Power battery safety monitoring device and vehicle

Abstract

The present disclosure relates to a power battery safety monitoring device and a vehicle, so as to improve the safety of the power battery of the vehicle. The power battery safety monitoring device includes a power supply, a thermal runaway monitoring circuit, a signal processing circuit and a battery controller; the thermal runaway monitoring circuit is connected to the power supply, and the thermal runaway monitoring circuit includes a safety valve connection line connected in series, and the safety valve connection line is disconnected when the safety valve of the power battery is opened; the signal processing circuit is configured to output a wake-up signal to the battery controller when the safety valve connection line is disconnected; the battery controller is configured to collect the electrical parameter information of the safety valve connection line when detecting the wake-up signal, and determine whether the power battery has a thermal runaway according to the electrical parameter information.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle safety, and in particular, to a power battery safety monitoring device and a vehicle. Background Art

[0002] With the development of battery technology, more and more vehicles begin to use electric energy as the energy source of the vehicle. At the same time, the safety of the power battery is an important consideration. Generally, certain heat is generated when the power battery supplies power. Under normal circumstances, the generated heat does not affect the vehicle safety. However, in abnormal situations, such as collision, overcharging, internal short circuit, etc., the heat generated by the power battery may cause thermal runaway. When thermal runaway occurs, irreversible chemical reactions will occur in the power battery, generating a large amount of combustible and toxic fumes, which may further trigger dangerous situations such as combustion and explosion, threatening the safety of the power battery, the vehicle and the occupants.

[0003] Currently, the monitoring of power battery thermal runaway is mostly simple in form and single in mode. For example, it is monitored by sound or temperature, which is not accurate enough and has great limitations. Moreover, only relying on the battery management system to monitor the current, voltage and temperature to infer the state of the battery, especially in the early stage of thermal runaway, relevant information cannot be obtained in time, reducing the time for the occupants to evacuate safely and unable to ensure sufficient safety. Summary of the Invention

[0004] The purpose of the present disclosure is to provide a power battery safety monitoring device and a vehicle to improve the safety of the vehicle power battery.

[0005] To achieve the above purpose, according to the first aspect of the present disclosure, a power battery safety monitoring device is provided, including a power supply, a thermal runaway monitoring circuit, a signal processing circuit and a battery controller;

[0006] The thermal runaway monitoring circuit is connected to the power supply, and the thermal runaway monitoring circuit includes a safety valve connection line connected in series, and the safety valve connection line is disconnected when the safety valve of the power battery is opened;

[0007] The signal processing circuit is configured to output a wake-up signal to the battery controller when the safety valve connection line is disconnected;

[0008] The battery controller is configured to collect the electrical parameter information of the safety valve connection line when detecting the wake-up signal, and determine whether the power battery has thermal runaway according to the electrical parameter information.

[0009] Optionally, the thermal runaway monitoring circuit includes a first resistor, the safety valve connection line and a second resistor connected in series in sequence;

[0010] One end of the first resistor is connected to the power supply, and the other end of the first resistor is connected to the input end of the safety valve connection line;

[0011] The input end of the safety valve connection line is electrically connected to the metal shell of the safety valve on the first battery cell in the power battery. The metal shell of the Nth battery cell in the power battery is electrically connected to the metal shell of the safety valve on the (N + 1)th battery cell in the power battery. The metal shell of the Mth battery cell in the power battery is electrically connected to the output end of the safety valve connection line, where the power battery includes a total of M battery cells, and 1 ≤ N ≤ M - 1;

[0012] One end of the second resistor is connected to the output end of the safety valve connection line, and the other end of the second resistor is grounded.

[0013] Optionally, the signal processing circuit includes a first signal processing branch and a second signal processing branch;

[0014] The first signal processing branch is disconnected when the safety valve connection line is conducting, and is conducting when the safety valve connection line is disconnected;

[0015] The second signal processing branch is conducting when the first signal processing branch is conducting, and the second signal processing branch outputs the wake-up signal in the conducting state.

[0016] Optionally, the first signal processing branch includes a third resistor, a first N-type MOS transistor, a fourth resistor, and a fifth resistor. One end of the third resistor is connected to the first end of the second resistor, the other end of the third resistor is connected to the gate of the first N-type MOS transistor, one end of the fourth resistor is connected to the power supply, the other end of the fourth resistor is connected to the drain of the first N-type MOS transistor, one end of the fifth resistor is connected to the source of the first N-type MOS transistor, and the other end of the fifth resistor is grounded;

[0017] The second signal processing branch includes a sixth resistor, a second N-type MOS transistor, and a seventh resistor. One end of the sixth resistor is connected to the drain of the first N-type MOS transistor, the other end of the sixth resistor is connected to the gate of the second N-type MOS transistor, one end of the seventh resistor is connected to the source of the second N-type MOS transistor, the other end of the seventh resistor is grounded, the drain of the second N-type MOS transistor is connected to the power supply, and the second signal processing branch outputs the wake-up signal at the connection between the seventh resistor and the source of the second N-type MOS transistor.

