Battery thermal runaway early warning method, device and equipment and vehicle

Abstract

The invention provides a battery thermal runaway early warning method, device and equipment and a vehicle, relates to the technical field of vehicles, can effectively carry out early warning on sudden thermal runaway and improve the reliability and safety of a battery, and comprises the following steps: obtaining an instantaneous drop voltage difference of each single battery in a battery pack of the vehicle, the instantaneous drop voltage difference of the single battery is used for reflecting the difference value between the voltage value of the single battery at the current moment and the voltage value of the single battery at the previous moment; determining whether the battery pack of the vehicle has a thermal runaway risk or not according to the instantaneous drop voltage difference of each single battery; and under the condition of determining that the battery pack of the vehicle has the thermal runaway risk, performing thermal runaway early warning.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a battery thermal runaway warning method, device, equipment and vehicle. Background Art

[0002] In recent years, new energy vehicles, as a highly energy-efficient alternative to fuel vehicles, have seen tenfold growth in the past decade. With the rapid increase in the number of new energy vehicles, battery safety issues have become prominent, and thermal runaway incidents have occurred, making vehicle safety monitoring urgent. Currently, vehicle-side data is uploaded to the cloud. Leveraging the cloud's powerful data and computing capabilities, early warning algorithms developed based on battery temperature, current, voltage, and other signals are becoming increasingly mature, capable of timely warning and processing most abnormal signals, reducing the probability of battery thermal runaway. However, cloud-based data focuses on analyzing long-term battery data trends, and can easily overlook sudden thermal runaway caused by sudden internal short circuits. This type of thermal runaway has long-term characteristics without abnormalities, making it difficult for conventional algorithms to identify. As a result, a small number of new energy vehicles still experience smoke, fire, and even explosions.

[0003] In related technologies, the level of thermal runaway in power batteries is determined by measuring battery voltage, battery temperature, and battery expansion force, which in turn generates an alarm signal. While this method ensures immediacy and accuracy in monitoring the battery expansion force, it requires the use of a specific pressure sensor, which increases the complexity of the battery pack and therefore has certain limitations in terms of cost and feasibility. Another related technology determines whether to issue a thermal runaway warning based on the difference between the battery's current voltage and the battery's voltage at the previous moment. However, this method considers the voltage difference of the entire battery pack. While it can provide a warning for battery thermal runaway, it cannot meet the requirements for timeliness and accuracy. In summary, related technologies cannot provide timely and effective warnings for sudden thermal runaway of batteries. Summary of the Invention

[0004] The present application provides a battery thermal runaway warning method, device, equipment and vehicle, aiming to timely and effectively warn of sudden thermal runaway of the battery and improve the reliability and safety of the battery.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present application provides a battery thermal runaway warning method, which includes: obtaining the instantaneous voltage drop difference of each single cell in a vehicle's battery pack, where the instantaneous voltage drop difference of the single cell is used to reflect the difference between the voltage value of the single cell at a current moment and the voltage value of the single cell at a previous moment; determining whether the vehicle's battery pack has a thermal runaway risk based on the instantaneous voltage drop difference of each single cell; and performing a thermal runaway warning when it is determined that the vehicle's battery pack has a thermal runaway risk.

[0007] Based on the above technical means, the present application can monitor the voltage of each single cell in the battery pack at the current moment and the voltage at the adjacent previous moment, determine the instantaneous voltage drop difference of each single cell, and based on the instantaneous voltage drop difference of each single cell, determine whether the battery pack is at risk of thermal runaway, and then perform a thermal runaway warning. By monitoring each single cell and then promptly locating the single cell that has experienced thermal runaway, the present application can accurately and effectively warn whether the battery pack will experience thermal runaway, thereby improving the accuracy of identification; at the same time, the solution does not require the addition of additional devices, thus controlling the cost of vehicle manufacturing. In summary, the present application can timely and effectively warn of sudden thermal runaway of the battery, thereby improving the reliability and safety of the battery.

[0008] One possible implementation method is to determine whether a vehicle's battery pack has a risk of thermal runaway based on the instantaneous voltage drop difference of each single cell, including: for a first single cell in the battery pack, if the instantaneous voltage drop difference of the first single cell is greater than or equal to a first thermal runaway warning value, and the instantaneous voltage drop differences of other single cells in the battery pack except the first single cell are all less than a second thermal runaway warning value, determining that the vehicle's battery pack has a risk of thermal runaway; wherein the first single cell is any single cell in the battery pack.

[0009] Based on the above technical means, when monitoring the battery pack, if the instantaneous voltage drop difference of a single cell is greater than or equal to the first thermal runaway warning value, and the instantaneous voltage drop difference of the remaining cells is less than the second thermal runaway warning value, the vehicle's battery pack is determined to be at risk of thermal runaway. This allows the precise location of cells at risk of thermal runaway and cells that may be affected in the future, providing an effective basis for subsequent warnings.

