Battery thermal runaway early warning method and system, vehicle-mounted equipment and storage medium

Abstract

The invention provides a battery thermal runaway early warning method and system, vehicle-mounted equipment and a storage medium, and the method comprises the steps: obtaining the working condition data of a to-be-detected battery, the working condition data comprising state data and environment data of an environment where the to-be-detected battery is located, and the state data comprising a temperature parameter, an electrical parameter, a health state parameter and a charge state parameter; the working condition data are input into the battery thermal runaway simulation model, thermal runaway simulation is conducted on the to-be-tested battery, the early warning parameter extreme value of the to-be-tested battery under the working condition data is obtained, the early warning parameter extreme value comprises the temperature parameter extreme value, and the battery thermal runaway simulation model is constructed through the thermal performance of the battery under various working condition data in the whole life cycle; and comparing the temperature parameter with the temperature parameter extreme value, and carrying out battery thermal runaway early warning according to a comparison result. Through the battery thermal runaway simulation model in the full life cycle of the battery, accurate early warning of thermal runaway can be realized according to the working condition data of the battery for the batteries with different health states and charge states.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and in particular to a battery thermal runaway warning method, system, vehicle-mounted equipment and storage medium. Background Art

[0002] With the enhancement of global environmental awareness and the transformation of energy structure, lithium-ion batteries have been widely used in the field of new energy vehicles due to their green rechargeability, long life, and high energy density. As its core power source, lithium-ion batteries not only determine the vehicle's endurance, but also directly affect the cost and safety of the entire vehicle. Based on the demand for long driving range and fast charging of new energy vehicles, battery manufacturers continue to pursue higher energy density and faster charging rates. The improvement of high energy density and fast charging performance also brings challenges to battery safety, especially the increased risk of thermal runaway, which poses a serious threat to personal and property safety.

[0003] At present, the early warning of battery thermal runaway is mostly achieved by monitoring battery voltage, internal resistance, temperature, air pressure and smoke signals. When voltage, internal resistance, air pressure and smoke signals are used as early warning monitoring signals, it is easy to have a late warning, and it is difficult to achieve the early warning effect of thermal runaway. Temperature, as an external manifestation before battery thermal runaway, can provide a characteristic signal for early thermal runaway. However, using temperature as a characteristic signal for early warning also has the following shortcomings. First, it is necessary to set up a sensor in the battery that does not affect the normal charging and discharging of the battery, is resistant to high temperature, has high resolution and sensitivity, increases the development cost of the whole package, and reduces the space utilization rate; secondly, it is necessary to carry out a large number of experiments under different working conditions. Due to the limitations of experimental conditions and the fact that most warnings are developed only based on the test results of fresh batteries, the performance of the battery in the entire life cycle is not considered, and it cannot reflect all the working conditions of the battery pack in the entire life cycle, which actually has the risk of false alarms and missed alarms. Therefore, the battery thermal runaway warning still has the problems of limited sensor use and limited monitoring data, resulting in insufficient reliability, timeliness and accuracy of the warning. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present application discloses a battery thermal runaway warning method, system, vehicle-mounted device and storage medium, which are used to solve the technical problem of poor battery thermal runaway warning effect in the prior art.

[0005] In a first aspect, the present application provides a battery thermal runaway warning method, the method comprising: obtaining operating condition data of a battery to be tested, the operating condition data comprising status data and environmental data of the environment in which it is located, the status data comprising temperature parameters, electrical parameters, health status parameters and charge state parameters; inputting the operating condition data into a battery thermal runaway simulation model, performing a thermal runaway simulation on the battery to be tested according to the status data and the environmental data, obtaining the warning parameter extreme values ​​of the battery to be tested under the operating condition data, the warning parameter extreme values ​​comprising temperature parameter extreme values, the battery thermal runaway simulation model being constructed through the thermal performance of the battery under various operating condition data throughout its life cycle; comparing the temperature parameter with the temperature parameter extreme values, and issuing a battery thermal runaway warning based on the comparison result.

[0006] In one embodiment of the present application, the battery thermal runaway simulation model includes an aging model and a thermal safety mechanism model, and the temperature parameter extreme values ​​include, from small to large, a first temperature parameter extreme value, a second temperature parameter extreme value, a third temperature parameter extreme value, and a fourth temperature parameter extreme value; the operating condition data is input into the battery thermal runaway simulation model, and a thermal runaway simulation is performed on the battery to be tested according to the state data and the environmental data to obtain the warning parameter extreme value of the battery to be tested under the operating condition data, including: inputting the state data and the environmental data into the aging model, and predicting the temperature parameter threshold value for safe operation of the battery to be tested according to the state data and the environmental data as the first temperature parameter extreme value; inputting the state data and the environmental data into the thermal safety mechanism model, and predicting the second temperature parameter extreme value of the battery to be tested in the self-heating stage, the third temperature parameter extreme value in the battery voltage sag stage, and the fourth temperature parameter extreme value from the voltage sag to the thermal runaway stage according to the state data and the environmental data.

[0007] In one embodiment of the present application, the method for constructing the aging model includes: preparing test batteries in multiple health states and multiple charge states; obtaining a first temperature parameter change curve and a first electrical parameter change curve of the test battery under different environmental data, generating multiple first test data under different operating conditions, and obtaining first model parameters, wherein the first model parameters at least include solid phase diffusion coefficient, liquid phase diffusion coefficient, solid phase conductivity, liquid phase conductivity, reaction rate constant and open circuit voltage; according to the first model parameters, building a benchmark aging model combined with an electrothermal coupling model, and inputting the multiple first test data into the benchmark aging model to simulate the heat generation, temperature rise and voltage of the battery under different operating conditions to obtain a first simulation result; according to the first simulation result, optimizing the first model parameters to obtain the aging model.

[0008] In one embodiment of the present application, the method for constructing the thermal safety mechanism model includes: preparing test batteries in multiple health states and multiple charge states; obtaining the second temperature parameter change curve and the second electrical parameter change curve of the test battery in the self-heating stage, the battery voltage drop stage and the voltage drop to the thermal runaway stage under different environmental data when thermal runaway occurs, generating multiple second test data under different operating conditions, and obtaining second model parameters, the second model parameters at least including reaction enthalpy, reaction activation energy and pre-frequency factor; constructing a baseline thermal safety mechanism model according to the second model parameters, and inputting the multiple second test data into the baseline thermal safety mechanism model to simulate the heat generation, temperature rise and voltage of the battery under different operating conditions and at different stages when thermal runaway occurs, and obtaining a second simulation result; optimizing the second model parameters according to the second simulation result to obtain the thermal safety mechanism model.

[0009] In one embodiment of the present application, the temperature parameter is compared with the temperature parameter extreme value, and a battery thermal runaway warning is performed according to the comparison result, including: if the temperature parameter is greater than the first temperature parameter extreme value and less than or equal to the second temperature parameter extreme value, a first-level battery cooling measure is triggered; if the temperature parameter is greater than the second temperature parameter extreme value and less than or equal to the third temperature parameter extreme value, a first-level thermal runaway warning and a second-level battery cooling measure are triggered; if the temperature parameter is greater than the third temperature parameter extreme value and less than or equal to the fourth temperature parameter extreme value, a second-level thermal runaway warning, a third-level battery cooling measure and a thermal runaway protection measure are triggered; if the temperature parameter is greater than the fourth temperature parameter extreme value, a third-level thermal runaway warning, a fourth-level battery cooling measure, as well as a thermal runaway protection and a thermal runaway propagation measure are triggered.

