g of titanium dioxide are taken and mixed with the liquid core at 6000r/min, and the mixture is stirred for 25 seconds to obtain the multifunctional dry water fire extinguishing agent.

Comparative example 1

Tap water

Comparative example 2

Common commercial superfine dry powder extinguishing agent.

Comparative example 3

The preparation method of the common dry water powder comprises the steps of mixing hydrophobic nano silicon dioxide and deionized water according to a mass ratio of 1:10

Adding into a stirrer, stirring at 6000r/min for 30s to obtain the common dry water fire extinguishing agent.

The multifunctional dry water fire extinguishing agent prepared in examples 1-5, tap water in comparative example 1, dry powder fire extinguishing agent in comparative example 2 and dry water fire extinguishing agent in comparative example 3 are subjected to fire extinguishing test, the fire extinguishing performance of fire extinguishing agent B is tested according to GB 4066-2017 'dry powder fire extinguishing agent', the fire extinguishing effect is shown in table 1, and the fire source and the specific detection method are as follows:

In order to reduce the influence of environmental factors and manual operation on experimental results to the greatest extent, the fire extinguishing test is carried out in a room (5 m multiplied by 3.5 m), a dry water release device is arranged at the top of the room, the device consists of a pipeline, a fire extinguisher tank and a nozzle, wherein the inner diameter of a powder storage tank cylinder body of a 3kg special dry powder fire extinguishing device is about 350mm, the volume (12.0+/-0.2) L, the diameter of the nozzle of the device is about 9.5mm, and the jet orifice is positioned at the center from the bottom of an oil pan. The experimental steel oil pan has a diameter of 1884mm, a height of 200mm and a wall thickness of 2.5mm. The test fuel was industrial heptane. The room is provided with a high-temperature-resistant camera, so that the combustion and extinction process of the heptane can be observed conveniently. The release of dry water is achieved by controlling the valve of the fire extinguisher tank, while the spraying time is recorded by means of a stopwatch.

Referring to FIG. 2, the test procedure was to charge 3Kg of dry water into a powder storage tank, pressurize to 1.3MPa with nitrogen gas, adjust the device nozzle so that the lower edge of the nozzle is 2.30m from the horizontal ground. After 34L of water is added into the oil pan, 60L of fuel is poured into the oil pan, and the depth of the fuel at each point in the oil pan is not less than 15mm, but the depth of the liquid is not more than 50mm. Igniting, starting a stopwatch, pre-burning for 60s, and starting the fire extinguishing device. Each sample was subjected to 3 tests, the average value of 3 tests was taken as the final test result, and the test results are shown in table 1.

Type of extinguishing agent	Whether or not to extinguish fire	Extinguishing time/s
			Example 1	Is that	55’15
Example 2	Is that	56’00
			Example 3	Is that	52’49
Example 4	Is that	52’51
			Example 5	Is that	51’07
Comparative example 1	Whether or not	-
			Comparative example 2	Is that	67’80
Comparative example 3	Whether or not	-

TABLE 1

As can be seen from Table 1, the fire extinguishing effect can be achieved by the multifunctional dry water fire extinguishing agent prepared by the preparation method provided by the invention with the fire extinguishing time of 51-56s, the fire extinguishing time of the dry water fire extinguishing agent of comparative example 2 is about 67s, and the fire extinguishing is not achieved by the dry water fire extinguishing agent of comparative example 1 and tap water comparative example 3, which shows that the multifunctional dry water fire extinguishing agent prepared by the preparation method provided by the invention can achieve good fire extinguishing effect, and has low consumption and high fire extinguishing efficiency compared with the traditional fire extinguishing material.

Lithium battery cooling tests are carried out on the dry-water fire extinguishing agents obtained in examples 1-5 and comparative example 2 and the dry-powder fire extinguishing agent sold in the market in comparative example 1, wherein a square aluminum-shell lithium iron phosphate battery is adopted in the lithium battery cooling performance test, the rated capacity is 200 A.h, the mass of a battery monomer is 3950+/-100 g, the size of a lithium ion battery monomer is 170mm multiplied by 200mm multiplied by 53mm, and the state of charge (SOC) of an experimental battery is 100%. The powder storage tank has a volume of 12L, and the nozzle is a dry powder extinguishing agent nozzle. The dry water is applied and discharged in a pneumatic mode, a high-pressure nitrogen cylinder is connected with a powder storage tank, and the pressure is controlled to be applied by adjusting a pressure reducing valve on the cylinder.