[0018] Optionally, the device further includes a self-detection trigger circuit for performing self-detection on the power battery safety monitoring device to determine whether the power battery safety monitoring device can work properly;

[0019] The self - detection trigger circuit includes a P - type MOS transistor. The gate of the P - type MOS transistor is connected to the battery controller. The drain of the P - type MOS transistor is connected to the input end of the safety valve connection line, and the source of the P - type MOS transistor is grounded.

[0020] The battery controller is further configured to send a high - level signal to the gate of the P - type MOS transistor to trigger the self - detection of the power battery safety monitoring device.

[0021] Optionally, the battery controller includes an electrical parameter acquisition component. The electrical parameter acquisition component is connected to the output end of the safety valve connection line. The battery controller is configured to collect the electrical parameter information of the safety valve connection line through the electrical parameter acquisition component.

[0022] Optionally, when the battery controller detects the wake - up signal, it collects the electrical parameter information of the safety valve connection line at a first acquisition frequency through the electrical parameter acquisition component as the first electrical parameter information, and determines whether the power battery has a thermal runaway according to the first electrical parameter information. The first acquisition frequency is greater than a preset frequency.

[0023] Optionally, when the battery controller does not detect the wake - up signal, it collects the electrical parameter information of the safety valve connection line at a second acquisition frequency through the electrical parameter acquisition component as the second electrical parameter information, and determines whether there is an abnormality in each device in the thermal runaway monitoring circuit according to the second electrical parameter information. The second acquisition frequency is less than the preset frequency.

[0024] Optionally, the battery controller stores a parameter upper limit value and a parameter lower limit value;

[0025] The battery controller further includes an abnormality identification component. The abnormality identification component is configured to confirm the abnormality type of the power battery when determining that the parameter value indicated by the second electrical parameter information is greater than the parameter upper limit value or less than the parameter lower limit value; and

[0026] The power battery safety monitoring device further includes a prompt component. The prompt component is configured to output a prompt message according to the abnormality type identified by the abnormality identification component.

[0027] According to a second aspect of the present disclosure, a vehicle is provided, including the power battery safety monitoring device according to the first aspect of the present disclosure.

[0028] Through the above technical solution, the power battery safety monitoring device includes a power supply, a thermal runaway monitoring circuit, a signal processing circuit, and a battery controller. Among them, the thermal runaway monitoring circuit is connected to the power supply, and the thermal runaway monitoring circuit includes a safety valve connection line connected in series, and this safety valve connection line is disconnected when the safety valve of the power battery is opened. The signal processing circuit is used to output a wake-up signal to the battery controller when the safety valve connection line is disconnected, and the battery controller is used to collect the electrical parameter information of the safety valve connection line when detecting the wake-up signal, and determine whether the power battery has a thermal runaway according to the electrical parameter information. Thus, the opening state of the safety valve of the power battery is reflected by the on-off of the safety valve connection line, and this situation can be detected in time when the safety valve of the power battery is opened. Therefore, it is possible to confirm whether the power battery has a thermal runaway faster, and it can be detected in time at the initial stage of the thermal runaway, which is beneficial to making a warning faster and taking protective measures in time, and buying more time for the driver and passengers.

[0029] Other features and advantages of the present disclosure will be described in detail in the following specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0031] Figure 1 It is a schematic diagram of the cell housing when the safety valve is opened;

[0032] Figure 2 It is a schematic diagram of the cell housing after the safety valve is installed;

[0033] Figure 3 It is a block diagram of a power battery safety monitoring device provided according to an embodiment of the present disclosure;

[0034] Figure 4 It is a circuit schematic diagram of a power battery safety monitoring device provided according to an embodiment of the present disclosure;

[0035] Figure 5 It is a schematic diagram of the safety valve connection line in the power battery safety monitoring device of the present disclosure;

[0036] Figure 6 It is a block diagram of a vehicle provided according to an embodiment of the present disclosure.