[0010] Another possible implementation method is to determine whether the vehicle's battery pack has a risk of thermal runaway based on the instantaneous voltage drop difference of each single cell. The method also includes: determining the thermal runaway warning value corresponding to the vehicle's battery pack based on the correspondence between the vehicle's battery pack type and preset parameters; the preset parameter correspondence is used to reflect the thermal runaway warning values corresponding to different types of battery packs.

[0011] It is understood that since different vehicle models may have the same or different battery pack types, different battery pack types may have different corresponding thermal runaway warning values. Therefore, this application can determine the corresponding thermal runaway warning value for a vehicle's battery pack based on the vehicle's battery pack type and parameter mapping. This parameter mapping includes the corresponding thermal runaway warning values for different battery pack types, which can provide a thermal runaway warning reference value when monitoring the risk of thermal runaway in a battery pack.

[0012] Another possible implementation method is to determine the thermal runaway warning value corresponding to the vehicle's battery pack based on the correspondence between the vehicle's battery pack type and preset parameters. The method also includes: conducting thermal runaway experiments based on multiple different types of sample battery packs to construct a preset parameter correspondence.

[0013] It can be understood that in order to make the setting of the thermal runaway warning value in the parameter correspondence scientific and rigorous, this application conducts thermal runaway experiments based on a variety of different types of sample battery packs, and constructs preset parameter correspondences based on the experiments, so as to obtain accurate thermal runaway warning values corresponding to different types of battery packs.

[0014] Another possible implementation method is to conduct thermal runaway experiments based on multiple different types of sample battery packs and construct a preset parameter correspondence, including: for each type of sample battery pack in the multiple different types of sample battery packs, triggering thermal runaway of a second single cell in the sample battery pack; wherein the second single cell is any one in the sample battery pack; when thermal runaway occurs in the second single cell, obtaining the instantaneous voltage drop difference of the second single cell and the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell; based on the instantaneous voltage drop difference of the second single cell, determining a first thermal runaway warning value corresponding to the sample battery pack; based on the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell, determining a second thermal runaway warning value corresponding to the sample battery pack; constructing a preset parameter correspondence based on the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of sample battery pack.

[0015] It is understandable that in order to ensure that the setting of thermal runaway warning values in the parameter mapping is scientific and rigorous, this application conducts thermal runaway experiments based on various types of sample battery packs and establishes preset parameter mappings based on these experiments. For example, when thermal runaway is triggered in a single cell of a sample battery pack, the first thermal runaway warning value corresponding to the sample battery pack is determined based on the instantaneous voltage drop of the single cell; the second thermal runaway warning value corresponding to the sample battery pack is determined based on the instantaneous voltage drop of the single cells in the sample battery pack except the second single cell. In this way, the thermal runaway warning values corresponding to different types of battery packs can be accurately determined.

[0016] Another possible implementation method is that there are multiple second single cells, and the triggering moments of the multiple second single cells are different, and the triggering moment is the moment when the second single cell experiences thermal runaway; based on the instantaneous drop voltage difference of the second single cell, the first thermal runaway warning value corresponding to the sample battery pack is determined, including: based on the average value of the instantaneous drop voltage difference of the multiple second single cells, the first thermal runaway warning value corresponding to the sample battery pack is determined.

[0017] It is understood that a thermal runaway test can include multiple runs, with each runaway test triggering thermal runaway in a second cell to obtain a transient voltage drop across the second cell. Based on this, the present application can determine the first thermal runaway warning value for the sample battery pack based on the average of the transient voltage drops across multiple second cells obtained from the multiple runs. This allows for accurate determination of the thermal runaway warning value.

[0018] Another possible implementation method is to determine the second thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell, including: determining the second thermal runaway warning value corresponding to the sample battery pack based on the three times standard deviation criterion and the average value of the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell.

[0019] Based on the above technical means and the triple standard deviation principle, the present application can determine the second thermal runaway warning value corresponding to the sample battery pack based on the average of the transient voltage drop differences of multiple single cells other than the second single cell. Because the triple standard deviation principle can effectively reflect the characteristics of the data, the second thermal runaway warning value obtained using the triple standard deviation principle is more accurate and scientific.

[0020] Another possible implementation method is to obtain the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle, including: when the vehicle is in a preset operating condition, obtaining the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle; wherein the preset operating condition includes one of the following: stationary operating condition, driving operating condition.

