How to detect sudden thermal fluctuations in device batteries and readable data storage media.

Abstract

Invention details;

Description

Battery sudden thermal runaway monitoring method, device and readable storage medium

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on June 25, 2021, with application number 202110711799.5 and invention name “Battery Sudden Thermal Runaway Monitoring Method, Device and Readable Storage Medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery management technology, and in particular to a method, device, and readable storage medium for monitoring sudden thermal runaway of a battery. Background Art

[0003] Batteries are widely used in electronic products such as mobile phones, laptops, and electric shavers, as well as in electric vehicles, energy storage power stations, and base station power supplies. However, they have also been the cause of numerous fires and explosions. Generally, a short circuit within a battery causes abnormal self-discharge, which gradually develops into thermal runaway (which can take hours, days, or even longer). However, sometimes, thermal runaway does not proceed through a prolonged developmental phase, but rather occurs instantaneously or within seconds, commonly known as "sudden death" thermal runaway.

[0004] In addition to sudden thermal runaways that can occur during battery use, they can also occur during production. For example, if a battery has design or manufacturing defects, sudden thermal runaways can occur during processes like formation, capacity separation, and high-temperature aging. This can pose significant safety risks to adjacent batteries, equipment, and production facilities on the production line. Therefore, it's essential to monitor battery thermal runaways to provide timely warnings when they occur and ensure battery safety.

[0005] Summary of the Invention

[0006] The purpose of this application is to provide a battery sudden thermal runaway monitoring method, device and readable storage medium to provide early warning of battery sudden thermal runaway, thereby effectively ensuring the safety of the battery.

[0007] To achieve the above objectives, the present application provides, in a first aspect, a method for monitoring sudden thermal runaway of a battery, comprising:

[0008] Obtaining current thermal runaway-related parameters of the battery in a target operating mode, the current thermal runaway-related parameters including at least one of a first parameter for characterizing a voltage change parameter under a current change in power, a second parameter for characterizing a temperature change parameter under the current change in power, and a third parameter for characterizing a temperature change parameter under the current change in voltage;

[0009] Obtaining a parameter threshold corresponding to the current thermal runaway related parameter in a preset thermal runaway related parameter correspondence relationship under the target operating mode;

[0010] Monitor whether the battery has a thermal runaway risk based on the current thermal runaway related parameter and the parameter threshold.

[0011] Optionally, the method further includes:

[0012] determining whether the current voltage of the battery is within a preset voltage range;

[0013] The monitoring of whether the battery has a thermal runaway risk according to the current thermal runaway related parameter and the parameter threshold includes:

[0014] If it is within the preset voltage range, the battery is monitored for thermal runaway risk based on the current thermal runaway related parameters obtained this time, the thermal runaway related parameters obtained last time, and the relationship between the parameter thresholds.

[0015] Optionally, the current thermal runaway related parameter is the first parameter, and the corresponding relationship of the thermal runaway related parameter is a first corresponding relationship between a ratio of a changing voltage to a changing power and the battery power; the first corresponding relationship is determined by:

[0016] determining a change in the amount of electricity of the battery according to the maximum capacity of the battery;

[0017] In the target operating mode, each time the battery charges or discharges the variable electrical quantity, a first variable voltage generated by the battery under the variable electrical quantity is collected;

[0018] The first corresponding relationship is determined according to a ratio of the first changed voltage to the changed power and the battery power.

[0019] Optionally, the current thermal runaway related parameter is the second parameter, and the thermal runaway related parameter correspondence is a second correspondence between a ratio of a changing temperature to a changing power and the battery power; the second correspondence is determined by:

[0020] determining a change in the amount of electricity of the battery according to the maximum capacity of the battery;

[0021] In the target operating mode, each time the battery charges or discharges the variable amount of electricity, a temperature change generated by the battery under the variable amount of electricity is collected;

[0022] The second corresponding relationship is determined according to the ratio of the changed temperature to the changed power and the battery power.

[0023] Optionally, the current thermal runaway related parameter is the third parameter, and the corresponding relationship of the thermal runaway related parameter is a third corresponding relationship between a ratio of the changing temperature to the second changing voltage and the battery voltage; the third corresponding relationship is determined by:

[0024] determining a second changed voltage of the battery according to a charge cut-off voltage and a discharge cut-off voltage of the battery;

[0025] In the target operating mode, each time the battery charges or discharges the second variable voltage, a temperature change generated by the battery under the variable power is collected;

[0026] The third corresponding relationship is determined according to the ratio of the changed temperature to the second changed voltage and the battery voltage.