[0037] DESCRIPTION OF THE REFERENCE NUMERALS

[0038] Power battery safety monitoring device 100, Power supply 110

[0039] Thermal runaway monitoring circuit 120, Signal processing circuit 130

[0040] Battery controller 140, safety valve connection line 121

[0041] First resistor R1, second resistor R2

[0042] Input end A1 of the safety valve connection line, output end A2 of the safety valve connection line

[0043] First signal processing branch 131, second signal processing branch 132 Detailed implementation manners

[0044] The following will describe in detail the specific implementation manners of the present disclosure with reference to the accompanying drawings. It should be understood that the specific implementation manners described herein are only for explaining and understanding the present disclosure, and are not used to limit the present disclosure.

[0045] Before introducing the solution of the present disclosure, the components involved in the solution of the present disclosure will be briefly introduced first.

[0046] The power battery is composed of multiple small batteries, and each small battery can also be called a battery cell. That is to say, the power battery is composed of multiple battery cells. Among them, the electrodes between the battery cells are connected together in series and / or in parallel to meet the requirements of the vehicle for the voltage, discharge current, capacity, etc. of the power battery. The outer shell of the above battery cell is a sealed metal structure to isolate the battery materials inside the battery cell from the outside air.

[0047] During the design and manufacture of the power battery, for each battery cell, in order to prevent its sealed metal outer shell from exploding, a safety valve will be configured for each battery cell as an explosion-proof barrier. Therefore, there is a protruding safety valve port on one side of the metal shell of the battery cell. Through the safety valve port, electrolyte can be added to the battery. A groove is provided near the battery cell side of the safety valve port so that the safety valve cover can be fixed and installed at the card slot position after installation, and a sealing gasket is provided inside the safety valve cover so that a complete seal can be formed through the sealing gasket after the safety valve cover is installed. Since the safety valve is also made of metal, after the safety valve cover is installed, a metal contact can be formed between the safety valve cover and the metal shell of the battery cell, having a conductive effect. Therefore, when the safety valve is installed, it can be fully connected to the metal shell of the battery cell, thus having a good conductive effect. At the same time, when gas is generated inside the battery cell, the gas will generate high pressure in the sealed metal shell. When the safety valve is pushed by the pressure, it will open to release the high air pressure inside the metal shell to prevent a more serious explosion. And after the safety valve is opened, it cannot be restored, and the power battery becomes invalid. Figure 1 It is a schematic diagram of the battery cell shell when the safety valve is opened. Figure 2 It is a schematic diagram of the battery cell shell after the safety valve is installed. Among them, B1 is the battery cell shell, the position indicated by B2 is the card slot position, B3 is the safety valve cover, and B4 is the sealing gasket of the safety valve.

[0048] Figure 3 is a block diagram of a power battery safety monitoring device provided according to an embodiment of the present disclosure. As Figure 1 shown, the power battery safety monitoring device 100 includes a power supply 110, a thermal runaway monitoring circuit 120, a signal processing circuit 130, and a battery controller 140. Among them, the power supply 110 is used to supply power to the power battery safety monitoring device 100. For example, it supplies power to the thermal runaway monitoring circuit 120 and the signal processing circuit 130.

[0049] The thermal runaway monitoring circuit 120 is connected to the power supply 110, and the thermal runaway monitoring circuit 120 includes a safety valve connection line 121 connected in series. The safety valve connection line 121 is disconnected when the safety valve of the power battery is opened.

[0050] The signal processing circuit 130 is used to output a wake-up signal to the battery controller 140 when the safety valve connection line 121 is disconnected.

[0051] The battery controller 140 is used to collect the electrical parameter information of the safety valve connection line 121 when detecting the wake-up signal, and determine whether the power battery has a thermal runaway according to the electrical parameter information.

[0052] Among them, the battery controller 140 can be a battery management system (BMS, Battery Management System).

[0053] Optionally, as Figure 4 shown, the thermal runaway monitoring circuit 120 may include a first resistor R1, a safety valve connection line 121, and a second resistor R2 connected in series in sequence.

[0054] One end of the first resistor R1 is connected to the power supply 110, and the other end of the first resistor R1 is connected to the input terminal A1 of the safety valve connection line 121. The first end of the second resistor R2 is connected to the output terminal A2 of the safety valve connection line 121, and the second end of the second resistor R2 is grounded. Among them, the first resistor R1 and the second resistor R2 play a voltage dividing role in the thermal runaway monitoring circuit 120.

[0055] As described above, the safety valve connection line 121 is disconnected when the safety valve of the power battery is opened, and this can be achieved by connecting the safety valves of the power battery in series in sequence.

