Thermal runaway flue gas treatment device and energy storage equipment

Abstract

The invention provides a thermal runaway flue gas treatment device and energy storage equipment, and mainly solves the problem of potential safety hazards caused by thermal runaway of an existing lithium battery. A liquid treatment tank of the thermal runaway flue gas treatment device is connected with a liquid inlet pipeline, the liquid inlet pipeline is used for introducing external water into the liquid treatment tank, and solid alkali in the liquid treatment tank is dissolved by water to form an alkali solution. When the battery works normally, only solid alkali is placed in the liquid treatment tank, the requirement of the solid alkali on the material of the liquid treatment tank is not high, so that the manufacturing cost of the device is relatively low, meanwhile, only solid alkali is placed in the liquid treatment tank, the weight of the whole liquid treatment tank is small, and the liquid treatment tank is very convenient to mount and dismount. When the thermal runaway of the battery occurs, the liquid inlet pipeline introduces external water into the liquid treatment tank to form an alkali solution, and the alkali solution effectively treats the thermal runaway flue gas.

Description

Technical Field

[0001] The present invention belongs to the field of batteries, and in particular relates to a thermal runaway flue gas treatment device and an energy storage device. Background Art

[0002] With the development of new energy sources such as solar energy and wind energy, energy storage technology has also developed. Lithium batteries have gradually become the mainstream product for energy storage due to their high energy, long service life, high rated voltage, high power tolerance, and low self-discharge rate.

[0003] With the large-scale application of lithium battery energy storage systems, the safe use of lithium-ion batteries has also attracted attention. Due to the high concentration of battery modules in energy storage equipment, under the influence of factors such as battery overcharge, overdischarge, overheating, and mechanical collision, it is easy to cause battery diaphragm collapse and internal short circuit, thus leading to thermal runaway.

[0004] When a lithium battery is in complete thermal runaway, the internal temperature of the battery is as high as 500-1000℃. The gas generated during the thermal runaway process causes the internal pressure of the battery to increase, causing the battery shell to expand and rupture, and eventually the explosion venting membrane opens, spraying and releasing the evaporated electrolyte and reaction gas inside the battery, forming thermal runaway smoke. The thermal runaway smoke includes combustibles such as electrolyte, hydrogen, carbon monoxide, methane, and ethylene, and combustibles account for a large proportion of the thermal runaway smoke. When the thermal runaway smoke is discharged from the battery shell, the combustibles come into contact with the air and are prone to combustion. In severe cases, they can cause explosions, posing safety hazards. Summary of the invention

[0005] In order to solve the problem of potential safety hazards caused by thermal runaway of existing lithium batteries, the present invention provides a thermal runaway flue gas treatment device and an energy storage device.

[0006] To achieve the above object, the technical solution of the present invention is:

[0007] A thermal runaway flue gas treatment device comprises at least one liquid treatment tank; the liquid treatment tank is provided with a flue gas inlet and a flue gas outlet connected to its inner cavity, and the liquid treatment tank is filled with solid alkali; the liquid treatment tank is connected with a liquid inlet pipeline, which is used to introduce external water into the liquid treatment tank, and the solid alkali in the liquid treatment tank is dissolved by water to form an alkaline solution, and the alkaline solution is used to treat the thermal runaway flue gas.

[0008] Furthermore, a control valve and a flow meter are provided on the liquid inlet pipeline.

[0009] Furthermore, the solid alkali is solid sodium hydroxide, and the ratio of solid sodium hydroxide to water is 2g-10g of solid sodium hydroxide dissolved in 1L of water.

[0010] Furthermore, the flue gas inlet and the flue gas outlet are both arranged at the top of the liquid treatment tank, the flue gas inlet is connected to a smoke inlet pipeline, at least a portion of the smoke inlet pipeline can be immersed in the alkaline solution, and a diversion part is arranged at the end of the smoke inlet pipeline immersed in the alkaline solution.

[0011] Furthermore, a spiral baffle is provided on the smoke inlet pipeline or a plurality of baffles are provided on the smoke inlet pipeline to increase the distance traveled by the thermal runaway flue gas in the liquid treatment tank.

[0012] Furthermore, there are multiple liquid treatment tanks, and a three-way valve is provided on the smoke outlet of each liquid treatment tank. The first port of the three-way valve is connected to the inner cavity of the liquid treatment tank, the second port is used to discharge the thermal runaway smoke, and the third port is connected to the liquid inlet pipeline, and each liquid inlet pipeline is connected to the manifold.

[0013] Furthermore, there are multiple liquid processing tanks, and the liquid inlet pipeline of each liquid processing tank is arranged on the side wall of the tank body of the liquid processing tank, and each liquid inlet pipeline is connected to the manifold.

[0014] The present invention also provides an energy storage device, which includes multiple battery modules, a temperature control system, a fire protection system and the thermal runaway flue gas treatment device described in any of the above items.

