Thermal runaway management method, thermal runaway management system and battery pack

Abstract

The invention discloses a thermal runaway management method, a thermal runaway management system and a battery pack. The thermal runaway management method comprises the following steps: acquiring first temperature information acquired by a battery cell monitoring module at a battery cell in a battery pack, second temperature information acquired by a temperature monitoring circuit at the battery cell, and first acquisition information of a fire-fighting assembly in the battery pack; and when at least one of the first temperature information, the second temperature information and the first acquisition information is abnormal, determining a geothermal runaway area in the battery pack, controlling the fire-fighting assembly to execute fire extinguishing in the battery pack, and controlling the gas collection assembly to collect gas in the battery pack, so that the monitoring of the thermal runaway of the battery cell is realized, and the safety of the battery cell is improved. And moreover, thermal runaway diffusion in the battery pack can be controlled in time, and waste gas generated by thermal runaway can be treated in time after the battery cells trigger thermal runaway, so that the safety and reliability of the battery pack are effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a thermal runaway management method, a thermal runaway management system and a battery pack. Background Art

[0002] Thermal runaway refers to the phenomenon that under certain conditions (such as high temperature, overcharging, internal short circuit, etc.), the chemical reaction inside the battery gets out of control, generating a large amount of heat and possibly causing a fire or explosion. Specifically, a short circuit occurs inside the battery, causing the electrolyte to burn or explode, or the positive electrode material decomposes at high temperature to produce oxygen, further exacerbating heat accumulation, or the negative electrode material reacts violently with the electrolyte, causing the temperature to rise rapidly. In addition, excessive discharge of the battery will cause the internal pressure to decrease, all of which will cause thermal runaway. Therefore, how to effectively manage the thermal runaway of the battery is a technical problem that needs to be solved urgently. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present application provides a thermal runaway management method, a thermal runaway management system and a battery pack, which can realize the detection, control and processing of thermal runaway of the battery pack, and can effectively improve the safety and reliability of the battery pack.

[0004] To solve the above problems, in a first aspect, the present application provides a thermal runaway management method, which is applied to a battery pack, the battery pack includes a thermal runaway management system, the thermal runaway management system includes a battery cell monitoring module, a temperature monitoring circuit, a fire protection component and a gas collection component; the method includes:

[0005] Acquire first temperature information collected by the cell monitoring module at the cell in the battery pack, second temperature information collected by the temperature monitoring circuit at the cell, and first collected information of the fire protection component in the battery pack;

[0006] If at least one of the first temperature information, the second temperature information, and the first collected information is abnormal, determining a thermal runaway area in the battery pack;

[0007] The fire fighting component is controlled to perform fire extinguishing in the thermal runaway area, and the gas collecting component is controlled to collect the gas inside the battery pack.

[0008] Further, in the thermal runaway management method provided in the present application, the temperature monitoring circuit includes a thermal switch;

[0009] Before determining the thermal runaway area in the battery pack, it also includes:

[0010] If the first temperature information indicates that the temperature of the battery cell is higher than a preset temperature, determining whether the second temperature information is disconnection information of the thermal switch;

[0011] If the second temperature information is disconnection information, it is determined that the battery cell at the thermal switch is thermally runaway.

[0012] Further, in the thermal runaway management method provided in the present application, the temperature monitoring circuit includes a thermal switch;

[0013] Before determining the thermal runaway area in the battery pack, it also includes:

[0014] If the first temperature information indicates that the temperature of the battery cell is higher than a preset temperature, determining whether the first collected information is the preset first information;

[0015] If the first collected information is the preset first information, it is determined that the battery cell is in thermal runaway.

[0016] Further, in the thermal runaway management method provided in the present application, the temperature monitoring circuit includes a thermal switch;

[0017] Before determining the thermal runaway area in the battery pack, it also includes:

[0018] If the second temperature information is disconnection information of the thermal switch, determining whether the first collected information is the preset first information;

[0019] If the first collected information is the preset first information, it is determined that the battery cell is in thermal runaway.

[0020] Furthermore, in the thermal runaway management method provided in the present application, determining the thermal runaway area in the battery pack includes:

[0021] Get the location information of the battery cell;

[0022] The thermal runaway area within the battery pack is determined based on the location information.

[0023] Further, in the thermal runaway management method provided in the present application, the temperature monitoring circuit includes a plurality of thermal switches, each battery cell corresponds to a thermal switch, the battery pack is provided with a vent valve, and the gas collection assembly includes an airflow assembly and a gas collection pipeline;

[0024] Among them, controlling the gas collection component to collect the gas inside the battery pack includes:

[0025] Activate the gas flow assembly to reduce the pressure inside the gas collection pipe;

[0026] After a preset first time, obtaining on / off information of a thermal switch at a battery cell in the battery pack that has not experienced thermal runaway;

[0027] If the on-off information is the disconnection information of the thermal switch, the ventilation valve is opened to discharge the gas in the battery pack through the ventilation valve and the gas collection pipe in sequence.

[0028] Furthermore, in the thermal runaway management method provided in the present application, the battery pack is also provided with a balancing valve;

[0029] After the vent valve is opened to discharge the gas in the battery pack through the vent valve and the gas collection pipe in sequence, the method further includes:

[0030] After a preset second time, obtaining second collected information of the fire protection component in the battery pack;

[0031] If the second collected information is the preset second information, the balancing valve is opened and the airflow component is controlled to stop working.

[0032] In a second aspect, the present application also provides a thermal runaway management system, which includes:

[0033] A cell monitoring module is disposed inside the battery pack and electrically connected to the cells in the battery pack;

[0034] A temperature monitoring circuit is disposed inside the battery pack and electrically connected to the battery cell monitoring module, and the temperature monitoring circuit is configured to monitor the temperature of the battery cell;

[0035] A fire protection component is disposed inside the battery pack and electrically connected to the battery monitoring circuit;

[0036] A gas collection assembly electrically connected to the battery monitoring circuit and in communication with the interior of the battery pack;

[0037] Among them, the battery cell monitoring module is at least configured to monitor the temperature of the battery cell, and control the fire fighting component to perform fire extinguishing inside the battery pack, and at the same time control the gas collection component to collect gas inside the battery pack.