[0027] Optionally, the method further includes:

[0028] In response to receiving an update request for the thermal runaway related parameter correspondence, obtaining a target thermal runaway related parameter correspondence;

[0029] Determining the target thermal runaway related parameter correspondence relationship as a preset thermal runaway related parameter correspondence relationship;

[0030] Wherein, when the battery is in the production stage, the target thermal runaway related parameter correspondence relationship is a thermal runaway related parameter correspondence relationship determined based on other batteries that have been produced and have normal performance;

[0031] When the battery is in use, the target thermal runaway-related parameter correspondence is a thermal runaway-related parameter correspondence determined according to a historical charging or discharging process of the battery.

[0032] Optionally, monitoring whether the battery has a thermal runaway risk based on the current thermal runaway-related parameter and the parameter threshold includes:

[0033] If the difference between the current thermal runaway related parameter and the parameter threshold exceeds a preset range, it is determined that the battery has a thermal runaway risk.

[0034] Optionally, the method further includes:

[0035] When it is determined that the battery has a risk of thermal runaway, outputting a prompt message for instructing to stop charging or discharging, and / or outputting a thermal runaway warning signal; and / or

[0036] If it is determined that the battery has a risk of thermal runaway, a cooling or fire-fighting action is triggered.

[0037] A second aspect of the present application provides a battery sudden thermal runaway monitoring device, comprising:

[0038] a first acquisition module, configured to acquire current thermal runaway-related parameters of the battery in a target operating mode, the current thermal runaway-related parameters including at least one of a first parameter for characterizing a voltage variation parameter under a current change in electrical quantity, a second parameter for characterizing a temperature variation parameter under a current change in electrical quantity, and a third parameter for characterizing a temperature variation parameter under a current change in voltage;

[0039] A second acquisition module is configured to acquire a parameter threshold value corresponding to the current thermal runaway related parameter from a preset thermal runaway related parameter correspondence relationship under the target operating mode;

[0040] A monitoring module is used to monitor whether the battery has a thermal runaway risk based on the current thermal runaway related parameters and the parameter threshold.

[0041] The third aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method provided in the first aspect of the present application.

[0042] A fourth aspect of the present application provides an electronic device, including:

[0043] a memory having a computer program stored thereon;

[0044] A processor is used to execute the computer program in the memory to implement the steps of the method provided in the first aspect of the present application.

[0045] The above technical solution monitors battery thermal runaway based on the battery's current thermal runaway-related parameters in the target operating mode and the parameter thresholds corresponding to these parameters. This allows for early detection of thermal runaway, effectively preventing it and ensuring battery safety. Furthermore, since there's no need to exploit differences between battery cells within a series battery pack to monitor thermal runaway, the accuracy of sudden thermal runaway monitoring is unaffected by inconsistencies between individual cells, improving the accuracy of monitoring for sudden thermal runaway.

[0046] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings are used to provide further understanding of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present application, but do not constitute a limitation to the present application.

[0048] FIG1 is a flow chart showing a method for monitoring a battery thermal outage according to an exemplary embodiment.

[0049] FIG2 is a flow chart showing another method for monitoring sudden thermal runaway of a battery according to an exemplary embodiment.

[0050] FIG3 is a block diagram of a battery sudden thermal runaway monitoring device according to an exemplary embodiment.

[0051] Fig. 4 is a block diagram of an electronic device according to an exemplary embodiment. DETAILED DESCRIPTION

[0052] In related technologies, the method of diagnosing battery faults based on voltage differences, temperature differences, and SOC (State of Charge) differences between cells in a battery pack is mainly used to diagnose battery micro-short circuits and warn of thermal runaway, which takes a long time to develop. Generally, the diagnosis takes a long time, and sometimes large changes in voltage and temperature are required to warn of the fault. It is impossible to warn of sudden battery thermal runaway.

[0053] For example, an internal short-circuit detection algorithm is proposed for a series battery pack. This diagnostic method requires comparing each battery cell in the series battery pack and calculating the position or slope of the dQ / dV characteristic peak (where dQ represents the change in battery charge and dV represents the change in battery voltage) as a feature. However, the dQ / dV characteristic peak can generally only be obtained under low-rate current conditions. Under high-rate charge and discharge conditions, the dQ / dV characteristic peak will weaken or even disappear. In addition, as the battery ages, some peaks will also disappear. Therefore, the above-mentioned internal short-circuit detection algorithm cannot accurately monitor the thermal runaway of the battery. Moreover, in the related art, it is impossible to warn of the thermal runaway of the battery in advance, and thus the battery safety cannot be guaranteed.

[0054] In view of this, the present application provides a battery sudden thermal runaway monitoring method, device and readable storage medium to provide early warning of battery sudden thermal runaway, thereby effectively ensuring the safety of the battery.

