Power battery pack thermal runaway early warning method, device, equipment and medium

Abstract

The invention provides a power battery pack thermal runaway early warning method, device and equipment and a medium, and the method comprises the steps: determining battery parameters which comprise a battery diaphragm melting point temperature Tmem, an electrolyte decomposition temperature Tle, a battery high-temperature standing highest temperature Tsta, a battery high-temperature dynamic highest temperature Tdyn and a highest over-temperature fault grade temperature Tmax2N; determining a battery temperature rising speed V, and determining a theoretical highest temperature Tmax0 based on the battery parameters and the battery temperature rising speed V; the theoretical maximum temperature Tmax0 is smaller than the melting point temperature Tmem of the battery diaphragm and the decomposition temperature Tel of the electrolyte, and the theoretical maximum temperature Tmax0 is larger than the high-temperature standing maximum temperature Tsta of the battery and the high-temperature dynamic maximum temperature Tdyn of the battery; and based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, determining whether the battery state enters a thermal runaway state or not so as to carry out thermal runaway early warning. According to the scheme, the accuracy of thermal runaway judgment can be effectively improved, and the timeliness of thermal runaway early warning is improved.

Description

Technical Field

[0001] The present invention belongs to the field of electric vehicles, and particularly relates to a method, device, equipment and medium for thermal runaway warning of a power battery pack. Background Art

[0002] The power battery of an electric vehicle is generally a lithium-ion battery. The rechargeable range of a lithium-ion power battery is -20°C to 55°C, and the dischargeable range is -30°C to 55°C. Beyond these ranges, safety problems are likely to occur in the power battery. In terms of the safety of the power battery, the temperature of the battery is crucial for power safety. As the battery temperature rises, chemical changes occur in the materials inside the battery, and a large amount of heat may be generated inside the battery, even leading to an explosion. The current thermal runaway warning strategy generally focuses on whether the currently detected battery temperature T exceeds the highest temperature of the battery cell. However, the highest temperature of the battery cell cannot be directly obtained through a sensor. Therefore, the highest theoretical temperature Tmax0 is set empirically, and the insufficient accuracy of the highest theoretical temperature Tmax0 will lead to problems such as delayed reporting, missed reporting, and false reporting of thermal runaway warnings. For example, when the highest theoretical temperature Tmax0 is set too high, that is, the highest theoretical temperature Tmax0 > the highest actual temperature Tmax of the battery cell, a thermal runaway warning signal will be issued only when the actual battery temperature T > Tmax0. The delay of the thermal runaway signal may reduce the escape time of the occupants; when the highest theoretical temperature Tmax0 is set too low, that is, the highest theoretical temperature Tmax0 < Tmax, a thermal runaway warning signal will be issued when the actual battery temperature T > Tmax0, resulting in false reporting and affecting the driving experience of the thermal runaway warning. Therefore, how to obtain an accurate highest theoretical temperature Tmax0 close to the highest actual temperature Tmax and improve the accuracy of thermal runaway warning is an urgent problem to be solved. Summary of the Invention

[0003] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method, device, equipment and medium for thermal runaway warning of a power battery pack to solve the above problems.

[0004] The method for thermal runaway warning of a power battery pack provided by the present invention includes:

[0005] Determine battery parameters, where the battery parameters include the melting point temperature Tmem of the battery separator, the decomposition temperature Tele of the electrolyte, the highest temperature Tsta of the battery at high temperature when standing still, the highest temperature Tdyn of the battery at high temperature during dynamic operation, and the highest over-temperature fault level temperature Tmax2N;

[0006] Determine the battery temperature rise rate V, and determine the theoretical maximum temperature Tmax0 based on the battery parameters and the battery temperature rise rate V; the theoretical maximum temperature Tmax0 is less than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn;

[0007] Based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, determine whether the battery state has entered a thermal runaway state to provide a thermal runaway warning.