[0038] Furthermore, in the thermal runaway management system provided in the present application, the temperature monitoring circuit includes a thermal switch; one end of the thermal switch is electrically connected to the battery cell, and the other end of the thermal switch is electrically connected to the temperature monitoring circuit.

[0039] In a third aspect, the present application also provides a battery pack, which includes the thermal runaway management system provided in the second aspect.

[0040] The thermal runaway management method provided in the present application obtains the first temperature information collected by the battery cell monitoring module at the battery cell in the battery pack, the second temperature information collected by the temperature monitoring circuit at the battery cell and the first collected information of the fire protection component in the battery pack. When at least one of the first temperature information, the second temperature information and the first collected information is abnormal, the thermal runaway area in the battery pack is determined, and the fire protection component is controlled to extinguish the fire inside the battery pack and the gas collection component is controlled to collect the gas inside the battery pack. This method not only monitors the thermal runaway of the battery cell, but also timely controls the spread of the thermal runaway in the battery pack. After the battery cell triggers thermal runaway, the exhaust gas generated by the thermal runaway can be processed in time, thereby effectively improving the safety and reliability of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 A first schematic block diagram of a thermal runaway management system provided in an embodiment of the present application;

[0043] Figure 2 A second schematic block diagram of a thermal runaway management system provided in an embodiment of the present application;

[0044] Figure 3 A third schematic block diagram of a thermal runaway management system provided in an embodiment of the present application;

[0045] Figure 4 A fourth schematic block diagram of a thermal runaway management system provided in an embodiment of the present application;

[0046] Figure 5 A circuit diagram of an airflow component provided in an embodiment of the present application;

[0047] Figure 6 A schematic flow chart of a thermal runaway management method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0050] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0051] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0052] In addition, in this application, unless otherwise clearly specified or limited in the embodiments, the terms "installed", "connected", "connected" and "fixed" etc. appearing in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integrated connection. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or 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 this application can be understood according to the specific implementation situation.

[0053] Embodiments of the present application provide a thermal runaway management method, a thermal runaway management system, and a battery pack.

[0054] To facilitate understanding, the thermal runaway management system is first introduced, and then the thermal runaway management method is introduced in detail based on the thermal runaway management system.

[0055] See also Figure 1 , Figure 1 This is a first schematic block diagram of a thermal runaway management system provided in an embodiment of the present application. Figure 1 As shown, a thermal runaway management system 10 includes:

[0056] The battery monitoring circuit 100 is disposed inside the battery pack and electrically connected to the battery cells 20 in the battery pack;

[0057] The fire protection component 200 is disposed inside the battery pack and electrically connected to the battery monitoring circuit 100;

[0058] The gas collection assembly 300 is electrically connected to the battery monitoring circuit 100 and communicates with the interior of the battery pack;

[0059] The battery monitoring circuit 100 is at least configured to monitor the temperature of the battery cell 20, and control the fire fighting component 200 to extinguish the fire inside the battery pack, and control the gas collecting component 300 to collect the gas inside the battery pack.

[0060] In this embodiment, the battery monitoring circuit 100 can monitor the temperature, voltage and current of the battery cell 20 in the battery pack to ensure that the battery operates within a safe range. The fire protection component 200 can directly extinguish the fire inside the battery pack when the battery cell 20 is in thermal runaway, thereby being able to quickly extinguish the battery cell 20 in the thermal runaway state and effectively prevent the battery pack from re-igniting, thereby reducing the risk of secondary damage caused by the battery pack. The gas collection component 300 can collect the exhaust gas generated by the battery cell 20 and discharge it in a directional manner, thereby preventing the exhaust gas from being directly discharged into the air, thereby reducing harm to the environment and human body.

[0061] The thermal runaway management system 10 provided in the present application includes a battery monitoring circuit 100, a fire protection component 200 and a gas collection component 300. The battery monitoring circuit 100 and the fire protection component 200 are both arranged inside the battery pack. The battery monitoring circuit 100 is electrically connected to the battery cell 20 in the battery pack. The fire protection component 200 is electrically connected to the battery monitoring circuit 100. The battery monitoring circuit 100 can be configured to monitor the temperature of the battery cell 20, and after detecting thermal runaway of the battery cell 20, the fire protection component 200 can be controlled to extinguish the fire inside the battery pack and the gas collection component can be controlled to collect the gas inside the battery pack. This not only realizes the monitoring of the thermal runaway of the battery cell 20, but also can timely control the spread of thermal runaway in the battery pack and timely treat the exhaust gas generated by the thermal runaway, effectively improving the safety and reliability of the battery pack.

[0062] In some embodiments, Figure 2 As shown, the battery monitoring circuit 100 includes:

[0063] A battery cell monitoring module 101, electrically connected to the battery cell 20;

[0064] The temperature monitoring circuit 102 is electrically connected to the battery cell monitoring module 101 and is configured to monitor the temperature of the battery cell 20;

[0065] The battery cell monitoring module 101 is configured to monitor the state of the battery, and control the fire fighting component 200 to perform fire extinguishing inside the battery pack, and control the gas collecting component 300 to collect gas inside the battery pack.

[0066] Specifically, the cell monitoring module 101 can monitor the temperature, voltage and current of the cell 20 in the battery pack to ensure that the battery operates within a safe range, and the temperature monitoring circuit 102 can monitor the temperature of each cell 20 in the battery pack. In addition, the cell monitoring module 101 can obtain the temperature of the cell 20 monitored by the temperature monitoring circuit 102 from the temperature monitoring circuit 102, and can further determine whether the cell 20 has thermal runaway, thereby avoiding misjudgment of thermal runaway of the cell 20 and improving the accuracy of thermal runaway monitoring of the cell 20.

