Pack-level lithium battery fire extinguishing system

Abstract

The utility model provides a pack-grade lithium battery fire extinguishing system. A compressed air foam generating system is connected with a data acquisition system through an experiment module system; the experiment module system comprises a pack-level experiment box body, a battery, a battery fixing and heating system, a remote control ignition device and a filling mold; the battery, the battery fixing and heating system, the remote control ignition device and the filling mold are all placed in the pack-level experiment box body; the pack-level experiment box body completely simulates the actual situation of an energy storage power station, provides a special experiment platform for pack-level lithium battery fire extinguishing research, and solves the problem of lithium battery fire extinguishing in a limited space; besides, through the synergistic effect of all the systems, the fire behavior characteristics of the lithium battery in the pack-level box body can be accurately and scientifically researched, so that the comprehensive evaluation of the fire extinguishing performance of the lithium battery is realized.

Description

TECHNICAL FIELD

[0001] The utility model belongs to lithium battery fire prevention and control technical field, more specifically, especially relate to a pack level lithium battery fire extinguishing system. BACKGROUND

[0002] Lithium ion batteries have become the most widely used battery type in the field of electrochemical energy storage due to their high charging efficiency, high energy density, long cycle life and green environmental protection characteristics. However, when facing abnormal conditions such as overheating, overcharging and discharging, and short circuit, lithium ion batteries have the risk of thermal runaway, which can release a large amount of heat and toxic gas, and may trigger a fire or even an explosion, posing a serious threat to personnel safety and property safety.

[0003] Currently, dry powder extinguishing agent is used as a means to deal with lithium ion battery thermal runaway, which can effectively suppress the spread of fire, but the problem is that it cannot effectively reduce the temperature inside the lithium battery, so it is easy to reignite after extinguishing, and even may cause another explosion. On the other hand, indiscriminate large-scale spraying of water, heptafluoropropane or perfluoroheptanone extinguishing agent can achieve the effect of cooling and extinguishing, but this method can cause immersion damage to the cells that have not experienced thermal runaway, affecting the overall performance of the battery pack.

[0004] Compressed air foam system is a new extinguishing technology that can quickly extinguish fire, continuously cool and effectively absorb flammable gas, and is considered to have significant advantages in preventing lithium ion battery thermal runaway after reignition, and has been effectively applied in single battery and module level battery thermal runaway, electric vehicle battery fire and other scenarios. However, current research on the behavior characteristics of lithium battery thermal runaway is mostly limited to open space environments, and cannot solve the problem of extinguishing lithium batteries in confined spaces. SUMMARY

[0005] Therefore, the purpose of the utility model is to provide a pack level lithium battery fire extinguishing system for providing a special experimental platform for research on pack level (battery pack level) lithium battery fire extinguishing.

[0006] The application discloses a pack level lithium battery fire extinguishing system, comprising: a compressed air foam generating system, an experimental cabin system and a data acquisition system.

[0007] The compressed air foam generating system is connected to the experimental cabin system and the data acquisition system.

[0008] The experimental cabin system comprises a pack level experimental box, a battery, a battery fixing and heating system, a remote control ignition device, and a filling mold.

[0009] The battery, the battery fixing and heating system, the remote control ignition device and the filling mold are placed in a pack-level experimental box.

[0010] Optionally, the pack-level experimental box is made of steel material.

[0011] One side of the side surface of the pack-level experimental box is provided with three first reserved holes.

[0012] The other side of the side surface of the pack-level experimental box is provided with a fire-fighting water outlet connected with the compressed air foam generating system.

[0013] The bottom surface of the pack-level experimental box is provided with a first liquid discharge port.

[0014] Four casters are installed at the bottom of the pack-level experimental box.

[0015] Optionally, the battery fixing and heating system comprises a metal plate, a heating plate and thermal insulation cotton; wherein the outermost layer is the metal plate, the second outer layer is the thermal insulation cotton; the middle layer is the heating plate and the battery.

[0016] The metal plate is made of steel material.

[0017] The height of the metal plate is consistent with the height of the battery; the width of the metal plate is greater than the width of the battery; after the metal plate and the battery are stacked, two sides of the metal plate which do not overlap with the battery are each provided with three second reserved holes, the second reserved holes are used for penetrating a metal rod, and the metal rod combined with a nut is used for fixing the battery.

[0018] The heating plate and the thermal insulation cotton have the same size as the battery.

[0019] Optionally, the filling mold is a hollow stainless steel structure, the size of the filling mold is consistent with the size of the battery, and the filling mold is used for filling the empty position in the pack-level experimental box.