[0010] In one embodiment of the present application, the temperature parameter includes a temperature value and a temperature rise rate, and the temperature parameter extreme value includes a temperature extreme value and a temperature rise rate extreme value; comparing the temperature parameter with the temperature parameter extreme value, and triggering a corresponding thermal runaway warning measure according to the comparison result, includes: comparing the temperature value with the temperature extreme value, and comparing the temperature rise rate with the temperature rise rate extreme value; when the temperature value is greater than the temperature extreme value, and the temperature rise rate is greater than the temperature rise rate extreme value, triggering the thermal runaway warning measure.

[0011] In one embodiment of the present application, the electrical parameter includes a voltage parameter, and the warning parameter extreme value also includes a voltage parameter extreme value; before triggering the thermal runaway warning measure, it also includes: comparing the voltage parameter with the voltage parameter extreme value; when the voltage parameter is greater than the voltage parameter extreme value, entering the triggering stage of the thermal runaway warning measure.

[0012] In the second aspect, the present application provides a battery thermal runaway warning system, the system comprising: an acquisition module, used to obtain operating condition data of a battery to be tested, the operating condition data comprising status data and environmental data of the environment in which it is located, the status data comprising temperature parameters, electrical parameters, health status parameters and charge state parameters; a simulation module, used to input the operating condition data into a battery thermal runaway simulation model, perform a thermal runaway simulation on the battery to be tested according to the status data and the environmental data, and obtain the extreme values ​​of warning parameters of the battery to be tested under the operating condition data, the extreme values ​​of warning parameters comprising extreme values ​​of temperature parameters, and the battery thermal runaway simulation model is constructed through the thermal performance of the battery under various operating condition data throughout its life cycle; a warning module, used to compare the temperature parameter with the extreme values ​​of the temperature parameter, and issue a battery thermal runaway warning based on the comparison result.

[0013] In a third aspect, the present application provides a vehicle-mounted device, comprising: one or more processors; a storage device for storing one or more programs, when the one or more programs are executed by one or more processors, the vehicle-mounted device implements the battery thermal runaway warning method described in the first aspect.

[0014] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor of a computer, the computer executes the battery thermal runaway warning method described in the first aspect.

[0015] As described above, the battery thermal runaway warning method, system, vehicle-mounted device and storage medium provided by the embodiments of the present application have the following beneficial effects:

[0016] First, the working condition data of the battery to be tested is obtained, and the working condition data includes the operating status data of the battery to be tested and the environmental data of the environment in which it is located, wherein the status data includes temperature parameters, electrical parameters, health status parameters and charge status parameters, and then the working condition data is input into the battery thermal runaway simulation model, and the thermal runaway simulation of the battery to be tested is performed to obtain the extreme values ​​of the warning parameters of the battery to be tested under the working condition data, wherein the extreme values ​​of the warning parameters include the extreme values ​​of the temperature parameters. The battery thermal runaway simulation model is constructed by the thermal performance of the battery under various working condition data throughout the life cycle, and finally the temperature parameters are compared with the extreme values ​​of the temperature parameters, and the battery thermal runaway warning is performed according to the comparison results. Through the battery thermal runaway simulation model throughout the battery life cycle, for batteries in different health states and charge states, the extreme values ​​of the warning parameters under the working condition data of the battery can be predicted according to the environmental data, temperature parameters and electrical parameters, and based on the extreme values ​​of the warning parameters, it is judged whether the battery reaches the thermal runaway warning conditions, so as to realize the accurate warning of thermal runaway and achieve the effect of early thermal runaway warning.

[0017] 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

[0018] 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:

[0019] Figure 1 is a schematic diagram of an implementation environment of a battery thermal runaway warning system shown in an exemplary embodiment of the present application;

[0020] Figure 2 is a flow chart of a battery thermal runaway early warning method shown in an exemplary embodiment of the present application;

[0021] Figure 3 is a flow chart of a thermal safety mechanism model construction method shown in an exemplary embodiment of the present application;

[0022] Figure 4 is a flowchart of a specific battery thermal runaway early warning method shown in an exemplary embodiment of the present application;

[0023] Figure 5 is a block diagram of a battery thermal runaway warning system shown in an exemplary embodiment of the present application;

[0024] Figure 6 It is a structural schematic diagram of a vehicle-mounted device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0025] The following will describe the implementation methods of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific implementation methods, 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 application. It should be understood that the preferred embodiments are only for illustrating the present application, not for limiting the scope of protection of the present application.

[0026] It should be noted that the illustrations provided in the following embodiments are only used to illustrate the basic concept of the present application in a schematic manner, and therefore the illustrations only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the form, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0027] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application 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 application difficult to understand.

[0028] First of all, it should be noted that the early warning for battery thermal runaway is usually achieved by monitoring battery voltage, internal resistance, temperature, air pressure and smoke signals. However, the inventors of this application have found that when voltage, internal resistance, air pressure and smoke signals are used as early warning monitoring signals, it is easy to have a late warning, and it is difficult to achieve the early warning effect of thermal runaway; temperature, as an external manifestation before battery thermal runaway, can provide a characteristic signal for early thermal runaway. However, using temperature as a characteristic signal for early warning also has the following shortcomings. First, it is necessary to set a sensor in the battery that does not affect the normal charging and discharging of the battery, is resistant to high temperature, has high resolution and sensitivity, increases the development cost of the whole package, and reduces the space utilization rate; secondly, it is necessary to carry out a large number of experiments under different working conditions. Due to the limitations of experimental conditions and the fact that most warnings are only developed based on the test results of fresh batteries, the performance of the battery in the entire life cycle is not considered, and all working conditions in the entire life cycle of the battery pack cannot be reflected, which actually leads to the risk of false alarms and missed alarms. Therefore, the battery thermal runaway warning still has the problems of limited sensor use and limited monitoring data, resulting in insufficient reliability, timeliness and accuracy of the warning.

[0029] Therefore, see Figure 1 , Figure 1 FIG. 1 is a schematic diagram of an implementation environment of a battery thermal runaway warning system shown in an exemplary embodiment of the present application. Figure 1 As shown, the implementation environment includes a vehicle 110 and a battery thermal runaway warning system 120, wherein the battery thermal runaway warning system 120 is embedded in the vehicle 110, and is used to realize thermal runaway warning of the battery in the vehicle 110. The battery thermal runaway warning system 120 includes but is not limited to a vehicle system, an on-board computer, etc. Through a battery thermal runaway simulation model throughout the battery life cycle, for batteries in different health states and charge states, the extreme values ​​of the warning parameters under the battery operating condition data can be predicted based on environmental data, temperature parameters, and electrical parameters, and based on the extreme values ​​of the warning parameters, it is determined whether the battery has reached the thermal runaway warning condition, thereby realizing accurate warning of thermal runaway and achieving the effect of early thermal runaway warning.