[0015] Furthermore, the liquid inlet pipeline is connected to the fire-fighting pipeline of the fire-fighting system, and the liquid inlet pipeline introduces the fire-fighting water in the fire-fighting pipeline into the liquid treatment tank, and the solid alkali in the liquid treatment tank is dissolved by the fire-fighting water to form an alkaline solution.

[0016] Furthermore, the liquid inlet pipeline is connected to the temperature control pipeline of the temperature control system, and the liquid inlet pipeline introduces the cooling water in the temperature control pipeline into the liquid treatment tank, and the solid alkali in the liquid treatment tank is dissolved by the cooling water to form an alkali solution.

[0017] Furthermore, the liquid inlet pipeline is used to be connected to the liquid inlet pipeline in the temperature control pipeline.

[0018] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0019] 1. The thermal runaway flue gas treatment device provided by the present invention has a liquid inlet pipeline reserved on the liquid treatment tank. The liquid inlet pipeline is used to introduce external water into the liquid treatment tank before the battery is about to have thermal runaway. The solid alkali in the liquid treatment tank is dissolved by the external water to form an alkaline solution, and the alkaline solution treats the thermal runaway flue gas. When the battery is working normally, only solid alkali is placed in the liquid treatment tank, and the corrosive damage of the solid alkali to the liquid treatment tank is relatively small. Therefore, the material requirements of the liquid treatment tank are not high, and the production cost of the thermal runaway flue gas treatment device is relatively low. At the same time, since only solid alkali is placed in the liquid treatment tank, the weight of the entire liquid treatment tank is small, and the liquid treatment tank is very easy to install and disassemble when the energy storage device is assembled and repaired. When the battery is about to have thermal runaway, the liquid inlet pipeline will introduce external water into the liquid treatment tank to form an alkaline solution. At this time, the alkaline solution formed will not precipitate or the like, and the treatment effect on the thermal runaway flue gas is better.

[0020] 2. In the thermal runaway flue gas treatment device of the present invention, a control valve is arranged on the liquid inlet pipeline. When the battery is in thermal runaway, the control valve is opened to immediately connect the liquid inlet pipeline with the external pipeline filled with water, and timely introduce the water in the external pipeline into the liquid treatment tank to form an alkaline solution, thereby being able to timely treat the thermal runaway flue gas. At the same time, a flow meter is also arranged on the liquid inlet pipeline, and the flow meter is used to control the volume of water entering the liquid treatment tank, so that an alkaline solution of 0.05 to 0.5 mol / L is formed in the liquid treatment tank. The alkaline solution of this concentration has a more prominent effect on the treatment of thermal runaway flue gas.

[0021] 3. In the thermal runaway flue gas treatment device of the present invention, the solid alkali is solid sodium hydroxide, which is dissolved by external water to form a NaOH solution. The NaOH solution can not only fully treat the electrolyte carried in the thermal runaway flue gas to prevent the vaporized electrolyte from continuing to decompose and produce combustible gas, but also treat part of the gas in the thermal runaway flue gas. The gas volume of the thermal runaway flue gas treated with the NaOH solution is greatly reduced.

[0022] 4. In the thermal runaway flue gas treatment device of the present invention, the flue gas inlet and the flue gas outlet on the liquid treatment tank are both arranged at the top of the liquid treatment tank, which improves the connectivity of the entire thermal runaway flue gas treatment device and the compactness of the pipeline layout. At the same time, a smoke inlet pipeline is arranged in the liquid treatment tank, and at least part of the smoke inlet pipeline can be immersed in the alkaline solution, so that the thermal runaway flue gas can fully contact with the alkaline solution. At the same time, a diversion part is arranged at one end of the smoke inlet pipeline immersed in the alkaline solution. When the thermal runaway flue gas passes through the liquid treatment tank, the diversion part breaks up and diverts the thermal runaway flue gas and then reacts with the alkaline solution in the liquid treatment tank, so that the thermal runaway flue gas can be more fully contacted with the alkaline solution for reaction, thereby improving the treatment effect of the alkaline solution and treating the thermal runaway flue gas more thoroughly.

[0023] 5. In the thermal runaway flue gas treatment device of the present invention, a spiral baffle or multiple baffles are arranged on the smoke inlet pipe. When the thermal runaway flue gas passes through the liquid treatment tank, the spiral baffle or multiple baffles increase the stroke of the thermal runaway flue gas, so that the thermal runaway flue gas can more fully contact and react with the alkaline solution, further improving the treatment effect of the alkaline solution.

[0024] 6. In the thermal runaway flue gas treatment device of the present invention, the liquid treatment tank is connected to the liquid inlet pipeline through a three-way valve. This method does not require any structural changes to the existing liquid treatment tank. It only requires the installation of a three-way valve on the flue gas outlet, which can reduce the production cost of the liquid treatment tank.

