Method for detecting thermal runaway of vehicle

Abstract

The invention discloses a thermal runaway detection method for a vehicle. The method comprises the following steps: acquiring a first voltage value and a first temperature value after the vehicle is powered off; whether the first voltage value is within a first preset range or not and / or whether the first temperature value is within a second preset range or not is judged; if the first voltage value is not within the first preset range and / or the first temperature value is not within the second preset range, the BMS is awakened and kept for first preset time; and within the first preset time, characteristic parameters of the power battery are obtained, whether the characteristic parameters meet the thermal runaway triggering condition of the vehicle or not is judged, and whether a thermal runaway event occurs or not is determined according to the judgment result. According to the thermal runaway detection method of the vehicle, the judgment on the sampling abnormity of the AFE chip or the failure mode of the AFE chip is added, the thermal runaway risk detection after reverse wake-up is optimized, and the situation that the thermal runaway of the vehicle cannot be accurately diagnosed when the AFE chip fails or is abnormal is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and more particularly to a method for detecting thermal runaway of a vehicle. Background Art

[0002] In related technologies, the method for detecting thermal runaway of a vehicle mainly wakes up the system regularly or when the voltage and temperature reach a preset wake-up threshold, or judges the thermal runaway under preset conditions after the BMS is powered on, without considering the influence of the state of the AFE chip on the accuracy of thermal runaway diagnosis. If the AFE chip is abnormal or fails, it may lead to incorrect thermal runaway diagnosis. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, an object of the present invention is to propose a method for detecting thermal runaway of a vehicle to solve the problem of incorrect thermal runaway diagnosis of the vehicle caused by an abnormal or failed AFE chip.

[0004] According to an embodiment of the present invention, a method for detecting thermal runaway of a vehicle includes: obtaining a first voltage value and a first temperature value after the vehicle is powered off; judging whether the first voltage value is within a first preset range, and / or whether the first temperature value is within a second preset range; if the first voltage value is not within the first preset range, and / or the first temperature value is not within the second preset range, wake up the BMS and maintain for a first preset time; within the first preset time, obtain characteristic parameters of the power battery, and judge whether the characteristic parameters meet the thermal runaway trigger condition of the vehicle, and determine whether a thermal runaway event occurs according to the judgment result.

[0005] According to the method for detecting thermal runaway of a vehicle according to an embodiment of the present invention, the judgment of abnormal sampling of the AFE chip or the failure mode of the AFE chip is added, and the detection of thermal runaway risk after reverse wake-up is optimized, avoiding inaccurate diagnosis of thermal runaway of the vehicle when the AFE chip fails or is abnormal.

[0006] According to some embodiments of the present invention, if the characteristic parameters meet the thermal runaway trigger condition of the vehicle, it is determined that a thermal runaway event occurs in the vehicle, and the message sending switch is turned on and the thermal runaway event is reported.

[0007] According to some embodiments of the present invention, if the characteristic parameters do not meet the thermal runaway trigger condition of the vehicle, it is determined that no thermal runaway event occurs in the vehicle, and the whole vehicle is powered off and put into sleep after the first preset time.

[0008] According to some embodiments of the present invention, if the first voltage value is within a first preset range, it is determined whether the current voltage value reaches a first wake-up threshold and remains for a second preset time; and / or, if the first temperature value is within a second preset range, it is determined whether the current temperature value reaches a second wake-up threshold and remains for a second preset time.

[0009] According to some embodiments of the present invention, if the current voltage value reaches the first wake-up threshold and remains for the second preset time, and / or, the current temperature value reaches the second wake-up threshold and remains for the second preset time, then the BMS is woken up and the message sending switch is turned on.

[0010] According to some embodiments of the present invention, characteristic parameters of the power battery are obtained, and it is determined whether the characteristic parameters meet the thermal runaway trigger conditions of the vehicle.