[0030] See also Figure 2 , Figure 2 is a flowchart of a battery thermal runaway warning method shown in an exemplary embodiment of the present application. The method can be applied to Figure 1The implementation environment shown is a schematic diagram. It should be understood that the method may also be applicable to other exemplary implementation environments, and this embodiment does not limit the implementation environment to which the method is applicable.

[0031] like Figure 2 As shown, in an exemplary embodiment, the battery thermal runaway warning method includes at least steps S210 to S230, which are described in detail as follows:

[0032] Step S210, obtaining the operating condition data of the battery to be tested, the operating condition data including status data and environmental data of the environment in which the battery is located, the status data including temperature parameters, electrical parameters, health status parameters and charge state parameters.

[0033] Among them, status data refers to various internal parameter data of the battery to be tested during operation, including at least temperature parameters, electrical parameters, health status parameters and charge status parameters of the battery to be tested; environmental data refers to external environmental parameters of the battery during operation, including at least ambient temperature data.

[0034] It should be noted that temperature parameters include at least temperature value and temperature rise rate, electrical parameters include at least voltage value, discharge power value and DCR (Direct Current Resistance) value, health status parameter refers to SOH (State of Health), and charge status parameter refers to SOC (State of Charge). In addition, considering that in the heat exchange system corresponding to the battery, the battery will exchange heat with the surrounding environment, which will affect the battery temperature, therefore, the environmental data includes at least the coolant temperature.

[0035] Step S220, input the operating condition data into the battery thermal runaway simulation model, perform thermal runaway simulation on the battery to be tested according to the state data and the environmental data, and obtain the extreme values ​​of warning parameters of the battery to be tested under the operating condition data. The extreme values ​​of warning parameters include extreme values ​​of temperature parameters. The battery thermal runaway simulation model is constructed through the thermal performance of the battery under various operating condition data throughout the life cycle.

[0036] In this embodiment, the influence of various parameters during battery operation on battery thermal runaway and the influence of battery performance degradation during use on battery thermal runaway are taken into consideration. The thermal runaway simulation of the battery to be tested is carried out through all operating data such as temperature parameters, electrical parameters, health status parameters, charge status parameters and environmental data of the battery to be tested, and the extreme values ​​of warning parameters are obtained, which fully reflects the different characteristics of the extreme values ​​of warning parameters of the battery to be tested under different operating data, that is, the extreme values ​​of warning parameters can be adjusted in real time according to different operating data, and the corresponding extreme values ​​of warning parameters can be predicted according to the specific operating data of the battery to be tested, so as to perform thermal runaway warning according to the dynamic extreme values ​​of warning parameters, thereby ensuring the reliability and accuracy of thermal runaway warning.

[0037] It should be noted that the extreme value of the warning parameter refers to the threshold condition that triggers the thermal runaway warning; the extreme value of the temperature parameter refers to the temperature threshold condition that triggers the thermal runaway warning. In addition, the battery thermal runaway simulation model is constructed through the thermal performance of the battery under various operating conditions throughout the life cycle, that is, through the thermal performance corresponding to various operating conditions under various health states and charge states. The battery thermal runaway simulation model constructed in this way can meet the thermal runaway warning of the battery under different health states, charge states and other specific operating conditions, further improving the reliability and accuracy of the battery thermal runaway warning and reducing the risk of false alarms and missed alarms in the actual thermal runaway warning.

[0038] In one embodiment, a battery thermal runaway simulation model includes an aging model and a thermal safety mechanism model, and the temperature parameter extreme values ​​include, from small to large, a first temperature parameter extreme value, a second temperature parameter extreme value, a third temperature parameter extreme value, and a fourth temperature parameter extreme value; the operating condition data is input into the battery thermal runaway simulation model, and a thermal runaway simulation is performed on the battery to be tested according to the state data and the environmental data to obtain the warning parameter extreme value of the battery to be tested under the operating condition data, including: inputting the state data and the environmental data into the aging model, and predicting the temperature parameter threshold value for safe operation of the battery to be tested according to the state data and the environmental data as the first temperature parameter extreme value; inputting the state data and the environmental data into the thermal safety mechanism model, and predicting the second temperature parameter extreme value of the battery to be tested in the self-heating stage, the third temperature parameter extreme value in the battery voltage sag stage, and the fourth temperature parameter extreme value from the voltage sag to the thermal runaway stage according to the state data and the environmental data.

[0039] Among them, the battery aging model refers to the model used to predict the performance degradation process of the battery during its life cycle, and the battery thermal safety mechanism model refers to the model used to describe and predict the battery's behavior under extreme temperature conditions and its thermal runaway risk.

[0040] In this embodiment, by introducing the aging model and the thermal safety mechanism model, the temperature parameter extreme value of the battery to be tested under the operating condition data can be obtained, and by comparing it with the current temperature parameter, the battery health status can be monitored to achieve the role of early thermal runaway warning. At the same time, by introducing the aging model and the thermal safety mechanism model for battery health monitoring and thermal runaway warning, the cost increase caused by the layout of additional sensors, as well as the reduction of space utilization and battery energy density, can be avoided. In addition, by introducing the aging model and the thermal safety mechanism model, these two models are used to predict the temperature parameter extreme value, and there is no need to conduct a large number of experiments under different operating conditions to obtain the temperature parameter extreme value under different operating condition data, making the battery thermal runaway warning simple and efficient.

[0041] In this embodiment, the operating condition data is input into the aging model, and the temperature parameter threshold for safe operation of the battery to be tested is predicted based on the operating condition data as the first temperature parameter extreme value, wherein the first temperature parameter extreme value refers to the upper boundary value of the temperature parameter when the battery to be tested is working normally under the operating condition data. The introduction of the aging model can predict the temperature parameter trend of the battery to be tested under normal operation, and can perform early identification and early warning before thermal runaway, so as to better monitor and manage battery health.

[0042] In this embodiment, the operating condition data is input into the thermal safety mechanism model, and the second temperature parameter extreme value of the battery to be tested in the self-heating stage, the third temperature parameter extreme value in the battery voltage drop stage, and the fourth temperature parameter extreme value from the voltage drop to the thermal runaway stage are predicted according to the operating condition data, wherein the self-heating stage is the stage where the battery begins to generate heat, but the heat is not enough to cause a significant temperature rise, and the battery is still in a controllable state, the battery voltage drop stage is the stage where the internal temperature of the battery gradually increases, the internal resistance of the battery increases, and the battery voltage begins to drop, indicating that the battery begins to enter an unstable state, and the stage from the voltage drop to the thermal runaway stage is when the battery temperature continues to rise and reaches a critical point, and the temperature rises sharply and is in an uncontrollable state. The second temperature parameter extreme value refers to the upper limit boundary value of the temperature parameter in the self-heating stage, the third temperature parameter extreme value refers to the upper limit boundary value of the temperature parameter in the battery voltage drop stage, and the fourth temperature parameter extreme value refers to the upper limit boundary value of the temperature parameter from the voltage drop to the thermal runaway stage. The introduction of the thermal safety mechanism model can reflect the thermal runaway mechanism of the battery at different stages, making the thermal runaway warning more accurate.