[0025] 7. In the thermal runaway flue gas treatment device of the present invention, the liquid inlet pipeline is used to connect with the fire-fighting pipeline or the temperature control pipeline, and then the fire-fighting water and cooling water in the fire-fighting pipeline or the temperature control pipeline are introduced into the liquid treatment tank to form an alkaline solution. The fire-fighting pipeline or the temperature control pipeline is the original pipeline in the energy storage device or the energy storage device use site. The liquid inlet pipeline is connected with the fire-fighting pipeline or the temperature control pipeline, and there is no need to set up an additional liquid inlet pipeline. The connection of the entire pipeline is more convenient, and the production cost of the energy storage device is further reduced.

[0026] 8. In the thermal runaway flue gas treatment device of the present invention, the liquid inlet pipeline is connected to the liquid inlet pipeline in the temperature control pipeline. The cooling water in the liquid inlet pipeline has a lower temperature after cooling. After it is introduced into the liquid treatment tank to form an alkaline solution, the temperature of the alkaline solution is also relatively low. The alkaline solution with a lower temperature can cool the thermal runaway flue gas better, so that the temperature of the treated thermal runaway flue gas is lower, reducing the possibility of combustion after it is discharged.

[0027] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the structure of the thermal runaway flue gas treatment device in Example 1;

[0030] Figure 2 It is an exploded view of the thermal runaway flue gas treatment device in Example 1;

[0031] Figure 3It is a cross-sectional view of the liquid treatment tank (liquid inlet pipeline omitted) in Example 1;

[0032] Figure 4 is a cross-sectional view of the liquid treatment tank (including the spiral baffle) in Example 1;

[0033] Figure 5 is a cross-sectional view of the liquid treatment tank (including baffles) in Example 1;

[0034] Figure 6 This is a schematic diagram of the structure of the thermal runaway flue gas treatment device in Example 2.

[0035] Figure markings: 1-liquid treatment tank, 2-control valve, 3-flow meter, 4-manifold, 5-three-way valve, 11-smoke inlet, 12-smoke outlet, 13-liquid inlet pipeline, 14-connecting pipeline, 15-smoke inlet pipeline, 16-diversion part, 17-spiral baffle, 18-baffle. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0037] The "other embodiments" that appear in different places in this specification do not all refer to the same embodiment, nor are they separate or selective embodiments that are mutually exclusive with other embodiments. In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically limited.

[0038] In the description of this specification, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate, or the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] At the same time, in the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "top, bottom, inside and outside" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0040] Existing energy storage equipment is mainly composed of energy storage box, battery cluster, battery management system (BMS), temperature control system and fire protection system. The battery cluster includes multiple batteries, each of which is closely arranged in the energy storage box. Due to the high concentration of batteries in the energy storage box, under the influence of factors such as battery overcharge, overdischarge, overheating, and mechanical collision, it is easy to cause battery diaphragm collapse and internal short circuit, thus leading to thermal runaway.

[0041] Research shows that when a lithium-ion battery experiences thermal runaway, a series of chemical reactions will occur inside, releasing a large amount of heat and gas, such as: SEI film decomposition reaction (90-120°C), cathode and electrolyte reaction (100-350°C), electrolyte decomposition reaction (110-300°C), diaphragm shrinkage and melting reaction (>130°C), cathode and electrolyte reaction (200-300°C), and binder decomposition reaction (200-300°C), etc. The above reactions do not occur in a fixed order, nor do they proceed independently.

[0042] The thermal runaway flue gas discharged by lithium-ion batteries mainly includes the following components: vaporized electrolyte, CO2, CO, H2, C x H y , C x H y O z , C x H y F, POF3 and HF, etc. The thermal runaway flue gas contains not only hydrogen, CO, CO2, methane and other gases, but also a large amount of electrolyte vapor. The vaporized electrolyte will not only react with the positive or negative electrode in the battery cavity, but will also undergo a series of decomposition reactions, and then continue to produce a large amount of harmful gases and combustible gases. After the thermal runaway flue gas is discharged, it is easy to burn when it comes into contact with air, and in severe cases, it will cause an explosion, posing a safety hazard.

[0043] Based on this, the present invention provides a thermal runaway flue gas treatment device, which includes at least one liquid treatment tank. When the battery is working normally, there is only solid alkali in the liquid treatment tank, and the solid alkali has little corrosive damage to the liquid treatment tank. Therefore, the material requirements for the liquid treatment tank are not high, so the production cost of the liquid treatment tank is relatively low. At the same time, since only solid alkali is placed in the liquid treatment tank, the weight of the entire liquid treatment tank is relatively small. When the energy storage device is assembled and repaired, the liquid treatment tank with a small weight is very convenient for installation and disassembly. When the battery is about to have a thermal runaway, the liquid inlet pipeline will introduce external water into the liquid treatment tank to dissolve the solid alkali to form an alkaline solution. At this time, the alkaline solution formed will not precipitate, etc., and can fully treat the electrolyte and gas in the thermal runaway flue gas, and the treatment effect of the thermal runaway flue gas is better.