[0067] In this embodiment, by simultaneously providing the battery cell monitoring module 101 and the temperature monitoring module in the battery pack, it is possible to avoid misjudgment of thermal runaway of the battery cell 20 and improve the accuracy of thermal runaway monitoring of the battery cell 20. At the same time, the battery cell monitoring module 101 can be a slave control module of the battery management system. As an important part of the battery management system, the slave control module undertakes multiple key tasks such as data collection, balancing management, communication and thermal management, and is a key link to ensure efficient and safe operation of the battery.

[0068] In some embodiments, the temperature monitoring circuit 102 includes a thermal switch; wherein one end of the thermal switch is electrically connected to one end of the battery cell 20 , and the other end of the thermal switch is electrically connected to the battery cell monitoring module 101 .

[0069] Specifically, a thermal switch is an electromechanical temperature control device that uses the different thermal expansion coefficients of the various component layers of the bimetallic strip. When the temperature changes, the deformation of the active layer is greater than that of the passive layer, so that the bimetallic strip as a whole will bend toward the passive layer. The curvature of this composite material changes, thereby producing deformation characteristics to achieve current switching. Thermal switches can change the open / closed state according to changes in ambient temperature. They are divided into positive temperature coefficient and negative temperature coefficient. They are mainly used in safety and control systems to monitor temperature and control related devices. Thermal switches can be implemented using a variety of technologies, including bimetallic switches, thermal reed switches, mercury switches, rod and tube switches with different temperature coefficients, and pneumatic switches.

[0070] When the temperature monitoring circuit 102 is used in the present application to monitor the temperature of the battery cell 20 in the battery pack, a thermal switch can be used to implement the monitoring. The thermal switch has a low cost and does not have the risk of abnormal communication, thereby reducing the misjudgment of thermal runaway of the battery cell 20 and improving the accuracy of thermal runaway monitoring of the battery cell 20. Each battery cell 20 in the battery pack is equipped with a thermal switch. When the battery cell 20 operates normally, the thermal switch is in a closed state; when the battery cell 20 is in thermal runaway, the temperature rises, and the thermal switch is disconnected. At this time, the battery cell monitoring module 101 cannot receive the current signal or voltage information at the thermal switch, and thus it can be determined that the battery cell 20 is in thermal runaway.

[0071] In some embodiments, Figure 3 As shown, the fire protection component 200 includes a smoke detector 201 and a fire extinguishing module 202; wherein, the smoke detector 201 and the fire extinguishing module 202 are both electrically connected to the battery monitoring circuit 100, the smoke detector 201 is configured to detect smoke inside the battery pack, and the fire extinguishing module 202 is configured to perform fire extinguishing inside the battery pack.

[0072] Specifically, the smoke detector 201 is a device specifically used to monitor the internal environment of the battery pack to prevent dangerous situations such as fire and overheating. The smoke detector 201 of the battery pack usually uses a photoelectric or ion sensor to detect smoke and exhaust particles.

[0073] In this embodiment, a smoke detector 201 may be provided corresponding to each battery cell 20 in the battery pack. When a battery cell 20 in the battery pack is in thermal runaway, the corresponding smoke detector 201 may detect the smoke generated by the thermal runaway of the battery cell 20 to determine whether the battery cell 20 has experienced thermal runaway, thereby further reducing the misjudgment of thermal runaway of the battery cell 20 and improving the accuracy of thermal runaway monitoring of the battery cell 20. At the same time, after determining that the battery cell 20 is in thermal runaway, the fire extinguishing module 202 may be used to extinguish the fire to prevent the thermal runaway of the battery cell 20 from spreading and to prevent other battery cells 20 in the battery pack that have not experienced thermal runaway from being affected, thereby effectively improving the safety and reliability of the battery pack.

[0074] Furthermore, in some embodiments, Figure 3 As shown, the fire protection component 200 also includes a fire protection control module 203; wherein the fire protection control module 203 is electrically connected to the battery monitoring circuit 100, the smoke detector 201 and the fire extinguishing module 202 respectively, and the fire protection control module 203 is configured to control the fire extinguishing module 202 to perform fire extinguishing inside the battery pack.

[0075] Specifically, the battery monitoring circuit 100 can obtain the smoke information detected by the smoke detector 201 at the corresponding battery cell 20 through the fire control module 203, and then determine whether the battery cell 20 has thermal runaway. At the same time, after determining that the battery cell 20 is in thermal runaway, the battery monitoring circuit 100 can control the fire extinguishing module 202 to extinguish the fire through the fire control module 203 to prevent the thermal runaway of the battery cell 20 from spreading and avoid other battery cells 20 in the battery pack that have not experienced thermal runaway from being affected, thereby effectively improving the safety and reliability of the battery pack.

[0076] In some embodiments, Figure 4 As shown, the gas collection assembly 300 includes a gas collection pipe 301, and the battery pack is provided with a breathable valve 30; wherein, the gas collection pipe 301 is arranged outside the battery pack; one end of the gas collection pipe 301 is connected to one end of the breathable valve 30, and the other end of the breathable valve 30 is connected to the interior of the battery pack.

[0077] In this embodiment, the gas collection pipe 301 is arranged outside the battery pack. Multiple gas collection inlets can be set at one end of the gas collection pipe 301 and each inlet is connected to a breathable valve 30. The breathable valve 30 can be opened in the process of the gas collection pipe 301 collecting the gas generated by the thermal runaway of the battery cell 20, so that the gas generated by the thermal runaway of the battery cell 20 can be discharged from the battery pack in time and discharged in a direction to prevent the exhaust gas from being directly discharged into the air, thereby reducing the harm to the environment and human body.

[0078] Among them, the air valve 30 is a device used to balance the internal and external pressures of the sealing device to prevent the entry of moisture, dust and other pollutants. Its main function is to maintain good air permeability while preventing the intrusion of water droplets, drizzle, fine impurities and chemicals.