[0020] Optionally, the remote control ignition device is placed above the safety valve of the battery.

[0021] Optionally, the compressed air foam generating system comprises a gas storage tank, a foam mixture storage tank, a foam mixing chamber, a connecting pipeline and a foam delivery pipeline.

[0022] The gas outlet of the first gas storage tank is connected with the first inlet of the foam mixing chamber through the first connecting pipeline.

[0023] The gas outlet of the second gas storage tank is connected with the inlet of the foam mixture storage tank through the second connecting pipeline.

[0024] The outlet of the foam mixed liquid storage tank is connected with the second inlet of the foam mixing cavity through a third connecting pipeline;

[0025] The outlet of the foam mixing cavity is connected with the fire-fighting water outlet of the experimental cabin system through the foam delivery pipeline.

[0026] Optionally, the compressed air foam generating system further comprises at least one of a pressure reducing valve, a flow meter and a manual valve;

[0027] The pressure reducing valve corresponds to the gas storage tank one by one;

[0028] The pressure reducing valve is arranged on the connecting pipeline connected with the respective gas storage tank;

[0029] The flow meter is arranged on the connecting pipeline connected with the foam mixing cavity;

[0030] The manual valve is arranged on the foam delivery pipeline.

[0031] Optionally, the lower portion of the foam mixed liquid storage tank is provided with a second liquid discharge port.

[0032] Optionally, the data acquisition system comprises a temperature acquisition system, a voltage acquisition system, a gas acquisition system and a foam liquid separation acquisition system;

[0033] The temperature acquisition system comprises a K-type thermocouple;

[0034] The voltage acquisition system comprises a charge-discharge cycle instrument;

[0035] The gas acquisition system comprises a pump suction type gas detector;

[0036] The foam liquid separation acquisition system comprises a beaker and a high-precision balance;

[0037] The beaker is placed on the high-precision balance, and the beaker and the high-precision balance are arranged below the pack level experimental box in the experimental cabin system.

[0038] Optionally, the K-type thermocouple and the charge-discharge cycle instrument are connected with the battery through a first reserved hole in the experimental cabin system.

[0039] From the above technical scheme can know, the utility model provides a kind of pack level lithium battery fire extinguishing system, wherein: compressed air foam generating system is connected with data acquisition system by experiment cabin system;Experiment cabin system includes: pack level experimental box, battery, battery fixation and heating system, remote control ignition device and filling mold;Battery, battery fixation and heating system, remote control ignition device and filling mold are placed in pack level experimental box;The pack level experimental box completely simulates the actual situation of energy storage power station to provide special experimental platform for pack level (battery pack level) lithium battery fire extinguishing research;Solve the problem of lithium battery fire extinguishing in confined space;In addition, through the synergistic effect of each system, the fire behavior characteristics of lithium battery in pack level box can be accurately and scientifically researched, so as to realize the comprehensive evaluation of lithium battery fire extinguishing performance. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, the drawings needed to be used in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without creating labor.

[0041] Figure 1 It is the front view of a kind of pack level lithium battery fire extinguishing system provided by the utility model embodiment;

[0042] Figure 2 It is the plan view of a kind of pack level lithium battery fire extinguishing system provided by the utility model embodiment;

[0043] Figure 3 It is the multi-angle view of the pack level experimental box involved in a kind of pack level lithium battery fire extinguishing system provided by the utility model embodiment;

[0044] Figure 4 It is the schematic diagram of battery fixation and heating system involved in a kind of pack level lithium battery fire extinguishing system provided by the utility model embodiment.

[0045] Reference signs:

[0046] 1-gas storage tank;2-foam mixture storage tank;3-pressure reducing valve;4-flow meter;5-foam mixing cavity;6-connection pipeline;7-foam delivery pipeline;8-hand valve;9-pack level experimental box;10-fire fighting water outlet;11-trolley;12-first liquid discharge port;13-beaker;14-high-precision balance;15-data acquisition system;16-first reserved hole;17-metal plate;18-heat insulation cotton;19-heating plate;20-battery;21-filling mold. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0048] In the present application, the terms "comprising", "containing" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the sentence "including a…" does not exclude the presence of other identical elements in the process, method, article or equipment including the element. In addition, the terms "first", "second", "third", "fourth" and the like (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0049] The embodiments of the present application provide a pack-level lithium battery fire extinguishing system, which is used to solve the problem that the current research on the thermal runaway behavior characteristics of lithium batteries in the prior art is mostly limited to open space environment, and cannot solve the problem of extinguishing lithium battery in a small space.