[0044] In addition, the present invention can also have another implementation method: the liquid treatment tank of the thermal runaway flue gas treatment device directly stores an alkaline solution, and the alkaline solution treats the thermal runaway flue gas generated by the thermal runaway battery to reduce the harmfulness of the discharged thermal runaway flue gas. However, compared with the above method, this method has the following defects:

[0045] First, the possibility of thermal runaway of the battery module in the energy storage device is very small. Most of the thermal runaway flue gas treatment devices do not work during the entire service life of the energy storage device. The above-mentioned alkaline solution is corrosive to the liquid treatment tank when stored in the liquid treatment tank for a long time. At this time, the liquid treatment tank needs to be made of anti-corrosion materials, which increases the production cost of the thermal runaway flue gas treatment device.

[0046] Second, after the alkaline solution is placed in the liquid treatment tank for a long time, precipitation and other phenomena will occur, which will affect the treatment effect of thermal runaway flue gas;

[0047] Third, the liquid treatment tank storing the alkaline solution is heavy, which is very inconvenient to operate during the installation and maintenance of the energy storage equipment.

[0048] Example 1

[0049] like Figure 1 and Figure 2 As shown, the thermal runaway flue gas treatment device provided in this embodiment includes at least one liquid treatment tank 1, and the liquid treatment tank 1 is provided with a flue gas inlet 11 and a flue gas outlet 12 connected with its inner cavity, and the liquid treatment tank 1 is filled with solid alkali; at the same time, the liquid treatment tank 1 is connected with a liquid inlet pipeline 13, and the liquid inlet pipeline 13 introduces external water into the liquid treatment tank 1 when the battery is about to have thermal runaway, and the solid alkali in the liquid treatment tank 1 is dissolved by the external water to form an alkaline solution, and the alkaline solution treats the thermal runaway flue gas generated by the thermal runaway battery.

[0050] In the above-mentioned thermal runaway flue gas treatment device, the number of liquid treatment tanks 1 can be set according to the number and demand of batteries. If there are multiple liquid treatment tanks 1, multiple liquid treatment tanks 1 can be connected in series through the connecting pipe 14. The shape of the liquid treatment tank 1 is not limited, and can be a rectangular tank body, a circular tank body, an elliptical tank body, etc. A circular tank body is preferably used, and a circular tank body has good pressure bearing performance.

[0051] like Figure 1 and Figure 2 As shown, the liquid treatment tank 1 is provided with a smoke inlet 11 and a smoke outlet 12. The smoke inlet 11 is used to input the thermal runaway smoke into the liquid treatment tank 1, and the smoke outlet 12 is used to discharge the treated thermal runaway smoke. When the smoke inlet 11 is specifically set, it can be set at the top of the liquid treatment tank 1, or it can be set at the bottom of the liquid treatment tank 1. In order to facilitate the connection of each liquid treatment tank 1, it is preferred to set the smoke inlet 11 and the smoke outlet 12 at the top of the liquid treatment tank 1. At this time, each liquid treatment tank 1 only needs to be connected at the top, which improves the connectivity of the entire thermal runaway smoke treatment device and the compactness of the pipeline layout. In addition, the above-mentioned connecting pipeline 14 can adopt a metal bellows. After the metal bellows are connected, each liquid treatment tank 1 can be arranged according to the requirements of the installation space to meet various installation requirements and save installation space.

[0052] like Figure 1 and Figure 2 As shown, the liquid inlet pipeline 13 in this embodiment is specifically connected to the liquid treatment tank 1 through a three-way valve 5. When specifically connected, a three-way valve 5 is installed on the smoke outlet 12 of each liquid treatment tank 1. The three-way valve 5 can specifically be a three-way ball valve, etc. The first port of the three-way valve 5 is connected to the inner cavity of the liquid treatment tank 1, the second port is used to discharge the thermal runaway smoke, and the third port is connected to the liquid inlet pipeline 13. If there are multiple liquid treatment tanks 1, the liquid inlet pipeline 13 of each liquid treatment tank 1 is connected to the manifold 4, and the same transportation of external water is achieved through the manifold 4. The liquid treatment tank 1 in this embodiment is connected to the liquid inlet pipeline 13 through the three-way valve 5. This connection method does not require structural changes to the existing liquid treatment tank 1. It only needs to install the three-way valve 5 on the smoke outlet 12 of the existing liquid treatment tank and connect the liquid inlet pipeline 13 to the three-way valve 5. This connection method can reduce the manufacturing cost of the liquid treatment tank.