[0079] In some embodiments, the battery pack is further provided with a balancing valve, one end of the balancing valve is connected to the interior of the battery pack, and the other end of the balancing valve is connected to the exterior of the battery pack.

[0080] In this embodiment, the balancing valve is arranged on the box where the battery pack is located and is connected to the inside of the battery pack. The balancing valve can be opened after the thermal runaway of the battery cell 20 in the battery pack is controlled and the exhaust gas in the battery pack is discharged, thereby adjusting the air pressure inside the battery pack to prevent the battery pack from being deformed and suffering secondary damage. The balancing valve can be divided into three types: static balancing valve, dynamic balancing valve and pressure difference independent balancing valve.

[0081] In addition, the balancing valve can also be opened when the battery cell 20 in the battery pack is in thermal runaway and the exhaust gas in the battery pack is discharged to avoid secondary damage to the battery pack due to deformation, which greatly improves the safety and reliability of the battery pack. It should be noted that the opening of the balancing valve can be selected according to the actual application, and this application does not make specific restrictions.

[0082] In some embodiments, Figure 4 As shown, the gas collection component 300 also includes an airflow component 302 and a backup power supply 303; wherein the airflow component 302 is electrically connected to the battery monitoring circuit 100 and the backup power supply 303, and the airflow component 302 is configured to discharge the gas inside the battery pack in sequence through the air valve 30 and the gas collection pipe 301.

[0083] In this embodiment, the airflow component 302 can control the fan, and the power required for the operation of the airflow component 302 can be provided by the battery pack. At the same time, the airflow component 302 can be turned on after the battery cell 20 in the battery pack has thermal runaway to reduce the internal air pressure of the gas collection pipeline 301, so that the exhaust gas generated by the thermal runaway can be sequentially discharged from the air valve 30 to the gas collection pipeline 301 in a direction, thereby preventing the exhaust gas from being directly discharged into the air, thereby reducing the harm to the environment and human body.

[0084] At the same time, the airflow collection component can also be equipped with a backup power supply 303, so that when the battery pack cannot provide power to the airflow component 302, the backup power supply 303 can provide power to the airflow component 302 to ensure that the airflow component 302 can continue to operate, so as to reduce the internal air pressure of the gas collection pipeline 301, so that the exhaust gas generated by thermal runaway can be directionally discharged in turn through the air valve 30 and the gas collection pipeline 301, thereby preventing the exhaust gas from being directly discharged into the air, thereby reducing the harm to the environment and human body.

[0085] Furthermore, in some embodiments, the gas collection assembly 300 also includes a control circuit, which is electrically connected to the battery cell monitoring module 101, the airflow assembly 302 and the backup power supply 303 respectively.

[0086] In this embodiment, the battery cell monitoring module 101 turns on the airflow component 302 through the control circuit. At the same time, when the battery pack cannot provide power for the airflow component 302, the backup power supply 303 can power the airflow component 302 through the control circuit to ensure that the airflow component 302 can be turned on after the battery cell 20 in the battery pack has thermal runaway, so as to reduce the internal air pressure of the gas collection pipe 301, so that the exhaust gas generated by the thermal runaway can be directionally discharged in sequence through the air valve 30 and the gas collection pipe 301.

[0087] Furthermore, in some embodiments, Figure 5 As shown, the control circuit includes a first switch 304, a second switch 305, a third switch 306 and a fourth switch 307, one end of the first switch 304 is electrically connected to the positive electrode V+ of the power supply, the other end of the first switch 304 is electrically connected to the airflow component 302, the negative electrode V- of the power supply is electrically connected to the airflow component 302, one end of the second switch 305 is electrically connected to the battery cell monitoring module 101, the other end of the second switch 305 is respectively electrically connected to the negative electrode V- of the power supply and the airflow component 302, one end of the third switch 306 is respectively electrically connected to the battery management system and one end of the second switch 305, the other end of the third switch 306 is electrically connected to the positive electrode of the backup power supply 303, one end of the fourth switch 307 is electrically connected to one end of the third switch 306, the other end of the fourth switch 307 is electrically connected to the airflow component 302, and the negative electrode of the backup power supply 303 is electrically connected to the airflow component 302.

[0088] In this embodiment, the power supply can be provided by the battery pack. When the airflow component 302 needs to be turned on, the battery cell monitoring module 101 controls the first switch 304 and the second switch 305 to be closed, and the power supply is used to power the airflow component 302; when the power supply cannot power the airflow component 302, the battery cell monitoring module 101 controls the third switch 306 and the fourth switch 307 to be closed, so as to realize the use of the backup power supply 303 to power the airflow component 302.

[0089] In some embodiments, the control circuit includes a relay, the relay includes a coil, and the relay is provided with at least four contacts, namely a first contact, a second contact, a third contact and a fourth contact. The first contact and the second contact can be used as a group of normally open contacts and can be understood as a first switch; the coil can be understood as a second switch; the third contact and the fourth contact can be used as a group of normally open contacts and can be understood as a third switch.

[0090] Specifically, one end of the coil is electrically connected to the slave control board of the battery management system, the other end of the coil is electrically connected to the negative pole of the first power supply, the first contact is electrically connected to the positive pole of the first power supply, the second contact is electrically connected to the airflow component, the third contact is electrically connected to one end of the coil and one end of the fourth switch respectively, and the fourth contact is electrically connected to the positive pole of the second power supply.

[0091] When the airflow component needs to be started, the battery management system sends a start signal from the control board to the coil to make the coil conductive, so that the coil closes the first contact and the second contact, and the third contact and the fourth contact, so that the first power supply (which can be understood as the battery pack) and the second power supply (which can be understood as the backup power supply) can simultaneously power the airflow component. When the first power supply and the second power supply power the airflow component at the same time, diodes are provided at the first power supply and the second power supply to prevent current backflow.