[0050] Referring to Figure 1 and Figure 2 , the pack-level lithium battery fire extinguishing system comprises a compressed air foam generating system, an experimental cabin system and a data acquisition system 15.

[0051] The compressed air foam generating system is connected with the experimental cabin system and the data acquisition system 15 through the experimental cabin system, and the three systems jointly constitute the core of the entire fire extinguishing system.

[0052] Specifically, the outlet of the compressed air foam generating system is connected with the inlet of the experimental cabin system, so as to ensure that the foam can smoothly enter the experimental cabin; the outlet of the experimental cabin system is connected with the data acquisition system 15, so as to collect and analyze various data in the experimental process in real time.

[0053] The compressed air foam generating system is used to generate air foam and transmit to the experiment cabin system. The experiment cabin system is used to simulate the thermal runaway fire of the pack level lithium battery and the monomer battery and module level battery. The data acquisition system 15 is used to collect the voltage, temperature, gas and foam liquid parameters in the experiment cabin system, and of course other parameters can also be collected.

[0054] As shown in Figure 1 and Figure 3 , the experiment cabin system includes: a pack level experiment box 9, a battery 20, a battery fixing and heating system (not shown), a remote control ignition device (not shown), and a filling mold 21.

[0055] The battery 20, the battery fixing and heating system, the remote control ignition device and the filling mold 21 are placed in the pack level experiment box 9.

[0056] In the pack level experiment box 9, the battery 20 is firmly fixed by the battery fixing and heating system, and the working state of the battery 20 at different temperatures is simulated by the battery fixing and heating system. The remote control ignition device is used to remotely trigger the thermal runaway reaction of the battery 20 when needed to simulate the real fire scene. The filling mold 21 is used to fill the appropriate medium in the experiment cabin to better simulate the fire environment of the lithium battery in actual application.

[0057] In summary, the pack level lithium battery fire extinguishing system realizes effective simulation of lithium battery fire and evaluation of fire extinguishing effect through the close cooperation of the compressed air foam generating system, the experiment cabin system and the data acquisition system 15, which provides strong guarantee for the safe use of lithium batteries.

[0058] In this embodiment, the compressed air foam generating system is connected with the data acquisition system 15 through the experiment cabin system; the experiment cabin system includes: a pack level experiment box 9, a battery 20, a battery fixing and heating system, a remote control ignition device, and a filling mold 21; the battery 20, the battery fixing and heating system, the remote control ignition device and the filling mold 21 are placed in the pack level experiment box 9; the pack level experiment box completely simulates the actual situation of the energy storage power station to provide a special experiment platform for the research of pack level (battery pack level) lithium battery fire extinguishing; solve the problem of lithium battery fire extinguishing in limited space; in addition, through the synergistic effect of each system, the fire behavior characteristics of lithium battery in the pack level box can be accurately and scientifically researched, so as to realize the comprehensive evaluation of the lithium battery fire extinguishing performance.

[0059] Optionally, as shown in Figure 3 , the pack level experiment box 9 is made of steel material, such as carbon steel material, to ensure that the pack level experiment box 9 has excellent durability and protection performance.

[0060] The pack-level experimental enclosure 9 has three first reserved holes 16 on one side. The first reserved holes 16 are used to arrange various circuits. That is, these first reserved holes 16 are specially designed to arrange the circuits required for various experiments, which greatly improves the flexibility and convenience of the experiment.

[0061] The other side of the pack-level experimental chamber 9 is equipped with a fire hydrant 10 that is connected to the compressed air foam generating system.

[0062] Specifically, a fire hydrant 10 is provided on the other side of the pack-level experimental chamber 9, and the fire hydrant 10 is connected to the foam delivery pipe 7. This design not only ensures fire safety during the experiment, but also provides strong support for foam fire extinguishing in emergency situations through the effective connection between the fire hydrant 10 and the foam delivery pipe 7.

[0063] The bottom surface of the pack-grade experimental chamber 9 is provided with a first drain port 12, which is specifically used to drain the foam precipitate, effectively avoiding the accumulation of liquid inside the chamber, thereby maintaining the cleanliness and safety of the experimental environment, and also facilitating the measurement of foam properties such as precipitate time.

[0064] The bottom of the pack-level experimental chamber 9 is equipped with four casters 11. These casters 11 not only facilitate the movement and positioning of the chamber, but also enhance the stability and load-bearing capacity of the chamber to a certain extent.

