A lithium-ion battery thermal runaway gas treatment device

Abstract

The present invention provides a lithium-ion battery thermal runaway gas processing device, including a gas collection module, a gas pretreatment module, and a gas processing module; the gas pretreatment module includes a pretreatment tank and a dilution gas tank; the gas collection module and the dilution gas tank are both connected to the pretreatment tank; the pretreatment tank is connected to the gas processing module; the initial state of the pretreatment tank is a negative pressure state; the connecting pipeline between the pretreatment tank and the dilution gas tank and the gas processing module is connected in series with a valve and a flow meter; the pretreatment tank is also provided with a pressure gauge; the thermal runaway gas is collected through the gas collection module and enters the pretreatment tank, and a cooling unit is also provided in the pretreatment tank. The present invention can collect the thermal runaway gas in the prefabricated cabin in an orderly manner, and transmit it to a safe location outside the prefabricated cabin for safe treatment such as dilution, inerting, cooling, decomposition, conversion, etc., and finally discharge it from the prefabricated cabin. The entire processing process is safe, stable, and efficient, and can avoid the accumulation of thermal runaway gas in the prefabricated cabin and reduce the risk of gas explosion.

Description

Technical Field

[0001] The invention relates to the technical field of lithium ion battery safety, in particular to a lithium ion battery thermal runaway gas treatment device. Background Art

[0002] New energy storage is an important technology and basic equipment for building a new power system, and an important support for achieving the goals of carbon peak and carbon neutrality. Lithium-ion batteries have the characteristics of high energy density, long cycle life, small size and light weight, and green environmental protection, making them the most widely used electrochemical energy storage technology. However, lithium-ion batteries have not yet reached intrinsic safety. Once the battery is in abusive conditions such as short circuit, overheating, and extrusion, the battery may generate a lot of heat, triggering a chain reaction of internal electrolyte and electrode materials, and then thermal runaway. In addition, the working environment of lithium-ion batteries in the energy storage prefabricated cabin is relatively closed, and the number is huge. When lithium-ion batteries have thermal runaway, a large amount of gas will be generated, which is flammable. The gas accumulates in a confined space and mixes with air to form a flammable gas mixture. When its concentration reaches the explosion limit, it is very easy for flammable gas to deflagrate or explode. In addition, thermal runaway gases are also highly toxic. In the energy storage prefabricated cabin, the concentration of flammable, toxic and harmful gases increases sharply, greatly increasing the danger of personnel operation and rescue. At present, when a lithium-ion battery catches fire, the fire extinguishing agent equipped in the energy storage prefabricated cabin can only extinguish the open flame, but does not have the function of rapid and continuous cooling, and cannot effectively block the thermal runaway reaction of the battery. It is easy to re-ignite, and there is a lack of effective prevention and treatment measures for thermal runaway gases. When the open flame is extinguished, there is still a risk of re-ignition and explosion, endangering the lives of operation and maintenance personnel and rescue personnel.

[0003] Therefore, it is necessary to develop a lithium-ion battery thermal runaway gas treatment device to safely and effectively treat the flammable, toxic and harmful gases generated when the battery experiences thermal runaway, reduce the risk of gas explosion, toxicity and pollution, and ensure the safety of relevant personnel.

[0004] For example, a device and method for detecting gas production due to thermal runaway of a lithium-ion battery disclosed in publication number CN11285849A includes: a gas collection tank for collecting gas produced by thermal runaway of a lithium-ion battery; a calorimeter, the calorimeter is connected to the first inlet of the gas collection tank; an inert gas tank, the inert gas tank is connected to the second inlet of the gas collection tank; a gas chromatograph, the first outlet of the gas collection tank is connected to the gas chromatograph; wherein a first airtight valve is provided between the calorimeter and the gas collection tank; a second airtight valve is provided between the inert gas tank and the gas collection tank; and a third airtight valve is provided between the gas collection tank and the gas chromatograph. The present invention can test the composition and proportion of gas produced after thermal runaway of a lithium-ion battery in real time, quickly and accurately by combining the battery calorimeter and the gas chromatograph. The device does not involve the problem of thermal runaway gas explosion, but only detects gas. The inert gas in this scheme is not used to dilute the thermal runaway gas, but 1) as a purge gas for the gas chromatograph to avoid the influence of air on the analysis of the thermal runaway gas composition; 2) as a carrier gas for the thermal runaway gas, it can also help the thermal runaway gas enter the gas chromatograph when there is little thermal runaway gas. In addition, perhaps because of the relationship between gas composition analysis, the inert gas can only be selected as a rare gas such as argon. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to safely, stably and efficiently handle the thermal runaway gas of lithium-ion batteries, avoid the accumulation of thermal runaway gas in the energy storage system or prefabricated cabin, and reduce the risk of gas explosion, toxicity and pollution.