[0092] In some embodiments, the present application also provides a battery pack, which includes the thermal runaway management system 10 of the battery pack mentioned in the above embodiments.

[0093] In this embodiment, a battery management system (BMS) is provided in the battery pack, which can ensure that the battery operates safely, reliably and efficiently under various charging and discharging and environmental conditions. The battery management system can extend the service life of the battery and improve its performance by real-time monitoring and management of battery status parameters such as voltage, current, temperature, etc. At the same time, the battery pack can control the thermal runaway management system 10 through the battery management system, which can effectively improve the safety and reliability of the battery pack.

[0094] It can be understood that the thermal runaway management system and battery management system provided in the above embodiments are merely examples. The thermal runaway management system and battery management system described in the embodiments of this application are intended to more clearly illustrate the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. It is known to those skilled in the art that with the evolution of the system and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems. The following are detailed descriptions.

[0095] It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments. The thermal runaway management method is described in detail below. At the same time, the thermal runaway management method provided in this application can be executed by a thermal runaway management system or a battery management system.

[0096] See also Figure 6 , Figure 6 The following is a flow chart of the thermal runaway management method provided in the embodiment of the present application. Figure 6 As shown, the thermal runaway management method includes steps S110 to S130.

[0097] S110, obtaining first temperature information collected by a cell monitoring module at a cell in a battery pack, second temperature information collected by a temperature monitoring circuit at a cell, and first collected information of a fire protection component in the battery pack.

[0098] In the present embodiment, the first temperature information may be the temperature collected by the battery cell monitoring module at the battery cell in the battery pack, the second temperature information may be the temperature collected by the temperature monitoring circuit at the battery cell in the battery pack, and the first collected information may be the smoke information collected by the fire protection component inside the battery pack. Among them, the battery cell monitoring module may be a slave control board of the battery management system, and the temperature monitoring circuit may be a circuit additionally provided in the battery pack for monitoring the temperature of the battery cell. Specifically, the present application may use the battery cell monitoring module to directly obtain the first temperature information, and may also use the temperature monitoring circuit to collect the second temperature information of the battery cell. Through the first temperature information and the second temperature information, not only the accuracy of the temperature finally collected from the battery cell position can be guaranteed, but also after one of them fails, it can ensure that the temperature of the battery cell in a thermal runaway state is obtained.

[0099] When the battery cells in the battery pack are in thermal runaway, the first temperature information, the second temperature information and the first collected information can be obtained, and it can be determined whether at least one of the first temperature information, the second temperature information and the first collected information is abnormal. If abnormal, it can be determined that the battery cells in the battery pack are in thermal runaway, and then the battery cells in thermal runaway can be determined, and thermal runaway treatment can be performed, such as fire extinguishing treatment, to prevent the thermal runaway of the battery cells from spreading to other battery cells, thereby effectively improving the safety and reliability of the battery pack.

[0100] S120: If at least one of the first temperature information, the second temperature information, and the first collected information is abnormal, determine a thermal runaway region in the battery pack.

[0101] In this embodiment, determining the battery cell with thermal runaway in the battery pack specifically refers to determining the location information of the battery cell with thermal runaway in the battery pack. After detecting that at least one of the first temperature information, the second temperature information, and the first collected information is abnormal, the location information of the battery cell with thermal runaway in the battery pack can be determined through at least one of the first temperature information, the second temperature information, and the first collected information. For example, if the first temperature information is abnormal, the location information of the battery cell with thermal runaway in the battery pack can be determined through the circuit corresponding to the first temperature information, or the corresponding second temperature information can be determined through the circuit corresponding to the first temperature information, and the location information of the battery cell with thermal runaway in the battery pack can be determined through the circuit corresponding to the second temperature information.

[0102] In some embodiments, if at least one of the first temperature information, the second temperature information, and the first collected information is abnormal, a thermal runaway area within the battery pack is determined, including: if at least two of the first temperature information, the second temperature information, and the first collected information are abnormal, a thermal runaway area within the battery pack is determined.

[0103] Specifically, in order to ensure that there is no misjudgment of thermal runaway of the battery cell, the present application can determine whether the battery cell in the battery pack is in thermal runaway by determining whether at least two of the first temperature information, the second temperature information, and the first collected information are abnormal, and then determine the thermal runaway area, and perform thermal runaway treatment, such as fire extinguishing treatment, to prevent the thermal runaway of the battery cell from spreading to other battery cells, thereby effectively improving the safety and reliability of the battery pack. For example, if the first temperature information and the second temperature information are abnormal, it can be determined that the battery cell in the battery pack is in thermal runaway; or if the first temperature information and the first collected information are abnormal, it can be determined that the battery cell in the battery pack is in thermal runaway; or if the second temperature information and the first collected information are abnormal, it can be determined that the battery cell in the battery pack is in thermal runaway; or if the first temperature information, the second temperature information, and the first collected information are abnormal, it can be determined that the battery cell in the battery pack is in thermal runaway; or if the first temperature information, the second temperature information, and the first collected information are abnormal, it can be determined that the battery cell in the battery pack is in thermal runaway.

[0104] In some embodiments, the temperature monitoring circuit includes a thermistor; before determining the thermal runaway area in the battery pack, it also includes: if the first temperature information is that the temperature of the battery cell is higher than a preset temperature, determining that the battery cell is in thermal runaway; if the second temperature information is the disconnection information of the thermistor, determining that the battery cell at the thermistor is in thermal runaway; if the first collected information is the preset first information, determining the battery cell in thermal runaway in the battery pack.

[0105] In this embodiment, the temperature monitoring circuit includes multiple thermistors, each battery cell corresponds to a thermistor, the first temperature information is the temperature information monitored by the battery cell monitoring module at the battery cell, if the temperature shows that the temperature of the battery cell is higher than the preset temperature, it can be determined that the battery cell at the corresponding position is thermal runaway; the second temperature information is the on-off information of the thermistor in the temperature monitoring circuit, if the on-off information shows that the thermistor is disconnected, it can be determined that the battery cell at the corresponding position is thermal runaway; the first collected information is the smoke information monitored by the smoke alarm in the fire protection component in the battery pack, if the smoke information shows that the smoke concentration in the battery pack is higher than the preset threshold, that is, the first collected information is the first information, then it can be determined that the battery cell in the battery pack is thermally runaway.