[0053] The liquid inlet pipeline 13 in this embodiment is used to connect with the fire-fighting pipeline. When the battery is about to have thermal runaway, the fire-fighting water in the fire-fighting pipeline is introduced into the liquid treatment tank 1. At this time, the solid alkali in the liquid treatment tank 1 is dissolved by the fire-fighting water to form an alkaline solution. The alkaline solution treats the electrolyte and part of the gas carried in the thermal runaway flue gas generated by the thermal runaway of the battery to prevent the vaporized electrolyte from continuing to decompose and produce combustible gas, thereby reducing the content of combustibles (electrolyte and combustible gas) in the thermal runaway flue gas, so as to achieve effective treatment of the thermal runaway flue gas and reduce the hazards caused by its discharge.

[0054] The fire-fighting pipeline can be a fire-fighting pipeline used for fire extinguishing in the energy storage device, or a fire-fighting pipeline at the site where the energy storage device is used. The fire-fighting pipeline is connected to a fire-fighting pool or a fire hydrant so that the fire-fighting pipeline is filled with water.

[0055] After the fire-fighting pipeline and the liquid inlet pipeline 13 are connected, an internal control valve 2 needs to be installed on the fire-fighting pipeline or the liquid inlet pipeline 13. The control valve 2 is a normally closed valve. When the battery is working normally, the fire-fighting water in the fire-fighting pipeline and the liquid inlet pipeline 13 is disconnected by the control valve. When the battery is about to have thermal runaway, the control valve 2 is opened, and the water in the fire-fighting pipeline enters the liquid treatment tank 1 through the liquid inlet pipeline 13. At this time, the solid alkali dissolves in the water to form an alkaline solution.

[0056] The opening requirements of the above-mentioned control valve 2 are as follows: when the battery is about to have thermal runaway, or when thermal runaway has occurred, the control valve 2 is opened. The control valve 2 generally adopts an automatic control valve, which is mainly opened by sensors in the BMS system or energy storage equipment. When it is opened by the BMS system, the BMS monitors the voltage, current and temperature of the battery in the energy storage device in real time. When the voltage, current and temperature of the battery exceed the threshold, the control valve 2 opens. When opened by the sensor, the sensor is a sensor for detecting temperature, pressure, and gas, such as a pressure sensor, a temperature sensor or a smoke sensor, etc. The above-mentioned sensor is arranged in the energy storage box or in the battery module to monitor the temperature, pressure, combustible gas, etc. in real time. When the value monitored by the sensor exceeds the threshold, the control valve 2 opens.

[0057] In addition, when the control valve 2 is installed, it is better to install it on the liquid inlet pipeline 13. When the battery has thermal runaway, since the fire pipeline is full of fire water, the control valve 2 can immediately introduce the fire water in the fire pipeline into the liquid treatment tank 1 to form an alkaline solution, so that the thermal runaway flue gas can be treated in time. If the control valve 2 is installed on the fire pipeline, after the control valve 2 is opened, the water in the fire pipeline may need to pass through a section of the empty pipeline of the fire pipeline before entering the liquid treatment tank 1. There will be a certain time delay for the water in the fire pipeline to enter the liquid treatment tank 1, and there may be a risk of untimely treatment of the thermal runaway flue gas.

[0058] After the fire water in the above-mentioned fire-fighting pipeline is introduced into the liquid treatment tank 1, the liquid treatment tank 1 is filled with solid alkali, and the fire-fighting water dissolves the solid alkali to form an alkaline solution. The solid alkali is generally solid sodium hydroxide, solid potassium hydroxide, solid barium hydroxide, etc., which, after being dissolved in the fire-fighting water, forms alkaline solutions such as sodium hydroxide solution, potassium hydroxide solution, and barium hydroxide solution. The above alkaline solution can not only react with carbonate substances in the electrolyte, prevent the already vaporized electrolyte from continuing to produce harmful gases and combustible gases, but also treat the thermal runaway flue gas to a certain extent at the source. The alkaline solution also has a good treatment effect on acidic substances such as CO2, POF3 and HF, and can effectively treat some gases in the thermal runaway flue gas. In addition, the alkaline solution can also cool the thermal runaway flue gas to reduce the possibility of combustion after it is discharged.

[0059] For alkaline solutions, generally, the higher the concentration, the better the treatment effect on thermal runaway flue gas. However, the applicant found that low-concentration alkaline solutions have better treatment effects than high-concentration alkaline solutions, especially 0.05-0.5 mol / L alkaline solutions. When thermal runaway flue gas passes through an alkaline solution of this concentration, the amount of gas collected is minimal, and its treatment effect is better than that of alkaline solutions with a concentration of more than 0.5 mol / L. Therefore, the prejudice of the prior art is overcome, and a low-concentration alkaline solution is used to treat thermal runaway flue gas, so that the alkaline solution can achieve more effective treatment of thermal runaway flue gas.