[0011] According to some embodiments of the present invention, if the characteristic parameters meet the thermal runaway trigger conditions of the vehicle, it is determined that a thermal runaway event has occurred in the vehicle, and the thermal runaway event is reported; if the characteristic parameters do not meet the thermal runaway trigger conditions of the vehicle, the vehicle is powered off and put into sleep after a third preset time.

[0012] According to some embodiments of the present invention, if the current voltage value does not reach the first wake-up threshold and remains for the second preset time, and / or, the current temperature value does not reach the second wake-up threshold and remains for the second preset time, the AFE chip goes into sleep.

[0013] According to some embodiments of the present invention, the characteristic parameters include: within a fourth preset time, the temperature rise value of the power battery is greater than a first preset value; within a fifth preset time, the voltage drop value of the power battery is greater than a second preset value; the temperature difference of the power battery is greater than a third preset value; the temperature of the power battery is greater than a fourth preset value; the voltage of the power battery is less than a fifth preset value; a voltage sampling fault of the power battery; a temperature sampling fault of the power battery; an insulation fault inside the power battery pack; a communication loss fault of the AFE chip.

[0014] According to some embodiments of the present invention, the thermal runaway trigger conditions include at least two of the characteristic parameters being triggered.

[0015] According to the thermal runaway detection method of the vehicle of the present invention, by judging the rationality of the first voltage value and the first temperature value obtained after the vehicle is powered off, the judgment of the sampling abnormality or the failure mode of the AFE chip is increased, the thermal runaway risk detection after reverse wake-up is optimized, and the situation that the AFE chip cannot accurately diagnose the thermal runaway of the vehicle due to failure or abnormality is avoided.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be learned by practice of the present invention. Description of the Drawings

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, in which:

[0018] Figure 1 is a flowchart of a part of a method for detecting thermal runaway of a vehicle according to some embodiments of the present invention;

[0019] Figure 2 is a flowchart of another part of a method for detecting thermal runaway of a vehicle according to some embodiments of the present invention. Detailed Description of the Embodiments

[0020] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0022] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "mounted", "connected" and "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] The following refers to Figure 1 - Figure 2Describe a method for detecting thermal runaway of a vehicle according to an embodiment of the present invention.

[0024] For a method for detecting thermal runaway of a vehicle according to an embodiment of the present invention, the thermal runaway detection method includes:

[0025] S1: Obtain a first voltage value and a first temperature value after the vehicle is powered off.

[0026] The battery management system (BMS) has a battery sampling chip (AFE chip) and a control unit (MCU). The AFE chip is responsible for monitoring the voltage, temperature, and other important parameters of each individual battery in the power battery, converting this information into digital signals, and sending them to the MCU. The MCU uses these digital signals to monitor the state of the power battery and formulate and execute corresponding control strategies.

[0027] After the vehicle is powered off, the AFE chip will obtain the first voltage value and the first temperature value after the vehicle is powered off in real time, convert them into digital signals, and send them to the MCU.

[0028] S2: Determine whether the first voltage value is within a first preset range, and / or determine whether the first temperature value is within a second preset range.

[0029] The MCU determines whether the first voltage value and / or the first temperature value is reasonable to determine whether the AFE chip has abnormal sampling or failure.

[0030] S3: If the first voltage value is not within the first preset range, and / or the first temperature value is not within the second preset range, then wake up the BMS and maintain it for a first preset time.

[0031] The thermal runaway detection method further includes: closing the message sending switch when waking up the BMS.

[0032] Specifically, it is to close the sending switch of the network management message. Only waking up the BMS without sending out the network management message can prevent other vehicle controllers from being woken up, resulting in an increase in the power consumption of the 12V battery and power failure.

