Thermal runaway suppression device and method, battery pack, battery and electric vehicle

Abstract

The present invention relates to a thermal runaway suppression device for a battery pack equipped with a coolant circuit for cooling an array of battery cells in the battery pack, the thermal runaway suppression device comprising: a high-pressure pump, the input end of which is fluidly connected to an inlet pipe section of the coolant circuit; at least one ejector in fluid connection with the output end of the high-pressure pump, the ejector being arranged in the battery pack and located on a first end side of the battery cell array; a nozzle of the ejector is positioned towards a second end side, opposite to the first end side, of the battery cell array and towards a gap between the upper end of the battery cell and the upper cover part of the battery pack shell, and the thermal runaway suppression device further comprises a control module in communication connection with a battery pack management system; the control module is configured to control the spray of the injector according to a battery thermal runaway signal from the battery pack management system. The invention further relates to a battery pack, a battery, an electric vehicle, a thermal runaway suppression method, computer equipment and a computer readable storage medium.

Description

Technical Field

[0001] The present invention relates to the field of electrochemical energy storage power station control technology, and more specifically to a thermal runaway suppression device for a battery pack, a battery pack, a battery and an electric vehicle having the thermal runaway suppression device, and a thermal runaway suppression method, a computer device and a computer-readable storage medium performed using the thermal runaway suppression device. Background Art

[0002] At present, batteries have been widely used in various technical fields involving energy storage, especially in the field of new energy electric vehicles. The safety of battery packs is the basis of all battery design and process production, and safety indicators have been running through the entire process of design and process production of each component. The battery cell is the basic energy unit of the battery pack. The battery pack includes battery cells arranged in an array and connected in series and parallel. The battery cell can be implemented in the form of a battery cell, or implemented as a module composed of several battery cells connected in series and parallel. Due to defects in the battery cell itself or in the presence of external mechanical damage, electrical abuse, and thermal abuse inducements, irreversible chemical reactions will occur inside the battery cell, and the energy stored in the electrochemical way will be released in the form of heat, that is, thermal runaway will occur. In the state of thermal runaway, the battery will release a large amount of smoke containing combustible substances. The ignition energy required for these smoke is very small. With the help of oxygen in the air, the smoke is very easy to burn, and even explodes when it is severe.

[0003] With the development of battery cell energy density, the maximum temperature of thermal runaway and the impact strength of high-temperature airflow have increased accordingly, with the maximum temperature reaching 1200°C and the pressure strength of the airflow built up instantly during thermal runaway reaching 1MPa. The battery pack shell cannot withstand such high temperature and pressure. The impact of high-temperature flames can quickly burn through the battery pack shell and ignite the vehicle body, seriously threatening the safety of the passengers.

[0004] In response to the phenomenon of battery thermal runaway, the existing solutions are divided into active and passive. Passive solutions include adding flame retardant materials between battery cells and placing metal plates filled with fire extinguishing agents above the battery cells. Among them, adding flame retardant materials between battery cells has been widely adopted, but it increases the weight of the battery pack and the effect is relatively limited. The active solution is to add one or more sets of electronically controllable fire extinguishers to the battery pack. This solution requires a lot of extra space to carry the fire extinguishing agent tank, which will reduce the energy density of the battery pack or shorten the vehicle's cruising range. Therefore, it is mainly used in commercial vehicles with more space.

[0005] Most of the existing sprinkler fire extinguishing systems for batteries are independent of the battery cooling circuit, including a liquid storage tank placed away from the battery pack on the electric vehicle and a complex pipe network extending from the liquid storage tank. The design and layout of the pipe network are complex and require a large installation space. The pipe network is arranged above the battery cell. This installation method will increase the vertical height of the battery pack, the battery pack space utilization rate is low and the battery pack specific energy density is reduced. In addition, due to the small pressure distributed to each sprinkler pipe, this direct spray cooling method has a low spray speed and limited cooling effect.