[0043] In a possible embodiment, the temperature parameter includes a temperature value and a temperature rise rate, and the temperature parameter extreme value includes a temperature extreme value and a temperature rise rate extreme value. The operating condition data is input into the aging model, and the first temperature parameter extreme value for safe operation of the battery under test is predicted based on the operating condition data, including the first temperature extreme value T1 and the first temperature rise rate V1; the operating condition data is input into the thermal safety mechanism model, and the second temperature parameter extreme value (including the second temperature extreme value T2 and the second temperature rise rate V2) of the battery under test in the self-heating stage, the third temperature parameter extreme value (third temperature extreme value T3 and third temperature rise rate V3) in the battery voltage drop stage, and the fourth temperature parameter extreme value (fourth temperature extreme value T4 and fourth temperature rise rate V4) in the stage from voltage drop to thermal runaway.

[0044] In one embodiment, the method for constructing an aging model includes: preparing test batteries in multiple health states and multiple charge states; obtaining a first temperature parameter change curve and a first electrical parameter change curve of the test battery under different environmental data, generating multiple first test data under different operating conditions, and obtaining first model parameters, the first model parameters at least including solid phase diffusion coefficient, liquid phase diffusion coefficient, solid phase conductivity, liquid phase conductivity, reaction rate constant and open circuit voltage; according to the first model parameters, building a benchmark aging model combined with an electrothermal coupling model, and inputting multiple first test data into the benchmark aging model to simulate the heat generation, temperature rise and voltage of the battery under different operating conditions to obtain a first simulation result; according to the first simulation result, optimizing the first model parameters to obtain an aging model.

[0045] In this embodiment, test batteries in multiple health states and multiple charge states can be prepared according to the accelerated aging test method, for example, increasing the temperature or discharge rate of the battery to obtain test batteries in different health states and different charge states. It should be understood that the test batteries in multiple health states and multiple charge states include test batteries in different charge states in the same health state and test batteries in the same charge state in different health states. The first temperature parameter change curve and the first electrical parameter change curve of the test battery under different environmental data are obtained to generate multiple first test data under different working condition data, wherein the multiple first test data under different working condition data refer to different temperature parameters, electrical parameters, health state parameters, charge state parameters and test data under environmental data, that is, one first test data refers to a specific temperature parameter, electrical parameter, health state parameter, charge state parameter and test data under temperature data. In addition, different health states include the entire life cycle of the battery, and different charge states include the entire range of the battery from full discharge to full charge.

[0046] In this embodiment, the baseline aging model is constructed in combination with the electrothermal coupling model, wherein the electrothermal coupling model includes a thermal model and an electrochemical model. The thermal model is introduced to calculate the heat generation and temperature rise of the battery under different operating conditions through the solid-phase conductivity and the liquid-phase conductivity; the electrochemical model and the thermal model are coupled to calculate the voltage of the battery under different operating conditions through the solid-liquid phase diffusion coefficient, the reaction rate constant of the electrochemical reaction, and the open circuit voltage. Therefore, the first model parameters of the baseline aging model constructed in combination with the electrothermal coupling model include at least the solid-phase diffusion coefficient, the liquid-phase diffusion coefficient, the solid-phase conductivity, the liquid-phase conductivity, the reaction rate constant, and the open circuit voltage.

[0047] In this embodiment, the heat generation, temperature rise and voltage conditions of the battery under different operating conditions are simulated through the reference aging model to obtain a first simulation result, which is a result of comparing the heat generation, temperature rise and voltage conditions of a standard battery corresponding to the first test data with the heat generation, temperature rise and voltage conditions of the battery obtained by simulation, so as to iteratively optimize the first model parameters according to the error between the simulation and the standard, thereby obtaining the aging model, thereby ensuring the simulation accuracy of the aging model.

[0048] In this way, the introduction of an aging model combined with an electrochemical-thermal coupling model can predict the heat generation, temperature rise and voltage trend of the battery under normal operation. Combined with the battery thermal management system, it can better monitor and manage battery health.

[0049] It should also be noted that the thermal model is introduced to calculate the heat generation and temperature rise of the operating condition data. First, according to the law of conservation of energy, that is, the conservation of energy of heat generation, heat dissipation and heat conduction of the battery during operation, the equation is as follows:

[0050]

[0051] Wherein, C represents the specific heat capacity of the battery; m represents the mass of the battery; T represents the temperature of the battery; t represents the time; represents the rate of change of temperature T with time t; λ represents the thermal conductivity of the battery; It represents the rate of change of the temperature gradient of the battery; q represents the heat generation rate of the battery.

[0052] Then the battery will exchange heat with the surrounding environment, such as liquid cooling in the battery pack. The convection heat transfer coefficient h can be set in the model to change the heat transfer situation, which can be used as the boundary condition of the above equation (1). The boundary condition for heat exchange between the battery and the surrounding environment is as follows:

[0053]

[0054] Where λ represents the thermal conductivity of the battery; represents the rate of change of the battery's temperature gradient; h represents the battery's convective heat transfer coefficient; A represents the battery's heat transfer surface area; T represents the battery's temperature; T f is the fluid (coolant) temperature.

[0055] For battery heat generation, the heat generation formula includes reversible heat (electrochemical heat generation), irreversible heat (electrochemical reaction overpotential heat generation) and ohmic heat (solid phase ohmic heat and liquid phase ohmic heat). The equations are as follows:

[0056] Reversible Heat:

[0057]

[0058] Among them, q r represents the ideal heat generation without energy loss during the electrochemical reaction; a is the effective area of ​​the electrode; F is the Faraday constant; j n represents the net current density; Represents the partial derivative of the reversible potential of the electrochemical reaction with respect to temperature;

[0059] Irreversible heat:

[0060] q act =aFj n η Formula (4)

[0061] Among them, q act represents the energy loss caused by the overpotential in the electrochemical reaction; a is the effective area of ​​the electrode; F is the Faraday constant; j n represents the net current density; η represents the overpotential;

[0062] Ohm Heat:

[0063]

[0064] Among them, q ohm It represents the total heat generated when the current passes through the solid electrode material and the electrolyte; σ represents the conductivity of the solid electrode; Φ s represents the electric potential in the solid electrode; represents the potential gradient in the solid electrode; κ represents the conductivity of the electrolyte; Φ e represents the electric potential in the electrolyte; represents the gradient of the potential in the electrolyte; R represents the universal gas constant; T represents the temperature of the battery; F represents the Faraday constant; f ± represents the activity factor of the ion; c e represents electrolyte concentration; t + represents the transmission number of positive ions; represents the activity factor f ± For electrolyte concentration c e The partial derivative of represents the gradient of the natural logarithm of the electrolyte concentration; represents solid-phase ohmic heat; Represents liquid phase ohmic heat.

[0065] Thirdly, the electrochemical model and the thermal model are coupled, the temperature inside the battery is calculated by the thermal model, and then the temperature is fed back to the electrochemical model. The voltage of the battery under different operating conditions is calculated through the solid-liquid phase diffusion coefficient, the reaction rate constant of the electrochemical reaction, and the open circuit voltage. Among them, the relationship between many physical properties of battery materials and temperature mostly follows the Arrhenius formula, so the Arrhenius equation is used to calculate the impact of temperature on parameters.