[0033] The first voltage value not being within the first preset range may be due to an abnormality in the AEF chip itself or a thermal runaway problem in the power battery. At this time, it is necessary to wake up the BMS and maintain it for the first preset time. However, only locally wake up the BMS and close the network management message to prevent other vehicle controllers from being woken up and causing the battery to lose power. After waiting for the first preset time, if it is determined that the vehicle has not had a thermal runaway event, then power off and put the BMS into sleep mode. For example, the first preset range is from 10mv to 4900mv, and the specific value can be calibrated; if the first voltage value is less than 10mv or greater than 4900mv, the first voltage value is not within the first preset range.

[0034] The first temperature value is not within the second preset range. This may be due to an abnormality in the AEF chip itself or a thermal runaway problem in the power battery. At this time, the BMS needs to be awakened and maintained for the first preset time. However, only the BMS is locally awakened, and the network management message is turned off to avoid draining the battery due to awakening other vehicle controllers. After waiting for the first preset time, if it is determined that no thermal runaway event has occurred in the vehicle, the BMS is then powered off and put into sleep mode. For example, the second preset range is from -40°C to 150°C, and the specific values can be calibrated; if the first temperature value is less than -40°C or greater than 150°C, then the first temperature value is not within the second preset range.

[0035] The first voltage value is not within the first preset range, and / or the first temperature value is not within the second preset range, indicating that the first voltage value and / or the first temperature value is abnormal. It may be due to abnormal voltage of the power battery, abnormal voltage sampling line, or abnormal temperature of the power battery, abnormal temperature sampling line. It may also be due to abnormal power supply of the AFE chip or the AFE chip being in a failure mode. At this time, the BMS needs to be locally awakened, and it is necessary to determine whether the AFE chip has failed or whether a thermal runaway event has occurred in the power battery.

[0036] S4: Within the first preset time, obtain the characteristic parameters of the power battery, and determine whether the characteristic parameters meet the thermal runaway trigger conditions of the vehicle, and determine whether a thermal runaway event has occurred according to the judgment result.

[0037] In the prior art, the thermal runaway detection method of the vehicle mainly wakes up the system regularly or when the voltage and temperature reach the preset wake-up threshold, or judges the preset conditions for the thermal runaway of the power battery after the BMS is powered on. After the BMS is powered on and inspects the battery system, it will increase the risk of draining the power battery. In this application, the vehicle is powered off, and the state of the power battery is judged by using the first voltage value and the first temperature value obtained by the AFE chip. However, the AFE chip itself may be abnormal. For example, the power supply of the AFE chip is abnormal, or the voltage acquisition line or the temperature acquisition line is open or short-circuited, resulting in incorrect first voltage value and first temperature value obtained, and thus unable to accurately judge whether a thermal runaway event has occurred in the power battery. Therefore, this application adds the judgment of the AFE chip state, thus avoiding the inaccurate diagnosis of the vehicle's thermal runaway when the AFE chip fails or is abnormal.

[0038] In this application, in S1, the first voltage value and the first temperature value after the vehicle is powered off are obtained; in S2, the first voltage value and the first temperature value are judged; in S3, if the first voltage value and / or the first temperature value is abnormal, the BMS needs to be locally woken up, and the BMS can perform necessary monitoring and protection functions; in S4, by obtaining the characteristic parameters of the power battery and comparing the characteristic parameters, according to the comparison result, it is determined whether a thermal runaway event occurs in the vehicle; if the vehicle does not have a thermal runaway event, but the obtained first voltage value and / or first temperature value is abnormal, it may be that the AFE chip is abnormal, and the AFE chip needs to be checked.

[0039] After locally waking up the BMS, obtain the characteristic parameters of the power battery within the first preset time. According to the existing thermal runaway trigger conditions, judge whether a thermal runaway event occurs in the power battery by the obtained characteristic parameters of the power battery. If a thermal runaway event occurs in the power battery, report the thermal runaway event; if a thermal runaway event does not occur in the power battery, and the first voltage value and / or first temperature value obtained by the AFE chip is abnormal, it may be that the power supply of the AFE chip is abnormal or fails, or it may be that the voltage acquisition line or temperature acquisition line of the AFE chip is disconnected or short-circuited, resulting in the abnormal first voltage value and / or first temperature value obtained by the AFE chip.