[0021] Based on the above technical means, the present application can monitor the instantaneous voltage drop difference of the single cells of the battery pack under stationary or driving conditions, so as to detect the risk of thermal runaway of the battery pack under different discharge conditions, realize thermal runaway warning of the battery pack under different discharge conditions, and improve the safety of the vehicle during parking and driving.

[0022] In a second aspect, the present application provides a battery thermal runaway warning device, comprising: an acquisition module, a determination module, and a warning module. The acquisition module is used to obtain the instantaneous voltage drop difference of each single cell in a vehicle's battery pack, where the instantaneous voltage drop difference of each single cell reflects the difference between the voltage value of the single cell at the current moment and the voltage value of the single cell at the previous moment. The determination module is used to determine whether the vehicle's battery pack is at risk of thermal runaway based on the instantaneous voltage drop difference of each single cell. The warning module is used to issue a thermal runaway warning if it is determined that the vehicle's battery pack is at risk of thermal runaway.

[0023] In one possible implementation, the determination module is specifically used to: for a first single cell in a battery pack, when the instantaneous voltage drop difference of the first single cell is greater than or equal to a first thermal runaway warning value, and the instantaneous voltage drop differences of other single cells in the battery pack except the first single cell are all less than a second thermal runaway warning value, determine that the vehicle's battery pack is at risk of thermal runaway; wherein the first single cell is any single cell in the battery pack.

[0024] In another possible implementation, the determination module is further used to: determine the thermal runaway warning value corresponding to the vehicle's battery pack based on the correspondence between the vehicle's battery pack type and preset parameters; the preset parameter correspondence is used to reflect the thermal runaway warning values corresponding to different types of battery packs.

[0025] In another possible implementation, the determination module is further used to: conduct thermal runaway experiments based on a variety of different types of sample battery packs to establish a corresponding relationship between preset parameters.

[0026] In another possible implementation, the determination module is specifically used to: trigger thermal runaway of a second single cell in a sample battery pack of each type among a plurality of different types of sample battery packs; wherein the second single cell is any one in the sample battery pack; when thermal runaway occurs in the second single cell, obtain the instantaneous drop voltage difference of the second single cell, and the instantaneous drop voltage difference of other single cells in the sample battery pack except the second single cell; determine a first thermal runaway warning value corresponding to the sample battery pack based on the instantaneous drop voltage difference of the second single cell; determine a second thermal runaway warning value corresponding to the sample battery pack based on the instantaneous drop voltage difference of other single cells in the sample battery pack except the second single cell; and construct a preset parameter correspondence relationship based on the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of sample battery pack.

[0027] In another possible implementation, there are multiple second single cells, and the triggering moments of the multiple second single cells are different, and the triggering moment is the moment when the thermal runaway of the second single cell occurs; the determination module is specifically used to: determine the first thermal runaway warning value corresponding to the sample battery pack based on the average value of the instantaneous voltage drop difference of the multiple second single cells.

[0028] In another possible implementation, the determination module is specifically used to determine the second thermal runaway warning value corresponding to the sample battery pack based on the three standard deviation criterion and the average value of the instantaneous drop voltage difference of the other single cells in the sample battery pack except the second single cell.

[0029] In another possible implementation, the acquisition module is specifically used to: obtain the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle when the vehicle is in a preset operating condition; wherein the preset operating condition includes one of the following: a stationary operating condition and a driving operating condition.

[0030] In a third aspect, the present application provides an electronic device comprising: a processor and a memory; the memory stores instructions executable by the processor; when the processor is configured to execute the instructions, the electronic device implements the method of the first aspect above.

[0031] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon, which implement the method of the first aspect when executed by a processor.

[0032] In a fifth aspect, an embodiment of the present application provides a computer program product, which includes computer program instructions, and when the computer program instructions are executed by a processor, the method of the first aspect is implemented.

[0033] In a sixth aspect, an embodiment of the present application provides a vehicle, which includes the electronic device provided in the fourth aspect above.

[0034] It should be noted that the technical effects brought about by any implementation method in the second to sixth aspects can refer to the technical effects brought about by the corresponding implementation method in the first aspect, and will not be repeated here.

[0035] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flow chart of a battery thermal runaway early warning method provided in this application;

[0037] Figure 2 A flow chart of another battery thermal runaway warning method provided in this application;

[0038] Figure 3 A flowchart of another battery thermal runaway warning method provided in this application;

[0039] Figure 4 A flowchart of another battery thermal runaway warning method provided in this application;

[0040] Figure 5 A schematic diagram of a thermal runaway monitoring alarm provided in this application;

[0041] Figure 6 A schematic diagram of the composition of a battery thermal runaway warning device provided in this application;

[0042] Figure 7 A schematic diagram of the composition of an electronic device provided in this application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0044] It should be noted that in the embodiments of this application, words such as "exemplarily" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described in the embodiments of this application as "exemplarily" or "for example" should not be interpreted as being more preferred or advantageous than other embodiments or designs. Rather, the use of words such as "exemplarily" or "for example" is intended to present the relevant concepts in a concrete manner.