[0008] In one embodiment of the present invention, determining battery parameters includes:

[0009] After the vehicle is left at rest for a preset time at high temperature, the high temperature rest temperature of the battery is measured, and the highest high temperature rest temperature Tsta of the battery is determined among the high temperature rest temperatures of the battery;

[0010] After the battery is left at high temperature, the vehicle is tested for the battery high temperature dynamic temperature in each high temperature dynamic scenario, and the battery high temperature dynamic maximum temperature Tdyn is determined in each test battery high temperature dynamic temperature.

[0011] In one embodiment of the present invention, after determining the battery parameters, the method further includes:

[0012] Compare the battery separator melting point temperature Tmem with the electrolyte decomposition temperature Tele, and determine the smaller value as the intermediate value;

[0013] The theoretical maximum temperature Tmax0 is determined to be smaller than the intermediate value.

[0014] In one embodiment of the present invention, based on the battery parameters and the battery temperature rise rate V, determining the theoretical maximum temperature Tmax0 includes:

[0015] Compare the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn, and determine the larger value as the first determined value;

[0016] Compare the first determined value with the maximum over-temperature fault level temperature Tmax2N, and determine the larger value as the second determined value;

[0017] The second determined value is determined as the initial theoretical maximum temperature Tmax01.

[0018] In one embodiment of the present invention, after determining the second determined value as the initial theoretical maximum temperature Tmax01, the method further includes:

[0019] It takes T1 from determining that the battery temperature T is greater than the highest over-temperature fault level temperature Tmax2N to determining that it is the highest over-temperature fault level;

[0020] Determine the time T2 from when the battery temperature T is greater than or equal to the initial theoretical maximum temperature Tmax01 to when the thermal runaway state is determined;

[0021] Determine the time T3 from when the thermal runaway state is determined to when the relay is disconnected;

[0022] The theoretical maximum temperature Tmax0 is determined according to the initial theoretical maximum temperature Tmax01, the battery temperature rise rate V, and the time T1, the time T2, and the time T3.

[0023] In one embodiment of the present invention, the theoretical maximum temperature Tmax0 is determined according to the initial theoretical maximum temperature Tmax01, the battery temperature rise rate V, and the time T1, the time T2, and the time T3, including:

[0024] Add the time consumption T1, the time consumption T2 and the time consumption T3 to obtain a value T;

[0025] Multiplying the battery temperature rise rate V and the value T to obtain a third determined value;

[0026] The third determined value and the second determined value are added to obtain the theoretical maximum temperature Tmax0.

[0027] In one embodiment of the present invention, based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, determining whether the battery state enters a thermal runaway state includes:

[0028] Comparing the battery temperature T with the theoretical maximum temperature Tmax0, and if the battery temperature T is greater than or equal to the theoretical maximum temperature Tmax0, determining that the first determination condition is met;

[0029] Comparing the air pressure in the battery with a preset air pressure threshold, and if the air pressure is greater than the preset air pressure threshold, determining that the second determination condition is met;

[0030] Comparing the minimum voltage in the battery cell with a preset voltage threshold, and if the minimum voltage in the battery cell is less than the preset voltage threshold, determining that the third determination condition is met;

[0031] When the first determination condition and the second determination condition are satisfied at the same time, or when the first determination condition and the third determination condition are satisfied at the same time, the battery state is determined to be in a thermal runaway state.

[0032] The power battery pack thermal runaway warning device provided by the present invention comprises:

[0033] A parameter determination module is used to determine battery parameters, wherein the battery parameters include the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta, the battery high temperature dynamic maximum temperature Tdyn and the maximum over-temperature fault level temperature Tmax2N;

[0034] A theoretical maximum temperature determination module is used to determine a battery temperature rise rate V, and based on the battery parameters and the battery temperature rise rate V, determine a theoretical maximum temperature Tmax0; the theoretical maximum temperature Tmax0 is less than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn;

[0035] The thermal runaway determination module is used to determine whether the battery state has entered a thermal runaway state based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, so as to provide a thermal runaway warning.

[0036] The electronic device provided by the present invention comprises:

[0037] one or more processors;

[0038] A storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the electronic device implements the power battery pack thermal runaway warning method.

[0039] The computer-readable storage medium provided by the present invention stores a computer program thereon, and when the computer program is executed by a processor of a computer, the computer is enabled to execute the power battery pack thermal runaway early warning method.