[0106] In some embodiments, the temperature monitoring circuit includes a thermal switch; before determining the thermal runaway area in the battery pack, it also includes: if the first temperature information is that the temperature of the battery cell is higher than a preset temperature, determining whether the second temperature information is the disconnection information of the thermal switch; if the second temperature information is the disconnection information of the thermal switch, determining that the battery cell at the thermal switch is thermally runaway.

[0107] The present application can determine thermal runaway of the battery cell in the battery pack by whether the first temperature information and the second temperature information are abnormal. Specifically, if the first temperature information indicates that the temperature of the battery cell is higher than the preset temperature, it can be determined that the battery cell is likely to be in thermal runaway. In order to avoid misjudgment, it can be determined whether the second temperature information is the disconnection information of the thermal switch, that is, the battery cell monitoring module detects whether there is current or voltage at the thermal switch to determine whether the thermal switch is disconnected. If it is disconnected, it can be determined that the battery cell at the corresponding position is in thermal runaway.

[0108] In some embodiments, before determining the thermal runaway area in the battery pack, it also includes: if the first temperature information indicates that the temperature of the battery cell is higher than a preset temperature, determining whether the first collected information is the preset first information; if the first collected information is the preset first information, determining the battery cell in thermal runaway in the battery pack.

[0109] Specifically, the present application can also determine whether the thermal runaway of the battery cell in the battery pack is abnormal based on the first temperature information and the first collected information. Similarly, if the first temperature information indicates that the temperature of the battery cell is higher than the preset temperature, it can be determined that the battery cell is likely to be in thermal runaway. In order to avoid misjudgment, it can be further determined whether the battery cell is in thermal runaway based on the first collected information of the fire protection component in the battery pack. Specifically, it can be determined whether the first collected information is the preset first information. If it is the first information, it can be determined that the battery cell is in thermal runaway.

[0110] In some embodiments, the temperature monitoring circuit includes a thermistor; before determining the thermal runaway area in the battery pack, it also includes: if the second temperature information is the disconnection information of the thermistor, determining whether the first collected information is the preset first information; if the first collected information is the preset first information, determining the battery cell in thermal runaway in the battery pack.

[0111] Specifically, the present application can also determine whether the thermal runaway of the battery cell in the battery pack is abnormal based on the second temperature information and the first collected information. If the second temperature information is the disconnection information of the thermal switch, it can be determined that the battery cell is likely to be in thermal runaway. In order to avoid misjudgment, it can be further determined whether the battery cell is in thermal runaway based on the first collected information of the fire protection component in the battery pack. Specifically, it can be determined whether the first collected information is the preset first information. If it is the first information, it can be determined that the battery cell is in thermal runaway.

[0112] It should be noted that after obtaining the first temperature information, the second temperature information and the first collection information, the present application can first use any one of them to determine whether thermal runaway occurs in the battery cell. At the same time, in order to further improve the accuracy of thermal runaway, on this basis, the other two or one can be further used for further confirmation.

[0113] In some embodiments, determining a thermal runaway region within a battery pack includes: obtaining location information of a battery cell; and determining the thermal runaway region within the battery pack based on the location information.

[0114] In this embodiment, after determining that a battery cell in thermal runaway has occurred in the battery pack, the thermal runaway area in the battery pack can be directly determined based on the location information of the battery cell, and then the fire-fighting components in the corresponding area can be used to perform fire extinguishing to prevent the thermal runaway of the battery cell from spreading to other battery cells, thereby effectively improving the safety and reliability of the battery pack.

[0115] In some embodiments, determining a thermal runaway area in a battery pack includes: if the first collected information is first information, determining location information of a smoke detector corresponding to the first information; and determining a battery cell in thermal runaway in the battery pack according to the location information.

[0116] In this embodiment, the fire protection component includes multiple smoke detectors, and each battery cell can correspond to a smoke detector. When it is determined that the smoke information shows that the smoke concentration in the battery pack is higher than a preset threshold, that is, the first collected information is the first information, it can be determined that there is a battery cell with thermal runaway in the battery pack. In order to determine the position of the thermal runaway battery cell in the battery pack, the position information of the smoke detector that generates a smoke alarm in the battery pack can be obtained, and then the position of the battery cell with thermal runaway in the battery pack can be determined according to the position information of the smoke detector, so that the fire extinguishing module can be used to extinguish the battery cell with thermal runaway to prevent the thermal runaway of the battery cell from spreading to other battery cells, thereby effectively improving the safety and reliability of the battery pack.

[0117] Furthermore, in some embodiments, determining a battery cell experiencing thermal runaway in a battery pack based on position information includes: acquiring first temperature information and / or second temperature information at a position corresponding to the smoke detector, and determining a battery cell experiencing thermal runaway in the battery pack based on the first temperature information and / or the second temperature information.

[0118] Specifically, the present application can further determine the battery cell in thermal runaway through the first temperature information and / or the second temperature information at the corresponding position of the smoke detector after the smoke detector alarms, so as to avoid misjudgment of thermal runaway, thereby improving the accuracy of determining thermal runaway of the battery cell.

[0119] S130, controlling the fire fighting component to extinguish the fire in the thermal runaway area, and controlling the gas collecting component to collect the gas inside the battery pack.

[0120] Specifically, after determining that the battery cells in the battery pack have thermal runaway and the thermal runaway area, the fire-fighting component can be controlled to extinguish the fire in the thermal runaway area, and the gas collection component can be controlled to collect the gas inside the battery pack. This can not only timely control the spread of thermal runaway in the battery pack, but also can promptly process the exhaust gas generated by the thermal runaway after the battery cell triggers thermal runaway, effectively improving the safety and reliability of the battery pack.