[0045] In order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish between identical or similar items with basically the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order.

[0046] As a possible implementation, the battery thermal runaway warning method provided in the embodiments of the present application can be executed by an electronic device that can communicate with the vehicle to obtain vehicle operating data and battery pack operating data. For example, the battery pack operating data includes charge status, total current, and cell voltage.

[0047] For example, the electronic device may be a server, for example, a single server, or a server cluster composed of multiple servers. In some implementations, the server cluster may also be a distributed cluster.

[0048] For example, the electronic device may be a terminal device, such as a mobile phone, a tablet computer, a desktop computer, a laptop computer, a handheld computer, a notebook computer, an ultra-mobile personal computer (UMPC), a netbook computer, a cellular phone, a personal digital assistant (PDA), an augmented reality (AR) or virtual reality (VR) device, etc. The embodiments of the present application do not impose any particular limitation on the specific form of the terminal device.

[0049] As another possible implementation, the battery thermal runaway warning method provided in the embodiment of the present application may be executed by a vehicle controller, such as a battery management system (BMS).

[0050] This application provides a battery thermal runaway early warning method, such as Figure 1 As shown, the process specifically includes the following steps S11 to S13:

[0051] S11. Obtain the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle.

[0052] The instantaneous voltage drop difference of the single cell is used to reflect the difference between the voltage value of the single cell at the current moment and the voltage value of the single cell at the previous moment.

[0053] In some embodiments, step S11 includes: when the vehicle is in a preset operating condition, obtaining the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle; wherein the preset operating condition includes one of the following: a stationary operating condition, a driving operating condition.

[0054] Based on the above technical means, the present application can monitor the instantaneous voltage drop difference of the single cells of the battery pack under stationary or driving conditions, so as to detect the risk of thermal runaway of the battery pack under different discharge conditions, realize thermal runaway warning of the battery pack under different discharge conditions, and improve the safety of the vehicle during parking and driving.

[0055] S12. Determine whether the vehicle's battery pack has a risk of thermal runaway based on the instantaneous voltage drop difference of each single battery cell.

[0056] In some embodiments, step S12 can be implemented as follows: for the first single cell in the battery pack, when the instantaneous voltage drop difference of the first single cell is greater than or equal to the first thermal runaway warning value, and the instantaneous voltage drop differences of other single cells in the battery pack except the first single cell are all less than the second thermal runaway warning value, it is determined that the vehicle's battery pack is at risk of thermal runaway.

[0057] The first single cell is any single cell in the battery pack.

[0058] Based on the above technical means, when monitoring the battery pack, if the instantaneous voltage drop difference of a single cell is greater than or equal to the first thermal runaway warning value, and the instantaneous voltage drop difference of the remaining cells is less than the second thermal runaway warning value, the vehicle's battery pack is determined to be at risk of thermal runaway. This allows the precise location of cells at risk of thermal runaway and cells that may be affected in the future, providing an effective basis for subsequent warnings.

[0059] S13. When it is determined that the vehicle's battery pack has a risk of thermal runaway, a thermal runaway warning is issued.

[0060] Based on the above technical means, this application extracts the voltage data during the battery discharge process, and considers the phenomenon that when a sudden short circuit occurs inside the battery cell (single battery), an instantaneous voltage drop will occur under a certain discharge current, while the voltage of other normal battery cells is normal. It is thereby determined that the battery cell with a sudden drop has a thermal runaway risk and a thermal runaway warning is issued, thereby improving the warning capability for sudden thermal runaway of the battery and reducing the occurrence of battery pack overheating during vehicle operation.

[0061] It is understandable that this application monitors the operating data of each single cell (such as cell voltage) and promptly locates the single cell experiencing thermal runaway, which can accurately and effectively warn whether the battery pack will experience thermal runaway, thereby improving the accuracy of identification. At the same time, this solution does not require the addition of additional devices, thus controlling the cost of vehicle manufacturing. In summary, this application can provide timely and effective warnings for sudden thermal runaway of batteries, thereby improving the reliability and safety of batteries.

[0062] In some embodiments, before step S12, the method further includes: determining a thermal runaway warning value corresponding to the battery pack of the vehicle based on a correspondence between the battery pack type of the vehicle and preset parameters.

[0063] Among them, the preset parameter correspondence is used to reflect the thermal runaway warning values corresponding to different types of battery packs.

[0064] Exemplarily, the vehicle model is obtained, and the configured battery pack type is determined based on the vehicle model, and then the thermal runaway warning value corresponding to the vehicle battery pack is queried according to the battery pack type in the preset parameter correspondence.