[0060] Taking the alkaline solution as NaOH solution as an example, a large number of battery thermal runaway tests were carried out. After a horizontal comparison of the treatment effects of water and NaOH solutions of different concentrations on thermal runaway flue gas, it was found that the volume of gas collected after the thermal runaway flue gas was the smallest after being treated with 0.05-0.5 mol / L NaOH solution, the effect was significant after being treated with 0.1-0.2 mol / L NaOH solution, and the best effect was achieved after being treated with 0.1 mol / L NaOH solution.

[0061] Table 1 Unprocessed full-charge 32650 battery out-of-control data

[0062]

[0063] Table 2 Treatment results of different concentrations of NaOH solution

[0064]

[0065]

[0066] When the thermal runaway flue gas is transported to the NaOH solution, the NaOH solution reacts with the electrolyte, CO2, POF3 and acidic substances such as HF in the thermal runaway flue gas. For example, the ester in the electrolyte reacts with the NaOH solution: CHOOCR+NaOH=RCOONa+CHOH; CO2 reacts with the NaOH solution: 2NaOH+CO2=Na2CO3+H2O; CO2 will also react subsequently: Na2CO3+CO2+H2O=2NaHCO3; POF3 reacts with the NaOH solution: POF3+2NaOH=NaPF2O2+NaF+H2O; HF reacts with the NaOH solution: NaOH+HF=NaF+H2O. After the above reactions, the volume of the thermal runaway flue gas is greatly reduced.

[0067] According to the above test data, when the thermal runaway flue gas of the fully charged 32650 battery after thermal runaway is not treated in any way, the collected gas volume is 4L. When the thermal runaway flue gas of the fully charged 32650 battery after thermal runaway passes through a NaOH solution with a concentration of 0.5mol / L or more, the collected gas is generally greater than 2L, and the treatment effect is not ideal. After the thermal runaway flue gas of the fully charged 32650 battery after thermal runaway passes through a 0.05-0.5mol / L NaOH solution, the gas volume is small, all below 2L. After being treated with 0.1-0.2mol / L sodium hydroxide, the effect is significant. After being treated with 0.1mol / L sodium hydroxide, the collected gas volume is the smallest, only about 1L, and the effect is the best. Therefore, 0.05-0.5mol / L NaOH solution has a good treatment effect on the thermal runaway flue gas after battery thermal runaway.

[0068] Based on the above test results, Figure 1 and Figure 2 As shown, a flow meter 3 is also provided on the liquid inlet pipeline 13 in this embodiment, and the flow meter 3 controls the volume of the fire water entering each liquid treatment tank 1, so that the solid alkali is dissolved in the fire water to form an alkali solution of a certain concentration. When the flow meter 3 is installed, it can be installed on the liquid inlet pipeline at the same time as the control valve 2. When the volume of the fire water entering the liquid treatment tank 1 reaches the set value, the flow meter 3 closes the control valve 2. According to the above test structure, the ratio of the mass of the solid alkali in each liquid treatment tank 1 to the volume of the fire water entering each liquid treatment tank 1 is as follows: 2g to 10g of solid sodium hydroxide is dissolved by 1L of water.

[0069] In addition, in order to allow the alkaline solution formed in the liquid treatment tank 1 to fully treat the thermal runaway flue gas, the following structural optimization can be performed on the liquid treatment tank 1:

[0070] like Figure 3As shown, after the flue gas inlet 11 is set at the top of the liquid treatment tank 1, in order to make the thermal runaway flue gas fully contact with the alkaline solution in the liquid treatment tank 1, the flue gas inlet 11 is connected with a flue gas inlet pipe 15, and at least part of the flue gas inlet pipe 15 can be immersed in the alkaline solution. Optimally, the flue gas inlet pipe 15 preferably extends to the bottom of the liquid treatment tank 1 and can be completely immersed in the alkaline solution. When the thermal runaway flue gas passes through the liquid treatment tank 1, it fully contacts the alkaline solution in the liquid treatment tank 1, and the alkaline solution fully treats the thermal runaway flue gas, thereby improving the treatment effect of the alkaline solution.

[0071] like Figure 3 As shown, a diversion portion 16 may also be provided at one end of the smoke inlet pipe 15 immersed in the alkaline solution. The diversion portion 16 disperses and diverts the thermal runaway flue gas before reacting with the alkaline solution in the liquid treatment tank 1, so that the thermal runaway flue gas enters in a large flow and exits in a small flow, which is beneficial to the dispersion of the thermal runaway flue gas, so that the thermal runaway flue gas and the alkaline solution are fully contacted and reacted, thereby improving the treatment effect of the alkaline solution. In the present embodiment, the diversion portion 16 is a foam copper column, which is easy to install and has a better dispersion and diversion effect. When the foam copper column is specifically installed, it is fixed to the port at one end of the smoke inlet pipe 15 immersed in the alkaline solution. Foam copper is a structure with a large number of three-dimensional holes in a copper matrix, which has a dispersing and buffering effect on the fluid. When in use, it is processed into a columnar structure, and the thermal runaway flue gas flows out from the foam copper column through the smoke inlet pipe 15, and then flows out through the side wall or bottom of the foam copper column to achieve the dispersion and buffering effect on the thermal runaway flue gas, so that the thermal runaway flue gas after diversion can fully contact with the alkaline solution.