[0066] The equation of solid phase diffusion coefficient and temperature is:

[0067]

[0068] Among them, D s,j,T represents the solid phase diffusion coefficient at temperature T; D represents the diffusion coefficient; s represents the solid phase; j represents the type of battery material or electrode material type; D s,j,ref Indicates that at the reference temperature T ref Solid phase diffusion coefficient under ads,j represents the adsorption activation energy; R represents the universal gas constant; T represents the temperature of the battery; T ref Indicates the reference temperature of the battery.

[0069] The equation for liquid phase diffusion coefficient and temperature is:

[0070]

[0071] Among them, D e,j,T represents the liquid phase diffusion coefficient at temperature T; D represents the diffusion coefficient; e represents the liquid phase; j represents the type of battery material or electrode material type; D e,j,ref Indicates that at the reference temperature T ref Liquid phase diffusion coefficient under ade,j represents the activation energy of adsorption and desorption; R represents the universal gas constant; T represents the temperature of the battery; T ref Indicates the reference temperature of the battery.

[0072] The equation for the reaction rate constant and temperature is:

[0073]

[0074] Among them, k j,T represents the reaction rate constant at temperature T; K represents the reaction rate constant; j represents the type of battery substance or electrode material type; k j,ref Indicates that at the reference temperature T refLiquid phase diffusion coefficient under ar,j represents activation energy; R represents the universal gas constant; T represents the temperature of the battery; T ref Indicates the reference temperature of the battery.

[0075] The equation for open circuit voltage and temperature is:

[0076]

[0077] Among them, U j Indicates open circuit voltage; T x Indicates the temperature of the battery; SOC j (x, t) represents the state of charge at position x and time t; U j (SOC j (x,t),T x ) represents the position x and time t at a given temperature T x The open circuit voltage at temperature T x and state of charge SOC j Open circuit voltage at (x, t); T ref Indicates the reference temperature of the battery; U j (SOC j (x,t),T ref ) indicates that at the reference temperature T ref and state of charge SOC j Open circuit voltage at (x, t); Indicates the open circuit voltage U j (SOC j The partial derivative of (x,t) with respect to temperature.

[0078] In one embodiment, a method for constructing a thermal safety mechanism model includes: preparing test batteries in multiple health states and multiple charge states; obtaining a second temperature parameter change curve and a second electrical parameter change curve of the test battery in the self-heating stage, the battery voltage drop stage, and the voltage drop to the thermal runaway stage when thermal runaway occurs under different environmental data, generating multiple second test data under different operating conditions, and obtaining second model parameters, the second model parameters at least including reaction enthalpy, reaction activation energy and pre-frequency factor; constructing a baseline thermal safety mechanism model based on the second model parameters, and inputting the multiple second test data into the baseline thermal safety mechanism model to simulate the heat generation, temperature rise and voltage of the battery under different operating conditions and at different stages when thermal runaway occurs, and obtaining a second simulation result; optimizing the second model parameters based on the second simulation result to obtain a thermal safety mechanism model.

[0079] In this embodiment, test batteries in multiple health states and multiple charge states can also be prepared according to the accelerated aging test method, such as increasing the temperature or discharge rate of the battery to obtain test batteries in different health states and different charge states. It should be understood that the test batteries in multiple health states and multiple charge states include test batteries in different charge states in the same health state and test batteries in the same charge state in different health states. The second temperature parameter change curve and the second electrical parameter change curve of the test battery in the self-heating stage, the battery voltage drop stage and the voltage drop to the thermal runaway stage when thermal runaway occurs are obtained under different environmental data, and multiple second test data under different working condition data are generated, wherein the multiple second test data under different working condition data refer to different temperature parameters, electrical parameters, health state parameters, charge state parameters and test data under environmental data, that is, one second test data refers to a specific temperature parameter, electrical parameter, health state parameter, charge state parameter and test data under temperature data. In addition, different health states include the entire life cycle of the battery, and different charge states include the entire range of the battery from full discharge to full charge.

[0080] In this embodiment, a thermal safety mechanism model is introduced to calculate the heat generation, temperature rise and voltage of the battery under different operating conditions through reaction enthalpy, reaction activation energy and pre-frequency factor. Therefore, the second model parameter of the thermal safety mechanism model includes at least reaction enthalpy, reaction activation energy and pre-frequency factor. Among them, the pre-frequency factor reflects the number and probability of effective collisions of reactant molecules in the battery per unit time, and predicts the rate of chemical reaction and its change with temperature. Reaction enthalpy, reaction activation energy and pre-frequency factor can be based on DSC test, or based on thermal runaway experimental data, combined with MATLAB (Matrix Laboratory) and other software for parameter identification and acquisition.

[0081] In this embodiment, the heat generation, temperature rise and voltage conditions of the battery under different operating conditions are simulated through the thermal safety mechanism model to obtain a second simulation result, which is a result of comparing the heat generation, temperature rise and voltage conditions of a standard battery corresponding to the second test data with the heat generation, temperature rise and voltage conditions of the simulated battery, so as to iteratively optimize the second model parameters according to the error between the simulation and the standard, thereby obtaining the thermal safety mechanism model, thereby ensuring the simulation accuracy of the thermal safety mechanism model.

[0082] In this way, the introduction of the thermal safety mechanism model can reflect the thermal runaway mechanism of the battery at different stages, and control it with the four equations of the thermal runaway mechanism as the heat source. The chain reaction of the thermal runaway process and the superposition of multiple exothermic reactions are taken into account, making the prediction of the warning parameter thresholds at different stages of thermal runaway more accurate.

[0083] It should also be noted that the thermal safety mechanism model is introduced, and the thermal runaway mechanism of the battery is represented by four equations, that is, the chemical reactions of the battery in different temperature ranges are different. For example, SEI film decomposition and regeneration will occur at 70-80°C, and the heat generated by different reactions will continue to accumulate, eventually causing thermal runaway of the battery. Therefore, by studying the reactions at different stages, the heat generation, temperature rise and voltage of the battery under different operating conditions can be judged, so as to achieve the purpose of early warning. Specifically, the four equations include the following formulas:

[0084] SEI film decomposition reaction:

[0085]

[0086] Among them, Q sei Represents the heat generation power of SEI film decomposition reaction; H sei represents the enthalpy change of SEI film decomposition reaction; W sei Indicates the quality of SEI film; A sei Represents the reaction area of ​​SEI film; E sei represents the activation energy of the SEI film decomposition reaction; R represents the universal gas constant; T represents the temperature of the battery; C sei Indicates the concentration of SEI film;

[0087] The corresponding dynamic equation is:

[0088]

[0089] in, It indicates the rate of change of SEI film concentration over time, and the meanings of other formula parameters are the same as above;

[0090] Negative electrode and electrolyte reaction:

[0091]

[0092] Among them, Q ne Indicates the heat generation power of the reaction between the negative electrode and the electrolyte; H ne represents the enthalpy change of the reaction between the negative electrode and the electrolyte; W ne Indicates the mass of the negative electrode; A ne Represents the reaction area of ​​the negative electrode; E ne represents the activation energy of the reaction between the negative electrode and the electrolyte; R represents the universal gas constant; T represents the temperature of the battery; t sei Indicates the time of SEI film decomposition; t ref Indicates the reference time of SEI film decomposition; C ne Indicates the concentration of the negative electrode and electrolyte reaction;