[0040] Beneficial effects of the present invention: In the present invention, the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele are compared, the smaller value is determined as the middle value, and the theoretical maximum temperature Tmax0 is determined to be less than the middle value. The theoretical maximum temperature Tmax0 needs to be less than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele to reduce the occurrence of false alarms and delayed warnings. The battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn are the temperature values ​​during normal use of the battery. Therefore, the theoretical maximum temperature Tmax0 needs to be greater than the battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn to avoid affecting the normal use of the battery.

[0041] The setting of the theoretical maximum temperature Tmax0 in this solution is closer to the maximum actual temperature Tmax, which can effectively increase the accuracy of thermal runaway warning and reduce the possibility of false alarms and missed alarms.

[0042] 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

[0043] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0044] Figure 1 It is a flow chart of a power battery pack thermal runaway warning method shown in an exemplary embodiment of the present application.

[0045] Figure 2 FIG. 4 is a flow chart of determining battery parameters according to an exemplary embodiment of the present application.

[0046] Figure 3 FIG. 4 is a flow chart showing a method of determining a theoretical maximum temperature Tmax0 according to an exemplary embodiment of the present application.

[0047] Figure 4 FIG. 4 is a flow chart showing a method of determining an initial theoretical maximum temperature Tmax01 according to an exemplary embodiment of the present application.

[0048] Figure 5 It is another flow chart of a power battery pack thermal runaway warning method shown in an exemplary embodiment of the present application.

[0049] Figure 6 is another flow chart showing the determination of the theoretical maximum temperature Tmax0 according to an exemplary embodiment of the present application.

[0050] Figure 7 FIG. 4 is a flow chart showing a method of determining a thermal runaway state according to an exemplary embodiment of the present application.

[0051] Figure 8 It is a block diagram of a power battery pack thermal runaway warning device shown in an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0052] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0053] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0054] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0055] See also Figure 1 , Figure 1 It is a flow chart of a power battery pack thermal runaway warning method shown in an exemplary embodiment of the present application.

[0056] like Figure 1 As shown, in an exemplary embodiment, the power battery pack thermal runaway warning method includes at least steps S110 to S130, which are described in detail as follows:

[0057] Step S110, determining battery parameters, the battery parameters include the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta, the battery high temperature dynamic maximum temperature Tdyn and the maximum over-temperature fault level temperature Tmax2N.

[0058] First of all, it should be noted that the melting point temperature Tmem of the battery separator is affected by the material and / or process used for the battery separator. The battery separator is made of PP (polypropylene), PE (polyethylene) or other composite materials. The melting point temperature Tmem of battery separators with different materials and processes is not necessarily the same.

[0059] It should also be noted that after the battery type is determined, the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele are inherent parameters, and the relationship between the two is fixed.

[0060] Step S120, determine the battery heating rate V, and determine the theoretical maximum temperature Tmax0 based on the battery parameters and the battery heating rate V; the theoretical maximum temperature Tmax0 is less than the battery diaphragm melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn.

[0061] It should be understood that when the battery temperature T is greater than the battery separator melting point temperature Tmem or the electrolyte decomposition temperature Tele, thermal runaway has occurred for some time. At this time, the thermal runaway alarm is delayed and missed. Therefore, the theoretical maximum temperature Tmax0 needs to be lower than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele to reduce the occurrence of false alarms and delayed warnings. The battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn are the temperature values ​​during normal use of the battery. Therefore, the theoretical maximum temperature Tmax0 needs to be greater than the battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn to avoid affecting the normal use of the battery.

[0062] Here, the relationship between the theoretical maximum temperature Tmax0, the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn is recorded as: max(Tmem, Tele)>Tmax0>max(Tsta, Tdyn).

[0063] Step S130, based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, it is determined whether the battery state has entered a thermal runaway state, so as to provide a thermal runaway warning.

[0064] In this embodiment, when it is determined that the system will enter a thermal runaway state, a thermal runaway warning will be issued, and at the same time, in the thermal runaway state, the relay will be controlled to be de-energized.