[0065] It is understood that since different vehicle models may have the same or different battery pack types, different battery pack types may have different corresponding thermal runaway warning values. Therefore, this application can determine the corresponding thermal runaway warning value for a vehicle's battery pack based on the vehicle's battery pack type and parameter mapping. This parameter mapping includes the corresponding thermal runaway warning values for different battery pack types, which can provide a thermal runaway warning reference value when monitoring the risk of thermal runaway in a battery pack.

[0066] In some embodiments, the above method further includes: conducting thermal runaway experiments based on a plurality of different types of sample battery packs to construct a preset parameter correspondence relationship.

[0067] It can be understood that in order to make the setting of the thermal runaway warning value in the parameter correspondence scientific and rigorous, this application conducts thermal runaway experiments based on a variety of different types of sample battery packs, and constructs preset parameter correspondences based on the experiments, so as to obtain accurate thermal runaway warning values corresponding to different types of battery packs.

[0068] In some embodiments, such as Figure 2 As shown, the above-mentioned "constructing a preset parameter correspondence relationship based on thermal runaway experiments of various types of sample battery packs" can be implemented as steps S21 to S25:

[0069] S21 . For each type of sample battery pack among a plurality of different types of sample battery packs, trigger thermal runaway of a second single battery cell in the sample battery pack.

[0070] The second single battery is any one of the sample battery packs.

[0071] Illustratively, there may be one or more second unit batteries.

[0072] Exemplarily, the second single cell is a marked target cell.

[0073] For example, thermal runaway of the second single cell in the sample battery pack is triggered by a method such as needle puncture.

[0074] S22 . When thermal runaway occurs in the second single cell, obtain the instantaneous voltage drop difference of the second single cell and the instantaneous voltage drop differences of other single cells in the sample battery pack except the second single cell.

[0075] S23 : Determine a first thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of the second single battery cell.

[0076] In some embodiments, there is one second single battery cell, and step S23 can be implemented as: using the instantaneous voltage drop difference of the second single battery cell as the first thermal runaway warning value corresponding to the sample battery pack.

[0077] In some embodiments, there are multiple second single cells, and the triggering moments of the multiple second single cells are different, and the triggering moment is the moment when the second single cell experiences thermal runaway. Then, step S23 can be implemented as follows: based on the average value of the instantaneous voltage drop difference of the multiple second single cells, determine the first thermal runaway warning value corresponding to the sample battery pack.

[0078] It is understood that a thermal runaway test can include multiple runs, with each runaway test triggering thermal runaway in a second cell to obtain a transient voltage drop across the second cell. Based on this, the present application can determine the first thermal runaway warning value for the sample battery pack based on the average of the transient voltage drops across multiple second cells obtained from the multiple runs. This allows for accurate determination of the thermal runaway warning value.

[0079] S24 . Determine a second thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of the other single cells except the second single cell in the sample battery pack.

[0080] In some embodiments, step S24 may be implemented as follows: determining a second thermal runaway warning value corresponding to the sample battery pack based on a three-times standard deviation criterion and an average value of transient voltage drops of cells other than the second cell in the sample battery pack.

[0081] Exemplarily, based on the triple standard deviation criterion, the average value μ of the instantaneous voltage drop difference of the other single cells in the battery pack except the second single cell and the standard deviation σ of the instantaneous voltage drop difference of the other single cells in the battery pack except the second single cell are calculated, and the value of 3σ+μ is used as the second thermal runaway warning value corresponding to the sample battery pack.

[0082] Based on the above technical means and the triple standard deviation principle, the present application can determine the second thermal runaway warning value corresponding to the sample battery pack based on the average of the transient voltage drop differences of multiple single cells other than the second single cell. Because the triple standard deviation principle can effectively reflect the characteristics of the data, the second thermal runaway warning value obtained using the triple standard deviation principle is more accurate and scientific.

[0083] Illustratively, when there are multiple second single battery cells, the average value of the second thermal runaway warning values corresponding to the multiple second single battery cells is used as the final second thermal runaway warning value of the sample battery pack.

[0084] S25. Construct a preset parameter correspondence based on the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of sample battery pack.

[0085] Exemplarily, the preset parameter correspondence includes each type of battery pack and the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of battery pack.

[0086] It can be understood that this application establishes the instantaneous voltage drop parameters at the moment of thermal runaway of different battery cells through thermal runaway experiments, and sets thresholds for different battery cells (first thermal runaway warning value and second thermal runaway warning value) in a targeted manner, which improves the accuracy of the warning model to a certain extent.