[0040] The thermal runaway trigger conditions of the vehicle include the following conditions:

[0041] Within the fourth preset time, the temperature rise value of the power battery is greater than the first preset value. Within a fixed time, the temperature rise value of the power battery is too large, which may be due to excessive heat generated inside the power battery. For example, the fourth preset time is 5s, and the first preset value is 2°, that is, the temperature rise is greater than 2° within 5s.

[0042] Within the fifth preset time, the voltage drop value of the power battery is greater than the second preset value. Within a fixed time, the voltage drop value of the power battery is too large, which may be due to power battery aging, poor contact, etc. For example, the fifth preset time is 10s, and the second preset value is 25%, that is, the monomer voltage drop value is greater than 25% within 10s.

[0043] The temperature difference of the power battery is greater than the third preset value. The temperature of some battery packs of the power battery is too high, and the temperature of other battery packs is too low, resulting in a large temperature difference of the power battery and uneven temperature inside the power battery, which may cause the battery to undergo thermal runaway. For example, the third preset value is 20°, that is, the temperature difference of the power battery is greater than 20°.

[0044] The temperature of the power battery is greater than the fourth preset value. The temperature of the power battery is too high, which may be due to poor heat dissipation of the power battery or excessive heat generated by the power battery, both of which may cause thermal runaway of the power battery. For example, the fourth preset value is 60°, that is, the temperature of the power battery is greater than 60°.

[0045] The voltage of the power battery is less than the fifth preset value. The voltage of the power battery is less than the rated value, resulting in the power battery being unable to work properly or its performance degrading. For example, the fifth preset value is 2V, that is, the voltage of the power battery is less than 2V.

[0046] Voltage sampling failure of the power battery; temperature sampling failure of the power battery; insulation failure inside the power battery pack; communication loss failure of the AFE chip. All of the above problems will trigger thermal runaway of the power battery.

[0047] The thermal runaway trigger conditions include at least two characteristic parameters being triggered. When two or more characteristic parameters are triggered, it proves that the vehicle has experienced thermal runaway.

[0048] By judging the obtained first voltage value and / or first temperature value, and judging the characteristic parameters of the power battery, it is used to improve the accuracy of thermal runaway diagnosis when the vehicle is in the sleep state after the AFE chip fails.

[0049] According to the thermal runaway detection method of the vehicle of the present invention, the judgment of abnormal sampling of the AFE chip or the failure mode of the AFE chip is added, and the thermal runaway risk detection after reverse wake-up is optimized.

[0050] In a specific example, after obtaining the first voltage value and the first temperature value after the vehicle is powered off, it is also necessary to perform self-diagnosis on the AFE chip. The status code of the valid type of the sampling point of the AFE chip can be represented by natural numbers between 0 and 6. When the status code is 0 or 1, the data collected by the AFE chip is valid; when the status code is 2 or 3, the data collected by the AFE chip is untrustworthy or inaccurate; when the status code is 4 or 5, the data collected by the AFE chip is out of range, which may be too high or too low; when the status code is 6, there is a problem with the data collected by the AFE chip.

[0051] If the first voltage value is not within the first preset range, and / or the first temperature value is not within the second preset range, perform self-check on the AFE chip. If the AFE chip has the following abnormal wake-up situations:

[0052] 1. The status of the self-check sampling voltage point of the AFE chip is of type 5, and the AFE chip self-diagnoses a disconnection fault or the voltage of a single cell is 0V;

[0053] 2. The valid type of the AFE chip self-test sampling temperature point status is 4 or 5, and the analog-to-digital converter sampling of the measured temperature is greater than 2950mv or less than 50mv. The specific value can be calibrated;

[0054] 3. AFE chip power supply failure: The sampling voltage of a certain AFE chip does not meet the power supply voltage threshold, causing a single AFE sampling voltage failure or temperature failure;

[0055] 4. All AFE monomer voltages or temperatures fail: All monomer voltages or temperatures are invalid;

[0056] 5. Temperature sampling failure: valid type is 3, indicating daisy chain communication failure;

[0057] 6. Voltage sampling failure: The valid type is 3, indicating a daisy chain communication failure.

