System and method for detecting battery module and processing battery cell thermal runaway fault

Abstract

The invention relates to the field of new energy power system energy storage and new energy automobiles, in particular to a system and method for detecting a battery module and processing a thermal runaway fault of a battery cell, and the system comprises a sensing resistor which is used for detecting the surface temperature of the battery cell; the circuit board is used for fixing the sensing resistors and connecting all the sensing resistors in series; the fault detection module is used for detecting the resistance state of the sensing resistor and outputting a turn-off signal at the same time; the control module is used for receiving the turn-off signal output by the fault detection module and sending a control signal to the driving module; and the driving module is used for receiving the turn-off signal output by the fault detection module and the control signal output by the control module, and outputting a driving signal after processing. According to the battery module, each battery cell in the battery module is correspondingly provided with at least one sensing resistor, so that the thermal runaway fault of each battery cell can be effectively detected, and the delay of a traditional battery cell temperature detection scheme is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the field of new energy power system energy storage and new energy vehicles, and in particular to a system and method for detecting battery modules and processing battery core thermal runaway faults. Background Art

[0002] With the continuous development of modern science and technology, battery technology is increasingly used in various fields. In many application scenarios, such as electric vehicles, large container energy storage, industrial and commercial energy storage, data center base station energy storage, etc., in order to improve energy storage density and meet power requirements, it is often necessary to use multiple battery packs in series and parallel. In these application scenarios, the number of battery cells ranges from dozens to thousands, and the number of battery packs ranges from a few to hundreds. The thermal runaway of any battery pack or even battery cell will cause system failure or even paralysis, and serious and even catastrophic accidents. In the new energy storage industry and the new energy vehicle industry, the thermal runaway safety problem of the battery system has always been a technical problem that has plagued the entire industry.

[0003] The traditional method of detecting the temperature of the battery cell inside the battery module is to install an NTC thermistor on or near the aluminum palladium of the battery cell electrode, and indirectly measure the temperature of the battery cell by measuring the temperature of the aluminum palladium. This solution has the following problems: ① The measured temperature of the battery cell is greatly different from the internal temperature of the battery cell; ② When the battery cell thermally runs away, the measured temperature has a serious delay; ③ The temperature of each battery cell cannot be measured. The main reasons for the above problems are: ① The resistance of the NTC thermistor changes slowly with temperature, and there is a certain delay; ② The same aluminum palladium is connected to the electrodes of two battery cells at the same time, and it is impossible to measure the temperature of each battery cell; ③ The heat dissipation performance of the aluminum palladium is too large, resulting in a large part of the heat conducted by the electrode being eliminated; ④ When the battery cell thermally runs away, there is a problem of slow temperature rise at the electrode position.

[0004] Publication number: CN214957256U A fast-joined cell connection and voltage and temperature acquisition component and a power battery, comprising at least two isolation plates and at least one connecting piece, which are arranged on the isolation plates along the length direction of the component. The component also comprises a plurality of temperature acquisition components, which are arranged on the isolation plates, and each of the temperature acquisition components is connected to each of the cells and used to detect the temperature of the cells. The component also comprises a flexible circuit board, which is extended along the length direction of the component and arranged on each isolation plate, and the flexible circuit board is electrically connected to each connecting piece. This invention effectively collects the operating temperature of each cell by arranging the temperature acquisition component on the isolation plate, but there are still problems such as temperature sensing delay, poor system safety in thermal runaway state, and slow control response as the number of cells increases.

[0005] Against the backdrop of growing energy demand and increasing safety requirements for battery systems, there is an urgent need for a method with innovative functions for rapid detection, reporting and processing of thermal runaway faults to address the problems of delayed cell temperature detection and poor system safety in thermal runaway states in existing technologies, providing new ideas and solutions for the development and application of battery technology. Summary of the invention

[0006] In view of this, the present invention aims to propose a system and method for detecting and processing thermal runaway failures of battery modules, so as to solve the problems of delayed temperature detection of battery cells and poor safety of thermal runaway systems in the prior art.

[0007] The technical solution of the present invention is achieved in this way:

[0008] The present invention discloses a system for detecting and processing thermal runaway failures of battery modules, comprising:

[0009] A plurality of sensing resistors, wherein the resistance value of the sensing resistor changes with temperature, and the sensing resistor is used to detect the temperature change of the surface of the corresponding battery cell;

[0010] The circuit board is used to fix the sensing resistors and connect all the sensing resistors;

[0011] The fault detection module is used to detect the resistance state of the sensing resistor and output a shutdown signal;

[0012] The control module is used to receive the shutdown signal output by the fault detection module and send a control signal to the driving module;

[0013] The driving module is used to receive the shutdown signal output by the fault detection module and the control signal output by the control module, and output the driving signal after processing, or the driving module directly outputs the driving signal according to the shutdown signal to control the power module;

[0014] The power module is used to receive the driving signal output by the driving module and execute the switching on and off of the power circuit.

[0015] Furthermore, one surface or multiple surfaces of each battery cell are provided with the sensing resistor.

[0016] Furthermore, the sensing resistor is a nonlinear positive temperature coefficient sensing resistor or a nonlinear negative temperature coefficient sensing resistor.

[0017] Furthermore, the circuit board is a flexible circuit board, and a terminal of the circuit board is provided with two output pins for detecting the resistance states of all the sensing resistors after being connected.

[0018] Furthermore, the sensing resistors are welded on the circuit board, and all the sensing resistors are connected in series, in parallel, or in series-parallel, and are connected to two output pins of the circuit board terminal.

[0019] Furthermore, the fault detection module is a detection circuit for detecting the resistance between the output pins of the circuit board, and outputting a shutdown signal to the control module and the drive module according to the resistance state detected between the output pins of the circuit board.

[0020] Furthermore, the fault detection module includes a first resistor R1, a second resistor R2, a third resistor R3 and an optocoupler U1, one end of the third resistor R3, the circuit board and pin a of the optocoupler U1 are connected in series in sequence, the other end of the third resistor R3 is connected to the power supply VCC1, the pin b of the optocoupler U1 is grounded, the pin c of the optocoupler U1 is connected to the power supply VCC2, the pin d of the optocoupler U1 is respectively connected to one end of the first resistor R1 and the second resistor R2, the other end of the first resistor R1 is respectively connected to the control module and the drive module, and the other end of the second resistor R2 is grounded.

[0021] Furthermore, the power module is a power switch circuit, which turns on the power circuit when the received driving signal is valid, otherwise the power circuit is turned off.