[0006] The existing spray-type fire extinguishing system uses high-pressure gas to spray liquid medium, and the gas impacts the liquid medium to form fine water mist. However, this method produces coarse atomized particles, and the droplet coverage is uneven. If the water mist particles are too large or the water mist accumulates into liquid water, the droplet evaporation rate will decrease, resulting in a decrease in the cooling effect. In addition, the high-pressure gas storage system is large and complex, and also occupies a large part of the space. Summary of the invention

[0007] In view of this, the present invention aims to provide a thermal runaway suppression device for a battery pack, a battery pack, a battery and an electric vehicle having the thermal runaway suppression device, which can effectively and quickly suppress thermal runaway with a compact structure and a simple and convenient automatic control method, and ensure the safe use of the battery pack, the battery and the electric vehicle. In addition, the thermal runaway suppression device can be installed in a modular manner, so that it can be flexibly combined and matched with various battery pack sizes and spaces without redesigning the battery pack and its coolant circuit, so as to meet the thermal runaway suppression and fire extinguishing requirements of different battery packs.

[0008] According to one aspect of the present invention, there is provided a thermal runaway suppression device for a battery pack, the battery pack being equipped with a cooling liquid circuit for cooling a battery cell array in the battery pack, the thermal runaway suppression device comprising:

[0009] A high-pressure pump, an input end of the high-pressure pump is fluidically connected to an inlet pipe section of a coolant circuit that leads into the interior of the battery pack;

[0010] at least one injector fluidly connected to an output of the high-pressure pump,

[0011] wherein the at least one injector is disposed in the battery pack and located at a first end side of the battery cell array, and a nozzle of the at least one injector is positioned to spray toward a second end side of the battery cell array opposite to the first end side and toward a gap between an upper end of the battery cell and an upper cover portion of a battery pack shell,

[0012] The thermal runaway suppression device further includes a control module communicatively connected to a battery pack management system for the battery pack, wherein the control module is configured to control the spray of the at least one injector according to a battery thermal runaway signal from the battery pack management system.

[0013] The thermal runaway suppression device according to the present invention can advantageously utilize a high-pressure pump and an injector to atomize the coolant from the coolant circuit and utilize high-pressure spray to cool the high-temperature flue gas and adsorb oxygen, thereby effectively improving the cooling effect. In addition, through the control module, it is possible to respond in real time and quickly to prevent the occurrence of thermal runaway, minimize the possibility of battery explosion, and ensure the safety of the vehicle body and occupants. The addition of the entire thermal runaway suppression device does not increase the vertical height of the battery pack, so the density of the resulting battery pack can be flexibly designed as needed.

[0014] In one embodiment, the control module is in communication with the high pressure pump, or the control module is in communication with the high pressure pump and the at least one injector.

[0015] In one embodiment, the input end of the high-pressure pump is connected to the inlet pipe section of the coolant circuit via a three-way valve.

[0016] In one embodiment, the control module is in communication with the three-way valve.

[0017] In one embodiment, the high-pressure pump is arranged in the battery pack.

[0018] In one embodiment, the at least one injector includes two or more injectors arranged along the first end side of the battery cell array.

[0019] In one embodiment, the at least one injector is disposed near an edge of the battery pack and approximately in the middle of the first end side of the battery cell array.

[0020] In one embodiment, at least one of the at least one injector is configured such that its nozzle can swing within a certain angle range within a plane where the gap is located.

[0021] In one embodiment, the coolant circulating in the coolant loop is water or ethylene glycol solution or a mixture thereof.

[0022] In one embodiment, the battery unit is a battery cell.

[0023] According to another aspect of the present invention, a battery pack is provided, comprising a shell, a battery cell array in the shell, and a coolant circuit configured to cool the battery cells, wherein the battery pack further comprises the above-mentioned thermal runaway suppression device.

[0024] According to yet another aspect of the present invention, a battery is provided, characterized in that the battery comprises the above-mentioned battery pack.

[0025] According to yet another aspect of the present invention, there is provided an electric vehicle, characterized in that the electric vehicle comprises the above-mentioned battery.

[0026] According to another aspect of the present invention, there is provided a thermal runaway suppression method performed by using the thermal runaway suppression device, comprising:

[0027] In response to the battery thermal runaway signal from the battery pack management system, the control module sends operating commands to the high-pressure pump and injectors.

[0028] In one embodiment, the operation instruction includes controlling the injector to open and close in a certain cycle to perform intermittent spraying, each cycle includes the injector's opening spraying time and the injector's closing time, and the ratio of the injector's opening spraying time to the entire cycle time is the duty cycle.

[0029] In one embodiment, the control module adjusts the cycle time and / or duty cycle in real time according to a temperature signal from a battery pack management system.

[0030] In one embodiment, intermittent spraying is performed with a first duty cycle and a first cycle time in a first preset time period starting from the moment the thermal runaway signal is received, and intermittent spraying is performed with a second duty cycle and a second cycle time in a second preset time period starting from the end moment of the first preset time period.