[0058] When any of the above problems occur in the AFE chip, the AFE chip abnormal wake-up conditions are met, and the AFE chip is considered abnormal or failed. At this time, the BMS is locally awakened and maintained for the first preset time, but the network management message is turned off to avoid waking up other vehicle controllers and causing battery power feeding.

[0059] According to some embodiments of the present invention, referring to Figure 1 , S41: If the characteristic parameters meet the thermal runaway triggering conditions of the vehicle, it is determined that a thermal runaway event occurs in the vehicle, the message sending switch is turned on and the thermal runaway event is reported.

[0060] The thermal runaway detection method also includes: the BMS remains awake, controls the vehicle to power off and sleep, and safely handles thermal runaway events. The BMS can continuously collect parameters of the power battery, monitor the status of the power battery at all times, and safely handle thermal runaway events to prevent the thermal runaway events of the power battery from continuing to spread or spread.

[0061] When a thermal runaway event occurs in a power battery, the message sending switch is turned on and the thermal runaway event is reported. The BMS can then handle the thermal runaway safely, including but not limited to: cutting off the circuit connection between the power battery and the load; using a special automatic fire extinguishing system to extinguish the power battery in the early stages of thermal runaway, and controlling the fire in the early stages; and formulating detailed emergency plans for staff, including emergency evacuation routes and assembly points, to ensure safe evacuation of dangerous areas in the shortest possible time.

[0062] According to some embodiments of the present invention, referring to Figure 1, S42: If the characteristic parameters do not meet the thermal runaway trigger conditions of the vehicle, it is determined that the vehicle has not experienced a thermal runaway event, and the vehicle is powered off and put into sleep after a first preset time; after comparing the characteristic parameters, if it is found that the characteristic parameters do not meet the thermal runaway trigger conditions of the vehicle, it proves that the vehicle has not experienced a thermal runaway event, and only the abnormal first voltage value and / or first temperature value are obtained. It may be that the AFE chip is abnormal, or the voltage acquisition line or temperature acquisition line of the AFE chip is disconnected or short-circuited, and the AFE chip needs to be checked.

[0063] According to some embodiments of the present invention, refer to Figure 2 , S5: If the first voltage value is within a first preset range, it is judged whether the current voltage value reaches a first wake-up threshold and remains for a second preset time; and / or, if the first temperature value is within a second preset range, it is judged whether the current temperature value reaches a second wake-up threshold and remains for a second preset time.

[0064] In S2, there is another situation for the judgment of the first voltage value and the first temperature value. The first voltage value is within the first preset range, and / or the first temperature value is within the second preset range. The first voltage value and / or the first temperature value after the vehicle is powered off are within a reasonable range. At this time, it is also necessary to judge the state of the AFE chip. By obtaining multiple voltage values within a second preset time and judging whether all the voltage values obtained within the second preset time reach the first wake-up threshold, and / or, within the second preset time, obtaining multiple temperature values and judging whether all the temperature values obtained within the second preset time reach the second wake-up threshold, to diagnose the state of the AFE chip again.

[0065] The first wake-up threshold is a parameter limit preset in the BMS. Judging whether the current voltage value reaches the first wake-up threshold is to judge whether the current voltage value reaches the preset parameter limit; the second wake-up threshold is a parameter limit preset in the BMS. Judging whether the current temperature value reaches the second wake-up threshold is to judge whether the current temperature value reaches the preset parameter limit.