[0022] The present invention discloses a method for detecting and processing a thermal runaway fault of a battery module. The method for detecting and processing a thermal runaway fault of a battery module comprises the following steps when the sensing resistor is a nonlinear positive temperature coefficient sensing resistor:

[0023] S1: The sensing resistor detects the surface temperature of the corresponding battery cell in real time, and the fault detection module detects the output resistance state of the circuit board;

[0024] S2: When the fault detection module detects that the output resistance state of the circuit board is in a high resistance state, execute step S3; when the fault detection module detects that the output resistance state of the circuit board is in a low resistance state, execute step S4;

[0025] S3: the fault detection module outputs a low-level shutdown signal to the control module and the drive module, the drive module outputs a low-level drive signal to control the power module to disconnect, and the control module records the time and information of the thermal runaway event and issues an alarm, and then executes step S11;

[0026] S4: the fault detection module outputs a high-level shutdown signal to the control module, and the control module determines whether there is a thermal runaway record within the previous period T. If yes, execute step S5; if no, execute step S8;

[0027] S5: Acquire the temperature of the battery cell, and the control module determines whether the temperature of the battery cell is greater than or equal to the set recovery temperature. If yes, execute step S6; if no, execute step S8;

[0028] S6: The control module outputs a low-level control signal and issues an alarm that the recovery temperature has not been reached;

[0029] S7: after receiving the low-level control signal, the driving module outputs a low-level driving signal to control the power module to be disconnected, and executes step S10;

[0030] S8: the control module outputs a high level control signal to the driving module;

[0031] S9: after receiving the high-level control signal, the driving module outputs a high-level driving signal to control the power module to be turned on, and step S1 is executed;

[0032] S10: After time t1 has passed or the temperature of the battery cell is continuously detected, step S5 is executed;

[0033] S11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step S1.

[0034] The present invention discloses a method for detecting and processing a thermal runaway fault of a battery module. The system for detecting and processing a thermal runaway fault of a battery module, when the sensing resistor is a nonlinear negative temperature coefficient sensing resistor, specifically comprises the following steps:

[0035] ST1: The sensing resistor detects the surface temperature of the corresponding battery cell in real time, and the fault detection module detects the output resistance state of the circuit board;

[0036] ST2: When the fault detection module detects that the output resistance state of the circuit board is in a low resistance state, execute step ST3; when the fault detection module detects that the output resistance state of the circuit board is in a high resistance state, execute step ST4;

[0037] ST3: the fault detection module outputs a high-level shutdown signal to the control module and the drive module, the drive module outputs a high-level drive signal to control the power module to disconnect, and the control module records the time and information of the thermal runaway event and issues an alarm, and executes step ST11;

[0038] ST4: The fault detection module outputs a low-level shutdown signal to the control module, and the control module determines whether there is a thermal runaway record within the previous period T. If yes, execute step S5; if no, execute step ST8;

[0039] ST5: Obtain the temperature of the battery cell, and the control module determines whether the temperature of the battery cell is greater than or equal to the set recovery temperature. If yes, execute step ST6; if no, execute step ST8;

[0040] ST6: The control module outputs a high-level control signal and issues an alarm that the recovery temperature has not been reached;

[0041] ST7: After receiving the high-level control signal, the driving module outputs a low-level driving signal to control the power module to be disconnected, and executes step ST10;

[0042] ST8: The control module outputs a low-level control signal to the driving module;

[0043] ST9: After receiving the high-level control signal, the driving module outputs a high-level driving signal to control the power module to be turned on, and executes step ST1;

[0044] ST10: After time t1 has passed or the temperature of the battery cell is continuously detected, step ST5 is executed;

[0045] ST11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step ST1.

[0046] Compared with the prior art, the system and method for detecting and processing thermal runaway failure of a battery module of the present invention has the following advantages:

[0047] 1. The present invention performs comprehensive temperature monitoring on the surface of each battery cell through a sensing resistor, thereby improving the accuracy and reliability of detection. The fault detection module directly feeds back to the drive module, and uses hardware signals to directly disconnect the power circuit within milliseconds, which significantly shortens the response time and enhances the safety of the system. At the same time, the control module and the fault detection module work together to ensure that the system can respond in time under abnormal circumstances, and prevent frequent switching by setting the recovery temperature, thereby extending the battery life.

[0048] 2. By setting at least one sensing resistor for each battery cell in the battery module, the thermal runaway failure of each battery cell can be effectively detected, effectively reducing the delay of the traditional battery cell temperature detection solution. The temperature on the surface of the battery cell is closer to the temperature inside the battery cell than the temperature at the aluminum-palladium position of the battery cell electrode, which helps to improve the accuracy of thermal runaway detection of the battery cell.

[0049] 3. Compared with the traditional battery cell temperature detection scheme, when the present invention detects a battery cell thermal runaway fault, even in the case of software failure, the power circuit can be directly disconnected through the hardware circuit, and the fault can be reported in a shorter time, so that the main control can control other components to take protective actions in a shorter time.

[0050] 4. Compared with the traditional battery cell temperature detection scheme, the present invention realizes a double verification mechanism by combining the hardware-level protection of the fault detection module and the software-level control of the control module, thereby enhancing the reliability and safety of the system and introducing a temperature stability check function to ensure that the power module will be turned on again only when the battery cell temperature is truly restored to a safe range, thereby avoiding frequent switching due to temperature fluctuations, immediately cutting off the power supply at the moment of thermal runaway, and restarting only after confirming that the fault has been eliminated and the temperature has returned to normal, reflecting the innovative design of rapid response and intelligent recovery.

[0051] 5. Compared with the traditional battery cell temperature detection scheme, the present invention can use multiple nonlinear positive temperature coefficient resistors in series, which is simpler to install. There is no need to continuously detect multiple nonlinear positive temperature coefficient resistors, and fewer IO resources of the main control are occupied. The delay of data collection, reporting, and protection will not be affected as the number of battery cells increases, so that the real-time detection, reporting, and processing of thermal runaway faults are not affected by the number of battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0053] Figure 1 A schematic diagram of a method for quickly detecting and handling thermal runaway failures of battery modules;

[0054] Figure 2 This is a schematic diagram of the sensing resistor installation;

[0055] Figure 3 Schematic diagram of the fault detection module.

[0056] Description of reference numerals:

[0057] 1. Sensing resistor; 2. Circuit board; 3. Fault detection module; 4. Control module; 5. Drive module; 6. Power module. DETAILED DESCRIPTION

[0058] In order to make the technical means, objectives and effects of the present invention easy to understand, the embodiments of the present invention are described in detail below with reference to specific drawings.

[0059] It should be noted that all the terms used in the present invention to indicate directionality and positionality, such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inside", "outside", "top", "lower", "lateral", "longitudinal", "center", etc., are only used to explain the relative positional relationship and connection status between the components in a certain state, and are only for the convenience of describing the present invention, rather than requiring the present invention to be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features.

[0060] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0062] There are generally two existing methods for detecting and handling thermal runaway faults: first, the temperature near the battery cell or the bus temperature is detected by a thermistor. When the temperature is detected to be higher than the set value, the signal will be transmitted to a unified control module, and the control module will cut off the current through logical judgment; all judgments of this method need to be made by the control module, and the processing flow is relatively long. If it is in a normal state, it will not affect the handling of the fault, but the battery in a thermal runaway state must be handled quickly, otherwise, it is easy to cause a chain reaction of multiple batteries, especially when the communication of the control module is terminated, which is easy to cause a greater danger; second, when the circuit current is abnormal, the battery unit current is cut off by a fuse or an automatic circuit breaker. The premise of this method is that the circuit current is abnormal, rather than directly detecting the temperature. There are many interference factors, such as short-term abnormal current, short circuit after a battery thermal runaway, etc. The judgment of battery thermal runaway is not accurate enough, and the degree of automation is insufficient, and the specific status of the battery cannot be monitored.