[0056] In a possible embodiment, if the power battery includes a total of M battery cells, the input end A1 of the safety valve connection line 121 is electrically connected to the metal shell of the safety valve on the first battery cell in the power battery. The metal shell of the Nth battery cell in the power battery is electrically connected to the metal shell of the safety valve on the (N + 1)th battery cell in the power battery. The metal shell of the Mth battery cell in the power battery is electrically connected to the output end A2 of the safety valve connection line 121. Wherein, 1 ≤ N ≤ M - 1, and both M and N are positive integers.

[0057] In this way, it is equivalent to connecting the cell housing and the safety valve of the next cell with a wire, successively forming a conductive loop of safety valve, cell housing, safety valve, cell housing, safety valve, cell housing (subsequent ones are omitted), and connecting it to the thermal runaway monitoring circuit. If any one of the safety valves is opened, the above loop is disconnected, and the safety valve connection line is disconnected. Therefore, through the connection state of the safety valve connection line, it can quickly and directly reflect whether there is a situation where the safety valve is opened. Among them, the connected wire can be directly welded, can also be bolt-pressed, or can be riveted. The present disclosure does not limit this. Exemplarily, the safety valve connection line can be as Figure 5 shown.

[0058] By the above method, connecting the safety valves in series can monitor the opening of the safety valve faster. At the same time, using a stable electrical signal for monitoring, compared with the existing temperature monitoring method (it is necessary for the temperature to change significantly to sense an abnormality, or it is easy to make mistakes when monitoring at a relatively high overall temperature of the power battery) and the sound monitoring method (it may not be able to monitor the opening of the safety valve in time, or it may make mistakes due to receiving other sound signals), a failure can be detected in time at the initial stage of the opening of the safety valve, and an earlier warning time can be obtained, which is convenient for relevant personnel to take countermeasures. At the same time, using a stable electrical signal, the monitoring accuracy is also guaranteed. In addition, by connecting the safety valves in series, there is no need to additionally install sensors, which can reduce the weight and cost at the same time.

[0059] Optionally, the signal processing circuit 130 may include a first signal processing branch 131 and a second signal processing branch 132. Among them, the first signal processing branch 131 is disconnected when the safety valve connection line 121 is conducting, and is conducting when the safety valve connection line 121 is disconnected. The second signal processing branch 132 is conducting when the first signal processing branch 131 is conducting, and the second signal processing branch 132 outputs a wake-up signal in the conducting state. That is to say, when the safety valve connection line 121 is conducting, the first signal processing branch 131 is disconnected, and the second signal processing branch 132 is also disconnected. That is, if the power battery does not have a thermal runaway and none of the safety valves of the power battery are opened, at this time, the signal processing circuit 130 does not work. Among them, a MOS transistor (MOSFET, Metal Oxide Semiconductor Field Effect Transistor) can be used to control the on / off of the signal processing circuit.

[0060] Exemplarily, as Figure 4 shown, the first signal processing branch 131 may include a third resistor R3, a first N-type MOS transistor S1, a fourth resistor R4, and a fifth resistor R5. One end of the third resistor R3 is connected to the first end of the second resistor R2, and the other end of the third resistor R3 is connected to the gate of the first N-type MOS transistor S1. One end of the fourth resistor R4 is connected to the power supply 110, and the other end of the fourth resistor R4 is connected to the drain of the first N-type MOS transistor S1. One end of the fifth resistor R5 is connected to the source of the first N-type MOS transistor S1, and the other end of the fifth resistor R5 is grounded.

[0061] In Figure 4 the circuit shown, if the safety valve connection line 121 is disconnected, the output terminal A2 of the safety valve connection line 121 outputs a low-level signal (voltage signal), resulting in a low-level signal entering the first signal processing branch 131. After receiving the low-level signal, the first N-type MOS transistor S1 conducts, so that the first signal processing branch 131 conducts. On the contrary, if the safety valve connection line 121 is conducting, the output terminal A2 of the safety valve connection line 121 outputs a high-level signal (voltage signal), resulting in a high-level signal entering the first signal processing branch 131. After receiving the high-level signal, the first N-type MOS transistor S1 turns off (does not conduct), so that the first signal processing branch 131 is disconnected (does not work).

[0062] Exemplarily, as Figure 4As shown, the second signal processing branch 132 includes a sixth resistor R6, a second N-type MOS transistor S2, and a seventh resistor R7. One end of the sixth resistor R6 is connected to the drain of the first N-type MOS transistor S1, the other end of the sixth resistor R6 is connected to the gate of the second N-type MOS transistor S2, one end of the seventh resistor R7 is connected to the source of the second N-type MOS transistor S2, the other end of the seventh resistor R7 is grounded, and the drain of the second N-type MOS transistor S2 is connected to the power supply 110. Moreover, the second signal processing branch 132 outputs a wake-up signal at the connection point K between the seventh resistor R7 and the source of the second N-type MOS transistor S2.