[0087] The following describes a specific embodiment of the battery thermal runaway warning method provided by this application. The battery thermal runaway warning method provided by this application includes two parts: one is about the construction of the corresponding relationship between preset parameters, and the other is the application of the battery thermal runaway warning method when the vehicle is stationary or running.

[0088] First, let’s take the construction of the preset parameter correspondence as an example. Figure 3 As shown, the following steps S31 to S34 are included:

[0089] S31. Conduct thermal runaway tests on different types of battery packs to obtain the instantaneous voltage drop difference between the target cell and the remaining cells when the cell experiences thermal runaway.

[0090] For example, a thermal runaway test is performed on a whole pack of 50Ah battery cells, where the series-parallel connection mode of the whole pack is 3P96S, with a total of 96 single cells.

[0091] S32. Taking the instantaneous voltage drop when the target cell experiences thermal runaway as a first preset threshold.

[0092] Exemplarily, the first preset threshold of the target cell is 0.1V.

[0093] S33: Setting a second preset threshold based on the instantaneous voltage drop difference of the single battery cells when the target battery cell is in thermal runaway.

[0094] Exemplarily, 3σ+μ is calculated to obtain the second preset threshold value as 0.0159V.

[0095] S34: Establish a corresponding relationship between preset parameters for thermal runaway of the battery pack, including first preset thresholds and second preset thresholds for battery packs with different types of cells.

[0096] For example, the first preset threshold value of the battery pack corresponding to a 50Ah battery cell is 0.1V, and the second preset threshold value is 0.0159V.

[0097] Secondly, the application of the battery thermal runaway warning method under vehicle stationary or running conditions is explained as an example. Figure 4 As shown, the following steps S41 to S47 are included:

[0098] S41. Query a first thermal runaway warning value and a second thermal runaway warning value corresponding to the vehicle battery pack according to a preset parameter correspondence relationship of the vehicle model.

[0099] S42: Collect vehicle data at the current moment and the previous moment.

[0100] S43: Process the collected vehicle data.

[0101] Exemplarily, processing the data includes: cleaning the data, and retaining the acquisition time, charging state, total current, and voltage value of each single cell.

[0102] S44. Extract the processed data to obtain the voltage of each single cell in the vehicle battery pack at the current moment and the voltage at the previous moment.

[0103] S45. Calculate the instantaneous voltage drop difference of each single cell in the vehicle battery pack.

[0104] S46 , determining whether there is a single cell whose instantaneous voltage drop difference is greater than or equal to the first thermal runaway warning value and whether there is a single cell whose instantaneous voltage drop difference is less than the second thermal runaway warning value.

[0105] If yes, execute step S47; if not, wait for the next moment and repeat steps S42 to S46.

[0106] S47. Issue a thermal runaway warning to the vehicle.

[0107] For example, at time t, the instantaneous voltage drop difference of the 42nd single cell is 0.154V, which is greater than the first preset threshold value of 0.1V, and the instantaneous voltage drop differences of the remaining single cells are all less than the second preset threshold value of 0.0159V. At this time, a thermal runaway warning is issued for the 42nd single cell; the thermal runaway monitoring alarm situation involved in this example is as follows Figure 5 shown.

[0108] The above mainly introduces the solution of the embodiment of the present disclosure from the perspective of method. It can be understood that, in order to realize the above functions, the preset parameter correspondence construction device or the battery thermal runaway warning device includes at least one of the hardware structure and software modules corresponding to the execution of each function. It should be easy for those skilled in the art to realize that, in combination with the units and algorithm steps of each example described in the embodiment disclosed herein, the embodiment of the present disclosure can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the embodiment of the present disclosure.

[0109] The embodiment of the present disclosure can divide the preset parameter correspondence construction device or the battery thermal runaway warning device into functional modules according to the above-mentioned method embodiment. For example, each functional module can be divided corresponding to each function, or two or more functions can be integrated into one functional module. The above-mentioned integrated module can be implemented in the form of hardware or software. It should be noted that the division of modules in the embodiment of the present disclosure is schematic and is only a logical function division. There may be other division methods in actual implementation. The following is an example of dividing each functional module corresponding to each function.

[0110] In some embodiments, the present application provides a possible structure of a battery thermal runaway warning device, such as Figure 6As shown, the battery thermal runaway warning device 600 includes an acquisition module 601, a determination module 602, and a warning module 603. The acquisition module 601 is used to obtain the instantaneous voltage drop difference of each single cell in the vehicle's battery pack. The instantaneous voltage drop difference of each single cell reflects the difference between the voltage value of the single cell at the current moment and the voltage value of the single cell at the previous moment. The determination module 602 is used to determine whether the vehicle's battery pack has a thermal runaway risk based on the instantaneous voltage drop difference of each single cell. The warning module 603 is used to issue a thermal runaway warning if it is determined that the vehicle's battery pack has a thermal runaway risk.