[0055] The following describes the specific embodiments of the present application in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0056] FIG1 is a flow chart showing a method for monitoring sudden thermal runaway of a battery according to an exemplary embodiment. As shown in FIG1 , the method may include the following steps.

[0057] In step 101, current thermal runaway related parameters of the battery in the target operating mode are obtained, and the current thermal runaway related parameters include at least one of a first parameter for characterizing a voltage change parameter under a current change in power, a second parameter for characterizing a temperature change parameter under a current change in power, and a third parameter for characterizing a temperature change parameter under a current change in voltage.

[0058] The first parameter can be the voltage change parameter dV under the current change in power dQ, or it can be the ratio dV / dQ of the voltage change parameter dV to the current change in power dQ. Similarly, the second parameter can be the temperature change parameter dT under the current change in power dQ, or it can be the ratio of the temperature change parameter dT to the current change in power dQ. The third parameter can be the temperature change parameter dT under the current change in voltage dv, or it can be the ratio dT / dv of the temperature change parameter dT to the current change in voltage dv (wherein, each time the third parameter is calculated, the current change in voltage dv of the battery is a fixed voltage change calculated in advance). This application does not specifically limit the first parameter, the second parameter and the third parameter. In addition, the target operating mode can be any one of constant current charging, constant current discharging, constant power charging, constant power discharging, and pulse charging mode.

[0059] In step 102, a parameter threshold corresponding to a current thermal runaway related parameter is obtained from a preset thermal runaway related parameter correspondence in a target operating mode.

[0060] In the present application, the correspondence relationship between the thermal runaway related parameters in the target working mode is pre-set. In this way, after the current thermal runaway related parameters in the target working mode are obtained in step 101, the parameter threshold corresponding to the current thermal runaway related parameter can be obtained from the pre-set correspondence relationship between the thermal runaway related parameters.

[0061] In step 103, the battery is monitored for thermal runaway risk based on current thermal runaway related parameters and parameter thresholds.

[0062] For example, if the difference between the current thermal runaway related parameter and the parameter threshold exceeds a preset range, it is determined that the battery has a thermal runaway risk.

[0063] It is worth noting that the inventors obtained the voltage change curves of the battery during the 12 charging processes respectively, and found that at the end of the last charge (the 12th time), a sudden thermal runaway occurred at the same time as the voltage dropped. Although the voltage showed a slight abnormality at around 4.076V, the voltage deviation from the previous charge and discharge cycle was around 10mV. However, since it is common for battery cells in a battery pack to have a deviation of tens of mV between them, it is impossible to identify the thermal runaway anomaly by the difference in cell voltage. On the contrary, the inventors obtained the dV / dQ curves of the battery during the 12 charging processes respectively. From the 12 dV / dQ curves, it can be found that the dV / dQ value showed obvious abnormalities before the battery voltage suddenly dropped. Based on this, the battery's sudden thermal runaway can be monitored four minutes in advance. Therefore, monitoring the battery's sudden thermal runaway through the battery's dV / dQ curve can achieve the purpose of early warning.

[0064] In addition, the inventors obtained the temperature change curves of the battery during the 12 charging processes respectively, and found that after the temperature at the end of the 12th charge was 2 to 3 degrees Celsius different from the temperature during the previous charge, the battery instantly caught fire and exploded. However, even if the temperature of each battery can be collected on the actual vehicle, it is very common for there to be a temperature difference of about 5 degrees Celsius between each cell in the actual vehicle environment. Therefore, for battery packs or electric vehicles, it is impossible to provide an early warning of thermal runaway based on the temperature difference between cells. On the contrary, the inventors obtained the dT / dQ curves of the battery during the 12 charging processes respectively, and found that the dT / dQ value showed obvious abnormalities before the voltage suddenly dropped. Based on this, the battery's sudden thermal runaway can be monitored three minutes in advance. Therefore, monitoring the battery's sudden thermal runaway through the battery's dT / dQ curve can achieve the purpose of early warning.

[0065] Similarly, the inventors obtained the dT / dv curves of the battery during 12 charging cycles (wherein, during each charging cycle, multiple dT / dv values ​​were calculated, and during each calculation, the battery's current voltage change dv was a pre-calculated fixed voltage change). They found that the dT / dv value showed obvious abnormalities before a sudden voltage drop, which allowed them to detect sudden thermal runaway of the battery three minutes in advance. Therefore, monitoring sudden thermal runaway of the battery using the battery's dT / dv curve can achieve the purpose of early warning.

[0066] The above technical solution monitors battery thermal runaway based on the battery's current thermal runaway-related parameters in the target operating mode and the parameter thresholds corresponding to these parameters. This allows for early detection of thermal runaway, effectively preventing it and ensuring battery safety. Furthermore, since there's no need to exploit differences between battery cells within a series battery pack to monitor thermal runaway, the accuracy of sudden thermal runaway monitoring is unaffected by inconsistencies between individual cells, improving the accuracy of this monitoring.