[0031] In one embodiment, the first duty cycle is greater than the second duty cycle.

[0032] In one embodiment, the first cycle time is less than the second cycle time.

[0033] In one embodiment, the first cycle time is 2s, and the first duty cycle is 0.5; the second cycle time is 20s, and the second duty cycle is 0.25.

[0034] In one embodiment, the control module adjusts the output pressure of the high-pressure pump and / or the injection angle of the injector in real time according to a temperature signal from a battery pack management system.

[0035] In one embodiment, the operating instructions include swing instructions for at least one of the at least one injector.

[0036] In one embodiment, the swing instruction includes defining one or more of the following parameters: injector swing angle, swing duration, and swing period.

[0037] According to another aspect of the present invention, a computer device is provided, characterized in that the computer device includes a memory and a processor, the memory and the processor are communicatively connected, the memory stores computer instructions, and the processor executes the thermal runaway suppression method by executing the computer instructions.

[0038] According to yet another aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, the computer program comprising executable instructions, wherein when the executable instructions are executed by a processor, the thermal runaway suppression method is implemented.

[0039] According to the thermal runaway suppression device and method of the present invention, the high-pressure pump pipeline integrated with the coolant circuit, the high-pressure pumping performance of the high-pressure pump and the efficient spraying performance of the injector are utilized to advantageously realize the compact structure of the battery pack without requiring too much fire-fighting device installation space. Advantageously, by arranging a single or several injectors between the upper cover portion of the battery pack shell and the air gap on the upper surface of the battery unit (preferably the battery cell) and pumping fluid by the high-pressure pump, the spray can cover the battery cells of all battery units in a horizontal spraying manner. The thermal runaway suppression device of the present invention is low-cost and suitable for the narrow space of the battery pack. With the help of the sensitive and quick response of the control module and the close-range and fine droplet spray of the injector, the spray cooling instruction can be executed in a timely and effective manner and a significant cooling and oxygen-repelling effect can be achieved, so that the temperature of the thermal runaway battery drops sharply and aerobic combustion is suppressed. In addition, by optimizing the injection strategy and adopting intermittent spraying, not only can the coolant be saved, but also the cooling performance can be extended and the oxygen-repelling performance can be effectively improved.

[0040] In addition, the thermal runaway suppression system of the present invention facilitates the addition of a fire extinguishing function without changing the existing piping arrangement. This modification method for the existing battery cooling and fire protection system greatly saves costs and space requirements. Different types of battery packs have different available spaces and internal arrangements. In order to adapt to different types of battery packs, the positions of the main functional units (injector, high-pressure pump, three-way valve) of the thermal runaway suppression device of the present invention can be freely adjusted through customizable length pipelines. If necessary, the high-pressure pump and three-way valve can be installed outside the battery pack, leaving only the injector inside the battery pack. The three-way valve can select the appropriate interface according to the diameter of the original coolant pipeline of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Features and advantages of one example of the present invention will become apparent with reference to the following detailed description and accompanying drawings, in which:

[0042] Figure 1 A top view of a battery pack according to the present invention with an upper cover portion of the packing case removed is shown;

[0043] Figure 2A vertical cross-sectional schematic diagram of a battery pack according to the present invention is shown;

[0044] Figure 3 The integration of the coolant circuit and the thermal runaway suppression device of the battery pack according to the present invention is shown;

[0045] Figure 4 A schematic diagram showing a pipeline according to an embodiment of a thermal runaway suppression device of the present invention;

[0046] Figure 5 A schematic diagram showing signal connections between a thermal runaway suppression device and a battery pack management system according to an exemplary embodiment of the present invention;

[0047] Figure 6 A schematic diagram showing intermittent spraying of a thermal runaway suppression method according to an exemplary embodiment of the present invention; and

[0048] Figure 7 A schematic diagram of the hardware structure of a computer device according to an exemplary embodiment of the present invention is shown. DETAILED DESCRIPTION

[0049] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0050] In the description of the embodiments of the present invention, it should be understood that the terms "up", "down", "length", "width", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present invention.

[0051] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0052] In the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0053] It should also be noted that in the embodiments of the present invention, the same figure mark is used to represent the same component or the same part. For the same parts in the embodiments of the present invention, the figure may only mark the figure with one of the parts or components as an example. It should be understood that the figure mark is also applicable to other identical parts or components.