[0093] The corresponding dynamic equation is:

[0094]

[0095] in, Indicates the rate of change of the negative electrode material concentration over time; the meanings of other formula parameters are the same as above;

[0096]

[0097] in, Indicates the rate of change of SEI film decomposition time over time; other formula parameters have the same meaning as above;

[0098] Positive electrode and electrolyte reaction:

[0099]

[0100] Among them, Q pe Indicates the heat generation power of the reaction between the positive electrode and the electrolyte; H pe Represents the enthalpy change of the reaction between the positive electrode and the electrolyte; W pe Indicates the quality of the positive electrode; A pe represents the reaction area of ​​the positive electrode; α represents the degree of reaction (0-1); E pe represents the activation energy of the reaction between the positive electrode and the electrolyte; R represents the universal gas constant; T represents the temperature of the battery; C pe Indicates the concentration of the positive electrode and electrolyte reaction;

[0101] The corresponding dynamic equation is:

[0102]

[0103] in, Indicates the rate of change of the positive electrode material concentration over time; the meanings of other formula parameters are the same as above;

[0104] Decomposition reaction of electrolyte solution:

[0105]

[0106] Among them, Q e Indicates the heat generation power of the decomposition reaction of the electrolyte solution; H e represents the enthalpy change of the decomposition reaction of the electrolyte solution; W e Indicates the mass of the electrolyte solution; A e Represents the reaction area of ​​the electrolyte solution; E e represents the activation energy of the decomposition reaction of the electrolyte solution; R represents the universal gas constant; T represents the temperature of the battery; C e Indicates the concentration of the electrolyte solution;

[0107] The corresponding dynamic equation is:

[0108]

[0109] in, Indicates the rate of change of electrolyte solution concentration over time; other formula parameters have the same meaning as above.

[0110] Therefore, the total heat generation power is:

[0111] Q abuse =Q sei +Q ne +Q pe +Q e Formula (19)

[0112] Among them, Q abuse Indicates the total heat generation power; Q sei It represents the heat generation power of the decomposition reaction of SEI membrane (Solid Electrolyte Interface membrane); Q ne Indicates the heat generation power of the reaction between the negative electrode and the electrolyte; Q pe Indicates the heat generation power of the reaction between the positive electrode and the electrolyte; Q e Indicates the heat generation power of the decomposition reaction of the electrolyte solution.

[0113] In one possible embodiment, see Figure 3 , Figure 3 FIG. 1 is a flow chart showing a method for constructing a thermal safety mechanism model according to an exemplary embodiment of the present application. Figure 3 As shown in the figure, the specific steps of building a thermal safety mechanism model using COMSOL (multi-physics simulation software) include: physical field interface selection, for the thermal safety mechanism model, select the three-dimensional solid heat transfer module for transient calculation, and select the appropriate physical field according to the physical characteristics of the model; model drawing, according to the geometric shape of the battery thermal safety mechanism, use the COMSOL modeling tool to create a geometric model; parameter and four equation settings, set the first model parameters and four equations of the model; define the thermal physical parameters of the battery, according to the material and structure of the battery, define the relevant thermal physical parameters, such as thermal conductivity, specific heat capacity, etc.; set the battery boundary conditions, according to the actual application environment of the battery, set the battery boundary conditions, such as temperature, heat flow, etc.; set the thermal runaway reaction rate equation, according to the chemical reaction characteristics of the battery, set the thermal runaway reaction rate equation; divide the grid, according to the complexity of the model and the computing resources, divide the appropriate grid to ensure the calculation accuracy and efficiency of the model; post-processing and model optimization, according to the simulation results, perform post-processing analysis, and obtain the thermal runaway mechanism model after optimizing the model.

[0114] Step S230, comparing the temperature parameter with the temperature parameter extreme value, and issuing a battery thermal runaway warning based on the comparison result.

[0115] In this embodiment, the temperature parameter is compared with the temperature parameter extreme value, and if the temperature parameter is greater than the temperature parameter extreme value, a battery thermal runaway warning is issued.

[0116] In one embodiment, the temperature parameter is compared with the temperature parameter extreme value, and a battery thermal runaway warning is performed according to the comparison result, including: if the temperature parameter is greater than the first temperature parameter extreme value and less than or equal to the second temperature parameter extreme value, a first-level battery cooling measure is triggered; if the temperature parameter is greater than the second temperature parameter extreme value and less than or equal to the third temperature parameter extreme value, a first-level thermal runaway warning and a second-level battery cooling measure are triggered; if the temperature parameter is greater than the third temperature parameter extreme value and less than or equal to the fourth temperature parameter extreme value, a second-level thermal runaway warning, a third-level battery cooling measure and a thermal runaway protection measure are triggered; if the temperature parameter is greater than the fourth temperature parameter extreme value, a third-level thermal runaway warning, a fourth-level battery cooling measure, as well as a thermal runaway protection and a thermal runaway propagation measure are triggered.

[0117] In this embodiment, the temperature parameter extreme values ​​include, from small to large, the first temperature parameter extreme value for safe operation of the battery to be tested, the second temperature parameter extreme value in the self-heating stage, the third temperature parameter extreme value in the battery voltage sag stage, and the fourth temperature parameter extreme value in the stage from the voltage sag to the thermal runaway stage. As the temperature parameter increases, the thermal runaway becomes more difficult to control. Therefore, different temperature parameter ranges trigger different thermal runaway warning measures. The larger the temperature parameter, the higher the level of thermal runaway warning measures. In this way, by determining the warning measure level according to the size of the specific temperature parameter and providing corresponding protection and cooling measures, the thermal runaway of the battery can be effectively controlled and processed, and accurate warning of battery thermal runaway can be achieved.

[0118] In this embodiment, the intensity of the cooling measures from the first level battery cooling measure to the fourth level battery cooling measure increases; the warning level from the first level thermal runaway warning to the third level thermal runaway warning increases.

[0119] In a possible embodiment, when the temperature parameter exceeds the first temperature parameter extreme value, or above the temperature parameter extreme value, the operating condition data and the corresponding temperature parameter extreme value will be fed back to the cloud to determine the thermal runaway problem.

[0120] In a possible embodiment, if the temperature parameter is greater than the second temperature parameter extreme value and less than or equal to the third temperature parameter extreme value, and if the temperature parameter is greater than the third temperature parameter extreme value and less than or equal to the fourth temperature parameter extreme value, the battery stops working.

[0121] In a possible embodiment, when a thermal runaway level 1 warning, a thermal runaway level 2 warning, or a thermal runaway level 3 warning is given, the system notifies in the form of sound or image. It should be understood that different levels of warnings have different forms of sound or image, for example, different alarm sound frequencies and different image contents.

[0122] In one possible implementation, when the third temperature parameter extreme value corresponding to the battery voltage drop stage is obtained according to the thermal safety mechanism model, the total duration t1 of the battery voltage drop stage is also obtained, and when the fourth temperature parameter extreme value corresponding to the stage from the voltage drop to the occurrence of thermal runaway is obtained, the total duration t2 of the thermal runaway stage is also obtained.