[0065] like Figure 3 As shown, the specific dimensions of the pack-level experimental chamber 9 are 420mm in length, 700mm in width, and 250mm in height. Its carbon steel plate is 2mm thick, making it sturdy and durable. The chamber includes an upper top plate, a lower bottom plate, and side plates. The lower bottom plate is equipped with a first drain port 12 to facilitate the smooth discharge of foamed liquid.

[0066] During the experiment, a battery 20 with dimensions of 135.3 mm in length, 29.3 mm in width, and 185.3 mm in height can be used. The nominal voltage of the battery 20 is 3.2V and the capacity is 50Ah, which can meet the various requirements of the experiment for the performance testing of the battery 20.

[0067] Optionally, the battery fixing and heating system includes: a metal plate 17, a heating plate 19, and heat insulation cotton 18; wherein the outermost layer is the metal plate 17, the next outermost layer is the heat insulation cotton 18, and the middle layer is the heating plate 19 and the battery 20.

[0068] That is, the battery fixing and heating system is composed of key components such as metal plate 17, heating plate 19 and thermal insulation cotton 18, forming a safe and efficient battery 20 heating and fixing structure. The system adopts a layered design, in which the outermost layer is the metal plate 17, which provides strong protection; the next outer layer is the thermal insulation cotton 18, which effectively isolates heat and prevents energy loss and potential heat risks; the middle layer combines the heating plate 19 and the battery 20, achieving precise heating of the battery 20.

[0069] As shown in the detailed structure, Figure 4 the order of each plate group is as follows: first, a metal plate 17 as a base, then thermal insulation cotton 18, heating plate 19, battery 20, and finally another layer of thermal insulation cotton 18, topped off with another metal plate 17. This layer-by-layer design, through the fastening action of metal rods and nuts, ensures the stable connection of all components, forming a complete battery 20 fixing and heating system.

[0070] The metal plate 17 is made of steel, and the number of metal plates 17 can be 2; the battery fixing and heating system can also include 6 threaded metal rods and 12 nuts.

[0071] The height of the metal plate 17 is consistent with the height of the battery 20 to ensure that the battery 20 can be completely wrapped and fixed.

[0072] The width of the metal plate 17 is greater than the width of the battery 20, and this extra space is used to create a reserved hole for installation and fixation. After the metal plate 17 and the battery 20 are stacked, the two sides of the metal plate 17 that do not overlap with the battery 20 each have three second reserved holes for passing through metal rods, and the metal rods and nuts are used to fix the battery 20.

[0073] The heating plate 19 and the thermal insulation cotton 18 are the same size as the battery 20. This precise size matching not only ensures efficient heat transfer but also maximizes energy efficiency by minimizing heat waste.

[0074] In summary, the battery fixing and heating system provides strong protection for the safe and efficient heating and fixing of the battery 20 with its scientific layered design, precise size matching and strong fixation method.

[0075] Optionally, the filling mold 21 is a hollow stainless steel structure, which not only has excellent durability and corrosion resistance, but also effectively simulates the space occupation of the battery 20 in actual application. The size of the filling mold 21 is consistent with the size of the battery 20, and it is used to fill the empty space in the pack-level experimental box 9; this careful design ensures that they can perfectly fill the empty space in the pack-level experimental box 9, thus building an experimental environment similar to the real battery 20 module.

[0076] Specifically, 51 filling molds 21 can be used to completely fill the experimental pack-level experimental box 9, and the 51 filling molds 21 and the battery 20 are arranged in 4*13, simulating the 4P13S battery 20 module structure. Of course, other arrangement methods can also be used, which will not be described one by one here, and can be determined according to the actual situation, which is within the protection scope of the present application.

[0077] Optionally, the remote control ignition device is placed above the safety valve of the battery 20 to ignite the gas generated after the safety valve of the battery 20 is opened.

[0078] Specifically, after the safety valve of the battery 20 is opened due to overheating or other abnormal conditions, the remote control ignition device can quickly and safely ignite the gas released therefrom. This design not only improves the safety and controllability of the experiment, but also provides researchers with a more intuitive and accurate observation means for the thermal runaway reaction of the battery 20.

[0079] Optionally, the compressed air foam generating system includes a gas storage tank 1, a foam mixture storage tank 2, a foam mixing chamber 5, a connecting pipeline 6, and a foam delivery pipeline 7.

[0080] The gas outlet of the first gas storage tank 1 is connected to the first inlet of the foam mixing chamber 5 through the first connecting pipeline 6.