[0063] In order to shorten the reporting and processing time of thermal runaway faults, a method for rapid detection and processing of thermal runaway faults of battery cells suitable for battery modules has emerged.

[0064] Setting a sensing resistor on the surface of each battery cell, directly disconnecting the power circuit through hardware circuits and formulating a new thermal runaway processing method can effectively solve the problem of long detection, reporting and processing cycles of thermal runaway faults in traditional battery modules: ① When any battery cell thermal runaway causes the surface temperature to exceed the standard, the fault will be reported within milliseconds and the power circuit of the battery module will be disconnected. ② The detection, reporting and processing cycle of thermal runaway faults is not affected by the number of batteries under its jurisdiction.

[0065] The present invention has an innovative method for quickly detecting, reporting and processing thermal runaway faults, has multiple safety protection functions, effectively shortens the reaction process when a fault occurs, reduces the time required for judgment, and ensures that the battery cell resumes power supply in a safe state.

[0066] When multiple battery cells are packaged together in the same outer shell frame and connected to the outside through a unified boundary, this forms a battery module.

[0067] In the present invention, the normal temperature state is the temperature not higher than 150°C, and the detected cell surface temperature greater than or equal to 150°C is a thermal runaway state or a temperature abnormal state. The recovery temperature is set to 45°C, and the system can only be powered on when the detected cell temperature is lower than the set recovery temperature.

[0068] An object of the present invention is to disclose a system for quickly detecting and processing thermal runaway failures of battery modules, comprising:

[0069] A plurality of sensing resistors 1, the resistance value of the sensing resistor 1 changes with temperature, and the sensing resistor 1 is used to detect the temperature change of the surface of the corresponding battery cell;

[0070] The circuit board 2 is used to fix the sensing resistor 1 and connect all the sensing resistors 1;

[0071] The fault detection module 3 is used to detect the resistance state of the sensing resistor 1 and output a shutdown signal;

[0072] The control module 4 is used to receive the shutdown signal output by the fault detection module 3 and send a control signal to the drive module 5;

[0073] The driving module 5 is used to receive the shutdown signal output by the fault detection module 3 and the control signal output by the control module 4, and output the driving signal after processing, or the driving module 5 directly outputs the driving signal to control the power module 6 according to the shutdown signal;

[0074] The power module 6 is used to receive the driving signal output by the driving module 5 and execute the switching on and off of the power circuit.

[0075] The sensing resistor 1 is fixed at the key position of each battery cell to ensure that the main heating area of ​​the battery cell is covered. The sensing resistor 1 is fixed in series on the surface of the battery cell using the circuit board 2 to ensure good contact and signal transmission. Compared with the traditional battery cell temperature detection solution, as the number of battery cells increases, the delay of data collection, reporting, and protection will also increase. This solution connects the sensing resistor 1 in series, so that the real-time detection, reporting, and processing of thermal runaway faults are not affected by the number of battery cells; the fault detection module 3 continuously monitors whether the total resistance of all sensing resistors 1 changes, and then whether the resistance state changes. The fault detection module 3 can be directly connected to the drive module 5, disconnect the power circuit through the hardware signal, and realize the shutdown of the power module 6 within milliseconds to ensure a quick response. The control module 4 receives the shutdown signal of the fault detection module 3, reports the fault status, and notifies the remote monitoring center or other management systems. At the same time, the control module 4 sends a control signal to the drive module 5 to ensure that the drive module 5 can accurately execute the action of cutting off or restoring the power circuit. The control module 4 presets a safe recovery temperature. When the battery cell temperature drops below this temperature, it automatically sends an effective control signal to turn on the power circuit. By setting a reasonable recovery temperature, the battery cells can be prevented from frequently turning on and off near the critical temperature of thermal runaway, thus protecting the safety and stability of the battery module.

[0076] This setting performs comprehensive temperature monitoring on the surface of the battery cell through the sensing resistor 1, which improves the accuracy and reliability of the detection, and directly disconnects the power circuit using the hardware signal, which significantly shortens the response time and enhances the safety of the system. At the same time, the control module 4 works together with the fault detection module 3 to ensure that the system can respond promptly under abnormal circumstances, and prevents frequent switching by setting the recovery temperature, thereby extending the battery life.

[0077] Specifically, it also includes a communication module and an alarm module. The communication module is used for information transmission between various components in the system, and the alarm module is used for early warning of faults.

[0078] Specifically, a sensing resistor 1 is disposed on one or more surfaces of each battery cell. Under normal circumstances, the resistance of the sensing resistor 1 is approximately 0 ohm, that is, between 1 mΩ and 1Ω.

[0079] One or more surfaces of each battery cell are provided with a sensing resistor 1 to ensure accurate temperature monitoring of key positions of each battery cell. Each battery cell has an independent sensing resistor 1. Even if a single battery cell has a problem, it will not affect the monitoring accuracy and reliability of other battery cells, thereby increasing the redundancy of the system and improving the overall safety and reliability, ensuring that all key areas of the entire battery module can be effectively monitored and reducing monitoring blind spots. The sensing resistor 1 provides real-time feedback on temperature changes on the surface of the battery cell, and can capture abnormal temperature rise at an early stage.

[0080] The temperature on the surface of the battery cell is closer to the temperature inside the battery cell than the temperature at the aluminum-palladium position of the battery cell electrode. Compared with the traditional battery cell temperature detection scheme, the battery cell temperature can be detected more accurately, thereby improving the accuracy of battery cell thermal runaway detection.

[0081] Under normal circumstances, the resistance of the sensing resistor 1 is about 0 ohms, which means that the sensing resistor 1 has little effect on the circuit under normal working conditions and hardly introduces additional voltage drop or current loss. When the temperature rises, the resistance of the sensing resistor 1 increases rapidly, and the temperature change can be detected sensitively, especially when approaching the critical point of thermal runaway, causing the resistance of the entire circuit to change, so that abnormal temperature rise can be detected quickly.

[0082] This setting achieves accurate monitoring and rapid response to the temperature of the battery cells in the battery module by setting at least one sensing resistor 1 on the surface of each battery cell, and the resistance of these sensing resistors 1 is about 0 ohms under normal circumstances, which not only improves the accuracy and reliability of the system, but also enhances safety and flexibility.

[0083] Specifically, the sensing resistor 1 may be a nonlinear positive temperature coefficient sensing resistor, or may be other sensing devices with a positive temperature coefficient or a negative temperature coefficient whose resistance changes with temperature.

[0084] Nonlinear positive temperature coefficient sensing resistor, that is, nonlinear positive temperature coefficient thermistor, as the resistance value increases with the temperature. When the nonlinear positive temperature coefficient sensing resistor detects that the temperature reaches above the set temperature, the resistor is in a high resistance state; when the nonlinear positive temperature coefficient sensing resistor detects that the temperature reaches below the set temperature, the resistor is in a low resistance state.

[0085] Nonlinear negative temperature coefficient sensing resistor, that is, nonlinear negative temperature coefficient thermistor, as the resistance value decreases with the increase of temperature. When the nonlinear negative temperature coefficient sensing resistor detects that the temperature reaches above the set temperature, the resistor is in a low resistance state; when the nonlinear negative temperature coefficient sensing resistor detects that the temperature reaches below the set temperature, the resistor is in a high resistance state.