[0123] As a possible embodiment, the total duration t1 of the battery voltage drop stage is obtained, and a potential thermal runaway risk can be warned in advance based on t1. The total duration t2 of the thermal runaway stage is obtained, and a specific warning strategy can be formulated based on t2 to ensure that timely and effective measures can be taken after thermal runaway occurs.

[0124] In one embodiment, the temperature parameters include a temperature value and a temperature rise rate, and the temperature parameter extreme values ​​include a temperature extreme value and a temperature rise rate extreme value; the temperature parameters are compared with the temperature parameter extreme values, and corresponding thermal runaway warning measures are triggered according to the comparison results, including: comparing the temperature value with the temperature extreme value, and comparing the temperature rise rate with the temperature rise rate extreme value; when the temperature value is greater than the temperature extreme value, and the temperature rise rate is greater than the temperature rise rate extreme value, the thermal runaway warning measures are triggered.

[0125] In this embodiment, the thermal runaway warning measures are determined by combining the two temperature parameters of temperature value and temperature rise rate. In this way, the false alarm problem of thermal runaway warning under a single temperature parameter is avoided, and the accuracy of thermal runaway warning is improved.

[0126] In one embodiment, the electrical parameters include voltage parameters, and the warning parameter extreme values ​​also include voltage parameter extreme values; before triggering the thermal runaway warning measures, it also includes: comparing the voltage parameters with the voltage parameter extreme values; when the voltage parameter is greater than the voltage parameter extreme value, entering the triggering stage of the thermal runaway warning measures.

[0127] In this embodiment, the voltage parameter extreme values ​​also include, from small to large, a first voltage parameter extreme value for safe operation of the battery to be tested, a second voltage parameter extreme value in the self-heating stage, a third voltage parameter extreme value in the battery voltage drop stage, and a fourth voltage parameter extreme value in the thermal runaway stage.

[0128] In this embodiment, the thermal runaway warning measures are determined by combining the temperature parameter and the voltage parameter. In this way, the problem of false alarms of thermal runaway warnings under a single parameter is avoided, and the accuracy of thermal runaway warnings is improved.

[0129] See also Figure 4 , Figure 4 FIG. 1 is a flowchart of a specific battery thermal runaway warning method shown in an exemplary embodiment of the present application. Figure 4 As shown, the specific steps of the battery thermal runaway warning method are detailed as follows:

[0130] Step S410, building an aging model in combination with the thermocouple model, and building a thermal safety mechanism model;

[0131] Step S420, real-time monitoring of battery operating data, and inputting the data into an aging model and a thermal safety mechanism model respectively;

[0132] Step S430, obtaining a first temperature parameter extreme value and a first voltage parameter extreme value for safe operation of the battery through an aging model, obtaining a second temperature parameter extreme value and a second voltage parameter extreme value of the battery in a self-heating stage, a third temperature parameter extreme value and a third voltage parameter extreme value in a battery voltage drop stage, and a fourth temperature parameter threshold and a fourth voltage parameter extreme value in a thermal runaway stage through a thermal safety mechanism model;

[0133] Step S440, comparing the monitored temperature parameter and voltage parameter with the extreme values ​​of the temperature parameter and the extreme values ​​of the voltage parameter obtained by simulation respectively;

[0134] Step S450: triggering corresponding thermal runaway warning measures according to the comparison result.

[0135] The above-mentioned battery thermal runaway warning method first obtains the operating condition data of the battery to be tested, and the operating condition data includes the operating status data of the battery to be tested and the environmental data of the environment in which it is located, wherein the status data includes temperature parameters, electrical parameters, health status parameters and charge status parameters, and then the operating condition data is input into the battery thermal runaway simulation model, and the thermal runaway simulation is performed on the battery to be tested to obtain the warning parameter extreme value of the battery to be tested under the operating condition data, wherein the warning parameter extreme value includes the temperature parameter extreme value, and the battery thermal runaway simulation model is constructed by the thermal performance of the battery under various operating condition data throughout the life cycle, and finally the temperature parameter is compared with the temperature parameter extreme value, and the battery thermal runaway warning is performed according to the comparison result. Through the battery thermal runaway simulation model throughout the battery life cycle, for batteries in different health states and charge states, the warning parameter extreme value under the battery operating condition data can be predicted according to the environmental data, temperature parameters and electrical parameters, and based on the warning parameter extreme value, it is judged whether the battery reaches the thermal runaway warning condition, so as to realize the accurate warning of thermal runaway and achieve the effect of early thermal runaway warning.

[0136] See also Figure 5 , Figure 5 is a block diagram of a battery thermal runaway warning system shown in an exemplary embodiment of the present application. The system can be applied to Figure 1 The implementation environment shown is a schematic diagram. It should be understood that the system may also be applicable to other exemplary implementation environments, and this embodiment does not limit the implementation environment to which the system is applicable.

[0137] like Figure 5As shown, in an exemplary embodiment, the battery thermal runaway warning system 500 includes at least an acquisition module 510, a simulation module 520 and a warning module 530, which are described in detail as follows:

[0138] An acquisition module 510 is used to acquire the operating condition data of the battery to be tested, the operating condition data including the state data and the environmental data of the environment in which the battery is located, the state data including the temperature parameter, the electrical parameter, the health state parameter and the charge state parameter;

[0139] The simulation module 520 is used to input the operating condition data into the battery thermal runaway simulation model, perform thermal runaway simulation on the battery to be tested according to the operating condition data, and obtain the extreme value of the warning parameter of the battery to be tested under the operating condition data. The extreme value of the warning parameter includes the extreme value of the temperature parameter. The battery thermal runaway simulation model is constructed by the thermal performance of the battery under various operating condition data in the whole life cycle;

[0140] The early warning module 530 is used to compare the temperature parameter with the temperature parameter extreme value and issue a battery thermal runaway early warning according to the comparison result.

[0141] It should be noted that the battery thermal runaway warning system provided in the above embodiment and the battery thermal runaway warning method provided in the above embodiment belong to the same concept, wherein the contents of the operations performed by each module have been described in detail in the method embodiment and will not be repeated here.

[0142] See also Figure 6 , Figure 6 It is a structural schematic diagram of a vehicle-mounted device provided in one embodiment of the present application. Figure 6 The structure diagram of the computer system of the vehicle-mounted device suitable for implementing the embodiment of the present application is shown. It should be noted that: Figure 6 The computer system 600 of the vehicle-mounted device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0143] like Figure 6 As shown, the computer system 600 includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 602 or the program loaded from the storage part 608 to the random access memory (RAM) 603, such as executing the method in the above embodiment. In the RAM 603, various programs and data required for system operation are also stored. The CPU 601, the ROM 602 and the RAM 603 are connected to each other through the bus 604. The input / output (I / O) interface 605 is also connected to the bus 604.

[0144] The following components are connected to the I / O interface 605: an input section 606 including a keyboard, a mouse, etc.; an output section 607 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 610 as needed so that a computer program read therefrom is installed into the storage section 608 as needed.

[0145] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 609, and / or installed from a removable medium 611. When the computer program is executed by a central processing unit (CPU) 601, various functions defined in the system of the present application are executed.

[0146] The present application also 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 battery thermal runaway warning method as described above. The computer-readable storage medium may be included in the vehicle-mounted device described in the above embodiment, or may exist independently without being assembled into the vehicle-mounted device.