[0067] The following describes in detail the method for determining the corresponding relationship between the preset thermal runaway related parameters in the target operating mode.

[0068] In one embodiment, the current thermal runaway related parameter is the first parameter dV / dQ. Accordingly, the corresponding relationship of the thermal runaway related parameter is a first corresponding relationship between the ratio of the changing voltage to the changing power and the battery power. The first corresponding relationship can be determined in the following manner.

[0069] (1) Determine the battery's change in capacity based on its maximum capacity.

[0070] For example, the battery's maximum capacity Q is divided by n to obtain the battery's change in charge dQ, where n is generally 100.

[0071] (2) In the target working mode, each time the battery changes its charge or discharge capacity, the first change voltage generated by the battery under the change in capacity is collected.

[0072] (3) Determine a first corresponding relationship according to the ratio of the first changed voltage to the changed power and the battery power.

[0073] It is worth noting that the first parameter dV / dQ obtained in step 101 in Figure 1 is obtained when the battery is in the target operating mode. Therefore, the first corresponding relationship between the ratio of the changing voltage to the changing power and the battery power is also determined in the target operating mode.

[0074] If the target operating mode is any of constant current charging, constant power charging, and pulse charging modes, each time the battery is charged to dQ of power, the battery voltage after charging to that power is subtracted from the battery voltage before charging to obtain a first change voltage dV. The battery is charged until the charging cut-off voltage, and n dVs can be obtained. After that, each dV is divided by dQ to obtain n dV / dQ values. That is, the dV / dQ values ​​are obtained when the power changes from 0 to dQ, dQ to 2dQ, ..., (n-1)dQ to ndQ. Finally, the first corresponding relationship between the ratio of the change voltage to the change power and the battery power is obtained by interpolation.

[0075] If the target operating mode is constant current discharge or constant power discharge mode, discharge starts from the battery charge cut-off voltage. Every time the battery discharges dQ of electricity, the battery voltage after discharge is subtracted from the battery voltage before discharge to obtain the first change voltage dV. The battery is discharged until the discharge cut-off voltage, and n dVs can be obtained. After that, each dV is divided by dQ to obtain n dV / dQ values. That is, the dV / dQ values ​​are obtained when the electricity goes from 0 to dQ, dQ to 2dQ, ..., (n-1)dQ to ndQ. Finally, the first correspondence between the ratio of the change voltage to the change in electricity and the battery electricity is obtained by interpolation.

[0076] It is worth noting that the battery used to determine the first corresponding relationship is a battery that has not experienced thermal runaway, and the battery can be the same battery as the battery mentioned in each step in Figure 1, or can be batteries from the same batch. This application does not limit this.

[0077] In this embodiment, when monitoring the thermal runaway of the battery, when the battery is charging or discharging, the battery power Q is first obtained through the battery monitoring system. i and voltage V i Then, the battery is charged or discharged for a certain amount of electricity dQ, and the voltage V after charging or discharging a certain amount of electricity dQ is obtained. i+1 , then the voltage V i+1 Subtract voltage V i Get the current change in power (from Q i Change to Q i ±dQ) under the voltage change parameter dV (from V i Change to V i+1 ), and the voltage change parameter dV and the current change in power (from Q i Change to Q i ±dQ) is determined as the first parameter.

[0078] Finally, from the pre-stored first correspondence, it is determined that the power output is from Q i Change to Q i The dV / dQ value at ±dQ is determined as a parameter threshold corresponding to the first parameter. When the difference between the first parameter and the parameter threshold exceeds a preset range, it is determined that the battery has a thermal runaway risk.

[0079] In another embodiment, the current thermal runaway related parameter is the second parameter dT / dQ. Accordingly, the corresponding relationship between the thermal runaway related parameter is the second corresponding relationship between the ratio of the changing temperature to the changing power and the battery power. The second corresponding relationship can be determined in the following manner.

[0080] (4) Determine the change in power of the battery based on the maximum capacity of the battery.

[0081] (5) Under the target working mode, when the battery changes its charge or discharge capacity each time, the temperature change of the battery under the change of charge is collected.

[0082] (6) Determine a second corresponding relationship based on the ratio of the changing temperature to the changing power and the battery power.

[0083] If the target operating mode is any of constant current charging, constant power charging, or pulse charging, each time the battery is charged to dQ of charge, the battery temperature before charging is subtracted from the battery temperature after charging to obtain the change in temperature dT. The battery is charged until the charge cutoff voltage, and n dTs can be obtained. After that, each dT is divided by dQ to obtain n dT / dQ values. That is, the dT / dQ values ​​are obtained for the periods when the charge changes from 0 to dQ, dQ to 2dQ, ..., (n-1)dQ to ndQ. Finally, a second corresponding relationship between the ratio of the change in temperature to the change in charge and the battery charge is obtained through interpolation.