[0006] The present invention solves the above technical problems through the following technical means:

[0007] A lithium-ion battery thermal runaway gas treatment device comprises a gas collection module, a gas pretreatment module, and a gas treatment module; the gas pretreatment module comprises a pretreatment tank and a dilution gas tank; the gas collection module and the dilution gas tank are both connected to the pretreatment tank; the pretreatment tank is connected to the gas treatment module; the initial state of the pretreatment tank is a negative pressure state; a valve and a flow meter are connected in series on the connecting pipeline between the pretreatment tank and the dilution gas tank and the gas treatment module; a pressure gauge is also provided on the pretreatment tank;

[0008] The thermal runaway gas is collected by the gas collection module and enters the pretreatment tank. The dilution gas enters the pretreatment tank from the dilution gas tank and mixes with the thermal runaway gas to inert it. The inerted gas in the pretreatment tank is pumped to the gas module and then restored to the initial negative pressure state. A cooling unit is also provided in the pretreatment tank.

[0009] The beneficial effect of the lithium-ion battery thermal runaway gas treatment device provided by the present invention is that the thermal runaway gas generated by the lithium-ion energy storage batteries at multiple different positions in the prefabricated cabin can be collected in an orderly manner, and transmitted to a safe location outside the prefabricated cabin for safe treatment such as dilution, inerting, cooling, decomposition, conversion, etc., and finally discharged from the prefabricated cabin. The entire treatment process is safe, stable, and efficient, which can avoid the accumulation of thermal runaway gas in the prefabricated cabin, reduce the risk of gas explosion, reduce gas toxicity and pollution, and ensure the personal safety of operation and maintenance and rescue personnel. In particular, the initial state of the pretreatment tank is designed to be a negative pressure state, which can ensure the safety of thermal runaway gas entering the pretreatment tank.

[0010] Furthermore, a first exhaust fan is connected in series between the gas collection module and the gas pre-processing module, and a second exhaust fan is connected in series between the pre-processing module and the gas processing module.

[0011] Furthermore, the valve is a solenoid valve.

[0012] Furthermore, it also includes a control module, and the solenoid valve, flow meter, pressure gauge, first exhaust fan and second exhaust fan are all communicatively connected to the control module.

[0013] Furthermore, the tank wall of the pretreatment tank is corrugated.

[0014] Furthermore, the cooling unit is provided with a cooling layer in the pretreatment tank, and cooling material is placed in the cooling layer.

[0015] Furthermore, the cooling layer is a mesh partition provided in the pretreatment tank, and the mesh partition and the wall of the pretreatment tank are formed to accommodate the cooling material, thereby forming the cooling layer; after the thermal runaway gas enters the pretreatment tank, it passes through the cooling layer and enters the other side of the partition.

[0016] Furthermore, the gas processing module comprises a gas processing tank, in which a filter rack is arranged, and the filter rack is filled with adsorption material.

[0017] Furthermore, the gas collection module includes a gas collection hood and an air guide pipe, and the gas collection hood is connected to the pretreatment module through the air guide pipe; a one-way valve is connected in series to the air guide pipe.

[0018] Furthermore, there are multiple air collecting hoods distributed at different positions in the battery prefabricated cabin.