[0081] The gas outlet of the second gas storage tank 1 is connected to the inlet of the foam mixture storage tank 2 through the second connecting pipeline 6.

[0082] The two gas storage tanks 1 play different roles. The first gas storage tank 1 provides the necessary compressed air for the foam mixing chamber 5. The main role of the second gas storage tank 1 is to inject compressed air into the foam mixture storage tank 2, thereby driving the foam mixture in the tank to flow to the foam mixing chamber 5. In this process, the second gas storage tank 1 actually plays the role of a gas supply part, and the foam mixture storage tank 2 becomes a liquid supply part.

[0083] The outlet of the foam mixture storage tank 2 is connected to the second inlet of the foam mixing chamber 5 through the third connecting pipeline 6, ensuring that the foam mixture can smoothly enter the foam mixing chamber 5 for subsequent mixing and foaming process.

[0084] The outlet of the foam mixing chamber 5 is connected to the fire-fighting water outlet 10 of the experimental cabin system through the foam delivery pipeline 7.

[0085] The foam mixing chamber 5 is the core of the entire compressed air foam generating system, which is responsible for the mixing and foaming of the compressed air from the gas tank 1 and the foam mixture from the foam mixture tank 2. This mixing process not only requires high efficiency, but also needs to ensure that the generated compressed air foam has good stability and fire extinguishing performance.

[0086] Finally, the compressed air foam that has been mixed and foamed sufficiently is delivered to the fire-fighting water outlet 10 of the experimental cabin system through the foam delivery pipeline 7, providing strong support for fire extinguishing operations.

[0087] Optionally, the compressed air foam generating system further comprises at least one of a pressure reducing valve 3, a flow meter 4 and a manual valve 8.

[0088] The pressure reducing valve 3 corresponds to the gas tank 1.

[0089] The pressure reducing valve 3 is arranged on the connecting pipeline 6 connected to the respective gas tank 1; and the pressure reducing valve 3 is directly arranged at the outlet position of the gas tank 1, and its main function is to adjust and reduce the gas pressure released by the gas tank 1 to the outside of the system, to ensure the stability and safety of the system operation.

[0090] The flow meter 4 is arranged on the connecting pipeline 6 connected to the foam mixing chamber 5.

[0091] The flow meter 4 is responsible for monitoring the flow of gas during the mixing process. In order to more accurately control the generation of compressed air foam, two flow meters 4 are used in the system, which are respectively installed on the output pipelines of the gas tank 1 for gas supply and the foam mixture tank 2 for providing foam mixture, so that the output flow of gas and foam mixture can be measured and displayed in real time and accurately, providing strong support for accurate control of the system.

[0092] After the above arrangement is completed, the gas flow and liquid flow provided by the gas tank 1 and the foam mixture tank 2 are adjusted by controlling the pressure reducing valve 3, A-type foam liquid is used, the required compressed air foam flow is set to 100 L / min and the gas-liquid ratio is set to 7:1 by the flow meter 4, to ensure that the compressed air foam is smoothly sprayed through the foam delivery pipeline 7.

[0093] The manual valve 8 is arranged on the foam delivery pipeline 7.

[0094] The manual valve 8 on the foam delivery pipeline 7 is used to connect the experimental cabin system, and the application of compressed air foam is controlled through the manual valve 8.

[0095] In addition, the manual valve 8, as an important control element in the system, is arranged on the foam delivery pipeline 7. This foam delivery pipeline 7 not only undertakes the task of delivering compressed air foam to the designated position, but also is connected to the experimental cabin system through the manual valve 8, so that the operator can flexibly control the application of compressed air foam by opening and closing the manual valve 8, thereby meeting the needs of different experiments or application scenarios.

[0096] Optionally, a second liquid discharge port is arranged below the foam mixture storage tank 2.

[0097] Specifically, the main function of the foam mixture storage tank 2 is to store the foam mixture obtained by mixing the foam liquid and water in different proportions. In order to meet the diversity of foam mixture in actual application, the storage tank can flexibly accommodate mixed liquids of various proportions. In addition, in order to manage and maintain the quality of the foam mixture in the storage tank, especially a liquid discharge port is designed below the storage tank. The design of the second liquid discharge port enables the operator to conveniently discharge the foam mixture that has been stored for a long time and may have deteriorated or no longer meet the use requirements, thereby ensuring that fresh and effective foam mixture is always stored in the storage tank, providing a strong guarantee for the stable operation of the compressed air foam generating system.