[0084] Similarly, if the target operating mode is constant current discharge or constant power discharge mode, a second corresponding relationship between the ratio of the changing temperature to the changing power and the battery power can also be obtained by referring to the above method.

[0085] In this embodiment, when monitoring the thermal runaway of the battery, when the battery is charging or discharging, the battery power Q is first obtained through the battery monitoring system. i and temperature T i Then, the battery is charged or discharged for a certain amount of electricity dQ to obtain the temperature T after charging or discharging a certain amount of electricity dQ. i+1 , then, the temperature T i+1 Subtract temperature T i Get the current change in power (from Q i Change to Q i ±dQ) and compare the temperature change parameter dT with the current change in charge (from Q i Change to Q i ±dQ) is determined as the second parameter.

[0086] Finally, the power Q is determined from the pre-stored second corresponding relationship. i Change to Q i The dT / dQ value at ±dQ is determined as a parameter threshold corresponding to the second parameter. When the difference between the second parameter and the parameter threshold exceeds a preset range, it is determined that the battery has a thermal runaway risk.

[0087] In another embodiment, the current thermal runaway related parameter is a third parameter dT / dv, and the corresponding relationship of the thermal runaway related parameter is a third corresponding relationship between the ratio of the changing temperature to the second changing voltage and the battery voltage; the third corresponding relationship is determined in the following manner.

[0088] (7) Determine the second changed voltage of the battery based on the charge cut-off voltage and the discharge cut-off voltage of the battery.

[0089] For example, assuming that the charge cut-off voltage of the battery is Vch and the discharge cut-off voltage is Vdch, the second change voltage dv of the battery is = (Vch-Vdch) / n, where n is generally 100.

[0090] (8) Under the target working mode, each time the battery is charged or discharged to a second changing voltage, the changing temperature of the battery under the changing voltage is collected.

[0091] (9) A third corresponding relationship is determined according to the ratio of the changed temperature to the second changed voltage and the battery voltage.

[0092] If the target operating mode is any of constant current charging, constant power charging, or pulse charging, each time the battery voltage increases by the second variable voltage dv, the battery temperature before the voltage increase is subtracted from the battery temperature after the voltage increase to obtain the variable temperature dT. The battery is charged until the charge cutoff voltage is reached, resulting in n dT values. Each dT is then divided by dv to obtain n dT / dv values. This means that the dT / dv values ​​for the voltage changes from Vdch to Vdch+dv, Vdch+dv to Vdch+2dv, ..., and Vdch+(n-1)dv to Vch are obtained. Finally, a third corresponding relationship between the ratio of the variable temperature to the second variable voltage and the battery voltage is obtained through interpolation.

[0093] Similarly, if the target operating mode is constant current discharge or constant power discharge mode, a third corresponding relationship between the ratio of the changing temperature to the second changing voltage and the battery voltage can also be obtained by referring to the above method.

[0094] In this embodiment, when monitoring the thermal runaway of the battery, when the battery is charging or discharging, the battery voltage V is first obtained by the battery monitoring system. i and temperature T i Then, charge or discharge the battery to make the voltage change dv, and obtain the temperature T after the voltage change dv i+1 , then, the temperature T i+1 Subtract temperature T i Get the current change voltage (from V i Change to V i ±dv) and compare the temperature change parameter dT with the current change voltage (from Vi Change to V i The ratio of ±dv) is determined as the third parameter.

[0095] Finally, the voltage V is determined from the pre-stored third corresponding relationship. i Change to V i The dT / dv value at ±dv is determined as the parameter threshold corresponding to the third parameter. When the difference between the third parameter and the parameter threshold exceeds a preset range, it is determined that the battery has a thermal runaway risk.

[0096] It is worth noting that after obtaining the first corresponding relationship, or the second corresponding relationship, or the third corresponding relationship in the target working mode in the above manner, the above corresponding relationship can be stored in a battery monitoring system such as a production line formation equipment, a capacity control device, an MES (Manufacturing Execution System), a BMS (Battery Management System) or a cloud control platform for backup.

[0097] In addition, after the thermal runaway related parameter correspondence is determined in the above manner, in order to ensure the accuracy of the thermal runaway related parameter correspondence, the thermal runaway related parameter correspondence may be updated after a period of time.

[0098] The process of updating the thermal runaway-related parameter correspondence is as follows: in response to receiving an update request for the thermal runaway-related parameter correspondence, obtaining a target thermal runaway-related parameter correspondence, and then determining the target thermal runaway-related parameter correspondence as the preset thermal runaway-related parameter correspondence. In this way, the thermal runaway-related parameter correspondence can be updated.