[0019] The advantages of the present invention are:

[0020] The beneficial effect of the lithium-ion battery thermal runaway gas treatment device provided by the present invention is that the thermal runaway gas generated by the lithium-ion energy storage batteries at multiple different positions in the prefabricated cabin can be collected in an orderly manner, and transmitted to a safe location outside the prefabricated cabin for safe treatment such as dilution, inerting, cooling, decomposition, conversion, etc., and finally discharged from the prefabricated cabin. The entire treatment process is safe, stable, and efficient, which can avoid the accumulation of thermal runaway gas in the prefabricated cabin, reduce the risk of gas explosion, reduce gas toxicity and pollution, and ensure the personal safety of operation and maintenance and rescue personnel. In particular, the initial state of the pretreatment tank is designed to be a negative pressure state, which can ensure the safety of thermal runaway gas entering the pretreatment tank.

[0021] Flow meters, pressure gauges, etc. are used to obtain flow and pressure. The combined control module can automatically control the air intake volume and pressure to ensure the safety of the entire equipment.

[0022] Designing a cooling layer in the pretreatment tank can reduce the temperature of the thermal runaway gas and further ensure the safety of the inerted mixed gas and meet the emission requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the overall structure of a lithium-ion battery thermal runaway gas treatment device provided by an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of the interior of a pretreatment tank of a lithium-ion battery thermal runaway gas treatment device provided by an embodiment of the present invention;

[0025] Figure 3 A top view of a pretreatment tank of a lithium-ion battery thermal runaway gas treatment device provided by an embodiment of the present invention;

[0026] Figure 4 An internal schematic diagram of a gas processing module of a lithium-ion battery thermal runaway gas processing device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] like Figure 1 As shown, this embodiment provides a lithium-ion battery thermal runaway gas processing device, including a detection module 1, a control module 2, a gas collection module, a first exhaust fan 6, a gas pretreatment module, a second exhaust fan 10, and a gas processing module 11.

[0029] The detection module 1 is a plurality of gas detectors located near the lithium-ion energy storage battery in the battery prefabricated cabin. It can collect thermal runaway gases such as carbon monoxide, hydrogen, alkanes and their concentration change signals, and feed them back to the control module 2.

[0030] The detection module 1 may also be equipped with a plurality of temperature detectors, smoke detectors, flame detectors, etc., as long as it can detect thermal runaway of the lithium-ion battery.

[0031] The gas collection module includes a gas collection hood 3, a gas guide duct 4, and a one-way valve 5 arranged on the gas guide duct, which is used to collect the thermal runaway gas and converge it to the gas pretreatment module through the first exhaust fan 6. The gas collection module can collect the thermal runaway gas generated by lithium-ion energy storage batteries at multiple different positions in an orderly manner and transmit it to the gas pretreatment module for dilution and cooling.

[0032] The detection module 1, the control module 2 and the gas collection module are all located in the battery prefabricated cabin.

[0033] The gas pretreatment module includes a dilution gas tank 7 and a pretreatment tank 8, which are located outside the battery prefabricated cabin. The dilution gas tank 7 is connected to the pretreatment tank 8 through a pipeline and an electromagnetic valve 91 on the pipeline. The dilution gas tank 7 is filled with a dilution gas with stable performance, such as nitrogen, argon, carbon dioxide, etc. After the dilution gas is released, the thermal runaway gas in the pretreatment tank 8 is diluted and inerted. Dilution and inerting can reduce the concentration of thermal runaway gas emissions, further reduce gas toxicity and pollution, and improve the safety of thermal runaway gas treatment.