[0066] For example, the second preset time is two seconds. Within two seconds, all the current voltage values obtained are greater than the first wake-up threshold; or, within two seconds, all the current temperature values obtained are greater than the second wake-up threshold; or, within two seconds, all the current voltage values obtained are greater than the first wake-up threshold, and all the current temperature values obtained are greater than the second wake-up threshold.

[0067] The first wake-up threshold includes a preset overcharge threshold of the power battery or a preset over-discharge threshold of the power battery. For example, when the power battery is a ternary battery, the preset overcharge threshold is 4.37V, and the preset over-discharge threshold is 2V, and the specific value can be calibrated. For another example, when the power battery is a lithium iron phosphate battery, the preset overcharge threshold is 3.75V, and the preset over-discharge threshold is 1.8V, and the specific value can be calibrated.

[0068] For example, the second wake-up threshold is 60° C., and the specific value can be calibrated.

[0069] According to some embodiments of the present invention, referring to Figure 2 , S51: If the current voltage value reaches the first wake-up threshold and is maintained for a second preset time, and / or the current temperature value reaches the second wake-up threshold and is maintained for a second preset time, the BMS is woken up and the message sending switch is turned on.

[0070] If the current voltage values ​​obtained within the second preset time reach the first wake-up threshold, and / or the current temperature values ​​obtained within the second preset time reach the second wake-up threshold, the power battery has an abnormal condition and the BMS needs to be woken up. The BMS detects a specific wake-up source or thermal runaway fault mark and sends a specific error code or status mark to the vehicle control system, indicating that operation of the high-voltage system is not allowed, thereby avoiding accidents, reducing damage to the power battery, and ensuring personnel safety.

[0071] According to some embodiments of the present invention, referring to Figure 2 S511: Acquire characteristic parameters of the power battery, and determine whether the characteristic parameters meet the thermal runaway triggering conditions of the vehicle. If the current voltage values ​​acquired within the second preset time reach the first wake-up threshold, and / or the current temperature values ​​acquired within the second preset time reach the second wake-up threshold, then the power battery has an abnormal condition and needs to wake up the BMS. The BMS acquires the characteristic parameters of the power battery and determines the characteristic parameters.

[0072] According to some embodiments of the present invention, referring to Figure 2 If the characteristic parameters meet the thermal runaway triggering conditions of the vehicle, it is determined that the vehicle has a thermal runaway event, and the vehicle is powered off and the thermal runaway is safely handled.

[0073] The thermal runaway detection method also includes: the BMS remains awake, controls the vehicle to power off and sleep, and safely handles thermal runaway events. The BMS can continuously collect parameters of the power battery, monitor the status of the power battery at all times, and safely handle thermal runaway events to prevent the thermal runaway events of the power battery from continuing to spread or spread.

[0074] When a thermal runaway event occurs in the power battery, turn on the message sending switch and report the thermal runaway event. The BMS can perform safety processing on the thermal runaway, including but not limited to: cutting off the circuit connection between the power battery and the load; in the initial stage of the thermal runaway, a special automatic fire extinguishing system can be used to extinguish the power battery, and the fire can be controlled in the initial stage; formulate a detailed emergency plan for the staff, including the emergency evacuation route and the assembly point, to ensure a safe evacuation from the dangerous area in the shortest time.

[0075] If the characteristic parameters do not meet the thermal runaway trigger conditions of the vehicle, the vehicle will be powered off and put into sleep mode after the third preset time. The BMS obtains the characteristic parameters of the power battery and judges the characteristic parameters. If the characteristic parameters do not meet the thermal runaway trigger conditions of the vehicle, it is judged that no thermal runaway event has occurred in the vehicle, then the BMS is turned off, and the network message sending switch is turned off.

[0076] For example, the third preset time is the system preset sleep time.

[0077] According to some embodiments of the present invention, with reference to Figure 2 , if the current voltage value does not reach the first wake-up threshold and remains for the second preset time, and / or, the current temperature value does not reach the second wake-up threshold and remains for the second preset time, the AFE chip will go into sleep mode.