[0086] Whether it is a nonlinear positive temperature coefficient PTC sensing resistor, or other positive temperature coefficient PTC or negative temperature coefficient NTC sensing devices, the most suitable type can be selected according to actual needs. All types of sensing resistors 1 can provide real-time feedback on the temperature changes on the surface of the battery cell and can capture abnormal temperature rise at an early stage.

[0087] The nonlinear positive temperature coefficient resistor has a shorter action time, and the temperature rise rate of the battery surface is faster than that of the battery electrode aluminum palladium, which effectively reduces the delay of the traditional battery temperature detection solution. The nonlinear PTC resistor increases rapidly when the temperature rises, which is particularly suitable for thermal runaway warning and can provide a highly sensitive response when the temperature approaches the critical point.

[0088] The resistance of a linear PTC resistor increases linearly with temperature and is suitable for applications that require continuous and stable temperature monitoring.

[0089] The resistance of NTC resistors decreases as the temperature increases. They are suitable for applications that require monitoring over a wide temperature range and can provide finer temperature resolution.

[0090] The setting of different types of sensing resistors 1 can provide the most suitable temperature measurement accuracy according to specific needs, ensure accurate grasp of the state of each battery cell, and select the appropriate type of sensing resistor 1 to ensure stable operation under various temperature environments, thereby improving the reliability of the system.

[0091] Specifically, the circuit board 2 is a flexible circuit board or other materials with similar flexibility and conductive properties. The circuit board 2 has two output pins at its terminal, and the resistance between the two output pins is the resistance state of all the sensing resistors 1.

[0092] Flexible circuit boards or other materials with similar flexibility and conductive properties can fit closely to the surface of the battery cell, ensuring that they fit closely to the surface of the battery cell and improving the accuracy of temperature detection. Other materials with similar flexibility and conductive properties, such as flexible conductive fabrics or flexible printed electronic materials, use other flexible substrates, such as polyimide films, etc.

[0093] All sensing resistors 1 are connected in series, so that the total resistance between the two pins is the accumulation of the resistance values ​​of all sensing resistors 1, which means that any change in the resistance value of any sensing resistor 1 will be reflected in the total resistance, thereby realizing overall monitoring of the temperature status of the entire battery module, and then outputting the total resistance value through two pins, simplifying the design of the external detection circuit and reducing the complexity of wiring.

[0094] This setting improves the accuracy and timeliness of temperature detection, simplifies the installation process, reduces connection points, and greatly reduces the failure rate, while the two-pin output design is easy to integrate with other monitoring and control systems, facilitating subsequent expansion and upgrading.

[0095] Specifically, the sensing resistor 1 is welded on the circuit board 2, and the circuit board 2 is fixed to the surface of the battery cell by adhesive or other means.

[0096] The sensing resistor 1 is directly soldered on the circuit board 2, which ensures the reliability of the electrical connection and reduces the risk of poor contact. The soldering point provides mechanical strength, so that the entire sensor assembly can still maintain stable operation under vibration or impact environment.

[0097] Through adhesive backing or other fixing methods, the circuit board 2 can fit tightly to the surface of the battery cell, which can better fix the circuit board 2, prevent the displacement of the circuit board 2, and avoid the circuit board 2 exerting a force parallel to the surface of the battery cell on the sensing resistor 1, effectively improving the reliability and stability of the system.

[0098] Specifically, all the sensing resistors 1 are connected in series, in parallel, or in series-parallel, and are connected to a terminal of the circuit board 2 provided with two output pins.

[0099] The series connection adds the resistance of all the sense resistors to form a total high resistance. When the temperature of any cell rises, the corresponding sense resistor increases, causing the total resistance to change significantly, making it easier to detect. Any change in a single resistor will significantly affect the total resistance, making the system very sensitive to temperature changes.

[0100] After connecting multiple resistors in parallel, the total resistance will be smaller than any single resistor, and the current will disperse through each resistor, reducing the current pressure on a single resistor. If one resistor fails, the other resistors can still continue to work, improving the fault tolerance of the system. Due to the small total resistance, the system can respond quickly to temperature changes at a lower voltage. The parallel structure usually has a lower total resistance, reducing power consumption.

[0101] The series-parallel combination connection can flexibly configure the number and connection method of resistors according to specific needs, optimize the performance of the resistor network, and combine the advantages of series and parallel connections to improve sensitivity and enhance redundancy. Through a reasonable series-parallel combination, the best balance between sensitivity and redundancy can be found. It is easy to expand and can add more resistors as needed to adapt to battery modules of different sizes. By adjusting the ratio of series-parallel, the total resistance value can be accurately controlled to achieve more sophisticated temperature monitoring and protection.

[0102] This setting can significantly improve the performance of the battery module detection and processing system for thermal runaway failures by properly selecting series, parallel or series-parallel connection. This design not only improves the sensitivity and reliability of the system, but also enhances redundancy and flexibility, and can better adapt to different application scenarios and technical requirements.

[0103] When the sensing resistor 1 is a nonlinear positive temperature coefficient sensing resistor.

[0104] Specifically, the fault detection module 3 is a detection circuit that can be used to detect the resistance between the output pins of the circuit board 2. When any one or more battery cells in the battery module thermally run away and reach the set temperature, the corresponding sensing resistor 1 resistance value instantly changes to a high resistance state. The fault detection module 3 detects that the resistance between the output pins of the circuit board 2 increases instantaneously, and outputs a shutdown signal to the control module 4 and the drive module 5.

[0105] The fault detection module 3 continuously monitors the resistance state between the output pins of the circuit board 2. The resistance state of the output pins of the circuit board 2 may change or may not change. The fault detection module 3 can output a corresponding shutdown signal according to the resistance state of the output pins of the circuit board 2 to ensure that any abnormal situation can be captured in time. If there is a problem with the fault detection module 3, it can be easily replaced or repaired, reducing maintenance costs and time.

[0106] The fault detection module 3 can output a shutdown signal to the drive module 5, directly disconnecting the power circuit through hardware, shortening the response time, enhancing the safety of the system, ensuring normal operation when a single channel fails, and improving the reliability of the system.

[0107] Specifically, the fault detection module 3 includes a first resistor R1, a second resistor R2, a third resistor R3 and an optocoupler U1. One end of the third resistor R3, the circuit board 2 and the pin a of the optocoupler U1 are connected in series in sequence. The other end of the third resistor R3 is connected to the power supply VCC1, the pin b of the optocoupler U1 is grounded, the pin c of the optocoupler U1 is connected to the power supply VCC2, the pin d of the optocoupler U1 is respectively connected to one end of the first resistor R1 and the second resistor R2, the other end of the first resistor R1 is respectively connected to the control module 4 and the drive module 5, and the other end of the second resistor R2 is grounded.

[0108] The optocoupler U1 provides electrical isolation between the input side and the output side, preventing high voltage or interference from being transmitted from one part to another, improving the safety and stability of the system. When the sensing resistor 1 detects temperature anomalies, the optocoupler U1 can respond quickly and protect the system in time, enhancing the circuit's anti-interference ability and ensuring stable operation even in harsh environments.