[0034] The pretreatment tank 8 is located between the first exhaust fan 6 and the second exhaust fan 10. A cooling layer is provided inside the pretreatment tank 8 to cool the thermal runaway gas. Figure 2 As shown, the specific structure is that a partition 81 is arranged in the pretreatment tank 8, and a cooling material is filled between the partition 81 and the side wall of the pretreatment tank 8. The thermal runaway gas passes through the partition 81 through the cooling material and enters the other side to mix with the inert gas. The cooling material is one or more of a carbonate compound, a bicarbonate compound, and a crystal water compound. Figure 3 The surface of the pretreatment tank 8 is a staggered concave-convex structure or a fin structure or a serpentine structure, thereby increasing the contact area with the air and the thermal runaway gas, which is conducive to the rapid cooling of the thermal runaway gas. As an important part of the gas pretreatment module, the pretreatment tank 8 can be used as a place for dilution and inerting of the thermal runaway gas on the one hand, and can cool the thermal runaway gas on the other hand. If the pretreatment tank is not set, a large amount of thermal runaway gas generated will rush directly to the gas treatment module through the pipeline or be directly discharged from the prefabricated cabin. The concentration of the thermal runaway gas is relatively high without dilution, and the temperature is relatively high without cooling, which is highly dangerous. If the treatment is not sufficient, the discharged mixed gas may have the risk of combustion and explosion.

[0035] The pretreatment tank 8 is equipped with a pressure gauge to monitor the pressure in the pretreatment tank. When the pretreatment tank is not in working state, it should be in a vacuum negative pressure state.

[0036] The gas outlet pipe of the pretreatment tank 8 is provided with a solenoid valve.

[0037] The capacity and mechanical strength of the dilution gas tank 7 and the pretreatment tank 8 should be selected according to the type, quantity and capacity of the lithium-ion batteries.

[0038] The second exhaust fan 10 transmits the thermal runaway gas after dilution, inerting and cooling to the gas processing module 11 for processing and discharge.

[0039] The gas processing module 11 and the dilution gas tank 7 use a similar cavity, and there is a layer of activated carbon filter frame 111 inside the cavity, refer to Figure 4 The activated carbon filter frame 111 is filled with gas adsorption material, and a layer of breathable film is wrapped outside the activated carbon filter frame 111 to absorb, adsorb, decompose, transform and discharge the thermal runaway gas.

[0040] The gas adsorption material is one or more gas absorbents such as activated carbon, silica gel, zeolite, molecular sieve, activated alumina, porous silica, porous polymer, etc.

[0041] The breathable membrane is one or more of PP membrane, PVDF membrane, ceramic-based carbon nanotube membrane, has good porosity, and has a thickness of 1 to 10 mm. It should ensure a certain mechanical strength and that the thermal runaway gas can pass through the breathable membrane into the adsorption material.

[0042] The gas processing module 11 is equipped with a pressure gauge to monitor the pressure inside the gas processing module.

[0043] The gas outlet pipeline of the gas processing module 11 is provided with a solenoid valve.

[0044] The first exhaust fan 6, the gas pre-processing module, the second exhaust fan 8, and the gas processing module 11 are located outside the battery prefabricated cabin as a whole.

[0045] In this embodiment, in order to ensure the mixing ratio of the thermal runaway gas and the dilution gas, a flow meter can be connected in series to the intake duct and the connecting pipe between the dilution gas and the pretreatment tank to ensure the mixing ratio through flow control to ensure the safety of the mixed gas.

[0046] The working process of a lithium-ion battery thermal runaway gas treatment device of the present invention is as follows:

[0047] The control module 2 receives the signal from the detection module 1, makes a judgment and then feeds back to the first exhaust fan 6, the dilution gas tank 7, and each solenoid valve 91 / 92 / 93. When the control module 2 receives a thermal runaway gas signal or the rate of change of the gas concentration exceeds the set threshold, it is determined that the battery produces thermal runaway gas. The first exhaust fan 6 starts to work, and the thermal runaway gas around the battery is converged to the pretreatment tank 8 of the gas pretreatment module through the gas collecting hood 3, the gas duct 4, and the one-way valve 5, and the solenoid valve 91 of the dilution gas tank duct 7 is opened, and the dilution gas enters the pretreatment tank 8. The control module 2 calculates the mixing ratio of the thermal runaway gas and the dilution gas based on the two flow meters. In the pretreatment tank 8, the thermal runaway gas is in a relatively safe state after being diluted, cooled, and inerted. When the pressure gauge reading of the pretreatment tank 8 reaches the set threshold, the first exhaust fan 6 stops working, the solenoid valve of the dilution gas tank 7 pipeline is closed, the solenoid valve 92 of the pretreatment tank outlet pipeline is opened, and the second exhaust fan 10 starts working to transmit the battery thermal runaway gas to the gas processing module 11 for processing until the pressure of the pretreatment tank reaches the negative pressure value of the initial state, and then the second exhaust fan 10 can be controlled to stop working. During the whole process, the thermal runaway gas will not come into contact with the air, and the safety is high.