[0147] It should be noted that the computer-readable medium shown in the embodiment of the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can 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 can 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 as part of a carrier wave, wherein a computer-readable computer program is carried. This propagated data signal can 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.

[0148] 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 alternative implementations, the functions marked in the box can also occur in a different order from the order 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.

[0149] 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.

[0150] The above embodiments are merely illustrative of the principles and effects of the present application, and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. 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 in the present application shall still be covered by the claims of the present application.

Claims

1. A battery thermal runaway early warning method, characterized in that: The method comprises: Acquire the working condition data of the battery to be tested, wherein the working condition data includes status data and environmental data of the environment in which the battery is located, and the status data includes temperature parameters, electrical parameters, health status parameters and charge state parameters; Inputting the operating condition data into a battery thermal runaway simulation model, performing thermal runaway simulation on the battery to be tested according to the state data and the environmental data, and obtaining an extreme value of a warning parameter of the battery to be tested under the operating condition data, wherein the extreme value of the warning parameter includes an extreme value of a temperature parameter, and the battery thermal runaway simulation model is constructed by the thermal performance of the battery under various operating condition data within the entire life cycle; The temperature parameter is compared with the temperature parameter extreme value, and a battery thermal runaway warning is issued according to the comparison result.

2. The battery thermal runaway early warning method according to claim 1, characterized in that: The battery thermal runaway simulation model includes an aging model and a thermal safety mechanism model, and the temperature parameter extreme values ​​include, from small to large, a first temperature parameter extreme value, a second temperature parameter extreme value, a third temperature parameter extreme value, and a fourth temperature parameter extreme value; The step of inputting the operating condition data into a battery thermal runaway simulation model, performing a thermal runaway simulation on the battery to be tested according to the state data and the environmental data, and obtaining an extreme value of a warning parameter of the battery to be tested under the operating condition data includes: Inputting the state data and the environmental data into the aging model, and predicting a temperature parameter threshold for safe operation of the battery under test according to the state data and the environmental data as the first temperature parameter extreme value; The state data and the environmental data are input into the thermal safety mechanism model, and the second temperature parameter extreme value of the battery to be tested in the self-heating stage, the third temperature parameter extreme value in the battery voltage drop stage, and the fourth temperature parameter extreme value in the stage from the voltage drop to the thermal runaway stage are predicted based on the state data and the environmental data.

3. The battery thermal runaway early warning method according to claim 2, characterized in that: The construction method of the aging model includes: Prepare test batteries in various health states and various states of charge; Obtaining a first temperature parameter change curve and a first electrical parameter change curve of the test battery under different environmental data, generating a plurality of first test data under different operating conditions, and obtaining first model parameters, wherein the first model parameters at least include a solid phase diffusion coefficient, a liquid phase diffusion coefficient, a solid phase conductivity, a liquid phase conductivity, a reaction rate constant, and an open circuit voltage; According to the first model parameters, a reference aging model combined with an electrothermal coupling model is constructed, and the plurality of first test data are input into the reference aging model to simulate heat generation, temperature rise, and voltage of the battery under different operating conditions to obtain a first simulation result; According to the first simulation result, the first model parameters are optimized to obtain the aging model.

4. The battery thermal runaway early warning method according to claim 2, characterized in that: The construction method of the thermal safety mechanism model includes: Prepare test batteries in various health states and various states of charge; Obtaining a second temperature parameter change curve and a second electrical parameter change curve of the test battery in the self-heating stage, the battery voltage sudden drop stage, and the stage from the voltage sudden drop to the thermal runaway stage when thermal runaway occurs under different environmental data, generating a plurality of second test data under different operating condition data, and obtaining second model parameters, wherein the second model parameters at least include reaction enthalpy, reaction activation energy, and pre-frequency factor; According to the second model parameters, a reference thermal safety mechanism model is constructed, and the plurality of second test data are input into the reference thermal safety mechanism model to simulate the heat generation, temperature rise and voltage of the battery under different operating conditions and at different stages when thermal runaway occurs, so as to obtain a second simulation result; According to the second simulation result, the second model parameters are optimized to obtain the thermal safety mechanism model.

5. The battery thermal runaway early warning method according to claim 2, characterized in that: The comparing the temperature parameter with the temperature parameter extreme value and performing a battery thermal runaway warning according to the comparison result includes: If the temperature parameter is greater than the first temperature parameter extreme value and less than or equal to the second temperature parameter extreme value, a first-level battery cooling measure is triggered; If the temperature parameter is greater than the second temperature parameter extreme value and less than or equal to the third temperature parameter extreme value, a first-level thermal runaway warning and a second-level battery cooling measure are triggered; If the temperature parameter is greater than the third temperature parameter extreme value and less than or equal to the fourth temperature parameter extreme value, the second-level thermal runaway warning, the third-level battery cooling measures and the thermal runaway protection measures are triggered; If the temperature parameter is greater than the fourth temperature parameter extreme value, the third-level thermal runaway warning, fourth-level battery cooling measures, thermal runaway protection and thermal runaway propagation measures are triggered.

6. The battery thermal runaway early warning method according to any one of claims 1 to 4, characterized in that: The temperature parameters include temperature value and temperature rise rate, and the temperature parameter extreme values ​​include temperature extreme value and temperature rise rate extreme value; The comparing the temperature parameter with the temperature parameter extreme value and triggering corresponding thermal runaway warning measures according to the comparison result includes: Comparing the temperature value with the temperature extreme value, and comparing the temperature rise rate with the temperature rise rate extreme value; When the temperature value is greater than the temperature extreme value, and the temperature rise rate is greater than the temperature rise rate extreme value, the thermal runaway warning measure is triggered.

7. The battery thermal runaway early warning method according to claim 6, characterized in that: The electrical parameter includes a voltage parameter, and the warning parameter extreme value also includes a voltage parameter extreme value; Before triggering the thermal runaway warning measure, the method further includes: comparing the voltage parameter with the voltage parameter extreme value; When the voltage parameter is greater than the voltage parameter extreme value, the thermal runaway warning measure triggering phase is entered.

8. A battery thermal runaway warning system, characterized in that: The system comprises: An acquisition module, used to acquire the working condition data of the battery to be tested, wherein the working condition data includes state data and environmental data of the environment in which the battery is located, wherein the state data includes temperature parameters, electrical parameters, health state parameters and charge state parameters; A simulation module, used for inputting the operating condition data into a battery thermal runaway simulation model, performing thermal runaway simulation on the battery to be tested according to the state data and the environmental data, and obtaining an extreme value of a warning parameter of the battery to be tested under the operating condition data, wherein the extreme value of the warning parameter includes an extreme value of a temperature parameter, and the battery thermal runaway simulation model is constructed by the thermal performance of the battery under various operating condition data within the entire life cycle; The early warning module is used to compare the temperature parameter with the temperature parameter extreme value and issue a battery thermal runaway early warning according to the comparison result.

9. A vehicle-mounted device, characterized in that: include: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the vehicle-mounted device to implement the battery thermal runaway warning method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Computer-readable instructions are stored thereon, and when the computer-readable instructions are executed by a processor of a computer, the computer is caused to execute the battery thermal runaway early warning method as claimed in any one of claims 1 to 7.

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