[0098] The system precisely controls the gas supply flow and liquid supply flow of the gas storage tank 1 and the foam mixture storage tank 2 by adjusting the pressure reducing valve 3. By using high-quality Class A foam liquid and the precise setting of the flow meter 4, the system can ensure that the flow of compressed air foam reaches 100 L / min, while maintaining the ideal state of the gas-liquid ratio of 7:1, thereby ensuring that the compressed air foam can be smoothly and efficiently sprayed through the foam delivery pipeline 7 to meet the needs of various application scenarios.

[0099] Optionally, the data acquisition system 15 includes a temperature acquisition system, a voltage acquisition system, a gas acquisition system, and a foam liquid separation acquisition system.

[0100] The temperature acquisition system includes a K-type thermocouple. The K-type thermocouple is accurately fixed on the surface of the battery 20 by high-temperature resistant adhesive tape, and can measure and record the temperature changes at different positions on the surface of the battery 20 in real time, providing data support for the in-depth study of the heating behavior of the battery 20.

[0101] The number of thermocouples can be arranged according to different experimental schemes, and the battery 20 can also be set according to different schemes, which is not specifically limited here.

[0102] The voltage acquisition system includes a charge-discharge cycle instrument.

[0103] The charge-discharge cycle instrument is connected with the positive and negative poles of the battery 20 through wires, specifically, the positive pole of the charge-discharge cycle instrument is connected with the positive pole of the battery 20 through wires; the negative pole of the charge-discharge cycle instrument is connected with the negative pole of the battery 20 through wires; the real-time monitoring of the voltage change of the battery 20 is realized, which is helpful to understand the voltage stability and change trend of the battery 20 in the charging and discharging process.

[0104] The gas collection system comprises a pump suction type gas detector.

[0105] The pump suction type gas detector actively sucks air into the inside of the pack level experimental box 9 through the first reserved hole 16, can accurately monitor the change of the gas concentration in the box in real time, and provides an important basis for analyzing the gas composition and concentration change in the battery 20 fire process.

[0106] The foam liquid separation collection system comprises a beaker 13 and a high-precision balance 14.

[0107] The beaker 13 is placed on the high-precision balance 14, and the beaker 13 and the high-precision balance 14 are jointly arranged below the pack level experimental box 9 in the experimental cabin system.

[0108] When the experiment is needed, the first drainage port 12 at the bottom of the pack level experimental box 9 can be opened, and the beaker 13 is accurately placed on the high-precision balance 14 directly below the first drainage port 12, so as to monitor the mass change of the foam liquid in real time, thereby analyzing the extinguishing effect of the foam extinguishing agent on the lithium battery fire.

[0109] Optionally, the K-type thermocouple and the charge-discharge cycle instrument are connected with the battery 20 through the first reserved hole 16 in the experimental cabin system, and are respectively used to monitor the temperature and voltage of the battery 20 in real time, so as to ensure the accuracy and real-time performance of data acquisition.

[0110] The fire extinguishing system provided by the application has high universality and flexibility, is suitable for experimental research of different types of foam and different types of lithium batteries, and can truly restore the extinguishing effect of compressed air foam on lithium battery fire in actual application scenarios. Through comprehensive and accurate research on the fire behavior of lithium batteries in the pack level experimental box 9, the platform fills the gap of the current lithium battery thermal disaster fire extinguishing comprehensive research experimental platform. In the future, we will continuously improve and optimize it, make its function more rich, and design more reasonable, and gradually become a standard experimental platform for lithium battery thermal disaster fire extinguishing research.

[0111] The construction process and experimental steps of the pack level lithium battery fire extinguishing system will be described in detail below, and will be described in combination with related diagrams.

[0112] Firstly, the pack-level experimental box 9 is constructed, which has a specification of 420mm in length, 700mm in width and 250mm in height, is carefully made of carbon steel material with a thickness of 2mm, and contains an upper top plate and a lower bottom plate. In particular, the lower bottom plate is provided with a first liquid discharge port 12. The battery 20 used in the experiment has a size of 135.3mm in length, 29.3mm in width and 185.3mm in height, a nominal voltage of 3.2V, and a capacity of 50Ah. In this experiment, a single battery is used.

[0113] In the experimental preparation stage, the K-type thermocouple is first fixed stably on the surface of the battery 20 by high-temperature-resistant adhesive tape, so as to accurately measure the temperature changes of the battery 20 surface. Subsequently, the charge-discharge cycle instrument is connected to the positive and negative electrodes of the battery 20 through wires, so as to realize real-time tracking of the voltage changes of the battery 20. At the same time, the pump suction type gas detector actively inhales air into the pack-level experimental box 9 through the first reserved hole 16, and monitors the gas concentration fluctuation in the box in real time. In addition, the first liquid discharge port 12 at the bottom of the pack-level experimental box 9 is opened, and the beaker 13 is stably placed on the high-precision balance 14 directly below the first liquid discharge port 12, so as to prepare for subsequent monitoring of the foam liquid separation.