[0099] It is worth noting that the battery sudden thermal runaway monitoring method provided in the present application can be used to monitor batteries in the use stage, and can also be used to monitor batteries in the production stage. When monitoring batteries in the production stage, the corresponding relationship of thermal runaway-related parameters determined based on batteries in the same batch that have been completed and have normal performance is updated. When monitoring batteries in the use stage, the corresponding relationship of thermal runaway-related parameters determined based on the historical charging or discharging process of the battery is updated. Therefore, when updating the corresponding relationship of thermal runaway-related parameters, the update method for batteries in the production stage and batteries in the use stage is not exactly the same.

[0100] For example, for batteries in the production stage, if raw material batches change or the battery production process is fine-tuned during the battery production process, the corresponding relationship between the battery's thermal runaway-related parameters will change. If the original corresponding relationship between the thermal runaway-related parameters is still used for thermal runaway monitoring, it will lead to misjudgment and poor accuracy in warning of sudden thermal runaway of the battery. Therefore, after raw material batch changes, battery production process fine-tuning, or production equipment aging, the corresponding relationship between the battery's thermal runaway-related parameters needs to be updated. For example, when raw material batches change, battery production process fine-tuning, or production equipment aging, a technician can send an update request to the device executing the battery sudden thermal runaway monitoring method to request an update of the corresponding relationship between the thermal runaway-related parameters. After receiving the update request sent by the technician, the device executing the battery sudden thermal runaway monitoring method controls the charging or discharging of other batteries that have been produced and are performing normally under different operating modes to obtain the target corresponding relationship between the thermal runaway-related parameters under different operating modes, and use this to update the corresponding relationship between the thermal runaway-related parameters. The other batteries refer to batteries from the same batch as the batteries in the production stage.

[0101] For batteries in use, the corresponding relationships of the battery's thermal runaway-related parameters will change during use due to factors such as battery aging and temperature. If the original corresponding relationships of the thermal runaway-related parameters are still used for thermal runaway monitoring, it will lead to misjudgment and poor accuracy in warning of sudden thermal runaway of the battery. Therefore, after the battery has been used for a period of time, or after the battery has experienced a certain degree of attenuation, an update request can be automatically generated and sent to the device executing the battery sudden thermal runaway monitoring method. After receiving the update request, the device executing the battery sudden thermal runaway monitoring method determines the corresponding relationship of the thermal runaway-related parameters determined during the battery's historical charging or discharging process as the target corresponding relationship of the thermal runaway-related parameters, and uses this to update the corresponding relationship of the thermal runaway-related parameters.

[0102] It's worth noting that, since batteries typically don't charge from zero to full each time during actual use (or discharge from full to zero), the actual charge / discharge voltage range or SOC range is random. Therefore, in practical applications, historical charge / discharge data from different times is used to update the thermal runaway-related parameter mapping relationships. For example, the battery monitoring system identifies a charge / discharge data set with a longer charging time and closer to the current time between the current moment and the last time the thermal runaway-related parameter mapping relationship was updated. This actual thermal runaway-related parameter mapping relationship is used to replace the thermal runaway-related parameter mapping relationship for the same charge or voltage range in the original thermal runaway-related parameter mapping relationship. By using multiple historical charge / discharge data sets, the thermal runaway-related parameter mapping relationship for the entire battery charge or voltage range is updated. Furthermore, because the high-voltage range of a battery has higher energy and greater internal expansion forces, it is more likely to cause sudden thermal runaway. Therefore, when updating the thermal runaway-related parameter mapping relationship, the thermal runaway-related parameter mapping relationship for the high voltage or high-capacity range is prioritized.

[0103] In this way, by updating the correspondence between the thermal runaway-related parameters, the accuracy of the correspondence between the thermal runaway-related parameters used when monitoring sudden thermal runaway of the battery can be ensured, thereby improving the accuracy of monitoring sudden thermal runaway of the battery.

[0104] FIG2 is a flow chart of another method for monitoring sudden thermal runaway of a battery according to an exemplary embodiment. As shown in FIG2 , in addition to steps 101 and 102 described above, the method may further include step 104 .

[0105] In step 104 , it is determined whether the current voltage of the battery is within a preset voltage range.

[0106] For example, the preset voltage range is a preset high voltage range, wherein the high voltage range can be set according to actual needs, and this application does not make any specific limitation on this.

[0107] Correspondingly, step 103 in FIG1 may further include step 1031 .

[0108] In step 1031, if it is within the preset voltage range, the battery is monitored for thermal runaway risk based on the current thermal runaway related parameters obtained this time, the thermal runaway related parameters obtained last time, and the relationship between the parameter thresholds.