[0048] Furthermore, when the thermal runaway gas is processed in the gas processing module 11, the pressure gauge reading of the pretreatment tank 8 continues to decrease, and the pressure gauge reading of the gas processing module 11 continues to increase. When the pressure gauge reading of the pretreatment tank 8 decreases to the set threshold or the pressure gauge reading of the gas processing module 11 increases to the set threshold, the solenoid valve of the outlet pipe of the pretreatment tank 8 is closed, and the first exhaust fan 6 continues to work to collect the thermal runaway gas; the solenoid valve of the dilution gas tank 7 pipeline is opened, and the dilution gas continues to enter the pretreatment tank 8; the second exhaust fan 10 stops working. After the thermal runaway gas is processed in the gas processing module 11 for a period of time, the solenoid valve 93 of the outlet pipe is opened, and the thermal runaway gas is discharged from the battery prefabricated cabin.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lithium-ion battery thermal runaway gas treatment device, characterized in that: It includes a gas collection module, a gas pretreatment module, and a gas treatment module; the gas pretreatment module includes a pretreatment tank and a dilution gas tank; the gas collection module and the dilution gas tank are both connected to the pretreatment tank; the pretreatment tank is connected to the gas treatment module; the initial state of the pretreatment tank is a negative pressure state; a valve and a flow meter are connected in series on the connecting pipeline between the pretreatment tank and the dilution gas tank and the gas treatment module; a pressure gauge is also provided on the pretreatment tank; The thermal runaway gas is collected by the gas collection module and enters the pretreatment tank. The dilution gas enters the pretreatment tank from the dilution gas tank and mixes with the thermal runaway gas to make it inert. The inerted gas in the pretreatment tank is pumped to the gas treatment module and then restored to the initial negative pressure state. A cooling unit is also provided in the pretreatment tank. The cooling unit is a cooling layer provided in the pretreatment tank, and a cooling material is placed in the cooling layer. The cooling layer is a mesh partition provided in the pretreatment tank, and the mesh partition and the tank wall of the pretreatment tank are formed to accommodate the cooling material, thereby forming the cooling layer; after the thermal runaway gas enters the pretreatment tank, it passes through the cooling layer and enters the other side of the partition; the cooling material is one or more of a carbonate compound, a bicarbonate compound, and a crystalline water compound.

2. A lithium-ion battery thermal runaway gas treatment device according to claim 1, characterized in that: A first exhaust fan is connected in series between the gas collection module and the gas pre-processing module, and a second exhaust fan is connected in series between the pre-processing module and the gas processing module.

3. A lithium-ion battery thermal runaway gas treatment device according to claim 2, characterized in that: The valve is a solenoid valve.

4. A lithium-ion battery thermal runaway gas treatment device according to claim 3, characterized in that: It also includes a control module, and the solenoid valve, flow meter, pressure gauge, first exhaust fan and second exhaust fan are all communicatively connected to the control module.

5. A lithium-ion battery thermal runaway gas treatment device according to any one of claims 1 to 4, characterized in that: The tank wall of the pretreatment tank is corrugated.

6. A lithium-ion battery thermal runaway gas treatment device according to any one of claims 1 to 4, characterized in that: The gas processing module comprises a gas processing tank, in which a filter rack is arranged, and the filter rack is filled with adsorption material.

7. A lithium-ion battery thermal runaway gas treatment device according to any one of claims 1 to 4, characterized in that: The gas collection module comprises a gas collection hood and an air guide pipe, and the gas collection hood is connected with the pre-processing module through the air guide pipe; a one-way valve is serially connected to the air guide pipe.

8. A lithium-ion battery thermal runaway gas treatment device according to claim 7, characterized in that: There are multiple air collecting hoods distributed at different positions in the battery prefabricated cabin.

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