[0114] Next, the metal plate 17, the heat insulation cotton 18, the heating plate 19, the battery 20, the heat insulation cotton 18 and the metal plate 17 are arranged in turn, and the components are firmly fixed using metal rods and nuts. Then, 51 filling molds 21 are used to completely fill the remaining space in the pack-level experimental box 9, which are arranged in a 4*13 manner to simulate a 4P13S battery 20 module. Subsequently, the upper top plate is tightly fixed using screws to ensure the airtightness of the experimental box 9.

[0115] In the experimental system debugging stage, the gas supply flow and liquid supply flow of the gas storage tank 1 and the foam mixed liquid storage tank 2 are controlled by adjusting the pressure reducing valve 3. A class foam liquid is selected, and the flow rate of compressed air foam is set to 100L / min and the gas-liquid ratio is set to 7:1 through the flow meter 4, so as to ensure that the compressed air foam can be smoothly sprayed through the foam delivery pipeline 7. Then, the foam delivery pipeline 7 is connected to the fire water outlet 10 on the pack-level experimental box 9 and is fixed, so as to fully prepare for the start of the experiment.

[0116] When the experiment starts, the thermocouple, the charge-discharge cycle instrument, the pump suction type gas detector and the high-precision balance 14 are turned on at the same time to monitor the surface temperature, voltage, gas concentration in the pack-level experimental box 9 and liquid separation parameters of the battery 20 in real time. Subsequently, the power supply of the heating plate 19 is turned on to continuously heat the battery 20. When the safety valve of the battery 20 is opened, the battery 20 is successfully ignited by remote ignition.

[0117] Subsequently, the compressed air foam generating system was manually started to begin applying Class A foam with a flow rate of 100 L / min and a gas-liquid ratio of 7:1. The foam application was continued until the pack-level experiment box 9 was completely filled, and then the application was stopped. After an interval of 10 minutes, the compressed air foam with the same flow rate and gas-liquid ratio was applied again, and the reburning of the battery 20 was continuously observed.

[0118] During the experiment, key data such as the gas-liquid ratio of the compressed air foam, the discharge flow rate, the discharge time, the extinguishing time, and the temperature, voltage, gas concentration, and liquid separation data during the experiment were recorded in detail. These data will provide valuable basis for subsequent experimental analysis and research.

[0119] In addition, in order to further improve the flexibility and diversity of the experiment, the experiment platform has also been improved in many ways. For example, multiple foam mixture storage tanks 2 are added, each storing a different type of foam mixture, connected to the foam mixture storage tank 2 through a detachable connecting pipeline 6, which allows us to study the effect of different types of foam liquid on the extinguishing effect of the battery 20. At the same time, four casters 11 are installed at the bottom of the pack-level experiment box 9, which greatly facilitates the movement of the experimental device and the replacement of the experimental scene. In addition, the probe of the pump suction gas detector can also be replaced to measure the concentration changes of multiple gases including CO, CO2, H2, EX, HF, etc., thereby more comprehensively collecting gas information during the battery 20 combustion process. Finally, the combination of the first liquid outlet 12, the beaker 13, and the high-precision balance 14 is used to accurately monitor the liquid separation of the compressed air foam during the entire experiment.

[0120] In summary, the experiment platform of the present embodiment successfully constructs a pack-level lithium battery fire extinguishing experiment platform based on compressed air foam by skillfully combining the compressed air foam generating system, the experiment cabin system, and the data acquisition system 15. This platform will provide strong support for our in-depth study of the fire extinguishing mechanism of lithium battery fires.

[0121] The features described in the various embodiments in the specification can be substituted or combined with each other, and the same or similar parts among the various embodiments can be referred to each other, and each embodiment focuses on the difference from other embodiments. Especially, for the system or system embodiments, since they are basically similar to the method embodiments, they are described more simply, and the relevant parts can be referred to the part of the method embodiments. The above described system and system embodiments are only illustrative, and the units described as separate components can be or can not be physically separated, and the components shown as units can be or can not be physical units, i.e. they can be located in one place or distributed to multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiments according to the actual needs. Those skilled in the art can understand and implement without creative labor.