[0109] In one possible approach, if the current voltage of the battery is within a preset voltage range, that is, the current voltage is considered to be within a high voltage area, and when the difference between the current thermal runaway-related parameter obtained this time and the parameter threshold exceeds a preset range, or when the difference between the current thermal runaway-related parameter obtained this time and the thermal runaway-related parameter obtained last time exceeds a certain range, it is determined that the battery is at risk of thermal runaway.

[0110] In another possible embodiment, if the current voltage of the battery is within a preset voltage range, that is, the current voltage is considered to be within a high voltage area, when the difference between the current thermal runaway related parameter obtained this time and the parameter threshold exceeds the preset range, and when the difference between the current thermal runaway related parameter obtained this time and the thermal runaway related parameter obtained last time exceeds a certain range, it is determined that the battery is at risk of thermal runaway.

[0111] In this way, when the current voltage of the battery is within the preset voltage range, thermal runaway is fully monitored through multiple features, so that the missed alarm rate of thermal runaway is low.

[0112] After determining that the battery has a thermal runaway risk according to the method shown in Figure 1 or Figure 2, corresponding actions can also be triggered to provide early warning or protection against thermal runaway of the battery.

[0113] For example, in one possible approach, if a battery is determined to be at risk of thermal runaway, a prompt message is output to prompt the user to stop charging or discharging, and / or a thermal runaway warning signal is output to alert the user that the battery is at risk of thermal runaway. The prompt message may be a voice prompt or a text prompt, which is not specifically limited in this application. Similarly, the thermal runaway warning signal may be an alarm signal emitted by an alarm device, which may be an acoustic alarm signal and / or a light alarm signal, which is also not specifically limited in this application.

[0114] In another possible approach, when it is determined that the battery is at risk of thermal runaway, a cooling or firefighting action may be directly triggered to cool the battery, or the safety of equipment around the battery may be ensured by triggering a firefighting action.

[0115] In another possible embodiment, when it is determined that the battery is at risk of thermal runaway, a prompt message is output to instruct to stop charging or discharging, and / or a thermal runaway warning signal is output, and at the same time, a cooling or fire-fighting action is triggered.

[0116] The above technical solution can output prompt information and / or warning signals when a battery is determined to be at risk of thermal runaway, allowing users to be notified of the risk in advance and take effective measures to ensure battery safety. Furthermore, when the risk of thermal runaway is determined, cooling or firefighting actions can be automatically triggered, increasing the flexibility and intelligence of the battery's sudden thermal runaway monitoring method.

[0117] Based on the same inventive concept, this application also provides a battery sudden thermal runaway monitoring device. FIG3 is a block diagram of a battery sudden thermal runaway monitoring device according to an exemplary embodiment. As shown in FIG3 , the battery sudden thermal runaway monitoring device 300 may include:

[0118] a first acquisition module 301, configured to acquire current thermal runaway-related parameters of the battery in a target operating mode, the current thermal runaway-related parameters including at least one of a first parameter for characterizing a voltage variation parameter under a current change in power, a second parameter for characterizing a temperature variation parameter under a current change in power, and a third parameter for characterizing a temperature variation parameter under a current change in voltage;

[0119] A second acquisition module 302 is configured to acquire a parameter threshold corresponding to the current thermal runaway related parameter from a preset thermal runaway related parameter correspondence relationship under the target operating mode;

[0120] The monitoring module 303 is configured to monitor whether the battery has a thermal runaway risk based on the current thermal runaway related parameters and the parameter thresholds.

[0121] Optionally, the device may further include:

[0122] A first determining module, configured to determine whether the current voltage of the battery is within a preset voltage range;

[0123] The monitoring module 303 is used to: if it is within the preset voltage range, monitor whether the battery has a thermal runaway risk based on the current thermal runaway related parameters obtained this time, the thermal runaway related parameters obtained last time, and the relationship between the parameter thresholds.

[0124] Optionally, the current thermal runaway related parameter is the first parameter, and the corresponding relationship of the thermal runaway related parameter is a first corresponding relationship between a ratio of a changing voltage to a changing power and the battery power; the first corresponding relationship is determined by:

[0125] determining a change in the amount of electricity of the battery according to the maximum capacity of the battery;

[0126] In the target operating mode, each time the battery charges or discharges the variable electrical quantity, a first variable voltage generated by the battery under the variable electrical quantity is collected;

[0127] The first corresponding relationship is determined according to a ratio of the first changed voltage to the changed power and the battery power.