[0111] In one possible implementation, the determination module 602 is specifically used to: for a first single cell in a battery pack, when the instantaneous voltage drop difference of the first single cell is greater than or equal to a first thermal runaway warning value, and the instantaneous voltage drop differences of other single cells in the battery pack except the first single cell are all less than a second thermal runaway warning value, determine that the vehicle's battery pack has a thermal runaway risk; wherein the first single cell is any single cell in the battery pack.

[0112] In another possible implementation, the determination module 602 is further used to: determine the thermal runaway warning value corresponding to the vehicle's battery pack based on the correspondence between the vehicle's battery pack type and preset parameters; the preset parameter correspondence is used to reflect the thermal runaway warning values corresponding to different types of battery packs.

[0113] In another possible implementation, the determination module 602 is further configured to: conduct thermal runaway experiments based on a plurality of different types of sample battery packs to construct a corresponding relationship between preset parameters.

[0114] In another possible implementation, the determination module 602 is specifically used to: for each type of sample battery pack among multiple different types of sample battery packs, trigger thermal runaway of a second single cell in the sample battery pack; wherein the second single cell is any one in the sample battery pack; when thermal runaway occurs in the second single cell, obtain the instantaneous voltage drop difference of the second single cell, and the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell; based on the instantaneous voltage drop difference of the second single cell, determine the first thermal runaway warning value corresponding to the sample battery pack; based on the instantaneous voltage drop difference of other single cells in the sample battery pack except the second single cell, determine the second thermal runaway warning value corresponding to the sample battery pack; based on the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of sample battery pack, construct a preset parameter correspondence.

[0115] In another possible implementation, there are multiple second single cells, and the triggering moments of the multiple second single cells are different, and the triggering moment is the moment when the thermal runaway of the second single cell occurs; the determination module 602 is specifically used to: determine the first thermal runaway warning value corresponding to the sample battery pack based on the average value of the instantaneous voltage drop difference of the multiple second single cells.

[0116] In another possible implementation, the determination module 602 is specifically used to determine the second thermal runaway warning value corresponding to the sample battery pack based on the three-standard deviation criterion and the average value of the instantaneous drop voltage difference of the battery cells other than the second battery cell in the sample battery pack.

[0117] In another possible implementation, the acquisition module is specifically used to: obtain the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle when the vehicle is in a preset operating condition; wherein the preset operating condition includes one of the following: a stationary operating condition and a driving operating condition.

[0118] In the case of implementing the functions of the above-mentioned integrated modules in the form of hardware, this application provides a possible structure of the electronic device involved in the above-mentioned embodiments. Figure 7 As shown, the electronic device 700 includes: a processor 702 and a bus 704. Optionally, the electronic device 700 may further include a memory 701; and optionally, the electronic device 700 may further include a communication interface 703.

[0119] Processor 702 may implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the embodiments of this application. Processor 702 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. It may implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the embodiments of this disclosure. Processor 702 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like.

[0120] The communication interface 703 is used to connect to other devices via a communication network, such as Ethernet, wireless access network, wireless local area network (WLAN), etc.

[0121] The memory 701 may be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto.

[0122] As one possible implementation, memory 701 can exist independently of processor 702. Memory 701 can be connected to processor 702 via bus 704 to store instructions or program code. When processor 702 calls and executes the instructions or program code stored in memory 701, the battery thermal runaway warning method provided in the embodiment of the present application can be implemented. In another possible implementation, memory 701 can also be integrated with processor 702.

[0123] The bus 704 may be an extended industry standard architecture (EISA) bus or the like. The bus 704 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0124] In an exemplary embodiment, the present application also provides a readable storage medium having program instructions stored thereon; when the program instructions are executed by an electronic device, the electronic device implements the method described in the aforementioned embodiment. The readable storage medium can be a non-transitory readable storage medium, for example, a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0125] In an exemplary embodiment, the present application also provides a computer program product. When the computer program product is run on an electronic device, the electronic device executes the above-mentioned related method steps to implement the battery thermal runaway warning method in the above-mentioned embodiment.

[0126] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or replacements within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A battery thermal runaway early warning method, characterized in that: The method comprises: Obtaining a transient voltage drop difference of each single cell in a battery pack of a vehicle, where the transient voltage drop difference of the single cell reflects the difference between the voltage value of the single cell at a current moment and the voltage value of the single cell at a previous moment; Determining whether the battery pack of the vehicle has a thermal runaway risk based on the instantaneous voltage drop difference of each single battery; When it is determined that the battery pack of the vehicle has a risk of thermal runaway, a thermal runaway warning is issued.