[0122] The skilled person can further realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized in electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been described in the above description in general terms. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0123] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pack-level lithium battery fire suppression system, characterized in that, The utility model relates to a kind of experimental device, including: compressed air foam generating system, experimental cabin system and data acquisition system (15); The compressed air foam generating system is connected with the data acquisition system (15) by the experimental cabin system; The experimental cabin system includes: pack level experimental box (9), battery (20), battery fixation and heating system, remote control ignition device and filling mold (21); The battery (20), the battery fixation and heating system, the remote control ignition device and the filling mold (21) are placed in the pack level experimental box (9).

2. The pack-level lithium battery fire suppression system of claim 1, wherein, The pack level experimental box (9) is made of steel; One side of the side of the pack level experimental box (9) is provided with three first reserved holes (16); The other side of the side of the pack level experimental box (9) is provided with a fire water outlet (10) connected with the compressed air foam generating system; The bottom of the pack level experimental box (9) is provided with a first liquid discharge port (12); Four casters (11) are installed on the bottom of the pack level experimental box (9).

3. The pack-level lithium battery fire suppression system of claim 1, wherein, The battery fixation and heating system includes: metal plate (17), heating plate (19) and heat insulation cotton (18);The outermost layer is metal plate (17), the second outer layer is heat insulation cotton (18);The middle layer is heating plate (19) and battery (20); The metal plate (17) is made of steel; The height of the metal plate (17) is consistent with the height of the battery (20);The width of the metal plate (17) is greater than the width of the battery (20), and the two sides of the metal plate (17) not overlapping with the battery (20) after stacking the metal plate (17) and the battery (20) are each provided with three second reserved holes, and the second reserved holes are used for penetrating metal rods, and the metal rods are combined with nuts to fix the battery (20); The size of the heating plate (19) and the heat insulation cotton (18) is consistent with the size of the battery (20).

4. The pack-level lithium battery fire suppression system of claim 1, wherein, The filling mold (21) is a hollow stainless steel structure, and the size of the filling mold (21) is consistent with the size of the battery (20), which is used to fill the empty position in the pack level experimental box (9).

5. The pack-level lithium battery fire suppression system of claim 1, wherein, The remote control ignition device is placed above the safety valve of the battery (20).

6. The pack-level lithium battery fire suppression system of claim 1, wherein, The compressed air foam generating system includes: gas storage tank (1), foam mixture storage tank (2), foam mixing chamber (5), connecting pipeline (6) and foam delivery pipeline (7); The gas outlet of the first gas storage tank (1) is connected with the first inlet of the foam mixing chamber (5) through the first connecting pipeline (6); The gas outlet of the second gas storage tank (1) is connected with the inlet of the foam mixture storage tank (2) through the second connecting pipeline (6); The outlet of the foam mixture storage tank (2) is connected with the second inlet of the foam mixing chamber (5) through the third connecting pipeline (6); The outlet of the foam mixing chamber (5) is connected with the fire water outlet (10) of the experimental cabin system through the foam delivery pipeline (7).

7. The pack-level lithium battery fire suppression system of claim 6, wherein, The compressed air foam generating system further comprises at least one of a pressure reducing valve (3), a flow meter (4) and a manual valve (8); The pressure reducing valve (3) corresponds to the air tank (1) one by one; The pressure reducing valve (3) is arranged on the connecting pipeline (6) connected with the air tank (1); The flow meter (4) is arranged on the connecting pipeline (6) connected with the foam mixing cavity (5); The manual valve (8) is arranged on the foam delivery pipeline (7).

8. The pack-level lithium battery fire suppression system of claim 6, wherein, A second liquid discharge port is arranged below the foam mixed liquid tank (2).

9. The pack-level lithium battery fire suppression system of claim 1, wherein, The data acquisition system (15) comprises a temperature acquisition system, a voltage acquisition system, a gas acquisition system and a foam liquid separation acquisition system; The temperature acquisition system comprises a K-type thermocouple; The voltage acquisition system comprises a charge-discharge cycle instrument; The gas acquisition system comprises a pump suction type gas detector; The foam liquid separation acquisition system comprises a beaker (13) and a high-precision balance (14); The beaker (13) is placed on the high-precision balance (14), and the beaker (13) and the high-precision balance (14) are arranged below the pack level experimental box (9) in the experimental cabin system.

10. The pack-level lithium battery fire suppression system of claim 9, wherein, The K-type thermocouple and the charge-discharge cycle instrument are connected with the battery (20) through the first reserved hole (16) in the experimental cabin system.

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