[0109] This setting effectively prevents direct electrical connection between the two sides through electrical isolation, reducing the risk of short circuit and electric shock. The optocoupler U1 is very sensitive to current changes and can quickly detect temperature anomalies to ensure that protective measures are taken in time.

[0110] Specifically, the specific working process of the fault detection module 3 is as follows: when the temperature of all battery cells is normal, the output resistance of the sensing resistor 1 is about 0 ohms, the input LED of the optocoupler U1 is lit, the output end of the optocoupler U1 is turned on, and the shutdown signal is high level; when any one or more battery cells are thermally runaway, the output resistance of the sensing resistor 1 is in a high resistance state, the current flowing through the input LED of the optocoupler U1 is almost 0mA, the output end of the optocoupler U1 is disconnected, and the shutdown signal is low level. The fault detection module 3 sends a shutdown signal to the drive module 5, and feeds back the shutdown signal state to the control module 4.

[0111] The fault detection module 3 continuously monitors the total resistance between the output pins of the sensing resistor 1 to ensure that any abnormal situation can be captured in time. Once the total resistance increases, the protection mechanism is immediately triggered and a shutdown signal is issued to prevent the thermal runaway from spreading further.

[0112] Fault detection module 3 uses hardware-level protection, such as the setting of optocoupler U1, to enhance the overall reliability of the system. At the same time, fault detection module 3 can be used as an independent module, which is convenient for expansion or replacement according to actual needs, improves the flexibility of the system, simplifies system design, and reduces the need for external components. If there is a problem with fault detection module 3, it can be easily replaced or repaired, reducing maintenance costs and time.

[0113] Through the above-mentioned specific workflow, the fault detection module 3 realizes accurate monitoring and rapid response to the thermal runaway temperature of the battery cell surface in the battery module, which not only improves the accuracy and reliability of the system, but also enhances safety and flexibility, and is suitable for various battery applications that require high reliability and high performance. In addition, the characteristics of hardware-level protection, intelligent control and simplified design also make the solution more practical and scalable.

[0114] Specifically, the control module 4 is an MCU, which is used to receive the shutdown signal sent by the fault detection module 3. When the shutdown signal is detected to be valid, the control signal is disabled. Only when it is detected that the shutdown signal is released and the battery cell temperature drops to the set recovery temperature, the control signal is enabled again to prevent the power module 6 from being frequently turned on and off due to temperature fluctuations.

[0115] The control module 4 continuously monitors the fault shutdown signal from the fault detection module 3. In the case where no effective fault shutdown signal is detected, the control module 4 maintains the enabled state of the control signal, allowing the power module 6 to operate normally.

[0116] When the control module 4 detects a valid shutdown signal, that is, the shutdown signal becomes low level, the control signal is immediately disabled, the drive signal of the power module 6 is cut off, and the system is ensured to enter a safe state. At the same time, the control module 4 records the fault information for subsequent analysis and maintenance.

[0117] Even if the shutdown signal is released, that is, the shutdown signal returns to a high level, the control module 4 will not immediately re-enable the control signal, but the control module 4 obtains the precise temperature of the battery cell from the battery cell temperature detection device. Only when the battery cell temperature drops to the set safety temperature threshold for a period of time T 安 After this time T 安 It usually takes from tens of milliseconds to several minutes for the control module 4 to re-enable the control signal and restore the normal operation of the power module 6 .

[0118] By setting a certain temperature hysteresis or delay mechanism, it is ensured that the control signal is re-enabled only when the temperature is truly stable and below the set threshold, ensuring that the system is truly restored to a safe state after troubleshooting, avoiding misoperation and frequent conduction and disconnection due to temperature fluctuations, extending the life of the battery module and related components, and improving the reliability and stability of the system.

[0119] Preferably, when the sensing resistor 1 detects that the surface temperature of the battery cell is 150°C, it is determined that the battery cell is in thermal runaway. At this time, the system triggers the protection mechanism. When the power supply is restored after the fault is eliminated, the recovery temperature is set to be no higher than 45°C.

[0120] When the sensing resistor 1 detects that the surface temperature of the battery cell reaches 150°C, it is identified as a thermal runaway state. This temperature point is usually the critical point before the battery cell may be irreversibly damaged or in a dangerous situation. Once it reaches 150°C, the system immediately triggers the protection mechanism, cuts off the power supply, and prevents the thermal runaway from spreading further. The 150°C setting can capture the state of the battery cell approaching thermal runaway in time, provide early warning, and quickly take protective measures to prevent the accident from expanding.

[0121] Before restoring power, other normal temperature detection systems are required to detect that the temperature of the battery cell is no higher than 45°C. This temperature point ensures that the battery cell has been fully cooled and returned to the safe operating range. By setting a lower recovery temperature threshold, secondary failures or safety hazards caused by incomplete temperature drop can be avoided.

[0122] This setting ensures that abnormalities can be detected sensitively without false alarms due to normal fluctuations by reasonably setting the two temperature thresholds of 150℃ and 45℃. It sets a higher thermal runaway threshold of 150℃ and a lower recovery threshold of 45℃ to prevent frequent conduction and disconnection due to temperature fluctuations, reduce wear on the system and components, and extend the service life of the system.

[0123] Specifically, the control module 4 may report the fault status and control other components to perform other protection actions.

[0124] The control module 4 records the occurrence time, temperature change and other information of each fault for subsequent analysis and improvement. Combined with the BMS battery management system, the fault information can be uploaded to the remote monitoring center to achieve remote management and maintenance.

[0125] Specifically, the driving module 5 is the driving circuit of the power module 6, which contains a logic gate processing circuit. Only when the shutdown signal output by the fault detection module 3 fails and the conduction control signal output by the control module 4 is valid, the driving module 5 will output a valid driving signal to turn on the power module 6.

[0126] Normal working status

[0127] The shutdown signal output by the fault detection module 3 is high level, indicating that the temperature of all battery cells is normal and the shutdown signal is invalid. The conduction control signal output by the control module 4 is high level, indicating that the system allows the power module 6 to be turned on and the conduction control signal is valid. If both conditions are met, the drive module 5 outputs a valid drive signal to turn on the power module 6 and the battery module works normally.

[0128] Fault Response

[0129] When any one or more cells experience thermal runaway, the shutdown signal output by the fault detection module 3 becomes low level, and the shutdown signal is effective. Since the shutdown signal is low level, the drive module 5 will not output a valid drive signal, the power module 6 is disconnected, and the power supply is cut off to prevent the spread of thermal runaway. At this time, the drive module 5 directly controls the power module 6 to disconnect, without waiting for the control signal of the control module 4, so even if the conduction control signal output by the control module is still high level, it does not affect the disconnection of the power module 6.

[0130] Restoring power

[0131] When the fault is eliminated, the battery cell temperature drops to a safe range, the shutdown signal output by the fault detection module 3 returns to a high level, and the shutdown signal becomes invalid. After the control module 4 confirms that the temperature has returned to normal, it re-outputs a valid conduction control signal. When the two conditions are met again, the drive module 5 outputs a valid drive signal, causing the power module 6 to turn on again and resume power supply.