[0121] In some embodiments, the temperature monitoring circuit includes multiple thermistors, each battery cell corresponds to a thermistor, the battery pack is provided with a ventilation valve, and the gas collection component includes an airflow component and a gas collection pipe; wherein, controlling the gas collection component to collect gas inside the battery pack includes: starting the airflow component to reduce the pressure inside the gas collection pipe; after a preset first time, obtaining the on-off information of the thermistor at the battery cell in the battery pack where thermal runaway has not occurred; if the on-off information is the disconnection information of the thermistor, opening the ventilation valve to discharge the gas in the battery pack through the ventilation valve and the gas collection pipe in sequence.

[0122] In this embodiment, the gas collection pipe is arranged outside the battery pack, one end of the air valve is connected to one end of the gas collection pipe, the airflow component is arranged at the other end of the gas collection pipe, and the other end of the air valve is connected to the inside of the battery pack.

[0123] In the process of controlling the gas collection component to collect the gas inside the battery pack, the airflow component can be started first to reduce the pressure inside the gas collection pipe. Due to thermal runaway of the battery cells in the battery pack, the pressure inside the battery pack is relatively high. Therefore, a large pressure difference can be formed on both sides of the air valve, making it easier to open the air valve to quickly discharge the harmful gases generated in the battery pack.

[0124] At the same time, since thermal runaway may spread in the battery pack, and when thermal runaway spreads in the battery pack, the vent valve may still be in an unopened state, it is also necessary to confirm whether the battery cells that have not experienced thermal runaway in the battery pack have experienced thermal runaway after a preset first time. The battery cell monitoring module may not be able to monitor the status of other battery cells that have not experienced thermal runaway. For this reason, the present application preferably determines whether the battery cells that have not experienced thermal runaway have experienced thermal runaway through the on-off information of the thermistor at the battery cells that have not experienced thermal runaway, and then determines whether the thermal runaway has spread to other battery cells. If the thermistor at the battery cell that has not experienced thermal runaway is disconnected, it can be determined that the thermal runaway has spread to other battery cells. At this time, the vent valve needs to be opened immediately so that the gas in the battery pack can be quickly and timely discharged from the vent valve and the gas collection pipe in sequence.

[0125] Among them, the air valve is a device used to balance the pressure inside and outside the sealed equipment to prevent the entry of moisture, dust and other contaminants. Its main function is to maintain good air permeability while preventing the intrusion of water droplets, drizzle, fine impurities and chemicals.

[0126] In some embodiments, the gas collection assembly 300 further includes a control circuit, and the control circuit includes a first switch; starting the airflow assembly includes: controlling the first switch to close to turn on the airflow assembly.

[0127] Specifically, the present application preferably selects a battery pack to provide power for the airflow component, that is, the battery pack can be used to power the airflow component by controlling the first switch to be closed, thereby turning on the airflow component, so that the gas generated by thermal runaway inside the battery pack can be discharged in a direction.

[0128] In some embodiments, the gas collection component 300 also includes a breathable valve, and the control circuit also includes a second switch, a third switch and a fourth switch; wherein, controlling the first switch to close to turn on the airflow component includes: controlling the second switch to be in a powered-on state; and according to the powered-on second switch, controlling the first switch and the third switch to close to turn on the airflow component.

[0129] In this embodiment, the gas collection component 300 is also provided with a second power supply, i.e., a backup power supply, and the control circuit includes a relay and a fourth switch. The coil of the relay can be used as the second switch, and the relay is provided with at least two groups of normally open contacts, one group of normally open contacts is used as the first switch, and the other group of normally open contacts can be used as the third switch. When the battery management system controls the coil to conduct electricity, the first switch and the third switch are closed. At this time, since the fourth switch is provided between the positive electrode of the second power supply and the airflow component, the fourth switch can be in an open state first, so that the battery pack supplies power to the airflow component.

[0130] After controlling the first switch and the third switch to close to open the airflow component, if the battery pack cannot supply power to the airflow component due to thermal runaway, the fourth switch can be closed to open the air valve and the airflow component.

[0131] It should be noted that the reason why the other group of normally open contacts of the relay can be used as the third switch in the present application is mainly to enable the second power supply to continuously energize the coil of the relay through the third switch after the third switch is closed. This not only enables the first power supply to power the airflow component through the first switch, but also enables the second power supply to continuously power the airflow component through the third switch, thereby ensuring that the airflow component will not be powered off when in the on state.

[0132] It can be understood that the present application can also directly control the fourth switch to close while energizing the coil of the relay to control the first switch and the third switch to be turned on, so as to open the valve of the air valve in advance, thereby enabling the first power supply and the second power supply to power the airflow component at the same time.

[0133] In some embodiments, after the ventilation valve is opened to discharge the gas in the battery pack through the ventilation valve and the gas collection pipe in sequence, it also includes: after a preset second time, obtaining second collection information of the fire protection component in the battery pack; if the second collection information is the preset second information, opening the balancing valve, and controlling the airflow component to stop working.

[0134] In this embodiment, the second collected information may be the smoke information collected by the fire protection component inside the battery pack. After the second time, the second collected information is the second information, the balancing valve is opened, and the airflow component is controlled to stop working. Among them, the second information is the information that the smoke concentration in the battery pack does not exceed the preset concentration. If the second collected information is the second information, it can be determined that the thermal runaway of the battery cell in the battery pack is controlled.