[0128] Optionally, the current thermal runaway related parameter is the second parameter, and the thermal runaway related parameter correspondence is a second correspondence between a ratio of a changing temperature to a changing power and the battery power; the second correspondence is determined by:

[0129] determining a change in the amount of electricity of the battery according to the maximum capacity of the battery;

[0130] In the target operating mode, each time the battery charges or discharges the variable amount of electricity, a temperature change generated by the battery under the variable amount of electricity is collected;

[0131] The second corresponding relationship is determined according to the ratio of the changed temperature to the changed power and the battery power.

[0132] Optionally, the current thermal runaway related parameter is the third parameter, and the corresponding relationship of the thermal runaway related parameter is a third corresponding relationship between a ratio of the changing temperature to the second changing voltage and the battery voltage; the third corresponding relationship is determined by:

[0133] determining a second changed voltage of the battery according to a charge cut-off voltage and a discharge cut-off voltage of the battery;

[0134] In the target operating mode, each time the battery charges or discharges the second variable voltage, a temperature change generated by the battery under the variable power is collected;

[0135] The third corresponding relationship is determined according to the ratio of the changed temperature to the second changed voltage and the battery voltage.

[0136] Optionally, the device may further include:

[0137] a third acquisition module, configured to acquire a target thermal runaway related parameter correspondence relationship in response to receiving an update request for the thermal runaway related parameter correspondence relationship;

[0138] A second determining module, configured to determine the target thermal runaway related parameter correspondence as a preset thermal runaway related parameter correspondence;

[0139] Wherein, when the battery is in the production stage, the target thermal runaway related parameter correspondence relationship is a thermal runaway related parameter correspondence relationship determined based on other batteries that have been produced and have normal performance;

[0140] When the battery is in use, the target thermal runaway-related parameter correspondence is a thermal runaway-related parameter correspondence determined according to a historical charging or discharging process of the battery.

[0141] Optionally, the monitoring module 303 is configured to determine that the battery has a thermal runaway risk if the difference between the current thermal runaway related parameter and the parameter threshold exceeds a preset range.

[0142] Optionally, the device may further include:

[0143] an output module, configured to output a prompt message for instructing to stop charging or discharging, and / or output a thermal runaway warning signal, when it is determined that the battery has a risk of thermal runaway; and / or

[0144] The trigger module is used to trigger a cooling or fire-fighting action when it is determined that the battery has a risk of thermal runaway.

[0145] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0146] FIG4 is a block diagram of an electronic device according to an exemplary embodiment. As shown in FIG4 , the electronic device 700 may include a processor 701 and a memory 702. The electronic device 700 may also include one or more of a multimedia component 703, an input / output (I / O) interface 704, and a communication component 705.

[0147] The processor 701 is used to control the overall operation of the electronic device 700 to complete all or part of the steps in the above-mentioned battery sudden thermal runaway monitoring method. The memory 702 is used to store various types of data to support the operation of the electronic device 700. For example, this data may include instructions for any application or method operating on the electronic device 700, as well as application-related data, such as contact information, sent and received messages, pictures, audio, video, etc. The memory 702 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 703 may include a screen and an audio component. The screen may be, for example, a touch screen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signals may be stored in the memory 702 or transmitted via the communication component 705. The audio component also includes at least one speaker for outputting audio signals. The I / O interface 704 provides an interface between the processor 701 and other interface modules. The aforementioned other interface modules may be a keyboard, a mouse, buttons, etc. These buttons may be virtual buttons or physical buttons. The communication component 705 is used for wired or wireless communication between the electronic device 700 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IOT, eMTC, or other 5G, etc., or a combination of one or more thereof, is not limited here. Therefore, the corresponding communication component 705 may include: a Wi-Fi module, a Bluetooth module, an NFC module, etc.

[0148] In an exemplary embodiment, the electronic device 700 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the above-mentioned battery sudden thermal runaway monitoring method.

[0149] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided. When executed by a processor, the program instructions implement the steps of the above-described method for monitoring sudden battery thermal runaway. For example, the computer-readable storage medium may be the aforementioned memory 702 including the program instructions. The program instructions may be executed by the processor 701 of the electronic device 700 to implement the above-described method for monitoring sudden battery thermal runaway.

[0150] In another exemplary embodiment, a computer program product is provided. The computer program product includes a computer program executable by a programmable device, and the computer program has a code portion for executing the above-mentioned battery sudden thermal runaway monitoring method when executed by the programmable device.

[0151] The above describes in detail the optional implementation methods of the present application in conjunction with the accompanying drawings. However, the present application is not limited to the specific details of the above implementation methods. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the scope of protection of the present application.

[0152] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this application will not further describe various possible combinations.

[0153] In addition, the various implementation methods of the present application can be arbitrarily combined, as long as they do not violate the concept of the present application, they should also be regarded as the content of the present application.

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