[0054] The battery, which is the heart of new energy electric vehicles, includes one or more battery packs. Figure 1 An example of a battery pack 1 according to the present invention is shown. The battery pack may include a plurality of battery units M arranged in an array, and the battery unit may be implemented in the form of a module composed of several battery cells connected in series and in parallel, or a single battery cell. Figure 1 The battery unit M shown in the figure is a battery cell (i.e., the battery pack shown in the figure is a module-free structure), wherein there is a certain gap between the battery cells, and a coolant heat exchange plate or a heat insulation layer is usually arranged in these gaps. Most pure electric new energy vehicle battery packs use liquid cooling to control the battery pack temperature, such as Figure 1 As shown, the coolant circuit C for cooling the battery has an inlet pipe section C_in that leads to the inside of the battery pack shell 10, a coolant flow passage C_c that extends from the inlet pipe section in the gap between the battery cells, and an outlet pipe section C_out that is fluidly connected to these coolant flow passages and leads from the inside of the battery pack to the outside of the battery pack. As a result, while the coolant flows in the coolant flow passage, it also takes away the heat dissipated by the battery cells. The coolant flowing out of the outlet pipe section is temperature-adjusted by an external heat exchanger and flows through a liquid storage tank, and finally circulates back to the inlet pipe section and re-enters the battery pack to cool the battery cells. The coolant circulating in the coolant circuit is water or ethylene glycol solution or a mixture thereof. In order to maintain the normal operating temperature of the battery and the temperature of other components in the vehicle, a new energy vehicle may require 10-20L of such coolant, which is centrally stored in a liquid storage tank.

[0055] Figure 1 Only part of the pipeline in the coolant circuit C inside the battery pack is shown.

[0056] like Figure 1-3As shown, the thermal runaway suppression device 11 according to the present invention includes a high-pressure pump 110 and an injector 111. The high-pressure pump and the injector are the main execution module components of the thermal runaway suppression device of the present invention. The input end of the high-pressure pump is fluidically connected to the inlet pipe section C_in of the coolant circuit that leads into the battery pack. The injector 111 is fluidically connected to the output end of the high-pressure pump 110, so that the high-pressure pump acts as a pressure driving source to drive the coolant into the injector and is atomized by the injector and then ejected from the nozzle. Therefore, the thermal runaway suppression device according to the present invention can be regarded as a section of fire extinguishing pipeline D (such as) added on the basis of the coolant circuit used for normal cooling of the battery pack. Figure 3 The fire extinguishing pipeline uses these coolants to extinguish fire and cool down the battery pack in an emergency, inhibit the spread of thermal runaway between battery cells, eliminate the flames caused by thermal runaway, and avoid the problem of existing solutions requiring additional fire extinguishing agent tanks or other forms of additional storage devices.

[0057] Combination Figure 1 and Figure 2 As shown, the high-pressure pump 110 and the injector 111 are both located inside the battery pack shell 10 and close to the edge of the battery pack shell and on the left end side of the battery cell array. Through the design of the pipeline where the high-pressure pump and the injector are located, the injector 111 can be positioned roughly in the center of the left end side of the battery cell array and at a position higher than the upper end side of the battery cell array. The nozzle of the injector 111 is positioned toward the right end side of the battery cell array and toward the gap between the upper end side of the battery cell array and the upper cover part 101 of the battery pack shell opposite thereto. Therefore, the spray ejected from the nozzle of the injector 111 flows roughly in the horizontal plane where the gap is located. The range of the spray is large enough to cover the dimension of the battery pack in the length direction L. The injection angle of the injector is designed to be large enough to ensure that the spray can also cover the battery cell array in the width direction W. The injector 111 can be positioned to facilitate the sprayed mist to evenly cover the entire battery pack and minimize the injection dead angle.

[0058] As a result, the formed spray flows in the gap between the upper cover portion 101 of the shell and the upper end side of the battery cell array, and the fine atomized particles evaporate quickly on the surface of the high-temperature battery cell / object to take away the heat. As a result, the spray absorbs the combustible smoke particles escaping from the battery pressure relief valve while cooling, avoiding the hidden danger of uncontrolled smoke being discharged to the outside of the battery and catching fire, effectively suppressing thermal runaway and preventing the battery cell from exploding due to excessive temperature.