[0078] Within the second preset time, if the current voltage values obtained do not reach the first wake-up threshold, and / or, within the second preset time, if the current temperature values obtained do not reach the second wake-up threshold, it means that no abnormal situation has occurred in the power battery. Then the BMS is turned off, and the vehicle is controlled to be powered off and put into sleep mode.

[0079] In the description of this specification, the description with reference to terms such as "some embodiments", "optionally", "further", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0080] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for detecting thermal runaway of a vehicle, characterized in that: include: Acquire a first voltage value and a first temperature value after the vehicle is powered off; Determining whether the first voltage value is within a first preset range, and / or whether the first temperature value is within a second preset range; If the first voltage value is not within the first preset range, and / or the first temperature value is not within the second preset range, waking up the BMS and maintaining the first preset time; Within the first preset time, characteristic parameters of the power battery are obtained, and it is determined whether the characteristic parameters meet the thermal runaway triggering conditions of the vehicle, and whether a thermal runaway event occurs is determined based on the determination result.

2. The vehicle thermal runaway detection method according to claim 1, characterized in that: If the characteristic parameters meet the thermal runaway triggering conditions of the vehicle, it is determined that a thermal runaway event has occurred in the vehicle, a message sending switch is turned on, and the thermal runaway event is reported.

3. The vehicle thermal runaway detection method according to claim 1, characterized in that: If the characteristic parameters do not meet the thermal runaway triggering conditions of the vehicle, it is determined that no thermal runaway event has occurred in the vehicle, and the entire vehicle is powered off and put into sleep mode after the first preset time.

4. The vehicle thermal runaway detection method according to claim 1, characterized in that: If the first voltage value is within the first preset range, determine whether the current voltage value reaches the first wake-up threshold and is maintained for the second preset time; and / or, if the first temperature value is within the second preset range, determine whether the current temperature value reaches the second wake-up threshold and is maintained for the second preset time.

5. The vehicle thermal runaway detection method according to claim 4, characterized in that: If the current voltage value reaches the first wake-up threshold and is maintained for the second preset time, and / or the current temperature value reaches the second wake-up threshold and is maintained for the second preset time, the BMS is awakened and the message sending switch is turned on.

6. The vehicle thermal runaway detection method according to claim 5, characterized in that: Acquire characteristic parameters of the power battery, and determine whether the characteristic parameters meet a thermal runaway trigger condition of the vehicle.

7. The vehicle thermal runaway detection method according to claim 6, characterized in that: If the characteristic parameters meet the thermal runaway triggering conditions of the vehicle, it is determined that the vehicle has a thermal runaway event and the thermal runaway event is reported; If the characteristic parameters do not meet the thermal runaway triggering conditions of the vehicle, the entire vehicle will be powered off and put into sleep mode after a third preset time.

8. The vehicle thermal runaway detection method according to claim 4, characterized in that: If the current voltage value does not reach the first wake-up threshold and maintains the second preset time, and / or the current temperature value does not reach the second wake-up threshold and maintains the second preset time, the AFE chip goes into sleep mode.

9. The vehicle thermal runaway detection method according to claim 1, characterized in that: The characteristic parameters include: Within a fourth preset time, the temperature rise value of the power battery is greater than the first preset value; Within a fifth preset time, the voltage drop value of the power battery is greater than a second preset value; The temperature difference of the power battery is greater than a third preset value; The temperature of the power battery is greater than a fourth preset value; The voltage of the power battery is less than a fifth preset value; The voltage sampling of the power battery fails; The temperature sampling of the power battery fails; Insulation failure in the power battery pack; AFE chip communication lost failure.

10. The vehicle thermal runaway detection method according to claim 9, characterized in that: The thermal runaway triggering condition includes at least two of the characteristic parameters being triggered.

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