[0135] Among them, the second information may be information that the smoke concentration in the battery pack is lower than a preset concentration, that is, when the second collected information in the battery pack is that the smoke concentration in the battery pack is lower than the preset concentration, the balancing valve may be opened to balance the air pressure inside and outside the battery pack to avoid secondary damage to the battery pack; at the same time, the second information may also be information that the air pressure in the battery pack is lower than the preset air pressure, that is, when the first collected information in the battery pack is that the air pressure in the battery pack is lower than the preset air pressure, it can be determined that basically no gas is generated in the battery pack. At this time, the battery pack body has reached its limit, and the body is about to be deformed, so it is necessary to open the balancing valve to balance the air pressure inside and outside the battery pack to avoid secondary damage to the battery pack.

[0136] At the same time, after determining that the battery cell with thermal runaway is under control, the present application can open the balancing valve and control the airflow component to stop working, so as to adjust the air pressure inside the battery pack and prevent the battery pack from deforming and suffering secondary damage. Among them, the balancing valve is arranged on the box where the battery pack is located and is connected to the inside of the battery pack. The balancing valve can be divided into three types: static balancing valve, dynamic balancing valve and pressure difference independent balancing valve.

[0137] The thermal runaway management method provided in the present application obtains the first temperature information of the battery cell monitoring module at the battery cell in the battery pack, the second temperature information of the temperature monitoring circuit at the battery cell and the first collected information of the fire protection component in the battery pack. When at least one of the first temperature information, the second temperature information and the first collected information is abnormal, the thermal runaway area in the battery pack is determined, and the fire protection component is controlled to extinguish the fire inside the battery pack and the gas collection component is controlled to collect the gas inside the battery pack. This not only realizes the monitoring of the thermal runaway of the battery cell, but also can timely control the spread of the thermal runaway in the battery pack, and after other battery cells trigger thermal runaway, the exhaust gas generated by the thermal runaway can be processed in time, thereby effectively improving the safety and reliability of the battery pack.

[0138] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A thermal runaway management method, characterized in that: Applied to a battery pack, the battery pack includes a thermal runaway management system, the thermal runaway management system includes a battery cell monitoring module, a temperature monitoring circuit, a fire protection component and a gas collection component; the method includes: Acquire first temperature information collected by the battery cell monitoring module at the battery cell in the battery pack, second temperature information collected by the temperature monitoring circuit at the battery cell, and first collected information of the fire protection component in the battery pack; If at least one of the first temperature information, the second temperature information, and the first collected information is abnormal, determining a thermal runaway area in the battery pack; The fire fighting component is controlled to perform fire extinguishing at the thermal runaway region, and the gas collecting component is controlled to collect gas inside the battery pack.

2. The thermal runaway management method according to claim 1, characterized in that: The temperature monitoring circuit includes a thermal switch; Wherein, before determining the thermal runaway region in the battery pack, the method further includes: If the first temperature information indicates that the temperature of the battery cell is higher than a preset temperature, determining whether the second temperature information is disconnection information of the thermal switch; If the second temperature information is the disconnection information, it is determined that the battery cell at the thermal switch is in thermal runaway.

3. The thermal runaway management method according to claim 1, characterized in that: The temperature monitoring circuit includes a thermal switch; Wherein, before determining the thermal runaway region in the battery pack, the method further includes: If the first temperature information indicates that the temperature of the battery cell is higher than a preset temperature, determining whether the first collected information is the preset first information; If the first collected information is the preset first information, it is determined that the battery cell is in thermal runaway.

4. The thermal runaway management method according to claim 1, characterized in that: The temperature monitoring circuit includes a thermal switch; Wherein, before determining the thermal runaway region in the battery pack, the method further includes: If the second temperature information is disconnection information of the thermal switch, determining whether the first collected information is the preset first information; If the first collected information is the preset first information, it is determined that the battery cell is in thermal runaway.

5. The thermal runaway management method according to claim 1, characterized in that: The determining of the thermal runaway region in the battery pack includes: Obtaining location information of the battery cell; A thermal runaway region within the battery pack is determined according to the position information.

6. The thermal runaway management method according to any one of claims 1 to 5, characterized in that: The temperature monitoring circuit includes a plurality of thermal switches, each of the battery cells corresponds to one thermal switch, the battery pack is provided with a vent valve, and the gas collection component includes an airflow component and a gas collection pipeline; Wherein, controlling the gas collection assembly to collect gas inside the battery pack includes: activating the gas flow assembly to reduce the pressure inside the gas collection pipeline; After a preset first time, obtaining on / off information of the thermal switch at a battery cell in the battery pack where no thermal runaway occurs; If the on-off information is disconnection information of the thermal switch, the ventilation valve is opened to discharge the gas in the battery pack through the ventilation valve and the gas collection pipe in sequence.

7. The thermal runaway management method according to claim 6, characterized in that: The battery pack is also provided with a balancing valve; Wherein, after the ventilation valve is opened to discharge the gas in the battery pack through the ventilation valve and the gas collection pipe in sequence, the method further includes: After a preset second time, obtaining second collected information of the fire protection component in the battery pack; If the second collected information is the preset second information, the balancing valve is opened, and the airflow component is controlled to stop working.

8. A thermal runaway management system, characterized in that: include: A battery cell monitoring module is disposed inside the battery pack and electrically connected to the battery cells in the battery pack; A temperature monitoring circuit is disposed inside the battery pack and electrically connected to the battery cell monitoring module, wherein the temperature monitoring circuit is configured to monitor the temperature of the battery cell; A fire protection component, disposed inside the battery pack and electrically connected to the battery monitoring circuit; a gas collection assembly, electrically connected to the battery monitoring circuit and in communication with the interior of the battery pack; Wherein, the battery cell monitoring module is at least configured to monitor the temperature of the battery cell, and control the fire fighting component to perform fire extinguishing inside the battery pack, and at the same time control the gas collection component to collect gas inside the battery pack.

9. The thermal runaway management system according to claim 8, characterized in that: The temperature monitoring circuit comprises a thermal switch; one end of the thermal switch is electrically connected to the battery cell, and the other end of the thermal switch is electrically connected to the temperature monitoring circuit.

10. A battery pack, characterized in that: A thermal runaway management system for a battery pack comprising the method of claim 9.

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