[0059] Although only one injector is shown in the figure, it is understood that multiple injectors may be provided, the input end of which is fluidically connected to the output end of the high pressure pump. Figure 1The left end of the battery cell array shown is lined up in a row, which effectively utilizes the space near the left end of the battery cell array in the battery pack, and by superimposing the spray in the width direction W of the battery cell array, a more effective spray can be formed to suppress thermal runaway.

[0060] like Figure 1 The thermal runaway suppression device 11 according to the present invention further includes a three-way valve 112. The three-way valve connects the input end of the high-pressure pump 110 and the inlet pipe section C_in of the coolant circuit C. Figure 3 and Figure 4 , the three-way valve 112 makes it possible to add the fire extinguishing pipeline D where the high-pressure pump 110 and the injector 111 are located to the inlet pipe section C_in of the coolant circuit C in a simple and easy manner. That is to say, by using the three-way valve as an adapter, the entire pipeline assembly with the high-pressure pump and the injector in series can be conveniently connected to the coolant circuit without excessive or complicated installation steps. Of course, the three-way valve can also be replaced by a solenoid valve or any other valve body that can be controlled to open and close by an electrical signal, which is respectively arranged in the pipeline where the high-pressure pump is located and in the coolant inlet pipe section.

[0061] like Figure 5 As shown, the thermal runaway suppression device 11 according to the present invention further includes a control module 113 that is communicatively connected to a battery pack management system BMS for a battery pack, and the control module 113 is configured to control the spray of the injector 111 according to a battery thermal runaway signal from the battery pack management system BMS. Figure 4 In the illustrated embodiment, the control module is in communication with the three-way valve 112, the high-pressure pump 110 and the injector 111, and is capable of sending control instructions to the three-way valve and / or the high-pressure pump and / or the injector to control the spray of the injector. The battery pack management system determines whether the battery may enter a runaway state based on the measured values ​​of the temperature, voltage, current, etc. in the battery pack. Once the battery pack management system generates a battery thermal runaway signal and sends this signal to the control module, the control module immediately sends a control instruction to start the spray to the three-way valve, the high-pressure pump and the injector.

[0062] In an embodiment in which the fire extinguishing line D is connected to the coolant circuit C through the three-way valve 112, when the battery pack is operating normally, the three-way valve 112 keeps the coolant circuit unobstructed, and the connection between the fire extinguishing line D and the coolant circuit is disconnected. At this time, the coolant flows through the coolant flow path in the battery pack through the three-way valve 112 to cool the battery pack. In the event of an emergency such as battery thermal runaway, the three-way valve 112 receives a control instruction from the control module, disconnects the coolant circuit C, and connects the fire extinguishing line D. At the same time, the high-pressure pump 110 receives a control instruction from the control module and starts running. At this time, the coolant flows through the high-pressure pump 110, is pressurized, atomized by the injector 111, and evenly sprayed into the battery pack, quickly cooling the battery pack, thereby suppressing thermal runaway and preventing fire.

[0063] It is understood that, in the case where the high-pressure pump can be directly controlled by electronic control, the three-way valve can be omitted in the connecting pipeline between the high-pressure pump and the coolant circuit. The control module can be directly connected to the high-pressure pump to control the opening and closing of the spray. Alternatively, in the case where it is necessary to fine-tune the spray, the control module is connected to the high-pressure pump 110 and the injector 111 to obtain the best spray effect.

[0064] In an advantageous embodiment, the ejector 111 is designed such that its outlet can swing within a certain angle range in the plane where the gap is located. When multiple ejectors are provided, one or more of the multiple ejectors are designed to swing within a certain angle range in the plane where the gap is located. The swing angles of these ejectors can be designed to be the same or different according to the spray coverage requirements.

[0065] exist Figure 1 and 2 In the embodiment shown in , the high-pressure pump 110 is arranged in the battery pack shell 10. However, it can be understood that, if the available space is limited, the high-pressure pump can also be arranged outside the battery pack shell. The three-way valve 112 can also be arranged in the section of the coolant inlet pipe section located outside the battery pack shell.

[0066] The injector used in the thermal runaway suppression device of the present invention can be directly obtained from the market, and can be easily selected according to the atomization requirements and the like.

[0067] The battery according to the present invention comprises the battery pack described above. The electric vehicle according to the present invention comprises the battery described above.

[0068] Refer to the following Figure 6 A thermal runaway suppression method performed using the thermal runaway suppression device of the present invention will be described.