[0063] In Figure 4 the circuit shown, if the safety valve connection line 121 is disconnected, the first signal processing branch 131 conducts, resulting in a low-level signal entering the second signal processing branch 132. The second N-type MOS transistor S2 conducts at a low level. Thus, the second signal processing branch 132 conducts, and the connection point K between the seventh resistor R7 and the source of the second N-type MOS transistor S2 is at a high level at this time. Therefore, the second signal processing branch 132 outputs a high-level wake-up signal (alternatively, the battery controller 140 can also actively collect at the connection point K). Conversely, if the safety valve connection line 121 is conducting, the first signal processing branch 131 is disconnected, and the second signal processing branch 132 is also disconnected. At this time, if the signal at point K is collected, only a low-level signal can be collected.

[0064] Actually, the signal processing circuit 130 is used to amplify signals. Among them, the first signal processing branch 131 is responsible for the first-stage amplification, and the second signal processing branch 132 is responsible for the second-stage amplification to output a larger wake-up signal.

[0065] Optionally, the battery controller 140 may include an electrical parameter collection component. The electrical parameter collection component can be connected to the output terminal A2 of the safety valve connection line 121. The battery controller 140 is used to collect the electrical parameter information of the safety valve connection line 121 through the electrical parameter collection component. For example, at the AD1 position in Figure 4 a collection point can be set, and the battery controller 140 can collect the electrical parameters at the collection point AD1 through the electrical parameter collection component to obtain the electrical parameter information of the safety valve connection line 121. For example, the electrical parameter information can be a voltage signal, or it can also be a current signal, etc.

[0066] The battery controller 140 can be used to collect the electrical parameter information of the safety valve connection line 121 as the first electrical parameter information at the first collection frequency through the electrical parameter collection component when detecting the wake-up signal, and determine whether the power battery has a thermal runaway according to the first electrical parameter information.

[0067] Among them, the first acquisition frequency is greater than the preset frequency. That is to say, the first acquisition frequency can be set higher to achieve high-frequency acquisition of electrical parameter information. If the battery controller 140 detects a wake-up signal, it indicates that the safety valve may be opened. Therefore, at this time, higher-frequency information acquisition is required to confirm whether the safety valve is actually opened, so as to detect the thermal runaway of the power battery more quickly.

[0068] When determining whether the power battery has a thermal runaway based on the first electrical parameter information, it can be determined whether the collected first electrical parameter information (for example, the electrical parameter information collected at AD1 in Figure 4 is a low-level signal. If it is determined to be a low-level signal, it indicates that the connection line 121 of the safety valve is disconnected (there is an opened safety valve). Therefore, it can be confirmed that the power battery has a thermal runaway. Moreover, in order to more accurately determine the thermal runaway, as much first electrical parameter information as possible can be collected and judged multiple times. When it is confirmed multiple times (the number of times can be preset) that a low-level signal is collected, it can be confirmed that the power battery has a thermal runaway.

[0069] Optionally, the battery controller 140 is configured to collect the electrical parameter information of the safety valve connection line at the second acquisition frequency through the electrical parameter acquisition component as the second electrical parameter information when no wake-up signal is detected, and determine whether there is an abnormality in each device in the thermal runaway monitoring circuit 120 according to the second electrical parameter information.

[0070] In the already set power battery safety monitoring device, if all devices and the connection relationships between devices are normal, the collected electrical parameter information should be stable. Therefore, as long as the electrical parameters are too high or too low, it may indicate an abnormal situation. Therefore, the parameter upper limit value and the parameter lower limit value can be preset to limit the range of normal electrical parameters. Thus, if the parameter value indicated by the collected second electrical parameter information exceeds the parameter upper limit value, or is lower than the parameter lower limit value, it indicates that there may be an abnormality in the devices in the thermal runaway monitoring circuit 120. At the same time, the battery controller 140 may further include an abnormality identification component, which is configured to confirm the type of abnormality of the power battery when it is determined that the parameter value indicated by the second electrical parameter information is greater than the parameter upper limit value, or less than the parameter lower limit value, that is, to confirm what kind of abnormality the power battery actually has.

[0071] Moreover, the power battery safety monitoring device 100 may further include a prompt component, which is configured to output a prompt message according to the type of abnormality identified by the abnormality identification component.