[0065] like Figure 2 As shown, the process of determining the battery parameters may include step S210 and step S220, which are described in detail as follows:

[0066] Step S210 , after the vehicle is left at high temperature for a preset time, the high temperature rest temperature of the battery is measured, and the highest high temperature rest temperature Tsta of the battery is determined among the various high temperature rest temperatures of the battery.

[0067] It is worth noting that the vehicle being stationary in high temperature means that the vehicle is stationary in a high-temperature natural environment or in a simulated natural high-temperature environment.

[0068] It should also be noted that the battery has a certain high temperature resistance (such as high temperature storage performance) to ensure that thermal runaway does not occur during high temperature storage. The maximum temperature Tsta of the battery at high temperature can be obtained through the high temperature storage test of the battery cell.

[0069] Step S220 , after the battery is left at high temperature, the vehicle is made to test the battery high temperature dynamic temperature in each high temperature dynamic scene, and the battery high temperature dynamic maximum temperature Tdyn is determined in each test battery high temperature dynamic temperature.

[0070] It should be noted that all normal situations of electric vehicles that may cause high battery temperatures need to be considered to prevent battery overtemperature failures, such as high-temperature driving, high-speed overtaking at high temperatures, and rapid acceleration and deceleration at high temperatures. The dynamic maximum temperature Tdyn of the battery is determined through simulation and actual measurement.

[0071] Exemplarily, the high temperature in the battery high temperature static temperature and the battery high temperature dynamic temperature refers to an ambient temperature of the vehicle being higher than 45°C.

[0072] like Figure 3 As shown, in an exemplary embodiment, after determining the battery parameters, the method further includes at least step S310 and step S320.

[0073] Step S310, comparing the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele, and determining the smaller value as the middle value.

[0074] In this embodiment, the battery is a liquid electrolyte. For the liquid electrolyte, the melting point temperature Tmem of the battery separator is greater than the decomposition temperature Tele of the electrolyte, that is, the middle value is the decomposition temperature Tele of the electrolyte.

[0075] Step S320, determining the theoretical maximum temperature Tmax0 to be less than the middle value.

[0076] In this embodiment, the theoretical maximum temperature Tmax0 is less than the intermediate value, which is recorded as Tmax0. <Tele。

[0077] like Figure 4 As shown, in an exemplary embodiment, determining the theoretical maximum temperature Tmax0 includes steps S410 to S430.

[0078] Step S410 , comparing the battery high-temperature static maximum temperature Tsta and the battery high-temperature dynamic maximum temperature Tdyn, and determining the larger value as the first determined value.

[0079] Exemplarily, the battery high-temperature dynamic maximum temperature Tdyn is greater than the battery high-temperature static maximum temperature Tsta, that is, the first determined value is the battery high-temperature dynamic maximum temperature Tdyn.

[0080] Step S420: compare the first determined value with the maximum over-temperature fault level temperature Tmax2N, and determine the larger value as the second determined value.

[0081] Exemplarily, the temperatures of the over-temperature fault level from low to high include Tmax21, Tmax22, ..., Tmax2N. The theoretical maximum temperature Tmax0 needs to be set to be greater than the highest over-temperature fault level temperature Tmax2N, which is recorded as Tmax0>Tmax2N.

[0082] For example, according to the different performances of different types of batteries, the relationship between the battery high-temperature dynamic maximum temperature Tdyn (ie, the first determined value) and the maximum over-temperature fault level temperature Tmax2N is different. In specific use, the second determined value is determined according to the battery type.

[0083] Step S430: determining the second determined value as the initial theoretical maximum temperature Tmax01.

[0084] Exemplarily, the second determined value is determined as the initial theoretical maximum temperature Tmax01, which is expressed as Tmax01>max(Tdyn, Tmax2N).

[0085] It should be noted that the initial theoretical maximum temperature Tmax01 is only used in the process of determining the theoretical maximum temperature Tmax0.

[0086] like Figure 5 As shown, in an exemplary embodiment, after the second determined value is determined as the initial theoretical maximum temperature Tmax01, the method further includes steps S510 to S540.