[0072] like Figure 4 and Figure 5 As shown, in order to further allow the thermal runaway flue gas to fully react with the alkaline solution, a spiral baffle 17 is provided on the above-mentioned smoke inlet pipe 15, or a plurality of baffles 18 are provided on the smoke inlet pipe 15. The spiral baffle 17 or a plurality of baffles 18 increase the travel of the thermal runaway flue gas when the thermal runaway flue gas passes through the liquid treatment tank 1, so that the thermal runaway flue gas can more fully contact with the alkaline solution. The thermal runaway flue gas enters from the flue gas inlet 11 of the liquid treatment tank 1, and then enters the bottom of the alkaline solution through the smoke inlet pipe 15, and then is broken up by the foam copper column. Then, during the process of rising from the bottom, the spiral baffle 17 or a plurality of baffles 18 will allow the thermal runaway flue gas to fully contact with the alkaline solution in the liquid treatment tank 1, so as to perform corresponding treatment. When specifically connected, the spiral baffle 17 can be fixed on the smoke inlet pipe 15. The baffles 18 are semicircular baffles, and a plurality of baffles 18 are arranged in sequence from bottom to top and are respectively fixed on the smoke inlet pipe 15 , and adjacent baffles 18 are installed in a staggered manner.

[0073] Example 2

[0074] like Figure 6As shown, the thermal runaway flue gas treatment device in this embodiment is similar to the thermal runaway flue gas treatment device in Example 1. The difference from Example 1 is that in the thermal runaway flue gas treatment device in this embodiment, the liquid inlet pipeline 13 of the liquid treatment tank 1 is used to connect with the temperature control pipeline, and the cooling water in the temperature control pipeline is introduced into the liquid treatment tank 1. The solid alkali in the liquid treatment tank 1 is dissolved by the cooling water to form an alkaline solution.

[0075] In order to ensure the reliable operation of the battery, the existing energy storage equipment is equipped with a temperature control system. The temperature control system generally transports the coolant treated by the chiller and other devices to the battery accessories through the temperature control pipeline to control the temperature of the battery so that the battery works within a better temperature range. The above-mentioned temperature control system generally uses cooling water as the coolant. At this time, the temperature control pipeline of the temperature control system can be connected to the liquid inlet pipeline 13 of the liquid treatment tank 1. When the battery is about to thermally run away, the cooling water in the temperature control pipeline is introduced into the liquid treatment tank 1. The solid alkali in the liquid treatment tank 1 is dissolved by the cooling water to form an alkaline solution.

[0076] When the liquid inlet pipeline 13 in this embodiment is specifically connected to the temperature control pipeline, the liquid inlet pipeline 13 is generally connected to the liquid inlet pipeline in the temperature control pipeline. The advantage of such connection is that the cooling water in the liquid inlet pipeline has a relatively low temperature after being cooled by a chiller or other device. After it is introduced into the liquid treatment tank 1 to form an alkaline solution, the temperature of the alkaline solution is also relatively low. The alkaline solution with a low temperature can cool the thermal runaway flue gas well, so that the temperature of the treated thermal runaway flue gas is relatively low, reducing the possibility of combustion after it is discharged.

[0077] like Figure 6 As shown, the connection between the liquid treatment tank 1 and the liquid inlet pipeline 13 in this embodiment is slightly different. When the liquid inlet pipeline 13 in this embodiment is specifically connected, an opening communicating with the inner cavity of the liquid treatment tank 1 is processed on the side wall of the tank body, and the liquid inlet pipeline 13 is installed on the opening by welding or threaded connection. However, compared with the connection method in Example 1, this connection method requires re-processing and manufacturing the liquid treatment tank 1.

[0078] Similar to Example 1, if there are multiple liquid treatment tanks 1 in the thermal runaway flue gas treatment device, multiple liquid inlet pipelines 13 can also be connected to a manifold 4, and the manifold 4 is connected to the temperature control pipeline.

[0079] Example 3

[0080] This embodiment provides an energy storage device, which mainly includes an energy storage box, a battery cluster, a battery management system (BMS), a temperature control system, and a fire protection system. The battery cluster includes a plurality of battery modules, each of which is closely arranged in the energy storage box. Based on the above structure, the energy storage device in this embodiment also includes the thermal runaway flue gas treatment device in Example 1 or Example 2.