[0072] For example, if the second electrical parameter information collected multiple times is higher than the pre-set parameter upper limit value, the abnormality recognition component can further collect the temperature information and / or voltage information of the battery cell to confirm whether the temperature and / or voltage of the battery cell is normal. If the temperature information and / or voltage information of the battery cell is abnormal, it indicates that there may be a leakage abnormality inside the battery cell. At this time, the prompt component can output corresponding prompt information (for example, output through an instrument, output through a sound playback device, etc.) to prompt for circuit maintenance of the power battery safety monitoring device.

[0073] For another example, if the second electrical parameter information collected multiple times is lower than the pre-set parameter lower limit value, the abnormality recognition component can further collect the relevant electrical parameters of the safety valve connection line 121 and calculate the resistance of the safety valve. If it is determined that the resistance of the safety valve increases, it indicates that there may be corrosion at the connection of the safety valve. At this time, the prompt component can output corresponding prompt information (for example, output through an instrument, output through a sound playback device, etc.) to prompt for circuit maintenance of the power battery safety monitoring device.

[0074] For another example, assuming that the second electrical parameter information is a voltage signal, if the second electrical parameter information collected multiple times is lower than the pre-set parameter lower limit value, the abnormality recognition component can record the duration of this situation. If the duration of the situation where it is lower than the parameter lower limit value has reached the preset duration, it indicates that it may be that the battery cell inside the power battery crystallizes at the negative electrode, resulting in a battery short circuit. At this time, the prompt component can output corresponding prompt information (for example, output through an instrument, output through a sound playback device, etc.) to early warn of the thermal runaway hidden danger of the power battery safety. In this way, an early warning can be made before the thermal runaway occurs, reminding relevant personnel to handle it and avoiding the occurrence of thermal runaway.

[0075] For another example, assuming that the second electrical parameter information is a voltage signal, if the second electrical parameter information collected multiple times is higher than the pre-set parameter upper limit value, the abnormality recognition component can record the duration of this situation. If the duration of the situation where it is higher than the parameter upper limit value has reached the preset duration, it indicates that it may be that the battery cell inside the power battery crystallizes at the positive electrode, resulting in a battery short circuit. At this time, the prompt component can output corresponding prompt information (for example, output through an instrument, output through a sound playback device, etc.) to early warn of the thermal runaway hidden danger of the power battery safety. In this way, an early warning can be made before the thermal runaway occurs, reminding relevant personnel to handle it and avoiding the occurrence of thermal runaway.

[0076] Among them, the second acquisition frequency is less than the preset frequency, that is, less than the first acquisition frequency. That is to say, under normal circumstances, the battery controller 140 can acquire the second electrical parameter information at a low frequency to confirm the status of each device in the thermal runaway monitoring circuit 120, while avoiding excessive data processing and saving power. When a wake-up signal is detected, since the safety valve may have been opened, the battery controller 140 can switch to acquiring the first electrical parameter information at a high frequency to quickly confirm whether the safety valve has indeed been opened.

[0077] As described above, if the vehicle usually acquires electrical parameter information at a low speed, the wake-up signal generated by the power battery safety monitoring device can wake up the battery controller to acquire the electrical parameter information at a high speed. Compared with the currently commonly used methods of timed wake-up and detection, there is no need to additionally set up wake-up devices, which can not only achieve low-speed acquisition under normal circumstances but also meet the high-speed acquisition requirements for quick judgment. In this way, the performance of thermal runaway monitoring can be improved on the premise of saving device cost and volume.

[0078] Through the above technical solution, the power battery safety monitoring device includes a power supply, a thermal runaway monitoring circuit, a signal processing circuit, and a battery controller. Among them, the thermal runaway monitoring circuit is connected to the power supply, and the thermal runaway monitoring circuit includes a safety valve connection line connected in series. This safety valve connection line is disconnected when the safety valve of the power battery is opened. The signal processing circuit is used to output a wake-up signal to the battery controller when the safety valve connection line is disconnected. The battery controller is used to acquire the electrical parameter information of the safety valve connection line when a wake-up signal is detected and determine whether the power battery has a thermal runaway according to the electrical parameter information. Thus, the opening state of the power battery safety valve is reflected by the on / off of the safety valve connection line, and this situation can be detected in time when the safety valve of the power battery is opened. Therefore, it is possible to more quickly confirm whether the power battery has a thermal runaway and detect it in the initial stage of the thermal runaway, which is beneficial to making a warning more quickly and taking protection measures in time, and winning more time for the passengers and drivers.

[0079] Optionally, the power battery safety monitoring device 100 may further include a self-detection trigger circuit for self-detecting the power battery safety monitoring device 100 to determine whether the power battery safety monitoring device 100 can work normally.