[0069] The control module 113 in the thermal runaway suppression device of the present invention can communicate with the battery pack management system BMS, receive instructions or signals sent by the battery pack management system BMS, and if a battery thermal runaway signal is received, the three-way valve 112 is controlled to disconnect the coolant circuit C and connect the fire extinguishing pipeline D. Therefore, in the thermal runaway suppression method of the present invention, in response to the battery thermal runaway signal from the battery pack management system, the control module sends an operation instruction to the three-way valve 112, the high-pressure pump 110 and the injector 111.

[0070] In a specific embodiment, the operation instruction includes controlling the injector 111 to open and close in a certain cycle to perform intermittent spraying, each cycle includes the injector's opening spraying time t_s and the injector's closing time t_cl, and the ratio of the injector's opening spraying time t_s to the entire cycle time t_c is the duty cycle. Compared with continuous spraying, intermittent spraying has a better cooling effect, and can also save coolant, which is beneficial to reduce the battery temperature to a lower level. When the duty cycle is the same, the spray cycle time is different, and the cooling effect obtained is also different. Generally speaking, the shorter the spray cycle time, the better the cooling effect. When the spray cycle time is the same, the duty cycle is different, and the cooling effect obtained is also different. Generally speaking, the larger the duty cycle, the better the cooling effect.

[0071] Therefore, the control module 113 can also be configured to adjust the spray cycle time and / or duty cycle in real time according to the battery temperature signal from the battery pack management system. Thus, the sprayer is controlled to open and close according to a certain cycle, and spray at a certain duty cycle, so that the spray coverage is uniform, the cooling effect of atomization evaporation is maximized, and the cooling performance and flame suppression effect are optimized.

[0072] In a specific embodiment, intermittent spraying is performed with a first duty cycle and a first cycle time in a first preset time period from the moment when the thermal runaway signal is received, and intermittent spraying is performed with a second duty cycle and a second cycle time in a second preset time period from the end moment of the first preset time period. Advantageously, the first duty cycle is greater than the second duty cycle. The first cycle time is less than the second cycle time. In an example embodiment, the first preset time period is 100s, the first cycle time is 2s, and the first duty cycle is 0.5; the second preset time period is 200s, the second cycle time is 20s, and the second duty cycle is 0.25. Thus, thermal runaway suppression is divided into two stages, the first stage suppresses and extinguishes the flame (thermal runaway development stage), and the second stage cools down and prevents the thermal runaway from spreading to other cells (cooling stage). In the first stage (first preset time period), a shorter spray cycle and a larger duty cycle are used. The spray cycle can better ensure the cooling effect. At the same time, the pulsed water mist can quickly dilute the oxygen concentration in the battery pack and disperse and contain the flame. In the second stage (second preset time period), a longer spray cycle and a smaller duty cycle are selected to enable the water mist to form a thinner water film between the battery cells to prevent thermal runaway from spreading to adjacent battery cells. At the same time, the water film will not be too thick to affect the evaporation rate and reduce the cooling effect.

[0073] In a favorable embodiment, the control module 113 can also be configured to adjust the output pressure of the high-pressure pump in real time according to the battery temperature signal from the battery pack management system. When the high-pressure pump and the injector work together, the injection flow rate is proportional to the injection pressure. The greater the pressure, the smaller the spray particle size. Since a larger injection speed can help the water mist particles penetrate the strong airflow and flame jet during the thermal runaway eruption of the battery cell to reach the surface of the battery cell, and at the same time, a larger flow rate and smaller particles mean a faster cooling rate, the greater the pressure, the better the cooling effect. However, the cooling effect gain brought about by this pressure increase also has a marginal diminishing effect. In actual use, it is impossible to increase the pressure indefinitely, but it is necessary to consider the pressure resistance level of the battery cell and the pipeline network actually used in the battery pack. The control module can select an appropriate injection pressure from the range of 5-30bar according to the cooling requirements.

[0074] In an advantageous embodiment, the control module 113 can also be configured to adjust the injection angle of the injector 111 in real time according to the battery temperature signal from the battery pack management system. For the same high-pressure pump output pressure, the larger the injector injection angle, the smaller the range. In combination with the detection of the battery pack length and the monitoring of the battery temperature, the control module can select to adjust the injector at a suitable injection angle.