[0132] The state truth table between the shutdown signal, control signal, drive signal, and power module state is as follows:

[0133] Table 1. Truth table of shutdown signal, control signal, drive signal, and power module status

[0134] Shutdown signal Control Signal Drive signal Power module status high high high Conductivity Low Low disconnect high Low Low disconnect Low Low Low disconnect

[0135] Through the logic gate processing circuit, it is ensured that only when the signals of the fault detection module 3 and the control module 4 meet the conditions at the same time, the effective drive signal will be output, which enhances the reliability and safety of the system. Even if one of the modules is abnormal, the other module can play a protective role to avoid the safety risks caused by misoperation. Once thermal runaway is detected, the drive module 5 immediately stops outputting the drive signal and quickly cuts off the current path of the power module 6 to prevent the thermal runaway from spreading further. The logic gate circuit has good anti-interference ability to avoid the influence of external electromagnetic interference or noise on the drive signal.

[0136] This setting achieves fast response through hardware logic circuits, shortens reaction time, provides hardware-level protection, and enhances system security. At the same time, combined with the temperature stability check function of control module 4, it ensures that the system will restart only after it is truly restored to a safe state to avoid secondary failures.

[0137] Specifically, the power module 6 is a power switch circuit, which turns on the power circuit when the received driving signal is valid, otherwise the power circuit is turned off.

[0138] When the drive module 5 outputs a valid high-level drive signal, the power switches inside the power module 6, such as MOSFET, IGBT, etc., are turned on. The current path of the battery module is established, allowing normal charging and discharging operations. When the drive module 5 stops outputting a valid low-level drive signal, the power switch inside the power module 6 is turned off. The current path of the battery module is cut off to prevent further spread of thermal runaway or other abnormal conditions. When the system confirms that the fault has been eliminated and the temperature has returned to normal, the drive module 5 re-outputs a valid drive signal. The power module 6 turns on the power circuit again and resumes normal charging and discharging operations.

[0139] The power module 6 accurately controls the on and off of the power circuit according to the state of the driving signal to ensure the stable operation of the system. It is only turned on when a valid driving signal is received to avoid unnecessary operations caused by external interference or false triggering. High-efficiency power switching devices such as MOSFET and IGBT are used to provide a low-impedance path in the on state to reduce energy loss. In the off state, the current path is completely isolated to avoid unnecessary energy consumption and improve overall energy efficiency.

[0140] The power switch can complete the on and off operation within microseconds, ensuring that the system can operate reliably under various conditions. Combined with the dual verification mechanism of the drive module 5 and the control module 4, the overall reliability of the system is improved. Different types of power switch devices can be selected according to actual needs, and the control logic can be flexibly adjusted. The design of the power module 6 is easy to integrate with other monitoring and control systems, which is convenient for subsequent expansion and upgrading.

[0141] This arrangement realizes accurate response to the drive signal and reliable control of the power loop by designing the power module 6 as a power switching circuit, thereby improving the accuracy and reliability of the system.

[0142] Another object of the present invention is to disclose a method for detecting and processing a thermal runaway fault of a battery cell in a battery module, when the sensing resistor 1 is a nonlinear positive temperature coefficient sensing resistor, comprising the following specific steps:

[0143] S1: The sensing resistor 1 detects the surface temperature of the corresponding battery cell in real time, and the fault detection module 3 detects the output resistance state of the circuit board 2;

[0144] S2: When the fault detection module 3 detects that the output resistance state of the circuit board 2 is in a high resistance state, step S3 is executed; when the fault detection module 3 detects that the output resistance state of the circuit board 2 is in a low resistance state, step S4 is executed;

[0145] S3: The fault detection module 3 outputs a low-level shutdown signal to the control module 4 and the drive module 5, and the drive module 5 outputs a low-level drive signal to control the power module 6 to disconnect. At the same time, the control module 4 records the time and information of the thermal runaway event and issues an alarm, and then executes step S11;

[0146] S4: the fault detection module 3 outputs a high-level shutdown signal to the control module 4, and the control module 4 determines whether there is a thermal runaway record in the previous period T. If yes, the control module 4 executes step S5; if no, the control module 4 executes step S8;

[0147] S5: Obtain the temperature of the battery cell, and the control module 4 determines whether the temperature of the battery cell is greater than or equal to the set recovery temperature. If yes, execute step S6; if no, execute step S8;

[0148] S6: The control module 4 outputs a low-level control signal and issues an alarm that the recovery temperature has not been reached;

[0149] S7: After receiving the low-level control signal, the driving module 5 outputs a low-level driving signal to control the power module 6 to be disconnected, and then executes step S10;

[0150] S8: The control module 4 outputs a high-level control signal to the driving module 5;

[0151] S9: After receiving the high-level control signal, the driving module 5 outputs a high-level driving signal to control the power module 6 to be turned on, and step S1 is executed;

[0152] S10: After time t1 has passed or the temperature of the battery cell is continuously detected, step S5 is executed;

[0153] S11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step S1.

[0154] When thermal runaway of the battery cell occurs at T1, the total series resistance of all the sensing resistors 1 is in a high-resistance state, the output of the circuit board 2 is in a high-resistance state, and the shutdown signal output by the fault detection module 3 is at a low level. At this time, no matter whether the control signal output by the control module 4 is at a high level or a low level, the drive signal output by the drive module 5 is at a low level, and the power module 6 is disconnected.

[0155] During the thermal runaway period T2 of the battery cell, the total series resistance of all the sensing resistors 1 is in a high-resistance state, the output of the circuit board 2 is in a high-resistance state, the shutdown signal output by the fault detection module 3 is at a low level, and the control module 4 adjusts the output control signal to a low level after detecting the thermal runaway, the drive signal output by the drive module 5 is at a low level, and the power module 6 is disconnected.

[0156] During the battery cell thermal runaway recovery period T3, the output resistance of the circuit board 2 is in a low resistance state, the shutdown signal output by the fault detection module 3 is at a high level, the control module 4 detects that the battery cell temperature has not recovered to the set temperature, the output control signal is at a low level, the drive signal output by the drive module 5 is at a low level, and the power module 6 is disconnected.

[0157] During the battery cell thermal runaway recovery period T4, the total series resistance of all the sensing resistors 1 is in a low resistance state, the output resistance of the circuit board 2 is in a low resistance state, the shutdown signal output by the fault detection module 3 is high level, the control module 4 detects that the battery cell temperature has returned to the set temperature, the output control signal is high level, the drive signal output by the drive module 5 is high level, and the power module 6 is turned on.

[0158] Once thermal runaway is detected, the power supply is immediately cut off to prevent the accident from expanding. Through temperature stability checks, ensure that the system is restarted only after it has truly recovered to a safe state to avoid secondary failures. The combination of hardware-level protection such as optocoupler U1 and software-level control MCU improves the overall reliability of the system. At the same time, the logic gate processing circuit has good anti-interference ability to avoid the influence of external electromagnetic interference or noise on the drive signal. Different temperature thresholds and hysteresis can also be selected according to actual needs. By setting reasonable temperature thresholds and hysteresis, frequent conduction and disconnection caused by temperature fluctuations can be prevented, wear on the system and components can be reduced, and system performance can be optimized. At the same time, combined with the BMS battery management system, temperature information can be uploaded to the remote monitoring center to achieve remote management and maintenance. After confirming that the battery cell temperature has dropped to a safe range, the system can automatically restore power supply without manual intervention, which improves the user experience. The system also has the function of recording detailed fault information for subsequent analysis and improvement.