[0080] As Figure 4 shown, the self-detection trigger circuit may include a P-type MOS transistor S3. The gate of the P-type MOS transistor S3 is connected to the battery controller 140. The drain of the P-type MOS transistor S3 is connected to the input terminal A1 of the safety valve connection line 121. The source of the P-type MOS transistor S3 is grounded.

[0081] The battery controller 140 is also used to send a high-level signal to the gate of the P-type MOS transistor S3 to trigger the self-detection of the power battery safety monitoring device 100.

[0082] After the gate of the P-type MOS transistor S3 receives the high-level signal, due to the characteristics of the P-type MOS transistor, the P-type MOS transistor S3 conducts, and the safety valve connection line 121 is equivalent to being grounded. At this time, the scenario where the safety valve connection line 121 is disconnected can be simulated, and it can be self-detected whether the power battery safety monitoring device 100 can trigger the corresponding processing process normally.

[0083] After the above self-detection is triggered, the processing process is the same as the case where the safety valve connection line 121 is disconnected, and details are not described here again.

[0084] When the detection is repeated multiple times and the power battery safety monitoring device can complete the processing process normally, it can be confirmed that the power battery safety monitoring device passes the detection. During the detection process, if the electrical parameters do not match the expectations (for example, the electrical parameter information collected at the acquisition point AD1 does not match the expected normal parameters), it indicates that there may be problems such as aging and faults in the power battery safety monitoring device. At this time, the battery controller can output corresponding prompt information to prompt for circuit maintenance of the power battery safety monitoring device. Among them, the self-detection process can be triggered regularly to regularly detect whether the power battery safety monitoring device can work normally.

[0085] Optionally, the power battery safety monitoring device 100 may further include a protection device for preventing the voltage of the thermal runaway monitoring circuit from being too large, thereby protecting the thermal runaway monitoring circuit. Exemplarily, the protection device can use a zener diode. As Figure 4 shown, one end of the protection device D1 can be connected to the output end A2 of the safety valve connection line 121, and the other end of the protection device is grounded, which is used to limit the voltage reaching the second resistor R2 and protect the subsequent circuit.

[0086] Optionally, the power battery safety monitoring device 100 may further include a stabilizing device for eliminating fluctuations and interferences generated by the circuit. Exemplarily, the stabilizing device can use a capacitor. As Figure 4 shown, one end of the capacitor C1 is connected to the output end A2 of the safety valve connection line 121, and the other end is grounded, which is used to eliminate fluctuations and interferences generated on the thermal runaway monitoring circuit 120. One end of the capacitor C2 is connected to the gate of the second N-type MOS transistor S2, and the other end is grounded, which is used to eliminate fluctuations and interferences generated on the second signal processing branch.

[0087] As Figure 6 shown, the present disclosure also provides a vehicle including the power battery safety monitoring device 100 according to any embodiment of the present disclosure.

[0088] Optionally, the vehicle provided by the present disclosure may further include a thermal runaway handling component, which is configured to handle thermal runaway faults when it is determined that a power battery has a thermal runaway. Among them, the thermal runaway fault handling may include, but is not limited to, the following: vehicle instrument alarm, external acoustic and optical alarm, remote alarm, cooling the battery, monitoring the temperature of the power battery cells, and controlling the vehicle to stop.

[0089] Among them, the thermal runaway handling component can communicate with the corresponding devices on the vehicle. For example, if the thermal runaway fault handling includes a vehicle instrument alarm, the thermal runaway handling component can communicate with the vehicle instrument to inform the vehicle instrument to give an alarm. For another example, if the thermal runaway fault handling includes cooling the battery, the thermal runaway handling component can communicate with the vehicle air conditioner to enable the air conditioner to turn on the cooling mode and indirectly cool the battery. For another example, if the vehicle is in a driving state, in order to ensure vehicle safety, the thermal runaway fault handling can include controlling the vehicle to stop. Thus, the thermal runaway handling component can communicate with the motor controller to reduce the motor power and achieve parking.

[0090] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0091] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without conflict. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.