Referring to fig. 2, an experimental platform is a PACK box, the size of the PACK box is 1060mm×800mm×220mm, a 200a·h lithium ion battery cell is placed at the northwest corner position of the box body, a heating plate and a lithium battery are fixed by using a fixed clamping plate, the power of the heating plate is 800W, thermocouples are arranged at the center position and two sides of the lithium battery, the thermocouples are used for monitoring the temperature change of the lithium battery in the fire extinguishing process, and 51 stainless steel false pieces with the same size as the lithium ion battery cell are closely placed at the rest positions.

The experimental process is that a heating device is started to heat the lithium battery until the temperature of the center of the battery core is increased to 300 ℃, and the heating device is closed. And spraying 12L of fire extinguishing agent into the PACK box, and recording the cooling rate of the lithium battery from the highest temperature to 100 ℃ in the fire extinguishing process. The cooling effect is shown in Table 2.

TABLE 2

From Table 2, it can be seen that the cooling rate of the lithium battery in examples 1-5 from the highest temperature to 100 ℃ is about 5.4 ℃ per second, and the temperature of the lithium battery in thermal runaway can be effectively reduced by about twice the proportion of 1-3, because the dry water structure is destroyed when the temperature is 300 ℃, the internal aqueous solution overflows, the heat of the combustion products is taken away by evaporation and heat absorption, the hydrophobic materials such as silicon dioxide coated on the surface belong to inert substances and are attached to the surface of the lithium battery, the surface of the lithium battery is isolated from oxygen, and the substances such as flame retardant and the like are added into the liquid core part to further absorb heat, so that the purposes of cooling and cooling are realized, and the occurrence of fire disaster is prevented. Tap water is sprayed onto the surface of the lithium battery, the safety valve of the battery core is exploded, part of water enters the safety valve and reacts with the inside of the battery severely to generate a large amount of dense smoke, so that the tap water is difficult to realize the coating effect on the lithium battery, and the cooling effect is relatively poor.

In conclusion, the preparation and application of the multifunctional dry water fire extinguishing agent provided by the invention can effectively extinguish class B open fire and effectively cool the lithium battery. The fire extinguishing agent has high cooling efficiency, convenient use and wide application range, and is an ideal fire extinguishing cooling material.

It should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered in the scope of the claims of the present invention.

Claims

1. The fire-fighting sand for battery cooling is characterized by comprising a liquid core and a core shell which contain fire-fighting components, and the two components are combined into the fire-fighting sand through high-speed stirring;

The core shell is a hydrophobic particulate material.

2. The fire control sand for cooling the battery according to claim 1, wherein the flame retardant is one or more of ammonium dihydrogen phosphate, ammonium polyphosphate, trimethyl phosphate, dimethyl methylphosphonate, potassium chloride and potassium bicarbonate.

3. The fire control sand for battery cooling according to claim 1, wherein the fluorocarbon surfactant is one or more of 1157, 1470, 1440, 1460, 1183 and 1475.

4. The fire-fighting sand for battery cooling according to claim 1, wherein the nonionic surfactant is one or more of Tween 80, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, BAC-12, CAB-35 and imidazoline.

5. The fire-fighting sand for reducing temperature of a battery according to claim 1, wherein the gel is one or more of gellan gum, xanthan gum, carboxymethyl cellulose, sodium alginate, carrageenan, agar and polyvinyl alcohol.

6. The fire control sand for cooling the battery according to claim 1, wherein the core-shell is one or more of hydrophobic silica, titanium dioxide, aluminum oxide, montmorillonite and bentonite.

7. The fire control sand for cooling batteries according to any one of claims 1 to 7, wherein the mass ratio of the liquid core to the core-shell material is (85-95): 5-15.

8. The method for preparing the fire-fighting sand for cooling the battery according to claim 7, wherein the method comprises the following steps:

9. The preparation method for the fire-fighting sand for battery cooling according to claim 1, wherein the liquid core comprises, by mass, 10-15% of flame retardant, 0.1-2% of fluorocarbon surfactant, 0.1-5% of nonionic surfactant, 1-5% of gelling agent, and the balance deionized water.

10. The method of claim 7, wherein the fire-fighting sand is cooled by a dry powder extinguishing agent nozzle when the environmental temperature of the lithium battery energy storage battery rises rapidly and thermal runaway is about to occur.