[0087] Step S510 , it takes T1 from determining that the battery temperature T is greater than the highest over-temperature fault level temperature Tmax2N to determining that the battery temperature is the highest over-temperature fault level.

[0088] Exemplarily, the temperature sensor detects the battery temperature T. When it is determined that the battery temperature T is greater than the highest over-temperature fault level temperature Tmax2N, the processing time from when the battery temperature T is finally determined to be the highest over-temperature fault level is recorded as the time consumption T1.

[0089] Step S520, determining the time T2 from when the battery temperature T is greater than or equal to the initial theoretical maximum temperature Tmax01 to when the battery is determined to be in a thermal runaway state.

[0090] Exemplarily, the time from determining the highest over-temperature fault level to determining the thermal runaway state is time T2. The thermal runaway state here is determined based on the initial theoretical maximum temperature Tmax01. When the battery temperature T is greater than or equal to the initial theoretical maximum temperature Tmax01, it is determined to be a thermal runaway state.

[0091] Step S530, determining the time T3 from the time when the thermal runaway state is determined to the time when the relay is disconnected.

[0092] In this embodiment, after the thermal runaway state is determined in step S520, a relay disconnection operation is performed, and the time from the determination of the thermal runaway state to the completion of the relay disconnection operation is T3.

[0093] It should be noted that if the battery is determined to be a certain type of battery, its time consumption T1, T2, and T3 are all fixed values. T1 can be confirmed through thermal runaway testing, T2 can be found through the battery cell fault list, and T3 can be obtained from the relay specification.

[0094] Step S540, determining the theoretical maximum temperature Tmax0 according to the initial theoretical maximum temperature Tmax01, the battery temperature rise rate V, and the time T1, the time T2, and the time T3.

[0095] It is worth noting that the initial theoretical maximum temperature Tmax01 is used to judge thermal runaway only for the first time, and the thermal runaway state will be judged based on the theoretical maximum temperature Tmax0 in subsequent times.

[0096] like Figure 6 As shown, in an exemplary embodiment, the process of determining the theoretical maximum temperature Tmax0 according to the initial theoretical maximum temperature Tmax01, the battery heating speed V and the time T1, the time T2 and the time T3 at least includes steps S610 to S630.

[0097] Step S610, add the time consumption T1, the time consumption T2 and the time consumption T3 to obtain a value T.

[0098] In this embodiment, the time consumption T1, the time consumption T2 and the time consumption T3 are added together to obtain a value T, which is recorded as T=T1+T2+T3.

[0099] Step S620: multiply the battery temperature rise rate V and the value T to obtain a third determined value.

[0100] In this embodiment, the third determined value K is expressed as K=V*T=V(T1+T2+T3).

[0101] Step S630: Add the third determined value and the second determined value to obtain a theoretical maximum temperature Tmax0.

[0102] In this embodiment, the calculation formula of the theoretical maximum temperature Tmax0 is:

[0103] Tmax0=max(Tdyn,Tmax2N)+V(T1+T2+T3).

[0104] like Figure 7As shown, in an exemplary embodiment, the process of determining whether the battery state enters a thermal runaway state based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T at least includes steps S710 to S740.

[0105] Step S710: compare the battery temperature T with the theoretical maximum temperature Tmax0. If the battery temperature T is greater than or equal to the theoretical maximum temperature Tmax0, it is determined that the first determination condition is met.

[0106] In this embodiment, when thermal runaway occurs, the battery temperature T needs to be greater than or equal to the theoretical maximum temperature Tmax0.

[0107] Step S720, comparing the air pressure in the battery with a preset air pressure threshold, if the air pressure is greater than the preset air pressure threshold, it is determined that the second determination condition is met.

[0108] In this embodiment, when thermal runaway occurs, the air pressure needs to be greater than a preset air pressure threshold.

[0109] Step S730, comparing the minimum voltage in the battery cell with a preset voltage threshold, if the minimum voltage in the battery cell is less than the preset voltage threshold, it is determined that the third determination condition is met.