[0092] In addition, any combination can be made between various different embodiments of the present disclosure, as long as it does not violate the idea of the present disclosure, it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A power battery safety monitoring device, characterized in that, It includes a power supply, a thermal runaway monitoring circuit, a signal processing circuit and a battery controller; The thermal runaway monitoring circuit is connected to the power supply, and the thermal runaway monitoring circuit includes a safety valve connection line connected in series, and the safety valve connection line is disconnected when the safety valve of the power battery is opened; The signal processing circuit is used to output a wake-up signal to the battery controller when the safety valve connection line is disconnected; The battery controller is used to collect the electrical parameter information of the safety valve connection line when detecting the wake-up signal, and determine whether the power battery has a thermal runaway according to the electrical parameter information; The input end of the safety valve connection line is electrically connected to the metal shell of the safety valve on the first cell in the power battery, the metal shell of the Nth cell in the power battery is electrically connected to the metal shell of the safety valve on the (N + 1)th cell in the power battery, and the metal shell of the Mth cell in the power battery is electrically connected to the output end of the safety valve connection line, where the power battery contains M cells in total, and 1 ≤ N ≤ M - 1.

2. The device according to claim 1, characterized in that, The thermal runaway monitoring circuit includes a first resistor, the safety valve connection line and a second resistor connected in series in sequence; One end of the first resistor is connected to the power supply, and the other end of the first resistor is connected to the input end of the safety valve connection line; The first end of the second resistor is connected to the output end of the safety valve connection line, and the second end of the second resistor is grounded.

3. The device according to claim 2, wherein The signal processing circuit includes a first signal processing branch and a second signal processing branch; The first signal processing branch is disconnected when the safety valve connection line is conducting, and is conducting when the safety valve connection line is disconnected; The second signal processing branch is conducting when the first signal processing branch is conducting, and the second signal processing branch outputs the wake-up signal in the conducting state.

4. The device according to claim 3, wherein, The first signal processing branch includes a third resistor, a first N-type MOS transistor, a fourth resistor and a fifth resistor. One end of the third resistor is connected to the first end of the second resistor, the other end of the third resistor is connected to the gate of the first N-type MOS transistor, one end of the fourth resistor is connected to the power supply, the other end of the fourth resistor is connected to the drain of the first N-type MOS transistor, one end of the fifth resistor is connected to the source of the first N-type MOS transistor, and the other end of the fifth resistor is grounded; The second signal processing branch includes a sixth resistor, a second N-type MOS transistor and a seventh resistor. One end of the sixth resistor is connected to the drain of the first N-type MOS transistor, the other end of the sixth resistor is connected to the gate of the second N-type MOS transistor, one end of the seventh resistor is connected to the source of the second N-type MOS transistor, the other end of the seventh resistor is grounded, the drain of the second N-type MOS transistor is connected to the power supply, and the second signal processing branch outputs the wake-up signal at the connection between the seventh resistor and the source of the second N-type MOS transistor.

5. The device according to claim 2, characterized in that, The device further includes a self - detection trigger circuit for self - detecting the power battery safety monitoring device to determine whether the power battery safety monitoring device can work properly; The self - detection trigger circuit includes a P - type MOS transistor. The gate of the P - type MOS transistor is connected to the battery controller. The drain of the P - type MOS transistor is connected to the input end of the safety valve connection line. The source of the P - type MOS transistor is grounded; The battery controller is further configured to send a high - level signal to the gate of the P - type MOS transistor to trigger the self - detection of the power battery safety monitoring device.

6. The device according to claim 1, characterized in that The battery controller includes an electrical parameter acquisition component. The electrical parameter acquisition component is connected to the output end of the safety valve connection line. The battery controller is used to acquire the electrical parameter information of the safety valve connection line through the electrical parameter acquisition component.

7. The device according to claim 6, characterized in that, The battery controller is configured to acquire the electrical parameter information of the safety valve connection line as first electrical parameter information at a first acquisition frequency through the electrical parameter acquisition component when the wake - up signal is detected, and determine whether the power battery has a thermal runaway according to the first electrical parameter information. The first acquisition frequency is greater than a preset frequency.

8. The device according to claim 6, characterized in that, The battery controller is configured to acquire the electrical parameter information of the safety valve connection line as second electrical parameter information at a second acquisition frequency through the electrical parameter acquisition component when the wake - up signal is not detected, and determine whether there is an abnormality in each device in the thermal runaway monitoring circuit according to the second electrical parameter information. The second acquisition frequency is less than the preset frequency.

9. The device according to claim 8, characterized in that, The battery controller stores a parameter upper limit value and a parameter lower limit value; The battery controller further includes an abnormality identification component. The abnormality identification component is configured to confirm the abnormality type of the power battery when it is determined that the parameter value indicated by the second electrical parameter information is greater than the parameter upper limit value or less than the parameter lower limit value; and, The power battery safety monitoring device further includes a prompt component. The prompt component is configured to output a prompt message according to the abnormality type identified by the abnormality identification component.

10. A vehicle, characterized in that, Including the power battery safety monitoring device according to any one of claims 1 - 9.

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