[0075] In a preferred embodiment of the thermal runaway suppression method of the present invention, the operating instructions from the control module 113 include a swing instruction for at least one injector. The swing instruction includes defining one or more of the following parameters: injector swing angle, swing duration, and swing period. When it is detected that the temperature of some battery cells is abnormally high, an injector whose spray scanning range can cover a large area of ​​the battery cell can be selected for swing spraying, thereby avoiding the arrangement of too many injectors, simplifying the installation process and making the battery pack structure more compact. The swing angle, swing duration or swing period can also change according to the change of temperature detection data.

[0076] In the thermal runaway suppression device and method of the present invention, the nozzle of the injector can be a special nozzle designed according to the selected boundary parameters such as pressure, range, angle and atomized particle diameter to achieve the desired injection function. Preferably, the nozzle can be added with a solenoid valve or any electronic drive component on the basis of the above design so that it can be periodically opened and closed under the drive of the control module to complete the intermittent spraying function.

[0077] The specific definition and beneficial effects of the above-mentioned thermal runaway suppression method can be found in the above-mentioned definition of the thermal runaway suppression device, which will not be repeated here. The above-mentioned modules can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0078] Figure 7 FIG. 1 is a schematic diagram of a hardware structure of a computer device according to an exemplary embodiment. Figure 7 As shown, the device includes one or more processors 210 and a memory 220, and the memory may be a persistent memory, a volatile memory or a hard disk. Figure 7 A processor is used as an example. The device may also include: an input device 230 and an output device 240. The processor, memory, input device and output device may be connected via a bus or other means. Figure 7 The example of connecting through bus is taken in the following.

[0079] The processor 210 may be a central processing unit. The processor 210 may also be other general-purpose processors, digital signal processors, application-specific integrated circuits, field programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips. The general-purpose processor may be a microprocessor. The processor 210 may also be any conventional processor, etc.

[0080] The memory 220 is a non-transitory computer-readable storage medium, which may be a persistent memory, a volatile memory or a hard disk, and may be used to store non-transitory software programs, non-transitory computer executable programs and modules. The processor 210 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions and modules stored in the memory 220, that is, to implement the above-mentioned thermal runaway suppression method.

[0081] The memory 220 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required by at least one function; the data storage area may store data used as needed, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the data processing device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0082] The input device 230 can receive input digital or character information and generate key signal input related to user settings and function control. The output device 240 can include display devices such as a display screen.

[0083] When the computer instructions stored in the memory 220 are executed by the processor 210, the execution Figure 6 The method shown.

[0084] The embodiment of the present invention further provides a computer-readable storage medium, on which computer-executable instructions are stored, and when the computer-executable instructions are executed by a processor of a computer, the processor can execute the above-mentioned thermal runaway suppression method. The storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state drive, etc.; the storage medium can also include any combination of the above-mentioned types of memory.

[0085] The above merely describes an exemplary embodiment of the method and apparatus for suppressing thermal runaway according to the present invention. The method and apparatus are not limited to the specific embodiments described herein. "An example", "another example", "example", etc. mentioned throughout the specification mean that a certain element / element (such as a feature, structure and / or characteristic) related to the example is included in at least one example described herein, and may appear and / or may not appear in other examples. In addition, it is understood that multiple elements of any example described may be combined in any suitable manner in multiple different examples, unless the context clearly indicates otherwise.

[0086] This specification uses examples to disclose the present invention, including the best embodiment, and enables any person skilled in the art to implement the present invention. The patentable scope of the present invention is defined by the claims, and may include other examples that may occur to those skilled in the art. If these other examples have structural elements that are not distinguished from the literal language of the claims, or if these other examples include structural elements that are not substantially distinguished from the literal language of the claims, then these other examples should fall within the scope of the claims.

Claims

1. A thermal runaway suppression device for a battery pack, the battery pack being equipped with a cooling liquid circuit for cooling a battery cell array in the battery pack, the thermal runaway suppression device comprising: A high-pressure pump, an input end of the high-pressure pump is fluidically connected to an inlet pipe section of a coolant circuit that leads into the interior of the battery pack; at least one injector fluidly connected to an output of the high-pressure pump, Wherein the at least one injector is arranged in the battery pack and is located on the first end side of the battery cell array, and the nozzle of the at least one injector is positioned to spray toward the second end side of the battery cell array opposite to the first end side and toward the gap between the upper end of the battery cell and the upper cover part of the battery pack shell, and the thermal runaway suppression device also includes a control module communicatively connected to a battery pack management system for the battery pack, and the control module is configured to control the spraying of the at least one injector according to a battery thermal runaway signal from the battery pack management system.