[0110] In this embodiment, when thermal runaway occurs, the minimum power supply in the battery cell must be less than a preset voltage threshold.

[0111] Step S740: When the first determination condition and the second determination condition are satisfied at the same time, or when the first determination condition and the third determination condition are satisfied at the same time, the battery state is determined to be in a thermal runaway state.

[0112] In this embodiment, a thermal runaway state is determined only when the first determination condition and the second determination condition are satisfied at the same time, or the first determination condition and the third determination condition are satisfied at the same time.

[0113] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0114] like Figure 8 As shown, the exemplary power battery pack thermal runaway warning device includes:

[0115] The parameter determination module 810 is used to determine the battery parameters, which include the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta, the battery high temperature dynamic maximum temperature Tdyn and the maximum over-temperature fault level temperature Tmax2N;

[0116] Theoretical maximum temperature determination module 820, used to determine the battery temperature rise rate V, and determine the theoretical maximum temperature Tmax0 based on the battery parameters and the battery temperature rise rate V; the theoretical maximum temperature Tmax0 is less than the battery diaphragm melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn;

[0117] The thermal runaway determination module 830 is used to determine whether the battery state enters a thermal runaway state based on the theoretical maximum temperature Tmax0, the battery temperature rise rate V and the currently detected battery temperature T, so as to provide a thermal runaway warning.

[0118] In this exemplary power battery pack thermal runaway warning device, the battery parameters of each type of battery can be stored in the cloud or server in the form of a data list after being determined, and then the corresponding battery parameters can be retrieved and determined according to the battery type. After that, the theoretical maximum temperature determination module determines the theoretical maximum temperature Tmax0 according to the determination logic of the theoretical maximum determination module, so that the subsequent thermal runaway determination module can determine the battery state according to the theoretical maximum temperature Tmax0.

[0119] It should be noted that the thermal runaway warning device for the power battery pack provided in the above embodiment and the thermal runaway warning method for the power battery pack provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment and will not be repeated here. In practical applications, the thermal runaway warning device for the power battery pack provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0120] An embodiment of the present application also provides an electronic device, comprising: one or more processors; a storage device for storing one or more programs, and when the one or more programs are executed by the one or more processors, the electronic device implements the power battery pack thermal runaway warning method provided in the above-mentioned embodiments.

[0121] It should be noted that the computer-readable medium shown in the embodiment of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or determined as a part of a carrier wave, wherein a computer-readable computer program is carried. This propagated data signal may take a variety of forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate or transmit a program for use by or in conjunction with an instruction execution system, apparatus or device. A computer program contained on a computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0122] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. Wherein, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some implementations determined as replacements, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0123] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0124] Another aspect of the present application further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer executes the thermal runaway warning method for a power battery pack as described above. The computer-readable storage medium may be included in the electronic device described in the above embodiment, or may exist independently without being assembled into the electronic device.

[0125] Another aspect of the present application also provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the power battery pack thermal runaway warning method provided in each of the above embodiments.

[0126] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A thermal runaway warning method for a power battery pack, characterized in that: include: Determine battery parameters, the battery parameters including the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta, the battery high temperature dynamic maximum temperature Tdyn and the maximum over-temperature fault level temperature Tmax2N; Determine the battery temperature rise rate V, and determine the theoretical maximum temperature Tmax0 based on the battery parameters and the battery temperature rise rate V; the theoretical maximum temperature Tmax0 is less than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn; Based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, determine whether the battery state has entered a thermal runaway state to provide a thermal runaway warning.

2. The thermal runaway warning method for a power battery pack according to claim 1, characterized in that: Determine battery parameters, including: After the vehicle is left at rest for a preset time at high temperature, the high temperature rest temperature of the battery is measured, and the highest high temperature rest temperature Tsta of the battery is determined among the high temperature rest temperatures of the battery; After the battery is left at high temperature, the vehicle is tested for the battery high temperature dynamic temperature in each high temperature dynamic scenario, and the battery high temperature dynamic maximum temperature Tdyn is determined in each test battery high temperature dynamic temperature.