2. The battery thermal runaway early warning method according to claim 1, characterized in that: The determining whether the battery pack of the vehicle has a thermal runaway risk based on the instantaneous voltage drop difference of each single battery cell includes: For a first single cell in the battery pack, if the instantaneous voltage drop difference of the first single cell is greater than or equal to a first thermal runaway warning value, and the instantaneous voltage drop differences of all other single cells in the battery pack except the first single cell are less than a second thermal runaway warning value, it is determined that the battery pack of the vehicle is at risk of thermal runaway; wherein the first single cell is any single cell in the battery pack.

3. The battery thermal runaway early warning method according to claim 2, characterized in that: Before determining whether the battery pack of the vehicle has a thermal runaway risk based on the instantaneous voltage drop difference of each single battery, the method further includes: Based on the battery pack type of the vehicle and the preset parameter correspondence, a thermal runaway warning value corresponding to the battery pack of the vehicle is determined; the preset parameter correspondence is used to reflect the thermal runaway warning values corresponding to different types of battery packs.

4. The battery thermal runaway early warning method according to claim 3, characterized in that: Before determining the thermal runaway warning value corresponding to the battery pack of the vehicle based on the correspondence between the battery pack type of the vehicle and the preset parameters, the method further includes: Thermal runaway experiments are conducted based on a variety of different types of sample battery packs to construct the preset parameter correspondence.

5. The battery thermal runaway early warning method according to claim 4, characterized in that: The thermal runaway experiment is conducted based on a variety of different types of sample battery packs to establish the preset parameter correspondence, including: For each type of sample battery pack among multiple different types of sample battery packs, triggering thermal runaway of a second single cell in the sample battery pack; wherein the second single cell is any one of the sample battery packs; When thermal runaway occurs in the second single cell, obtaining a transient voltage drop difference of the second single cell and transient voltage drop differences of other single cells in the sample battery pack except the second single cell; determining a first thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of the second single battery; determining a second thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of the other single cells in the sample battery pack except the second single cell; The preset parameter correspondence is constructed based on the first thermal runaway warning value and the second thermal runaway warning value corresponding to each type of sample battery pack.

6. The battery thermal runaway early warning method according to claim 5, characterized in that: There are multiple second single cells, and the triggering moments of the multiple second single cells are different, and the triggering moment is the moment when the second single cells are triggered to experience thermal runaway; and determining the first thermal runaway warning value corresponding to the sample battery pack based on the instantaneous voltage drop difference of the second single cells includes: A first thermal runaway warning value corresponding to the sample battery pack is determined based on an average value of the instantaneous voltage drop differences of the plurality of second single battery cells.

7. The battery thermal runaway early warning method according to claim 5, characterized in that: The determining, based on the instantaneous voltage drop difference of the other single cells except the second single cell in the sample battery pack, a second thermal runaway warning value corresponding to the sample battery pack includes: A second thermal runaway warning value corresponding to the sample battery pack is determined based on a three-times standard deviation criterion and an average value of instantaneous voltage drops of the battery cells other than the second battery cell in the sample battery pack.

8. The battery thermal runaway early warning method according to claim 1, characterized in that: The step of obtaining the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle includes: When the vehicle is in a preset operating condition, the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle is obtained; wherein the preset operating condition includes one of the following: a stationary operating condition and a driving operating condition.

9. A battery thermal runaway warning device, characterized in that: The battery thermal runaway warning device includes: an acquisition module, a determination module and a warning module; The acquisition module is used to acquire the instantaneous voltage drop difference of each single cell in the battery pack of the vehicle, where the instantaneous voltage drop difference of the single cell is used to reflect the difference between the voltage value of the single cell at a current moment and the voltage value of the single cell at a previous moment; The determination module is used to determine whether the battery pack of the vehicle has a thermal runaway risk based on the instantaneous voltage drop difference of each single battery; The early warning module is used to issue a thermal runaway early warning when it is determined that the battery pack of the vehicle has a thermal runaway risk.

10. The battery thermal runaway warning device according to claim 9, characterized in that: The determination module is specifically used to determine, for a first single cell in the battery pack, that the battery pack of the vehicle has a risk of thermal runaway when the instantaneous voltage drop difference of the first single cell is greater than or equal to a first thermal runaway warning value, and the instantaneous voltage drop differences of other single cells in the battery pack except the first single cell are all less than a second thermal runaway warning value; wherein the first single cell is any single cell in the battery pack.

11. An electronic device, characterized in that: The device includes: a processor and a memory; The memory stores instructions executable by the processor; When the processor is configured to execute the instructions, the electronic device implements the method according to any one of claims 1 to 8.

12. A vehicle, characterized in that: The vehicle includes the electronic device according to claim 11.

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