[0159] This setting realizes a double verification mechanism by combining the hardware-level protection of the fault detection module 3 and the software-level control of the control module 4, thereby enhancing the reliability and safety of the system. It introduces a temperature stability check function to ensure that the power module 6 will not be turned on again until the battery cell temperature is truly restored to a safe range, thereby avoiding frequent switching due to temperature fluctuations, immediately cutting off the power supply at the moment of thermal runaway, and restarting only after confirming that the fault has been eliminated and the temperature has returned to normal, reflecting the innovative design of rapid response and intelligent recovery.

[0160] Specifically, in steps S5 and S10, the temperature of the battery cell is obtained, and the control module 4 obtains it from another temperature detection device, which may be the specific temperature of the battery cell transmitted by a conventional battery cell temperature detection circuit. The sensing resistor 1 is only used for temperature detection to determine whether thermal runaway occurs in the battery cell.

[0161] Specifically, within a time T, the temperature of the battery cells in the battery module that has thermal runaway and the battery cells in the surrounding battery modules can be reduced to a temperature lower than a preset recovery temperature. The time T may be 2 hours, 6 hours or 24 hours.

[0162] Within the time T from the occurrence of the thermal runaway event, the surface temperature of the battery cell reaches above the set recovery temperature again, and the battery module is considered to be in an unsafe state. This time can be set according to factors such as battery type and capacity, environmental conditions, severity of thermal runaway, physical structure and packaging, and initial temperature peak to ensure the safety of the system. During this time T, although the sensing resistor 1 is in a low resistance state, the control module 4 outputs a low-level control signal, and the drive module 5 outputs a low-level drive signal after receiving the low-level control signal, and the control power module 6 is disconnected.

[0163] Specifically, in step S10, time t1 is less than time T.

[0164] Specifically, when the resistance of the sensing resistor 1 is approximately 0 ohm, that is, between 1 mΩ and 1Ω, the specific steps are as follows:

[0165] When the temperatures of all battery cells are normal, the total series resistance of all sensing resistors 1 is approximately equal to 0 ohms, the output resistance of the circuit board 2 is approximately equal to 0 ohms, the shutdown signal output by the fault detection module 3 is high level, the control signal output by the control module 4 is high level, the drive signal output by the drive module 5 is high level, and the power module 6 is turned on.

[0166] At the moment T1 when thermal runaway of the battery cell occurs, the total series resistance of all the sensing resistors 1 is in a high-resistance state, the output of the circuit board 2 is in a high-resistance state, and the shutdown signal output by the fault detection module 3 is at a low level. At this time, no matter whether the control signal output by the control module 4 is at a high level or a low level, the drive signal output by the drive module 5 is at a low level, and the power module 6 is disconnected.

[0167] During the thermal runaway period T2 of the battery cell, the total series resistance of all the sensing resistors 1 is in a high-resistance state, the output of the circuit board 2 is in a high-resistance state, the shutdown signal output by the fault detection module 3 is at a low level, and the control module 4 adjusts the output control signal to a low level after detecting the thermal runaway, the drive signal output by the drive module 5 is at a low level, and the power module 6 is disconnected.

[0168] During the battery cell thermal runaway recovery period T3, the total series resistance of all the sensing resistors 1 is approximately equal to 0 ohms, the output resistance of the circuit board 2 is approximately equal to 0 ohms, the shutdown signal output by the fault detection module 3 is high, the control module 4 detects that the battery cell temperature has not recovered to the set temperature, the output control signal is low, the drive signal output by the drive module 5 is low, and the power module 6 is disconnected.

[0169] During the battery cell thermal runaway recovery period T4, the total series resistance of all the sensing resistors 1 is approximately equal to 0 ohm, the output resistance of the circuit board 2 is approximately equal to 0 ohm, the shutdown signal output by the fault detection module 3 is high, the control module 4 detects that the battery cell temperature has returned to the set temperature, the output control signal is high, the drive signal output by the drive module 5 is high, and the power module 6 is turned on.

[0170] The design of the sensing resistor 1 having a resistance value of approximately 0 ohm can further reduce the energy consumption of the detection circuit and reduce the power supply cost of the detection circuit inside the system.

[0171] When the sensing resistor 1 is a nonlinear negative temperature coefficient sensing resistor, the resistance state and signal state during the system operation process are opposite to those of the nonlinear positive temperature coefficient sensing resistor.

[0172] For example, a method for quickly detecting and processing a battery cell thermal runaway fault in a battery module, based on any of the above-mentioned systems for detecting and processing a battery cell thermal runaway fault, specifically includes the following steps:

[0173] ST1: The sensing resistor 1 detects the surface temperature of the corresponding battery cell in real time, and the fault detection module 3 detects the output resistance state of the circuit board 2;

[0174] ST2: When the fault detection module 3 detects that the output resistance state of the circuit board 2 is in a low resistance state, step S3 is executed; when the fault detection module 3 detects that the output resistance state of the circuit board 2 is in a high resistance state, step ST4 is executed;

[0175] ST3: The fault detection module 3 outputs a high-level shutdown signal to the control module 4 and the drive module 5, and the drive module 5 outputs a high-level drive signal to control the power module 6 to disconnect. At the same time, the control module 4 records the time and information of the thermal runaway event and issues an alarm, and executes step ST11;

[0176] ST4: The fault detection module 3 outputs a low-level shutdown signal to the control module 4, and the control module 4 determines whether there is a thermal runaway record within the previous period T. If yes, it executes step ST5; if no, it executes step ST8;

[0177] ST5: Obtain the temperature of the battery cell. The control module 4 determines whether the temperature of the battery cell is greater than or equal to the set recovery temperature. If yes, execute step ST6; if no, execute step ST8;

[0178] ST6: The control module 4 outputs a high-level control signal and issues an alarm that the recovery temperature has not been reached;

[0179] ST7: After receiving the high-level control signal, the driving module 5 outputs a low-level driving signal to control the power module 6 to be disconnected, and then executes step ST10;

[0180] ST8: The control module 4 outputs a low-level control signal to the driving module 5;

[0181] ST9: After receiving the high-level control signal, the driving module 5 outputs a high-level driving signal to control the power module 6 to be turned on, and step ST1 is executed;

[0182] ST10: After time t1 has passed or the temperature of the battery cell is continuously detected, step ST5 is executed;

[0183] ST11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step ST1.

[0184] Specifically, in steps ST5 and ST10, the temperature of the battery cell is obtained, and the control module 4 obtains it from another temperature detection device, which can be the specific temperature of the battery cell transmitted by a conventional battery cell temperature detection circuit. The sensing resistor 1 is only used for temperature detection of whether thermal runaway occurs in the battery cell.

[0185] Specifically, in step ST10 , time t1 is less than time T.

[0186] Specifically, when multiple battery modules are applied to the field of new energy vehicles or other fields, the multiple battery modules can be connected through a flexible circuit board. The specific connection method can be series connection, parallel connection or series-parallel connection, and finally connected to two output pins for the fault detection module 3 to detect the resistance state.

[0187] Specifically, a plurality of flexible circuit boards may be respectively connected to the fault detection modules 3 .