[0081] The liquid inlet pipeline in the above-mentioned thermal runaway flue gas treatment device is connected to the fire-fighting pipeline of the fire-fighting system, and the liquid inlet pipeline introduces the fire-fighting water in the fire-fighting pipeline into the liquid treatment tank, and the solid alkali in the liquid treatment tank is dissolved by the fire-fighting water to form an alkaline solution. Alternatively, the liquid inlet pipeline in the thermal runaway flue gas treatment device is connected to the temperature control pipeline of the temperature control system, and the liquid inlet pipeline introduces the cooling water in the temperature control pipeline into the liquid treatment tank, and the solid alkali in the liquid treatment tank is dissolved by the cooling water to form an alkaline solution.

[0082] In addition, the energy storage device in this embodiment also includes a fire protection system and a thermal runaway smoke treatment device. The thermal runaway smoke treatment device can lead out the thermal runaway smoke of the thermal runaway battery and then process it to avoid the thermal runaway smoke from accumulating in the battery housing. At the same time, after the thermal runaway smoke is led out and processed, it can avoid the occurrence of thermal runaway of other batteries due to heat diffusion when individual batteries are in thermal runaway. When there is thermal runaway smoke in the energy storage box or the battery burns or explodes, the fire protection system prevents the thermal runaway smoke from causing an open flame or extinguishes the battery that has already caught fire. The thermal runaway smoke treatment device and the fire protection system cooperate to provide safety protection for the batteries of the entire energy storage device, thereby improving the safety of the entire energy storage device.

Claims

1. A thermal runaway flue gas treatment device, characterized in that: including at least one liquid handling tank; The liquid treatment tank is provided with a smoke inlet and a smoke outlet communicated with its inner cavity, and the liquid treatment tank is filled with solid alkali; The liquid treatment tank is connected with a liquid inlet pipeline, which is used to introduce external water into the liquid treatment tank. The solid alkali in the liquid treatment tank is dissolved by water to form an alkaline solution, which is used to treat thermal runaway flue gas.

2. The thermal runaway flue gas treatment device according to claim 1, characterized in that: The liquid inlet pipeline is provided with a control valve and a flow meter.

3. The thermal runaway flue gas treatment device according to claim 2, characterized in that: The solid alkali is solid sodium hydroxide, and the ratio of solid sodium hydroxide to water is 2g-10g of solid sodium hydroxide dissolved in 1L of water.

4. The thermal runaway flue gas treatment device according to any one of claims 1 to 3, characterized in that: The smoke inlet and the smoke outlet are both arranged at the top of the liquid treatment tank. The smoke inlet is connected to a smoke inlet pipeline. At least a part of the smoke inlet pipeline can be immersed in the alkaline solution, and a diversion part is arranged at the end of the smoke inlet pipeline immersed in the alkaline solution.

5. The thermal runaway flue gas treatment device according to claim 4, characterized in that: The smoke inlet pipeline is provided with a spiral baffle or a plurality of baffles are provided on the smoke inlet pipeline to increase the travel distance of the thermal runaway flue gas in the liquid treatment tank.

6. The thermal runaway flue gas treatment device according to claim 4, characterized in that: There are multiple liquid treatment tanks, and a three-way valve is provided on the smoke outlet of each liquid treatment tank. The first port of the three-way valve is connected to the inner cavity of the liquid treatment tank, the second port is used to discharge the thermal runaway smoke, and the third port is connected to the liquid inlet pipeline. Each liquid inlet pipeline is connected to the manifold.

7. The thermal runaway flue gas treatment device according to claim 4, characterized in that: There are multiple liquid processing tanks, and the liquid inlet pipeline of each liquid processing tank is arranged on the side wall of the tank body of the liquid processing tank, and each liquid inlet pipeline is connected to the manifold.

8. An energy storage device, characterized in that: It comprises a plurality of battery modules, a temperature control system, a fire protection system and the thermal runaway smoke treatment device according to any one of claims 1 to 7.

9. The energy storage device according to claim 8, characterized in that: The liquid inlet pipeline is connected to the fire-fighting pipeline of the fire-fighting system, and the liquid inlet pipeline introduces the fire-fighting water in the fire-fighting pipeline into the liquid treatment tank. The solid alkali in the liquid treatment tank is dissolved by the fire-fighting water to form an alkali solution.

10. The energy storage device according to claim 8, characterized in that: The liquid inlet pipeline is connected to the temperature control pipeline of the temperature control system, and the liquid inlet pipeline introduces the cooling water in the temperature control pipeline into the liquid treatment tank. The solid alkali in the liquid treatment tank is dissolved by the cooling water to form an alkali solution.

11. The energy storage device according to claim 10, characterized in that: The liquid inlet pipeline is used to be connected to the liquid inlet pipeline in the temperature control pipeline.

Images