3. The thermal runaway warning method for a power battery pack according to claim 1, characterized in that: After determining the battery parameters, the method further includes: Compare the battery separator melting point temperature Tmem with the electrolyte decomposition temperature Tele, and determine the smaller value as the intermediate value; The theoretical maximum temperature Tmax0 is determined to be smaller than the intermediate value.

4. The thermal runaway warning method for a power battery pack according to claim 3, characterized in that: Determine the theoretical maximum temperature Tmax0, including: Compare the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn, and determine the larger value as the first determined value; Compare the first determined value with the maximum over-temperature fault level temperature Tmax2N, and determine the larger value as the second determined value; The second determined value is determined as the initial theoretical maximum temperature Tmax01.

5. The thermal runaway warning method for a power battery pack according to claim 4, characterized in that: After determining the second determined value as the initial theoretical maximum temperature Tmax01, the method further includes: It takes T1 from determining that the battery temperature T is greater than the highest over-temperature fault level temperature Tmax2N to determining that it is the highest over-temperature fault level; Determine the time T2 from when the battery temperature T is greater than or equal to the initial theoretical maximum temperature Tmax01 to when the thermal runaway state is determined; Determine the time T3 from when the thermal runaway state is determined to when the relay is disconnected; The theoretical maximum temperature Tmax0 is determined according to the initial theoretical maximum temperature Tmax01, the battery temperature rise rate V, and the time T1, the time T2, and the time T3.

6. The thermal runaway warning method for a power battery pack according to claim 5, characterized in that: Determining the theoretical maximum temperature Tmax0 according to the initial theoretical maximum temperature Tmax01, the battery temperature rise rate V, and the time T1, the time T2, and the time T3 includes: Add the time consumption T1, the time consumption T2 and the time consumption T3 to obtain a value T; Multiplying the battery temperature rise rate V and the value T to obtain a third determined value; The third determined value and the second determined value are added to obtain the theoretical maximum temperature Tmax0.

7. The thermal runaway warning method for a power battery pack according to claim 1, characterized in that: Based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, determine whether the battery state has entered a thermal runaway state, including: Comparing the battery temperature T with the theoretical maximum temperature Tmax0, and if the battery temperature T is greater than or equal to the theoretical maximum temperature Tmax0, determining that the first determination condition is met; Comparing the air pressure in the battery with a preset air pressure threshold, and if the air pressure is greater than the preset air pressure threshold, determining that the second determination condition is met; Comparing the minimum voltage in the battery cell with a preset voltage threshold, and if the minimum voltage in the battery cell is less than the preset voltage threshold, determining that the third determination condition is met; When the first determination condition and the second determination condition are satisfied at the same time, or when the first determination condition and the third determination condition are satisfied at the same time, the battery state is determined to be in a thermal runaway state.

8. A thermal runaway warning device for a power battery pack, characterized in that: include: A parameter determination module is used to determine battery parameters, wherein the battery parameters include the battery separator melting point temperature Tmem, the electrolyte decomposition temperature Tele, the battery high temperature static maximum temperature Tsta, the battery high temperature dynamic maximum temperature Tdyn and the maximum over-temperature fault level temperature Tmax2N; A theoretical maximum temperature determination module is used to determine a battery temperature rise rate V, and based on the battery parameters and the battery temperature rise rate V, determine a theoretical maximum temperature Tmax0; the theoretical maximum temperature Tmax0 is less than the battery separator melting point temperature Tmem and the electrolyte decomposition temperature Tele, and the theoretical maximum temperature Tmax0 is greater than the battery high temperature static maximum temperature Tsta and the battery high temperature dynamic maximum temperature Tdyn; The thermal runaway determination module is used to determine whether the battery state has entered a thermal runaway state based on the theoretical maximum temperature Tmax0 and the currently detected battery temperature T, so as to provide a thermal runaway warning.

9. A device, characterized in that: include: one or more processors and memory, A computer program is stored in the memory, and when the one or more processors execute the computer program, the device is caused to perform the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, which, when executed by one or more processors, causes the device to perform the method according to any one of claims 1 to 7.

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