[0188] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for detecting and processing thermal runaway failures of battery modules, characterized in that: include: A plurality of sensing resistors (1), wherein the resistance value of the sensing resistor (1) changes with temperature, and the sensing resistor (1) is used to detect changes in the surface temperature of a corresponding battery cell; The circuit board (2) is used to fix the sensing resistor (1) and connect all the sensing resistors (1); The fault detection module (3) is used to detect the resistance state of the sensing resistor (1) and output a shutdown signal at the same time; The control module (4) is used to receive the shutdown signal output by the fault detection module (3), and send a control signal to the drive module (5); The driving module (5) is used to receive the shutdown signal output by the fault detection module (3) and the control signal output by the control module (4), and output the driving signal after processing, or the driving module (5) directly outputs the driving signal according to the shutdown signal to control the power module (6); The power module (6) is used to receive the drive signal output by the drive module (5) and execute the switching on and off of the power circuit.

2. The system for detecting and processing thermal runaway failure of a battery module according to claim 1, characterized in that: The sensing resistor (1) is arranged on one surface or multiple surfaces of each battery cell.

3. The system for detecting and processing thermal runaway failure of a battery module according to claim 1, characterized in that: The sensing resistor (1) is a nonlinear positive temperature coefficient sensing resistor or a nonlinear negative temperature coefficient sensing resistor.

4. The system for detecting and processing thermal runaway failure of a battery module according to claim 1, characterized in that: The circuit board (2) is a flexible circuit board, and a terminal of the circuit board (2) is provided with two output pins for detecting the resistance states of all the sensing resistors (1) after they are connected.

5. The system for detecting and processing thermal runaway failure of a battery module according to claim 4, characterized in that: The sensing resistors (1) are welded on the circuit board (2), and all the sensing resistors (1) are connected in series, in parallel, or in series-parallel, and are connected to two output pins of a terminal of the circuit board (2).

6. The system for detecting and processing thermal runaway failure of a battery module according to claim 4, characterized in that: The fault detection module (3) is a detection circuit used to detect the resistance state between the output pins of the circuit board (2), and output a shutdown signal to the control module (4) and the drive module (5) according to the resistance state detected between the output pins of the circuit board (2).

7. The system for detecting and processing thermal runaway failure of a battery module according to claim 1, characterized in that: The fault detection module (3) comprises a first resistor R1, a second resistor R2, a third resistor R3 and an optocoupler U1; one end of the third resistor R3, the circuit board (2) and a pin a of the optocoupler U1 are connected in series in sequence; the other end of the third resistor R3 is connected to a power supply VCC1; a pin b of the optocoupler U1 is grounded; a pin c of the optocoupler U1 is connected to a power supply VCC2; a pin d of the optocoupler U1 is respectively connected to one end of the first resistor R1 and one end of the second resistor R2; the other end of the first resistor R1 is respectively connected to the control module (4) and the drive module (5); and the other end of the second resistor R2 is grounded.

8. The system for detecting and processing thermal runaway failure of a battery module according to claim 1, characterized in that: The power module (6) is a power switch circuit, which switches on the power circuit when the received drive signal is valid, otherwise the power circuit is disconnected.

9. A method for quickly detecting and processing thermal runaway failures of battery modules, characterized in that: Based on the system for detecting and processing thermal runaway failure of a battery module according to any one of claims 1 to 8, when the sensing resistor (1) is a nonlinear positive temperature coefficient sensing resistor, the system specifically comprises the following steps: S1: the sensing resistor (1) detects the surface temperature of the corresponding battery cell in real time, and the fault detection module (3) detects the output resistance state of the circuit board (2); S2: when the fault detection module (3) detects that the output resistance state of the circuit board (2) is in a high resistance state, executing step S3; when the fault detection module (3) detects that the output resistance state of the circuit board (2) is in a low resistance state, executing step S4; S3: the fault detection module (3) outputs a low-level shutdown signal to the control module (4) and the drive module (5), the drive module (5) outputs a low-level drive signal to control the power module (6) to disconnect, and at the same time the control module (4) records the time and information of the thermal runaway event and issues an alarm, and then executes step S11; S4: the fault detection module (3) outputs a high-level shutdown signal to the control module (4), and the control module (4) determines whether there is a thermal runaway record within the previous period T. If yes, step S5 is executed; if no, step S8 is executed; S5: obtaining the temperature of the battery cell, the control module (4) judging whether the temperature of the battery cell is greater than or equal to a set recovery temperature, if yes, executing step S6, if no, executing step S8; S6: the control module (4) outputs a low-level control signal and simultaneously issues an alarm indicating that the recovery temperature has not been reached; S7: after receiving the low-level control signal, the driving module (5) outputs a low-level driving signal to control the power module (6) to be disconnected, and step S10 is executed; S8: the control module (4) outputs a high-level control signal to the drive module (5); S9: after receiving the high-level control signal, the driving module (5) outputs a high-level driving signal to control the power module (6) to be turned on, and step S1 is executed; S10: After time t1 has passed or the temperature of the battery cell is continuously detected, step S5 is executed; S11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step S1.

10. A method for quickly detecting and processing thermal runaway failures of battery cells in a battery module, characterized in that: Based on the system for detecting and processing thermal runaway failure of a battery module according to any one of claims 1 to 8, when the sensing resistor (1) is a nonlinear negative temperature coefficient sensing resistor, the system specifically comprises the following steps: ST1: the sensing resistor (1) detects the surface temperature of the corresponding battery cell in real time, and the fault detection module (3) detects the output resistance state of the circuit board (2); ST2: when the fault detection module (3) detects that the output resistance state of the circuit board (2) is in a low resistance state, executing step ST3; when the fault detection module (3) detects that the output resistance state of the circuit board (2) is in a high resistance state, executing step ST4; ST3: the fault detection module (3) outputs a high-level shutdown signal to the control module (4) and the drive module (5), the drive module (5) outputs a high-level drive signal to control the power module (6) to be disconnected, and at the same time the control module (4) records the time and information of the occurrence of the thermal runaway event and issues an alarm, and then executes step ST11; ST4: the fault detection module (3) outputs a low-level shutdown signal to the control module (4), and the control module (4) determines whether there is a thermal runaway record within the previous period T. If yes, the control module (4) executes step ST5; if no, the control module (4) executes step ST8; ST5: obtaining the temperature of the battery cell, the control module (4) determining whether the temperature of the battery cell is greater than or equal to a set recovery temperature, if yes, executing step ST6, if no, executing step ST8; ST6: the control module (4) outputs a high-level control signal and simultaneously issues an alarm indicating that the recovery temperature has not been reached; ST7: after receiving the high-level control signal, the driving module (5) outputs a low-level driving signal to control the power module (6) to be disconnected, and step ST10 is executed; ST8: the control module (4) outputs a low-level control signal to the driving module (5); ST9: after receiving the high-level control signal, the driving module (5) outputs a high-level driving signal to control the power module (6) to be turned on, and step ST1 is executed; ST10: After time t1 has passed or the temperature of the battery cell is continuously detected, step ST5 is executed; ST11: After receiving the battery cell thermal runaway alarm, perform a fault elimination operation. After the fault is eliminated, execute step ST1.

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