2. The thermal runaway suppression device according to claim 1, characterized in that: The control module is in communication connection with the high pressure pump, or the control module is in communication connection with the high pressure pump and the at least one injector.

3. The thermal runaway suppression device according to claim 1 or 2, characterized in that: The input end of the high-pressure pump is connected to the inlet pipe section of the coolant circuit through a three-way valve.

4. The thermal runaway suppression device according to claim 3, characterized in that: The control module is in communication connection with the three-way valve.

5. The thermal runaway suppression device according to any one of claims 1 to 4, characterized in that: The high-pressure pump is arranged in the battery pack.

6. The thermal runaway suppression device according to any one of claims 1 to 5, characterized in that: The at least one injector includes two or more injectors arranged along a first end side of the battery cell array.

7. The thermal runaway suppression device according to any one of claims 1 to 6, characterized in that: The at least one injector is disposed near an edge of the battery pack and approximately in the middle of a first end side of the battery cell array.

8. The thermal runaway suppression device according to any one of claims 1 to 7, characterized in that: At least one of the at least one injector is configured such that its nozzle can be pivoted within a certain angular range within the plane where the gap is located.

9. The thermal runaway suppression device according to any one of claims 1 to 8, characterized in that: The coolant circulating in the coolant loop is water or ethylene glycol solution.

10. The thermal runaway suppression device according to any one of claims 1 to 9, characterized in that: The battery unit is a battery core.

11. A battery pack comprising a housing, a battery cell array in the housing, and a cooling liquid circuit configured to cool the battery cells, wherein: The battery pack further comprises a thermal runaway suppression device according to any one of claims 1-10.

12. A battery, characterized in that: The battery comprises the battery pack according to claim 11.

13. An electric vehicle, characterized in that: The electric vehicle comprises the battery according to claim 12.

14. A method for suppressing thermal runaway using the thermal runaway suppression device according to any one of claims 1 to 10, comprising: In response to the battery thermal runaway signal from the battery pack management system, the control module sends operating commands to the high-pressure pump and injectors.

15. The method for suppressing thermal runaway according to claim 14, characterized in that: The operation instruction includes controlling the injector to open and close in a certain cycle to perform intermittent spraying, each cycle includes the open spraying time of the injector and the closed time of the injector, and the ratio of the open spraying time of the injector to the entire cycle time is the duty cycle.

16. The method for suppressing thermal runaway according to claim 15, characterized in that: The control module adjusts the cycle time and / or duty cycle in real time according to a temperature signal from a battery pack management system.

17. The method for suppressing thermal runaway according to claim 16, characterized in that: Intermittent spraying is performed with a first duty ratio and a first cycle time in a first preset time period starting from the moment when the thermal runaway signal is received, and intermittent spraying is performed with a second duty ratio and a second cycle time in a second preset time period starting from the end moment of the first preset time period.

18. The method for suppressing thermal runaway according to claim 17, characterized in that: The first duty cycle is greater than the second duty cycle.

19. The method for suppressing thermal runaway according to claim 17 or 18, characterized in that: The first cycle time is shorter than the second cycle time.

20. The method for suppressing thermal runaway according to claim 19, characterized in that: The first cycle time is 2s, and the first duty cycle is 0.5; the second cycle time is 20s, and the second duty cycle is 0.

25.

21. The method for suppressing thermal runaway according to any one of claims 14 to 20, characterized in that: The control module adjusts the output pressure of the high-pressure pump and / or the injection angle of the injector in real time according to the temperature signal from the battery pack management system.

22. The method for suppressing thermal runaway according to any one of claims 14 to 21, characterized in that: The operating command includes a swing command for at least one of the at least one injector.

23. The method for suppressing thermal runaway according to claim 22, characterized in that: The swing command includes defining one or more of the following parameters: injector swing angle, swing duration, and swing period.

24. A computer device, characterized in that: The computer device includes a memory and a processor, the memory and the processor are communicatively connected, the memory stores computer instructions, and the processor executes the thermal runaway suppression method according to any one of claims 14-23 by executing the computer instructions.

25. A computer-readable storage medium having a computer program stored thereon, the computer program comprising executable instructions, characterized in that: When the executable instructions are executed by a processor, the thermal runaway suppression method according to any one of claims 14 to 23 is implemented.

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